Document: Report of the Panel
Date: 27 October 1998
Document codes: WT/DS76/R
Complainant: U.S.
Respondent: Japan
Third parties: Brazil, EU, Hungary
Dispute stage: Mutually Agreed Solution
Agreements cited: Art. 2, 4, 5, 7  Sanitary and Phytosanitary Measures (SPS)Art. XI  GATT 1994Art. 4  AgricultureArt. 8  Sanitary and Phytosanitary Measures (SPS)

Japan – Measures Affecting Agricultural Products
Report of the Panel
The report of the Panel on Japan – Measures Affecting Agricultural Products is being circulated to all
Members, pursuant to the DSU. The report is being circulated as an unrestricted document from
27 October 1998 pursuant to the Procedures for the Circulation and Derestriction of WTO Documents
(WT/L/160/Rev.1). Members are reminded that in accordance with the DSU only parties to the
dispute may appeal a panel report. An appeal shall be limited to issues of law covered in the Panel
report and legal interpretations developed by the Panel. There shall be no ex parte communications
with the Panel or Appellate Body concerning matte rs under consideration by the Panel or Appellate
Body.Note by the Secretariat: This Panel Report shall be adopted by the Dispute Settlement Body (DSB) within 60 days after the date of its
circulation unless a party to the dispute decides to appeal or the DSB decides by consensus not to adopt the report. If the Pa nel Report is
appealed to the Appellate Body, it shall not be considered for adoption by the DSB until after the completion of the appeal. I nformation on
the current status of the Panel Report is available from the WTO Secretariat.

I. INTRODUCTION
1.1 In a communication dated 7 April 1997, the United States requested consultations with Japan
pursuant to Article 4 of the Understanding on Rules and Procedures Governing the Settlement of
Disputes ("DSU"), Article 11 of the Agreement on the Application of Sanitary and Phytosanitary
Measures ("SPS Agreement"), Article XXIII of the General Agreement on Tariffs and Trade 1994
("GATT 1994"), and Article 19 of the Agreement on Agriculture regarding the prohibition by Japan
of imports of certain agricultural products.1
1.2 The United States specifically alleged that, for each agricultural product for which Japan
required quarantine treatment, Japan prohibited the importation of each variety of that product until
the quarantine treatment had been tested for that variety, even though the treatment had proven
effective with respect to other varieties of the same product. The United States claimed that Japan's
prohibition adversely affected exports of US agricultural products, and, furthermore, that Japan's
measure appeared to be inconsistent with the obligations of Japan under the SPS Agreement, the
GATT 1994 and the Agreement on Agriculture. The provisions of these agreements with which these
measure appeared to be inconsistent included, but were not limited to: (i) SPS Agreement, Articles 2,
4, 5 and 8; (ii) GATT 1994, Article XI; and, (iii) the Agreement on Agriculture, Article 4. The
measures also appeared to nullify or impair benefits accruing to the United States directly or indirectly
under the cited agreements. Consultations were held on 5 June 1997, but failed to settle the dispute.
2
1.3 In a communication dated 3 October 1997, the United States requested the Dispute Settlement
Body ("DSB") to establish a panel with standard te rms of reference as set out in Article 7 of the
DSU.3 The US claims of inconsistency in their Request for the Establishment of a Panel were
identical to those set out in their request for consultations, except for an additional claim of
inconsistency under Article 7 of the SPS Agreement.
1.4 On 18 November 1997, the DSB established a panel pursuant to the request of the United
States, in accordance with Article 6 of the DSU. 4 In accordance with Article 7.1 of the DSU, the
terms of reference of the Panel were:
"To examine, in the light of the relevant provisions of the covered agreements cited by
the United States in document WT/DS76/2, the matter referred to the DSB by the
United States in that document and to make such findings as will assist the DSB in
making the recommendations or in giving the rulings provided for in those
agreements."
1.5 On 18 December 1997, the Panel was constituted with the following composition:
Chairman: Mr. Kari Bergholm
Panelists: Mr. Germain Denis
Mr. Eiríkur Einarsson

1 WT/DS76/1 (Request for Consultations by the United States).
2 WT/DS76/2 (Request for the Establishment of a Panel by the United States).
3 WT/DS76/2 (Request for the Establishment of a Panel by the United States).
4 WT/DS76/3 (Constitution of a Panel Established at the Request of the United States).

1.6 The European Communities, Hungary and Brazil reserved their right to participate in the
Panel proceedings as third parties.
1.7 The Panel met with the parties on 2 and 3 April 1998. It met with third parties on
3 April 1998. The Panel consulted scientific and technical experts and met with them on
23 June 1998. The Panel held a second meeting with the parties on 24 June 1998.
1.8 On 3 July 1998 the Chairman of the Panel informed the DSB that the Panel had not been able
to issue its report within six months. The reasons for that delay were stated in document WT/DS76/4.
1.9 The Panel issued its interim report on 6 August 1998. On 21 September 1998, on request by
Japan, an interim review meeting was held with the parties. The Final Report was circulated to the
parties on 6 October 1998. The report was circulated to Members in all three languages on [27
October 1998].
II. FACTUAL ASPECTS
A. GENERAL
1. Codling moth
2.1 Codling moth ( Cydia pomonella ) is a pest which invades apples, cherries, nectarines and
other fruit crops. Newly-hatched larvae of codling moth are known to enter into the fruit. In the
United States, the codling moth is a pest of apples and walnuts; it is also known, on occasion, to
infest nectarines and cherries. Other hosts of codling moth include apricots, plums, pears and quinces.
2.2 There are four identifiable life stages of the codling moth: egg, larva, pupa and adult. Mated
female adults lay their eggs on a suitable substrate such as leaves, nuts or fruit. All life stages are
highly dependent upon temperature for development; the higher the temperature, the more rapid the
development. After the eggs hatch, newly hatched first stage (instar) larvae find a suitable host to
complete their development. They usually burro w into the host. The larvae will molt (shed their
skin) four times thereafter inside the fruit, thus producing five larval growth phases called instars.
When mature, the fifth instar larvae will exit the host to form a pupae within a silken cocoon. The
cocoon is usually formed on the bark of the tree or in the litter at the base of the host plant.
2.3 The next generation of adult moths will exit from the pupae in 1-2 weeks. Depending on
temperature, emergence may take longer. Unde r optimum conditions, developmental time from egg
to adult is about 30-40 days. As daylight hours become shorter (10 hours light; 14 hours dark) during
the late summer and fall, mature fifth instar larvae will exit the host, but hibernate through the winter
as mature larvae within cocoons on bark or litter at the tree base. This larval hibernation (diapause) is
a mechanism for survival through the winter. The diapausing larvae will form pupae in the spring
when daylight hours and temperature begin to increase toward 14 daylight hours or more. Depending
upon temperature, moths will emerge in three to four weeks after the pupae are formed.
2.4 The seasonality of host fruits is important vis-à-vis what life stages of the codling moth might
be expected to occur at harvest. In the United States, walnuts are harvested after diapause has been
induced in mature larvae. Thus the quarantine trea tment for codling moth in walnuts is more severe
(using comparatively higher levels of fumigant) than that required for fruits such as cherries and
nectarines.

2.5 The fruit development of apples coincides with the time, mid-to-late summer, during which
the codling moth is numerous. Severe economic losses can occur if codling moth is not adequately
controlled in the field. The quarantine treatment applied to harvested apples is a multiple treatment
involving cold temperature and a methyl bromide trea tment. The cold treatment destroys most of the
codling moth eggs and the fumigation destroys any remaining larvae.
2.6 In contrast to walnuts and apples, cherries are an early spring/early summer crop and only
eggs or non-diapausing larvae would be expected to be found. With regard to nectarines, the harvest
of nectarines in the United States begins in May and ends in late July to early August, before diapause
is induced.
2.7 The Japanese archipelago forms a chain spreading across 3,000 km. from the north to the
south between the latitudes 20 to 45 degrees north. Although most of Japan belongs to the temperate
monsoon zone, the northern island of Hokkaido lies in a sub-arctic zone and a subtropical climate
prevails in the southern edge of the South-western and Ogasawara islands. Ocean currents and
prevailing westerly winds contribute to a diversity of climatic conditions. While codling moth is
prevalent throughout the temperate zone, the pest has not been discovered in Japan.
2.8 There is no dispute between the parties that Japan is free of codling moth and that it is a pest
of quarantine significance to Japan.
2. Methyl bromide
2.9 The Montreal Protocol on Substances that Deplete the Ozone Layer (the "Montreal Protocol")
requires developed countries to phase-out the production and importation of methyl bromide
beginning in 1999 and ending, with a total phase-out, on 1 January 2005. Developing countries will
freeze the production and importation of methyl bromide as of 1 January 2002 and begin a step-down
reduction in 2005, with total phase-out by 2015. US law currently calls for a phase-out of methyl
bromide production and importation by 1 January 2001.
2.10 Notwithstanding the above, the use of methyl bromide for quarantine and pre-shipment
applications is exempted from the phase-out schedule.
5 The US Administration has expressed
willingness to consult with the US Congress on changes to US law if alternatives do not exist for
control of key pests as the 2001 phase-out date approaches.
3. Technical and scientific terms used in the parties' submissions
CxT value (Concentration times time)
2.11 The CxT value for a fumigation is an expression of the relationship between fumigant gas
concentration and time in the fumigation enclosure or chamber. It is an expression of the active gas
dosage to which the pest or test organism is exposed during the time of the treatment. Because the
concentration decays during the fumigation time, "concentration" is an average value derived from a
number of measurements and requires temperature, load and humidity to be specified for proper
definition.
Dose-mortality test (DMT)
2.12 The dose-mortality test is an experimental pro cedure in which the response of an organism is
estimated for a series of mortality-inducing doses of a specified treatment. Where possible, individual

5 Article 2H:6 of the Montreal Protocol.

dose-mortality tests target a specific stage of an organism as the susceptibility to a treatment can vary
between life stages. The main purposes of dose-mortality testing are to produce data for analysis used
for the determination of parameters categorizing the response of an organism, and the comparisons of
efficacies of different treatments. In developing quarantine treatments against codling moth for
products exported to Japan, dose-mortality testing is used to produce data for analysis for the
determination of the least vulnerable stage of the pest and the prediction of a treatment dose to meet a
required level of efficacy. The target organism test unit is usually a sub-sample of 20 – 50 insects; the
test is typically replicated three times, at each dose level. For a satisfactory result, five or more dose
levels are usually required, evenly spaced between 0 and 100 per cent mortality.
Fumigation
2.13 To kill pathogens or insects by using gas or fumes. A fumigant is a pesticide which acts upon
the target pest as a gas. For the purposes of this report, the fumigant is methyl bromide (MB), and
"MB treatment" refers to fumigation with methyl bromide.
Probit analysis, LD (lethal dose) and probit 9
2.14 Probit analysis is a biometrical technique for analysis of experimental data in which the
quantitative response of an organism, usually expressed as mortality, is subjected to regression
analysis with respect to treatment dose. Mathematical transformation of mortality to probability units,
termed "probits", assists in conversion of the normal distribution (curve) of the response data to a
linear distribution to facilitate analysis. Dose data is frequently, but not invariably, logarithmically
transformed for the same purpose of linearity. The outcomes of probit analysis are values such as LD
(lethal dose), LC (lethal concentration) or LT (lethal time) for a nominated proportion of the
population (for example, 50 per cent or 99.99 per cent), together with nominated confidence or
fiducial intervals (for example, 95 per cent).
6 The main purposes of probit analysis are (i) to define
susceptibility of a population of target organisms to a treatment in terms of LD, LC or LT values; (ii)
subsequent comparisons of susceptibility of populations of target organisms, varying response
according to substrates, or treatment; and, (iii) the prediction of the dose required for a specific level
of treatment efficacy.
2.15 Probit 9 is equivalent to a target level of mortality, or level of treatment efficacy, of 99.9968
per cent mortality.
Sorption
2.16 The sum of adsorption, absorption and chemisorption. Adsorption is a physical surface effect
and results from the attraction of molecules to the surface of products 7 and other materials in the
fumigation chamber. Absorption is also a physical process whereby the chemical enters into the
product and other materials in the fumigation chamber. Chemisorption is an irreversible reaction in
which residues are left in the fumigated products and materials. When the pest takes in the fumigant
while in a product, or takes in the fumigant while on the surface of the fruit, it may die.

6 Dr. Heather referred to: Steel, R.G.D. and Torrie, J.H., Principles and Procedures of Statistics with Special
Reference to the Biological Sciences, McGraw-Hill (1960) p.22.
7 In this report the word "product" is used instead of "commodity" or "species".

Variety
2.17 A category within a species, based on some hereditary difference.8
B. JAPAN'S PLANT PROTECTION LAW AND THE ENFORCEMENT REGULATION
1. General
2.18 The legislation relevant to this dispute is contained in the Japanese Plant Protection Law,
enacted on 4 May 1950, as amended (the "Plant Protection Law"). 9 The applicable regulation is the
Plant Protection Law Enforcement Regulation (the "Enforcement Regulation"), enacted 30 June 1950,
as amended.
10
2.19 The stated objective of the Plant Protection Law is to ensure the "stabilization and
development of agricultural production by inspecting export plants, imported plants and domestic
plants, by controlling injurious animals and plants, and by preventing the outbreak or spreading
thereof".11
2.20 The Plant Protection Law identifies as "quarantine pests" those pests whose existence has not
been confirmed in Japan, or those which exist in part of the Japanese territory and are subject to
official control (Article 5.2 of the Plant Protection Law). Subsequent to such identification, the Plant
Protection Law establishes an inspection mechanism for imported plants and plant products:
(a) all imported plants and plant products have to be accompanied by a phytosanitary
certificate, in principle, which states that the plants and plant products are considered
free from the quarantine pests (Article 6, paragraph 1 of the Plant Protection Law);
(b) in certain cases, a growing-site inspection by the foreign authorities is mandatory
(Article 6, paragraph 2). This mechanism was introduced by the 1996 amendment of
the Plant Protection Law, and took effect April 1998;
(c) upon entering the Japanese territory, plants and plant products have to be inspected
by plant quarantine officers at one of the 101 major ports (or airports) of entry
designated by the Enforcement Regulation (Article 6, paragraph 3; Article 8,
paragraph 1); and,
(d) certain plants may be subjected to post-entry inspection at a post-entry quarantine
station for viruses and other pests which might not be detected by the visual
inspection at the ports of entry (Article 8, paragraph 7) .

8 Webster's Encyclopaedic Unabridged Dictionary of the English Language, 1996 Random House. The
International Convention for the Protection of New Varieties of Plants of 2 December 1961, Article 1, (vi) defines "variety"
as: "[A] plant grouping within a single botanical taxon of the lowest known rank, which grouping, irrespective of whether
the conditions for the grant of a breeder’s right are fully met, can be – defined by the expression of the characteristics
resulting from a given genotype or combination of genotypes, - distinguished from any other plant grouping by the
expression of at least one of the said characteristics and – co nsidered as a unit with regard to its suitability for being
propagated unchanged ….".
9 Law No. 151 of 1950; most recently amended in 1996. (Japan, Exhibit 6)
10 MAFF Ordinance No.73 of 1950. (Japan, Exhibit 7)
11 The Plant Protection Law, Article 1.

2.21 If a plant or a plant product fails to pass the above inspection, it will either be destroyed or
disinfected/disinfested under the Plant Protection Law. In order to counter the risk of inadvertent
introduction of particularly harmful quarantine pests, the Plant Protection Law delegates to the
Ministry of Agriculture, Forestry and Fisheries ("MAFF") the authority to prohibit importation of
certain host plants from countries or areas infested by the pests (Article 7, paragraph 1, item 1).
12
This authority is exercised in the form of a list of prohibited products, which is contained in a table
annexed to the Enforcement Regulation.
13 This "Annexed Table" identifies the quarantine pest which
constitutes the cause of the import prohibition, the countries or areas from which importation is
prohibited, and the prohibited host plants and their specific parts.
2.22 In practice, the confirmation process for efficacy of disinfestation treatment consists of two
parts: the process applicable to the initial lifting of the import prohibition and the test for the approval
of additional varieties. These are contained in two sets of guidelines developed in 1987 and which
have, to date, not been published – although they are available to interested parties. 14 The contents of
these are summarized below.
2. Initial lifting of prohibition
2.23 The "Experimental Guideline for Lifting Impor t Ban - Fumigation" ("Guidelines for initial
lifting") outline the procedure applicable to the initial lifting of the prohibition. The procedure
includes the following:
Basic Tests (small-scale dose-mortality tests)15
(a) Determination of the most resistant stage of insects to fumigation (a comparative test
of susceptibility between development stages) estimated through small-scale dose-
mortality tests.
(b) Estimation of treatment schedule achieving 100 per cent mortality.
Large-Scale Mortality Test
The efficacy of the chosen treatment is tested using 30,000 insects at the most
resistant stage on the variety (the representative variety). Japan accepts the efficacy
of the treatment if no insect survives, as an approximation of probit 9.
On-site confirmatory test
The results of the test are further confirmed on site by Japanese experts in the on-site
test using 10,000 sample insects (on the representative variety).

12 In addition, the Plant Protection Law prohibits the importation of quarantine pests, soil or plants contaminated
by soil and packages containing these articles (Article 7, paragraph 1, items 2 to 4).
13 List of the Plants Subject to Import Prohibition, Plant Protection Law Enforcement Regulation Annexed Table 2.
(Japan, Exhibit 8)
14 Contained in Japan, Exhibit 10.
15 A glossary of technical and scientific terms is contained in paragraphs 2.11 to 2.17.

3. Lifting of prohibition for additional varieties
2.24 The guidelines for the approval of additional varieties are set out in "Experimental Guide for
Cultivar Comparison Test on Insect Mortality – Fumigation". These include:
Basic test (small-scale dose-mortality test)
As the most resistant development stage of the insect is identified when (part of) the
species is approved for the first time, this test targets only the comparative efficacy
between the approved varieties and the newly proposed varieties. Response of insects
in additional varieties is tested for different levels of treatment (e.g., the amount of
fumigant, the length of cold treatment). The results are typically analyzed by
comparing LD
50 by probit analysis. If the new varieties are found to show equivalent
or superior effectiveness compared to approved varieties, no large-scale mortality test
is necessary. If the result is significantly less effective, however, a new treatment
standard has to be developed and tested by a large-scale experiment.
On-site confirmatory test
This test is performed on one representative variety. Japanese experts are sent to
confirm the on-site test.
TABLE 1
Test Schedule for Initial and Additional Lifting
Tests
(purpose)
Initial lifting
of prohibition
Lifting of
prohibition for
additional varieties
Test
insects
Subject varieties
Dose-response
(1) identification of the
most resistant
development stage of
the pest; and
(2) identification of the
representative variety
16
2,000 in total (200
per one dose
bracket times five
dose brackets in
two replicates)
ALL YES (for (1) and
(2))
YES (for (2))
Large-Scale
Confirmation of
efficacy
30,000 (10,000
each in three
replicates)
ONE YES NO*
On-Site Confirmatory
Final confirmation
10,000 ONE YES YES
* This assumes that the existing treatment would be found by basic tests to be adequate for new varieties. If not, a new treatment would
have to be established and confirmed by large-scale tests.

16 See paragraph 2.23 (under Large-Scale Mortality Test).

C. RELEVANT INTERNATIONAL STANDARDS, GUIDELINES AND RECOMMENDATIONS - THE IPPC
1. General
2.25 The SPS Agreement makes reference, in a number of provisions, to the "relevant international
standards, guidelines and recommendations". Annex A:3(c) of the SPS Agreement states that the
international standards, guidelines and recommendations relevant for plant health are those developed
under the auspices of the Secretariat of the International Plant Protection Convention ("IPPC" or "the
Convention") in cooperation with regional organizations operating within the framework of the IPPC.
2.26 The IPPC is an international treaty deposited and administered by the Food and Agriculture
Organization of the United Nations (FAO) but implemented through the cooperation of member
governments and Regional Plant Protection Organizations. The IPPC currently has 106 contracting
parties.
2.27 The purpose of the Convention is to secure common and effective action to prevent the spread
and introduction of pests of plants and plant products, and to promote appropriate measures for their
control. An important role of the IPPC is that of standard-setting.
2.28 The first text of the international convention was drafted in 1929 and came into force in 1952,
adopted by the FAO Conference one year prior to that. Amendments were adopted by the FAO in
1979 and the revised text came into force in 1991. In response to the role of the IPPC in the context
of the Uruguay Round and the negotiation of the SPS Agreement, the FAO established a Secretariat
for the IPPC in 1992, followed by the formation of the Committee of Experts on Phytosanitary
Measures (CEPM) in 1993. Negotiations for ame ndments to the Convention, in order to reflect
contemporary changes, particularly in light of the SPS Agreement, started in 1995 and were finalized
in 1997 when the FAO Conference adopted the New Revised Text of the IPPC. The New Revised
Text makes provision for the formation of a Commission on Phytosanitary Measures. The amended
IPPC will come into force upon ratification by two-thirds of its contracting parties.
2. Guidelines for Pest Risk Analysis
2.29 Generally, IPPC standards have their origin in national or regional initiatives, and/or are
drafted by expert groups organized by the IPPC Secretariat. The topics and priorities for draft
standards are determined by the Secretariat in consultation with Regional Plant Protection
Organizations and their members. IPPC standards fall within two categories: reference standards and
other standards.
2.30 Among the IPPC's completed standards is the Guidelines for Pest Risk Analysis ("PRA
Guidelines"), adopted in 1995.
17 The IPPC describes the PRA Guidelines as consisting of three
stages. Stage one involves (a) the identification of a pathway, usually an imported product, that may
allow the introduction and/or spread of quarantine pests, and (b) the identification of a pest that may
qualify as a quarantine pest. Stage two considers the identified pests individually and examines, for
each one, whether the criteria for quarantine pest status are satisfied, that is, that the pest is of
"potential economic importance to the area endangered thereby and not yet present there, or present
but not widely distributed and being officially controlled". Finally, based on the information gathered
under Stages one and two, Stage three determines the appropriate phytosanitary measure(s) to be
adopted. This pest risk management to protect the endangered areas should be proportional to the risk
identified in the pest risk assessment. The three stages are summarized in the PRA Guidelines as:
"initiating the process for analysing risk", "assessing pest risk" and "managing pest risk", respectively.

17 International Standards for Phytosanitary Measures, Guid elines for Pest Risk Analysis, FAO Publication No.2.
(US Exhibit 5)

2.31 Pest risk management options include18:
(a) inclusion in list of prohibited pests;
(b) phytosanitary inspection and certification prior to export;
(c) definition of requirements to be satisfied before export (e.g. treatment, origin from
pest-free area, growing season inspection, certification scheme);
(d) inspection at entry;
(e) treatment at point of entry, inspection station or, if appropriate, at place of
destination;
(f) detention in post-entry quarantine;
(g) post-entry measures (restrictions on use of product, control measures); and,
(h) prohibition of entry of specific products from specific origins.
2.32 Pest risk management options may also concer n ways of reducing risk of damage. The PRA
Guidelines state that the efficacy and impact of the various options in reducing risk to an acceptable
level should be evaluated in terms of the following factors
19:
(a) biological effectiveness;
(b) cost/benefit of implementation;
(c) impact on existing regulations;
(d) commercial impact;
(e) social impact;
(f) phytosanitary policy considerations;
(g) time to implement a new regulation;
(h) efficacy of option against other quarantine pests; and,
(i) environmental impact.
2.33 In sum, the PRA Guidelines define a procedure by which a pest risk analysis should be
performed, and lay down relevant factors which should be taken into account by the authorities in the
process.
III. CLAIMS OF THE PARTIES
3.1 The United States claimed that Japan's varietal testing requirement as it applied to quarantine
treatments for codling moth was an unjustified ba rrier to trade and was inconsistent with the SPS
Agreement. As a result of Japan's measure, main tained ostensibly for plant health ("phytosanitary")
reasons, Japan effectively blocked access to its market for US varieties that competed with a number
of Japanese produced varieties of the same product. The United States claimed that Japan's varietal
testing measure had failed each of the following obligations under the SPS Agreement in that it:

18 PRA Guidelines, p.20.
19 PRA Guidelines, p.20.

(a) was maintained without sufficient scientific evidence (Article 2.2);
(b) was not based on scientific principles (Article 2.2);
(c) was not based on an assessment, as appropriate to the circumstances, of the risks to
human, animal or plant life or health (Article 5.1);
(d) had not taken into account available scientific evidence; relevant processes and
production methods; relevant inspection, sampling and testing methods; prevalence
of specific pests; relevant ecological and environmental conditions; and quarantine
or other treatment (Article 5.2);
(e) was more trade-restrictive than required to achieve the appropriate level of sanitary or
phytosanitary protection, taking into account technical and economic feasibility
(Article 5.6);
(f) was not transparent in that one Enquiry Point was not responsible for the provision of
answers to all reasonable questions from interested Members regarding the measure
and there was furthermore no published source for the measure itself (Article 7); and,
(g) it was reliant upon control and inspection procedures, and applied to a modified
product (i.e. a different variety of a product), was not limited in its information
requirements to what was necessary for appropriate control and inspection
procedures, and was not limited to what was necessary to determine whether adequate
confidence existed that the product still met the regulations concerned (Article 8 and
Annex C).
3.2 In its request for consultations, the United States claimed that the fact that Japan's varietal
testing requirement was not a legitimate phytosanitary measure meant that it was also inconsistent
with Article XI of GATT 1994 and Article 4 of the Agreement on Agriculture. However, the United
States did not pursue these claims in its submissions or in its oral statements to the Panel, nor did it
request findings with respect to these claims.
3.3 Japan claimed that its policy was fully consistent with the relevant articles of the SPS
Agreement, Article XI of GATT 1994 and Article 4 of the Agreement on Agriculture. In particular,
Japan emphasized that the measure was entirely based on phytosanitary considerations and that the
suggestion by the United States to the contrary was false.
IV. ARGUMENTS OF THE PARTIES
A. T
HE SCOPE OF THE DISPUTE
4.1 The United States recalled that following the establishment of the Panel, Japan had raised
questions concerning the scope of the dispute. 20 The United States reiterated that the scope of the
dispute at issue, consistent with the request of the United States for the establishment of the Panel on
18 November 199721, was the prohibition by Japan of the importation of any variety of an agricultural
product on which Japan claimed that the pest codling moth might occur until such time as the variety
had been separately tested with respect to the efficacy of treatment with methyl bromide or treatment
with methyl bromide and cold storage.

20 This was contained in a letter from Japan to the Chairman of the Panel, dated 13 January 1998.
21 WT/DS76/2.

4.2 The United States noted that varietal testing applied to potential US fruit exports largely in
instances that involved codling moth. The facts submitted by the United States were therefore limited
to varietal testing of quarantine treatment efficacy against codling moth on certain products, using the
preferred treatment of MB fumigation or a two- component treatment of MB fumigation and cold
storage. The scope of the dispute thus concerned the prohibition by Japan on the importation of any
variety of an agricultural product on which Japan claimed the pest codling moth could occur until
such time as the variety had been separately test ed with respect to the efficacy of treatment with
methyl bromide or methyl bromide and cold storage.
4.3 In its first submission, Japan raised two issues in respect of the scope of the dispute: (1)
relevant provisions of the WTO agreements on which the complaining party’s claim was based, and
(2) the factual scope of the complaint. Japan argued that in its request for bilateral consultations22, the
United States had not clearly identified the relevant provisions and the covered agreements. The
United States had stated that relevant provisions "include, but are not limited to" Articles 2, 4, 5 and 8
of the SPS Agreement, Article XI of GATT 1994 and Article 4 of the Agreement on Agriculture. The
US request for the establishment of a panel had expanded the legal basis to "include, but are not
limited to" Article 7 of the SPS Agreement.
23 Thereafter, the first written submission of the United
States (of 19 February 1998) focused only on Articles 2.2, 5.1, 5.2, 5.6, 7 and 8, on Annex B,
paragraph 1, and on Annex C, paragraph 1 (c) and (h). Moreover, Japan noted that although the
United States referred to Article XI of GATT 1994 and to Article 4 of the Agreement on Agriculture
in a footnote, it did not even attempt to offer a prima facie case in that regard.
4.4 Japan argued that the Panel should find that the phrase "including but not necessarily limited
to" did not constitute part of its terms of reference
24 in light of the recent Appellate Body ruling in
India – Patent Protection for Pharmaceutical and Agricultural Chemical Products ("India -
Pharmaceuticals"), which held that the phrase failed to comply with the requirement under Article 6.2
of the DSU.25
4.5 Japan argued, furthermore, that the Panel should also eliminate Article 7 of the SPS
Agreement from the scope of its investigation, because that article was mentioned by the United
States for the first time in its request for establishment of a panel, and no consultation had been held
on that particular provision.
4.6 In regard to the description of the scope of the dispute by the United States, Japan requested
that the United States clarify if there was any fruit other than "apples, cherries, nectarines and
walnuts" which the United States believed was covered by the complaint. Japan noted that for those
four products there was no disagreement between the parties as to the efficacy of the current treatment
being applied to the approved varieties. Hence, if the scope of the dispute were limited to those fruits,
the matter before the Panel was a highly practical question of how effective the same treatment would
be for varieties which had not been approved so far. In addition, Japan requested the United States to
clarify if the scope of the examination by the Panel was limited to MB treatment or treatment with
methyl bromide and cold storage.
4.7 The United States claimed that Japan had misunderstood the Appellate Body Report on India
– Pharmaceuticals. In that report, the Appellate Body found that the use of the phrase "including but
not necessarily limited to" was "not sufficient to bring a claim relating to Article 63 [of the TRIPS

22WT/DS76/1.
23WT/DS76/2.
24WT/DS76/3.
25 WT/DS50/AB/R, adopted 19 December 1997, paragraph 90.

Agreement] within the terms of reference of the Panel". 26 Accordingly, the findings of the India -
Pharmaceuticals Report applied in a situation where a complainant made a claim with respect to a
provision of an agreement that was not identified in the request for a panel. 27 The current dispute did
not present the Panel with a similar situation. The United States had not made any claim with respect
to any provision of an agreement that had not been specifically identified in its request for the Panel at
issue. If at some time Japan were to believe that the United States had made such a claim, then Japan
could have presented its arguments to the Panel and the United States would have had the opportunity
to respond. The United States argued that Japan was seeking a finding in the abstract apparently based
on a hypothetical situation, a finding that furtherm ore would be inconsistent with the practice of
judicial economy supported by panels and the Appellate Body.
28
4.8 In respect of Article 7 of the SPS Agreement, the United States claimed that Japan was in
error in stating that no consultation was held on Article 7 of the SPS Agreement. In fact, Article 7
had been specifically mentioned in the US statement at those consultations. 29 In the course of the US
discussions with Japan concerning Japan’s measures at issue, and also considering Japan’s answers to
questions before the consultations, it became clear to the United States that these measures were not
transparent and were not clearly set forth anywhere. It was only in the consultations, where Japan
provided an oral explanation of the way in which some of its measures operated, that the United
States had been able to begin to understand the legal basis and scope of Japan’s measures.
4.9 The United States noted that a consultation request had to provide an "identification of the
measures at issue and an indication of the legal basis for the complaint" (DSU Article 4.4). However,
nothing in the DSU required that a Member had to ascertain all of the possible legal claims and
relevant provisions of the WTO agreements before the Member could even request consultations. In
this context, the United States noted that the Panel in European Communities - Regime for the
Importation, Sale and Distribution of Bananas stated:
"[as to the argument that] consultations must lead to an adequate explanation of the
Complainants’ case, we cannot agree. Consultations are the first step in the dispute
settlement process. While one function of the consultations may be to clarify what the
case is about, there is nothing in the DSU that provides that a complainant cannot
request a panel unless its case is adequately explained in the consultations. …
Ultimately, the function of providing notice to a respondent of a complainant’s claims
and arguments is served by the request for establishment of a panel and by the
complainant’s submissions to that panel."
 30
4.10 The United States stated that one of the purposes of consultations was to foster a better
understanding of the relevant measures and concerns of the various Members in order to promote a
satisfactory adjustment of the matter. Consultations were often the first time that the Member
maintaining the measure provided a detailed description of the measure and relevant facts and legal
documents. Consultations were not a "dress rehearsal" or "moot court" for the panel process requiring

26 Ibid, paragraph 90.
27 The United States noted that it had been described in the Appellate Body Report on India - Pharmaceuticals as
"there is a failure to identify a specific provision of an agreement that is alleged to have been violated", WT/DS50/AB/R,
paragraph 91.
28 In this respect, the United States recalled the Appellate Body Report in United States - Measure Affecting
Imports of Woven Wool Shirts and Blouses from India, adopted 23 May 1995, p.18.
29 The United States referred to US Exhibit 31, p.5.
30 WT/DS27/R/USA, adopted 25 September 1997, paragraph 7.20.

Members to have worked out all of their claims and positions in advance and presenting them in the
consultations for the other side to practice its prepared responses.
4.11 The United States noted that the DSU reflected the difference between requests for panels and
requests for consultations by using different terms for each. With respect to panels, the DSU required
that a request for the establishment of a panel provide a "brief summary of the legal basis of the
complaint sufficient to present the problem clearly". 31 However, with respect to consultations, the
DSU merely required that requests for consultations give "an indication" of the legal basis for the
complaint.
32 Moreover, if a matter had indeed been discussed in consultations, as had been the case
with respect to the US claim under Article 7 of the SPS Agreement, the responding party had even
less basis to claim unfair surprise. For the above reasons, there was no basis for the Panel to find that
the US claim under Article 7 of the SPS Agreement fell outside the scope of the panel proceeding.33
4.12 The United States reiterated that the dispute covered the prohibition by Japan on the
importation of any variety of an agricultural product on which Japan claimed that the pest codling
moth could occur. In this regard, the United States noted that Japan was best positioned to provide a
comprehensive list of products to which its measures applied. Due to the lack of transparency of
Japan’s measures, the United States had had difficulty in ascertaining the full range of agricultural
products involved. According to the "List of Plants Subject to Import Prohibition" submitted by
Japan in response to US questions in connection with the consultations, the United States understood
that Japan’s varietal testing requirements, as they pertained to the pest codling moth, also applied to at
least the following products: "apricot, cherry, ... plum, pear, quince and peach, ... and apple, ... and
fresh fruits and nuts in shell of walnut".
34 The United States requested further clarification from Japan
as to whether there were other products that were or could be subject to this import prohibition. For
the purposes of the dispute at issue, the relevant treatments were treatment with methyl bromide or
treatment with methyl bromide and cold storage.
4.13 Japan explained that the Japanese Government had long since published in the Official
Gazette the list of plants subject to import prohibition, namely eight plant products which were host
plants of codling moth: apricot, plum, pear, quin ce, apple, walnut, peach including nectarine and
cherry. However, Japan maintained that from a practical point of view, the products to be covered by
the current Panel had to be limited to four: apples, cherries, nectarines and walnuts. Japan noted that
no data had been provided nor any mention been made of any product other than these four products
in the US submissions; hence, the other four products should be excluded from the scope the dispute.
4.14 The United States noted that while it had thus far referenced only four products for which it
had negotiated entry on some varieties - apples, cherries, walnuts and nectarines - the principles that
applied to these products applied equally to the other four products named in the relevant regulation.
The United States had an interest in exporting to Japan also plums, pears, quince, peaches and apricots,
and had, in fact, requested permission to export to Japan one variety of plum s. The omission of the

31 Article 6.2 of the DSU.
32 Article 4.4 of the DSU.
33 In this respect, the United States agreed with the findings of the Panel in European Communities - Regime for
the Importation, Sale and Distribution of Bananas : "Consultations are, however, a matter reserved for the parties. The DSB
is not involved; no panel is involved; and the consultations are held in the absence of the Secretariat. In these circumstance s,
we are not in a position to evaluate the consultation process in order to determine if it functioned in a particular way. Whil e
a mutually agreed solution is to be preferred, in some cases it is not possible for parties to agree upon one. In those cases, it
is our view that the function of a panel is only to ascertain that consultations, if required, were in fact held or, at least,
requested". (WT/DS27/R/USA, paragraph 7.19)
34 Japan clarified that the term "fresh fruits" related sole ly to walnuts. Furthermore, nectarine was a variety of
peach, this was subsequently confirmed by all three experts advising the panel – therefore the term: "peaches, including
nectarines" (Section VI of this report deals with the Panel's consultation with scientific experts).

latter products from the debate had only to do with th e fact that these had not yet been proposed for
export to Japan. Japan’s measure was an import prohibition or restriction with respect to these products
as well, and the United States had specifically incl uded in its claims all products subject to Japan’s
measure. Moreover, unlike cherries, nectarines and walnuts, Japan had not pointed to a scientific study
regarding any of these other products - presumably because there were no studies that supported its
theory of variety affecting efficacy of treatment.
4.15 The Panel made a preliminary ruling on these matte rs at its first substantive meeting with the
parties on 2 April 1998. The ruling is contained in paragraph 8.4.
B. THE MEASURE AT ISSUE
4.16 The United States alleged that Japan imposed an absolute ban on all products that Japan
asserted were potential hosts to a quarantine pest such as codling moth. The Japanese legislation
which was applicable imposed an import ban on enumerated "prohibited articles"; this was the Plant
Protection Law (described under paragraph 2.18), enacted on 4 May 1950, as amended. The only
applicable regulation was the Enforcement Regulation, enacted 30 June 1950, as amended. No
legislative or regulatory provision specifically described or imposed a requirement of varietal testing
to obtain an exemption from such a ban. 35 The practice of varietal testing was not formally written in
any law or regulation, but stemmed from the implem entation of the aforementioned legislation and
regulation.
4.17 The United States noted that Article 7 of the Plant Protection Law specified which products
were prohibited for importation; these included "quarantine pests". The annex to Article 9 of the
Plant Protection Law Enforcement Regulation specified the pest species that were subject to
quarantine, the country(ies) or region(s) from which the pest originated, and the plant species that
Japan asserted to be potential hosts to the quarantine pest. The annex listed the plants prohibited
from entry, and an appendix to the list also indicated which varieties of products from specified
regions were permitted entry into Japan. The Un ited States maintained that the regulation was
otherwise unclear on the question of how a particular variety might be permitted entry.
4.18 As it had evolved through practice, the ban was lifted only for specific varieties of an
identified host product upon satisfaction of "quarantine treatment standards established through a
regime of basic testing ... to prove complete mortality of the most resistant stage of the relevant pest in
the scale of more than 30,000 test insects being used".
36 "The disinfestation test with a scale of
30,000 test insects is to seek for a disinfestation rate equivalent to probit 9 (99.9968 per cent
mortality) which was adopted by the Unit ed States in its treatment standard." 37 To satisfy this
requirement for permission to export a new variety, Japan required elaborate and repetitive testing
procedures, and a public hearing process.38
4.19 The United States acknowledged that the SPS Agreement recognized that countries had a
sovereign right to implement legitimate restrictions on trade to protect their plant life and health from
the introduction of pests that might cause harm. However, the United States stressed that the SPS

35 According to the United States, Japan had confirmed this under Question 2 of Japan's Response to US
Consultation Questions (US Exhibit 3), in which Japan stated: "Lifiting of im port bans by variety is based on the legislation
tabulated below. There is no situation where lifting of import bans by variety is based on legislation other than that given
below". The table referred to listed the Plant Protection Law and the Enforcement Regulation.
36 Japan's response to Question 5 of US Consultation Questions. (US Exhibit 3)
37 Japan's response to Question 8 of US Consultation Questions. (US Exhibit 3)
38 Japan's responses to Questions 5 and 8 of US Consultation Questions. (US Exhibit 3)

Agreement did not permit unjustified import prohibitions that did not address legitimate phytosanitary
concerns. The Japanese requirement of varietal testing was exactly the kind of unnecessary and
unjustified measure that the SPS Agreement was intended to prohibit.
4.20 The history of US efforts to export apples, cherries, walnuts, and nectarines illustrated the
way in which the Japanese insistence on varietal testing had served as a significant barrier to trade.
Since the early 1970s
39, the United States had been engaged in a rigorous research effort to export
various fruit products to Japan. An effective quarantine treatment 40 for cherries had first been
developed in the United States in 1976; for US walnuts in 1984; for US nectarines in 1986; and an
effective treatment for US apples had first been developed in 1986.
TABLE 2
History of Japanese Approval Process for Varietal Testing on US products
Product Date
Treatment
Developed*
Testing Process
Began
Confirmatory
Test Dates
Public Hearing
Date**
Approval Date
APPLES
Red Delicious 1986 Oct. 1969 17-29 April
1994
7 and 8 July
1994
22 August 1994
Golden Delicious 1986 Oct. 1969 17-29 April
1994
7 and 8 July
1994
22 August 1994
Gala 1986 Oct. 1994 4 Sept. - 26
Nov. 1997
Pending Pending
Granny Smith 1986 Oct. 1994 4 Sept. - 26
Nov 1997
Pending Pending
Jonagold 1986 Oct. 1994 4 Sept. - 26
Nov 1997
Pending Pending
Fuji 1986 Oct. 1994 4 Sept. - 26
Nov 1997
Pending Pending
Braeburn 1986 Oct. 1994 4 Sept. - 26
Nov 1997
Pending Pending
CHERRIES
Bing 1976 1973 1977 10 January 1978
Van 1976 1973 1977 10 January 1978

39 Moffitt, "Methyl Bromide Fumigation Combined with Stor age for Control of Codling Moth in Apples," 64(5) J.
Econ. Entomol. pp. 1258-1260, 1971. (US Exhibit 21)
40 The United States noted that the development of an effective treatment meant that probit 9 security was achieved
during large-scale tests of 30,000 codling moths.

TABLE 2
History of Japanese Approval Process for Varietal Testing on US products
Product Date
Treatment
Developed*
Testing Process
Began
Confirmatory
Test Dates
Public Hearing
Date**
Approval Date
Lambert 1976 1973 1977 10 January 1978
Rainier 1976 June 1988 July 1991 12 May 1992
Garnett 1976 June 1993 9 May – 10
June 1994
18 January 1995
Brooks 1976 May 1994 13 May 14
June 1994
25 October 1996
Tulare 1976 May 1994 13 May - 14
June 1994
25 October 1996
Sweetheart 1976 August 1995 24 July - 18
Aug 1997
Pending Pending
Lapin 1976 August 1995 24 July - 18
Aug 1997
Pending Pending
NECTARINES
Summer Grand 1986 July 1986 July 1986 17 June 1988
Fantasia 1986 July 1986 July 1986 17 June 1988
May Grand 1986 June 1986 June 1986 17 June 1988
Spring Red 1986 June 1986 June 1986 17 June 1988
Fire Brite 1986 June 1986 June 1986 17 June 1988
Red Diamond 1986 June 1986 June 1986 1 March 1995
May Diamond 1986 June 1988 June 1988 December 1990
May Fire 1986 May 1988 May 1988 December 1990
May Glo 1986 May 1988 May 1988 December 1990
Royal Giant 1986 August 1992 August 1992 1 March 1995
WALNUTS
Hartley 1984 1982 August 1984 1986
Payne 1984 1982 August 1984 1986
Franquette 1984 1982 August 1984 1986
Eureka 1984 1982 August 1984
* Development of an effective treatment means that probit 9 security was achieved during large-scale tests of 30,000 codling
moths.
** Absence of public hearing date denotes only that the information is not available.
Source: USDA Agricultural Research Service, USDA Animal and Plant Health Inspection Service (US Exhibit 1)
4.21 The United States noted that Japan was a major producer and consumer of apples - the twelfth
largest producer in the world. In 1995-1996, Japan had produced for commercial use 879,100 metric

tons of apples, and consumed 796,883 metric tons of apples. Imports accounted for less than one
percent of that consumption (1,089 metric tons).41
4.22 The United States claimed that as a consequence of Japan's unjustified trade restrictions,
exports to Japan of cherries, nectarines, apples and walnuts currently represented only a small part of
US exports world-wide. In 1996, US apple exports totalled US$409.49 million. Only 0.14 per cent of
those exports (US$570,000) went to Japan. Of the total US$78.85 million nectarine (and peach)
exports in 1996, only 0.26 per cent (US$185,000) were exported to Japan. In respect of walnuts,
18.91 per cent of US exports went to Japan. While a significant amount of US cherry exports were
sent to Japan (61.91 per cent of US exports), this number was not as significant when compared to the
number of cherry varieties that were not even considered for export to Japan because the testing of
quarantine treatment for each variety would be overly burdensome.
4.23 It was common practice, according to the United States, to produce new varieties of
agricultural products and enhance existing ones to capture a particular preference in the market place,
or to modify harvesting time to coincide with demand trends for that fruit. These changes and
enhancements could be as benign and subtle as a variation in the color of the product. The
modifications of the product represented the sort of variability that did not affect how effective the
quarantine treatment would be at killing the plant pests of concern. Yet Japan required complete
testing and review of each variety, no matter how similar the variety might be to already accepted
varieties. The entire testing and approval process for a given variety took anywhere from 2 to 4 years
to complete, and was expensive to perform.
42 As a result, the United States claimed that Japan's
measures served to restrict or altogether block access to Japan's market for new varieties.
4.24 The United States claimed that efficacy of MB treatment for apples, cherries, walnuts and
nectarines had been conclusively established. Japan was obliged to allow importation of all US
varieties of these products without delay, subject only to application of the respective protocol of
treatment for the product.
43
4.25 Japan noted that the importance of phytosanitary measures to protect plants against foreign
pests had long been recognized under the IPPC (paragraphs 2.25 to 2.33), to which Japan had been a
party since 1952. While codling moth was prevalent throughout the temperate zone, the pest had not
been discovered in Japan (paragraph 2.6). It was Japan's opinion that, to a considerable extent, this
was attributable to Japan's plant quarantine policy. For Japan, (i) the diverse and mild climatic
conditions surrounding Japanese agriculture, which allowed for a high risk of the establishment of
exotic pests once they were introduced into the country; (ii) the highly concentrated, intensive
cultivation, which would be seriously damaged once pests were established; and, (iii) the recent
increase in the volume and diversity of plant/agricultural imports, made international plant quarantine
essential to Japan. Hence, in order to prevent the entry of quarantine pests, the Plant Protection Law
and the Enforcement Regulation identified quarantine pests, and prescribed inspection, disinfestation
and other quarantine measures.
4.26 Japan contended that the exercise of the authority of import prohibition was kept to the
minimum necessary on the basis of available scientific evidence. Specifically, the import prohibition
applied only to host plants of the quarantine pests which were found to pose a particularly significant
risk, as a result of the risk assessment conducted in compliance with the PRA Guidelines of the FAO

41 USDA, Economic Research Service.
42US Exhibit 1.
43 The United States referred to the work plans for cherries, nectarines, and apples. These indicated a thoroughness
in testing procedures that would be applied consistently to any product that was subject to quarantine. (US Exhibit 22)

(paragraph 2.30), and against which no inspection would be effective. Currently these high-risk
quarantine pests were 12 species of insects44, three diseases45 and pests of rice not found in Japan.
4.27 Japan stated that prohibited plants, countries or areas of origin and the quarantine pests
concerned were subject to continuous review whenever additional information became available in
respect of the introduction of a pest into a new area, its eradication, new discoveries on pests and
hosts, or development of a risk analysis method. Most recently, Japan had reviewed the regulations in
April 199746, on the basis of the PRA Guidelines, and, as a result, the sweet potato vine borer had
been deleted from - and fire blight had been added to - the quarantine pests whose host plants were
subject to import prohibition.47
4.28 Japan recalled that the MAFF had the authority to lift the import prohibition. This was done
by the de-listing of the product from the Annexed Table to the Enforcement Regulation (an
amendment of the Enforcement Regulation). This was, according to Japan, the subject matter at issue
in the current dispute (characterized by the United States as "varietal testing"). Japan claimed that
contrary to the arguments of the United States, the import prohibition was not absolute (paragraph
4.16). The Japanese Government had accommodated foreign governments’ requests for lifting of the
prohibition. The number of products de-listed from the ban was evidence of this. The criteria
established through past practice for de-listing were the following:
(a) lifting was subject to a proposal of an alternative measure by the foreign government;
(b) the level of protection required of the measure was that equivalent to import
prohibition; and,
(c) the exporting government bore the burden of proving that the proposed measure
achieved the required level of protection.
4.29 In respect of the first criteria, Japan claimed that an active measure was necessary to counter
the quarantine pest, because inspection did not work effectively against the pest. Such a measure
could be: complete eradication of the pest from the territory, establishment of a pest-free area, or
disinfection/disinfestation treatment prior to ship ment. The purpose of involvement of the foreign
government was to ensure implementation of the measure in the foreign jurisdiction. In respect of the
second criteria, the requirement of equivalency was self-explanatory; Japan noted that the parties to
the dispute at issue were not in conflict over the level of protection. Third, for practical reasons, the
importing country was at a disadvantage in respect of the gathering of sufficient information on exotic
pests (which did not exist domestically), for varieties that often were not produced in Japan, hence,
the exporting government had the burden of proving that the proposed measure achieved the required
level of protection.
4.30 Japan claimed that these criteria had been designed as part of the policy for the
implementation of domestic law through past practice . They represented fundamental policy
orientation and were not published as a document. However, for the key process of demonstration of

44 (i) Codling moth; (ii) Mediterranean fruit fly; (iii) Bactrocera dorsalis species complex: (iv) Queensland fruit
fly; (v) melon fly; (vi) sweet potato weevil; (vii) West Indian sweet potato weevil; (viii) Colorado potato beetle; (ix)
potato cyst nematode; (x) white potato cyst nematode; (xi) citrus burrowing nematode and (xii) Hessian fly.
45 Potato wart, tobacco blue mold and fire blight.
46 Japan noted at the first substantive meeting that amended regulations were effective as of 1 April 1998.
47 Japan noted, in addition, that in light of the latest information on the insect classification, the Oriental fruit fly
was reclassified as the Bactrocera dorsalis species complex, and the white potato cyst nematode was separated from the
potato cyst nematode.

efficacy of quarantine treatment, MAFF had developed test guidelines in order to enhance
transparency and these were made available for exporting countries.
4.31 The description of the Japanese practice by the United States was misleading (paragraphs
2.18 to 2.24). Japan did not demand "complete testing and review of each variety" (paragraph 4.23),
the requirement depended on the US export strategy. If the United States proposed to export more
than one variety, complete testing including a large- scale test (30,000 test insects in three replicates)
would be required on only one representative variety. That is, if the United States were to apply for
approval of 100 varieties of the same product, co mplete testing would be required only of the one
variety which demonstrated the lowest degree of sensitivity to the proposed treatment in dose-
mortality tests and a probit analysis. The concept of a representative variety applied equally to
approval of additional varieties. As long as ef ficacy of the treatment in use was confirmed with
respect to additional varieties by dose-mortality tests, what was required was an on-site confirmatory
test (10,000 test insects) for one representative variety alone. Even if the results of dose-mortality
tests were unsatisfactory, a large-scale test was necessary for only one representative variety of the
additional varieties.
4.32 Japan maintained that the essence of the requirement was a demonstration that a proposed
treatment would be effective on all varieties which the exporting government proposed to ship to
Japan. The exporting government was free to propose any method for the purpose of this
demonstration.
4.33 Japan pointed out that what the United States had referred to as the testing procedure (in
paragraph 4.18) were the contents of the "Experimental Guidelines for the Lifting Import Ban" and
the "Experimental Guide for Cultivar Comparison Test on Insect Mortality"
48 which the MAFF had
provided as a model confirmation process for a proposed disinfestation treatment of insects. Japan
stressed that these were model guidelines, they did not have the force of law, and were not imposed by
the MAFF. Exporting governments were free to propose their own confirmation method.
4.34 Japan stated that the US data cited in paragraph 4.22 showed that Japan was the largest
importer of American cherries, and was a major (the largest, if members of the European
Communities were treated separately) importer of US walnuts.
4.35 According to the United States, to have the ban lifted on a new variety, the testing procedure
included: (i) an initial test to estimate the basic dose-response of the pest in question, in or on the
variety in question; (ii) data review by a MAFF official; and, (iii) a large-scale test consisting of a
total of 30,000 insects at 10,000 insects in each of three successive individual trials. If successful,
only then was an on-site confirmatory test conduct ed in the presence of MAFF staff. Resulting data
was again reviewed by a MAFF official, and following confirmation of efficacy, a public hearing in
Japan was required on lifting the ban for the particular variety. The United States noted that where
there was an accepted quarantine treatment for another variety of the same product, Japan allowed for
a comparison dose-mortality test. The same treatment was tested simultaneously on the new and old
variety and the results were compared to ascertain whether there were differences in response of the
insects. The results of this test were reviewed by Japanese officials. If there were no differences, then
an on-site confirmatory test was required with 10,000 insects generally divided into three replications,
in the presence of a MAFF official. This process was rarely employed, however, because it was
possible that the old variety was no longer cultivated or the harvest time for one variety did not
coincide with another.
4.36 In respect of the concept of representative variety, the United States noted that as a matter of
practical application of these tests, there were occasions where the United States would seek to
introduce more than one variety at the same time. Japan was correct in asserting that in some

48Contained in Japan, Exhibit 10.

circumstances, because of the varietal testing requirement, a representative variety could be chosen to
perform the confirmatory tests. But that did not mean that significant time and resources had not
already been devoted to dose-mortality testing on all of the proposed varieties. Dose-mortality testing
could take as long as a month or more to perform on a given set of varieties. It was also important to
bear in mind that the benefit of allowing for a representative variety was not always realized. This
was because it was difficult to test certain varieties simultaneously due to the fact that they were
harvested at different times. Moreover, with some fruit products, new varieties were developed so
rapidly and there were so many varieties that it was not practical to conduct this type of intensive
varietal testing. Thus, while not all of the varieties that had been tested by the United States had
undergone confirmatory testing, a large proportion of the varieties had; and more importantly, all
varieties had been subjected to some form of detailed testing.
4.37 In this respect, the United States noted that it had tested seven varieties of apples, nine
varieties of cherries, four varieties of walnuts and ten varieties of nectarines. There had never been a
difference in results from one variety to another. Every confirmatory test had uniformly achieved
Japan's level of quarantine protection against the codling moth at the same exact treatment level for a
product.
49 Moreover, Japan was not able to point to a single example in which any agricultural
exporting country in the world had had to modify a treatment for killing codling moth among varieties
of the same product. Japan had approved the treatments for ten varieties of nectarines, two varieties of
apples, seven varieties of cherries and three varieties of walnuts. This was despite differences in dose-
mortality tests and despite differing CxT values. Japan had approved these varieties because of the
ability of the United States to demonstrate that th e quarantine treatment provided the desired level of
mortality. Every article publis hed on the efficacy of MB and/ or MB and cold storage for
disinfestation of codling moth had demonstrated that there were no differences among varieties that
affected efficacy of a quarantine treatment.
4.38 Japan countered that large-scale demonstration (i.e., the large-scale confirmatory test or the
on-site confirmatory test) applied to one representative variety which was found, in dose-mortality
testing and the probit analysis, to be the most resistant to a treatment. Thus, contrary to what had been
suggested by the United States, the number of varieties which had been subject to either form of
large-scale demonstration had been: two varieties of apples (as opposed to seven as the United States
had claimed), seven varieties of cherries (as opposed to nine), one variety of walnuts (as opposed to
four) and three varieties of nectarines (as opposed to ten) (Table 3). Japan's policy was not such that
would require unnecessary testing on all varieties.

49 US Exhibit 2.

TABLE 3
History of Lifting and Large-Scale Demonstration of US Fruits
(i.e. either large-scale confirmatory test or on-site confirmatory test)
Approved Year Varieties Large-Scale Test On-site
Confirmatory
Test
Apples 1994 Red Delicious
Golden Delicious
Red Delicious Red Delicious
(under way) Gala
Braeburn
Jonagold
Fuji
Granny Smith
Fuji
Cherries 1978* Bing
Van
Lambert
Bing
Van
Lambert
Bing
Van
Lambert
1992 Rainier Rainier
1995 Garnet Garnet
1996 Brooks
Tulare Tulare
(under way) Sweetheart
Lapin
Sweetheart
Nectarines 1988 Summer Grand
May Grand
Fantasia
Spring Red
Firebrite
Red Diamond
May Grand May Grand
1993 May Diamond
Mayfire
May Glo
May Diamond
1995** Royal Giant Royal Giant Royal Giant
Walnuts 1986*** Franquette
Payne
Hartley Hartley Hartley
* At that time, each of the varieties was subjected to large-scale demonstration.
** The large-scale test was necessary because the element of the treatment was modified (fruit containers were changed from
wooden bins to export carton boxes).
*** The representative variety was selected by the CxT value.
4.39 Conversely, five varieties of apples (out of seven), seven varieties of nectarines (out of ten),
two varieties of cherries (out of nine) and two varieties of walnuts (out of three) had been, or were
being, approved by the small-scale laboratory experiment alone. It was therefore not correct to state
that "all varieties have been subjected to some form of detailed testing". On the contrary, the present
confirmation mechanism used the dose-mortality test to screen so that not all varieties needed to be
subjected to large-scale demonstration, either by the large-scale confirmatory test or the on-site
confirmatory test.

C. APPLICATION OF THE SPS AGREEMENT
4.40 The United States argued that the SPS Agreement applied to "all sanitary and phytosanitary
measures which might, directly or indirectly, affect international trade" (Article 1.1). In this sense,
Japan's measures were phytosanitary measures 50, as defined by the SPS Agreement in Annex A, and
directly or indirectly affected international trade.
4.41 According to the United States, the definition demonstrated that whether a measure was a
sanitary or phytosanitary measure depended on the purpose of the measure. Japan had stated that the
purpose of varietal testing was to protect plant life or health within Japan from the establishment and
spread of certain pests that could cause harm to its agriculture. 51 In order to export varieties to Japan,
the exporting country had to obtain certification that it had met Japanese requirements.
4.42 As the definition of a "sanitary or phytosanitary measure" in Annex A of the SPS Agreement
specifically listed "testing procedures" as being included in sanitary and phytosanitary measures,
Japan's measure at issue was a phytosanitary measure. The United States further argued that Japan's
measure was a "procedure to check and ensure the fulfilment of sanitary or phytosanitary measures"
(chapeau to Annex C of the SPS Agreement). In addi tion, the United States was of the view that as a
phytosanitary measure, it was subject to all of the requirements of Articles 2, 5, and 7 of the SPS
Agreement. As an Annex C measure, it was also subject to all of the requirements of Article 8 and
Annex C of the SPS Agreement.
4.43 Japan's measure applied to imports of certain agricultural products such as apples, cherries,
walnuts, and nectarines. It prohibited the importation of any agricultural product that had been
identified by Japan as a host to a quarantine pest. The ban was only lifted upon a showing that a
quarantine treatment for a pest achieved Japan's level of protection for each variety of the agricultural
product, irrespective of the fact that an effective quarantine treatment had been accepted for another
variety of the same product. Therefore, the Japanese requirement of varietal testing adversely
affected international trade.
4.44 Japan did not dispute that the measure at issue was covered by the SPS Agreement. Japan
argued that the requirement of demonstration of efficacy was consistent with international practice.
There was nothing in the SPS Agreement which prevented enforcement of that requirement.
D. B
URDEN OF PROOF
4.45 The United States claimed that Japan had failed to present "minimally sufficient evidence" as
to why variety mattered in regard to MB quarantine treatment. Instead, Japan insisted that the exporting
country had to provide evidence as to why variety did not matter. This was clearly contrary to the
obligations of the SPS Agreement. The United States a ccepted that it had the burden to establish a
prima facie case that the measure of varietal testing was inconsistent with the SPS Agreement In this
dispute, the United States maintained that it had shown that Japan's measure was not based on
scientific evidence and a risk assessment, that all available scientific and empirical evidence indicated
that differences among varieties did not affect efficacy of treatment against codling moth; that the
testing of efficacy of quarantine treatment by product alone achieved Japan’s level of protection
against the risk of entry, establishment and spread of codling moth; and that testing and treatment by
product was a significantly less trade restrictive measure available to Japan. The United States had

50 Relating to the protection of the life or health of plants.
51 In the Government of Japan's response to Question 2 of US Consultation Questions, Japan had stated that "GOJ
designates pests and diseases, which do not exist in Japan but which could conceivably cause serious damage to agriculture
if outbreak were to occur, and prohibits imports of their host plants". (US Exhibit 3)

met its burden of proof. As the Appellate Body in EC Measures Concerning Meat and Meat Products
("EC - Hormones") stated, "when the prima facie case is made, the burden of proof moves to the
defending party, which must in turn counter or refute the claimed inconsistency".52
4.46 Japan contended that the United States had not submitted any demonstration that the
proposed product-by-product approach would be effective for all varieties. The requirement of
demonstration, which was the exercise of domestic authority under the Plant Protection Law, was not
only reasonable in light of the disparity of information but was consistent with established
international practice. Furthermore, Japan noted that there was no disagreement between the parties
in this respect; the United States had accepted this principle in that it had stated that it was reasonable
for the importing country to require the exporting country to propose and substantiate the efficacy of an
approach that achieved the importing country’s level of phytosanitary protection (paragraph 4.50). There
was nothing in the SPS Agreement which prevented enforcement of the requirement of demonstration
as such; it was not per se inconsistent with the SPS Agreement. It was the responsibility of an
applicant to prove safety (or absence of harm) of a medicinal product, for example; it was not the
obligation of Member governments under the SPS Agreement to disprove safety. No Member
government of the WTO allowed the applicant the lu xury of obtaining governmental approval of a
drug, food additive or phytosanitary treatment simply because inefficacy and/or danger thereof had
not been proven. Nor was it Japan's obligation to scientifically demonstrate that varieties resulted in
different degrees of efficacy of a treatment by, for example, conducting large-scale tests at Japan's
expense. Such interpretation of the provisions of the SPS Agreement was tantamount to denial of the
requirement of demonstration by the exporting government. The issue was rather whether or not the
importing authorities had acted in conformity with the Agreement in perceiving the risk presented by
the eventual importation of a different variety. Japan claimed that there was data which suggested the
possible presence of varietal difference in efficacy of a treatment which gave rise to the concern.
Hence, the requirement under the SPS Agreement of scientific evidence or a risk assessment was fully
met. Insofar as the requirement of demonstration was thus consistent with the SPS Agreement, the
exporting government had to show, with scientific evidence, that a given treatment would be effective
for the proposed varieties.
4.47 Japan noted that it did not impose a particular measure, as long as a proposed alternative
method demonstrated efficacy equivalent to the import prohibition.
53 For instance, for lemons,
grapefruits and ponkan oranges, Japan had approved importation on a product-by-product basis
(although the relevant pest, fruit fly, and the relevant treatment, cold treatment, were not covered by
the terms of reference of the current dispute). This was because most of these citrus varieties had
been developed by somatic mutation, such as bud mutation, and their varietal differences were not
known to be significant.
4.48 Japan argued that the United States had not submitted any relevant evidence in this regard.
Nor had any convincing argument to support the abse nce of varietal differences been made. In order
for the United States position to prevail under Articles 2.2 and 5.1, it had to prove that the varietal risk
was either non-existent or insignificant in light of scientific evidence and/or a risk assessment. It was
not sufficient for the United States to prove that there were risks other than those resulting from
varietal differences including "natural variation". The United States had repeated arguments that (i)
laboratory test results were unreliable and that (ii) the existing treatment had been effective so far. In
doing so, the United States had failed to show that Japan was not abiding by the requirement of
scientific basis or evidence. Hence, Japan urged the Panel to apply the burden of proof principle
which was stated in the EC - Hormones case correctly. The United States had failed to make a prima
facie case.

52 WT/DS/26/AB/R, adopted 13 February 1998, paragraph 98.
53 MB fumigation, cold treatment, vapor heat treatment, dry heat treatment, phosphine fumigation and a
combination of these alternatives were an example of specific disinfestation measures which Japan had already approved.

4.49 The United States stressed that it was important not to confuse the fact that the exporter would
typically assume the burden of meeting the importing country's concerns with the question of the burden
of proof for dispute settlement purposes. The United States had always accepted that in the current
proceeding it bore the burden of presenting facts and arguments sufficient to establish a presumption that
Japan's measure was inconsistent with the cited WTO Agreements. However, this did not alter the fact
that Japan was required to have sufficient scientific evidence to maintain its measure and to base its
measure on a risk assessment. The United States had proven that Japan did not have sufficient scientific
evidence or a risk assessment to justify its assumption that variety mattered. The United States did not
need to prove that there were no varietal differences that mattered for purposes of treatment efficacy.
This was a fundamental issue of burden of proof under the SPS Agreement; in EC – Hormones, the
European Communities claimed that it could ban meat because it was not proven that there was no risk.
This approach had not been accepted by the Appellate Body.
4.50 The United States noted that as a general proposition, assuming that a product proposed for
export was indeed a potential host for a pest appropriately determined to be a pest of quarantine
significance, it was reasonable for the importing country to require the exporting country to propose and
substantiate the efficacy of an approach that achieved the importing country’s level of phytosanitary
protection. As Japan acknowledged, such a proposal could involve eradication of the pest from the
territory, establishment of a pest-free area, or a disinfestation treatment (paragraph 4.29). The United
States maintained, however, that such an approach could also involve integrated pest-management
practices and a systems approach, which did not necessarily involve a disinfestation treatment. Indeed,
the United States had long proposed integrated pest-management practices for codling moth in
conjunction with MB fumigation and, in the case of apples, cold treatment. The United States believed it
had established the efficacy of this approach for apples, cherries, nectarines, and walnuts.
4.51 In the absence of a recognized pest-free area, it was the experience of the United States that
Japan did not permit importation of any varieties of the relevant products without demonstration of the
efficacy of the applicable MB quarantine treatment for codling moth on each and every variety. This
rigid criterion for demonstration of efficacy was not a reasonable procedural requirement.
4.52 The United States noted that in connection with Japan's claims regarding lemons, grapefruits and
ponkan oranges, Dr. Ducom (an expert advising the Panel
54) had stated that there was no scientific basis
for distinguishing these products from the products at issue in considering whether product-based testing
was feasible. Further, the United States pointed out that the treatments developed for each product had
been uniformly effective for the entire commodity.
4.53 Japan noted in respect of integrated pest management or other techniques, that while they were
effective to reduce the level of infestation, they did not eliminate the risk of the pest to the level
equivalent to an import prohibition. Disinfestation had been chosen in the light of these considerations,
and not because pre- or post-harvest techniques were irrelevant.
E. A
RTICLES 2.2, 5.1 AND 5.2
1. General
4.54 The United States argued that the Japanese varietal testing requirement was maintained
without sufficient evidence in contravention of Article 2.2. Furthermore, it was not based on an
assessment of risk in contravention of Articles 5.1 and 5.2. The SPS Agreement indicated in
Article 2.2 that a Member was not allowed to maintain a phytosanitary measure "without sufficient

54 See Section VI of this report in respect of the Panel's consultation with scientific experts. The experts advising
the Panel are listed under paragraph 6.4.

scientific evidence" and a measure had to be "based on scientific principles". Article 5.1 stated that a
Member had to ensure that its phytosanitary measure was based on an assessment, "as appropriate to
the circumstances, of the risks to ... plant life or health".
4.55 In relation to risk assessment, the United States recalled that the Appellate Body Report on
EC - Hormones had made it clear that Article 5.1 could "be viewed as a specific application of the
basic obligations contained in Article 2.2 of the SPS Agreement".
55 Thus, the United States argued,
Article 2.2 and Article 5.1 of the SPS Agreement were necessarily linked together. Under Articles 5.1
and 5.2 of the SPS Agreement, Japan was required to base its SPS measure, in this instance variety-
by-variety testing for quarantine efficacy, on a risk assessment. Such an assessment was important in
establishing whether the measure was "based on scientific principles", and was not "maintained
without scientific evidence" (Article 2.2).
4.56 The United States stressed its request that the Panel make findings with respect to both
Article 2.2 and Article 5.1 of the SPS Agreement. In the view of the United States, the heart of the
dispute was the fact that Japan’s measure did not merely lack an assessment of risk, it lacked
sufficient scientific evidence to support the measur e. This had also been stressed by the Appellate
Body's statement in EC - Hormones that "Articles 2.2 and 5.1 should constantly be read together.
Article 2.2 informs Article 5.1: the elements that define the basic obligation set out in Article 2.2
impart meaning to Article 5.1".
56 Furthermore, in that dispute, where the Panel made a finding under
Article 5.1 but not Article 2.2, the Appellate Body expressed that it was "surprised by the fact that the
Panel had not begun its analysis of this whole case by focusing on Article 2 that is captioned ‘Basic
Rights and Obligations,’ an approach that appears logically attractive".
57
4.57 The United States stressed that a failure to make a finding with respect to Article 2.2 could lead
to confusion rather than furthering the objective of "providing security and predictability to the
multilateral trading system".58 If the Panel were to make a finding on all of the elements necessary to
make a determination with respect to Article 2.2 (which in this dispute would be inherent in a finding
with respect to Article 5.1), and yet not actually make that determination, it could be perceived by some
as implying that Japan’s ban was not maintained without sufficient scientific evidence. This negative
implication would be inaccurate. Japan's measure did not merely lack a risk assessment, it was not
supported by scientific evidence. In that regard, the lack of sufficient scientific evidence was a more
fundamental and fatal flaw than the lack of a risk assessment, and thus was a more important finding
than a finding under Article 5.1.
2. Article 2.2
(a) General
4.58 The United States recalled that Article 2.2 of the SPS Agreement required a Member to base
its phytosanitary measures on scientific principles and prohibited a Member from maintaining sanitary
and phytosanitary measures "without sufficient scientific evidence". The SPS Agreement did not
define "based on scientific principles". However, at a minimum, to base a measure on scientific
principles required that a WTO Member had identified a particular risk that the measure was
designed to protect against, and conducted some review of scientific evidence or other relevant
scientific information to demonstrate that the measure in fact protected against that risk. The risk that

55 Op. cit., p.72, paragraph 180.
56 Ibid.
57 Ibid., paragraph 250.
58 Article 3.2 of the DSU.

had to be addressed was whether there was a possibility of the inadvertent entry of codling moth from
US products, on a variety-by-variety basis, in light of pre- and post-harvest practices and quarantine
treatment. In other words, the risk of introduction of codling moth in the absence of the varietal
testing requirement. The United States noted that the strongest wording Japan had been able to
employ was that "it is possible there may be variation in the efficacy of disinfestation even if the same
quarantine treatment is applied to different varieties" [emphasis added]. 59 Yet the Appellate Body
Report on EC - Hormones had noted that a theoretical risk would always remain because "science can
never provide absolute certainty that a given substance will not ever have adverse health effects. We
agree with the Panel that this theoretical uncertainty is not the kind of risk which, under Article 5.1, is
to be assessed".60
4.59 The United States claimed that Japan had never been able to provide an explanation as to why
it was necessary to test each variety of a product. There was no scientific reason why the types of
differences that distinguished one apple, nectarine, walnut or cherry from another would be relevant
to the effectiveness of the quarantine treatment. Empirical evidence supported the fact that with
quarantine treatment for codling moth using the pr eferred treatment of MB and/or a two component
treatment of MB and cold storage, the particular variety of the product did not matter for purposes of
the quarantine treatment needed.61 In other words, the quarantine treatment had always been equally
effective irrespective of variety. The additional and redundant testing required by Japan had never
been proven necessary.
4.60 Japan noted that the main thrust of the US argument appeared to be that there was no
scientific basis for varietal testing. Japan maintained that its position was based on a sufficient
amount of available literature and scientific data which indicated the possible presence of a
statistically significant difference in the efficacy of known disinfestation measures across varieties of
the same products, differences which could require application of a different treatment.
4.61 Japan claimed that the import prohibition fully met the criteria, developed by the Appellate
Body in EC - Hormones, of being "based on" scientific evidence, or a risk assessment:
"... Article 5.1, when contextually read as it should be, in conjunction with and as
informed by Article 2.2 of the SPS Agreement, requires that the results of the risk
assessment must sufficiently warrant – that is to say, reasonably support – the SPS
measure."
62
4.62 Japan had relied on the following available evidence which had led to the conclusion that the
import prohibition was warranted against codling moth:
(a) Honma, K. (1976) Plant Protection 30: 237-244. (in Japanese)
(b) Proverbs, M.D. et al., (1982) Can. Entomol. 114: 363-376.
(c) Moffitt, H.R. et al., (1988) J. Econ. Entomol. 81: 1511-1515.
(d) Beers, E.H. et al., (1988) In Orchard Pest Management, pp. 63-68.
(e) MAFF (1995) In Handbook of Agricultural Statistics, pp. 225-238. (in Japanese)
(f) IIE (1995) Distribution Maps of Pests, Series A. No. 9, CAB International.

59 Japan's response to Question 4 of US Consultation Questions (US Exhibit 3).
60 Op. cit., paragraph 186 (italics in original).
61 US Exhibit 2.
62 Op. cit., paragraph 193.

(g) Tokyo Astronomical Observatory (1995) In Chronological Scientific Tables, pp.198-
199. (in Japanese)
(h) Yamaguchi, A. & A. Otake eds. (1986) In Disease and Invertebrate Pests of Fruits
Trees, pp. 226-230. (in Japanese)
(i) Japan Tariff Association (1993, 1994, 1995) In Japan Exports & Imports No. 12,
p. 94. (1993), p. 93. (1994), p. 93. (1995).
4.63 These pieces of literature contained or lead to the following findings:
(a) Codling moth could survive in areas where the effective cumulative temperature (the
yearly sum of the daily temperature figures which are 10 degrees or above) was 600
day-degrees and the lowest monthly temperature of the coldest month fell below 10
degrees centigrade. Most Japanese regions met this criteria.
(b) The insect was able to establish itself in Japan in light of the amount of host plants.
(c) When codling moth larvae diapaused through the winter in cocoons, and, after the
pupal stage in early spring, the moth emerged during the blooming season of apples.
(d) In contrast to a sedentary pest such as scale, codling moth was able to spread by
flight. There was a report that the moth could move within a range of 300 to 500 feet,
and records that they had flown 1,000 to 2,000 feet. Moreover, a Canadian study on
control by sterile insect releases found that male moths released from a point were
recaptured in traps 3.5 kilometres to 7.2 kilometres away.
(e) The larvae entered into the apple fruits at every growing stage, and it severely
damaged commercial value.
(f) In an area not subject to pest control, the infestation rate in pears was 57.3 per cent to
100 per cent.
(g) Newly hatched larvae entered into the fruits from the calyx end or from cracks, and
were very difficult to detect.
(h) Export markets could be lost.
(i) Control costs could increase.
4.64 From the above findings, Japan drew the following conclusions and decided that import
prohibition was the appropriate phytosanitary measure:
(a) codling moth had a high potential (grade a) of entry and establishment, while its
spread potential was medium (grade b);
(b) the pest was highly likely to cause grave damage (grade a) to agricultural production
once it was introduced into the country; and,
(c) there was no practical, effective inspection method to detect the presence of the moth
inside fruits, and the level of management difficulty was the highest (A1).
4.65 The United States claimed that Japan was mischaracterizing the dispute. The issue was not
whether codling moth was of quarantine significance. That was not in dispute. What was in dispute
was whether there was any scientific basis for Japan’s assumption that variety affected efficacy of
treatment against codling moth. Japan had asserted that variety presented a risk in relation to quarantine
treatments with methyl bromide, and yet it could not support this theoretical uncertainty with scientific
evidence. In fact, Japan had instituted this requirement before any of the scientific studies on which it

claimed to rely had been conducted. 63 Japan had yet to explain why varieties needed to be tested
separately. If each variety needed to be tested separately because varietal differences "could" matter,
then why not separately test by a whole series of other arbitrary factors, such as by color, by ripeness,
or by length of time in shipment? In essence, Japan had assumed variety mattered, and then
challenged exporting countries to prove it did not. According to the United States, this was not the
way the SPS Agreement was structured.
4.66 The United States noted that addressing the risk at issue came down to an exporting
Member’s ability to kill the pest in question, codling moth, in each variety of a product. This was the
fundamental question that had to be analyzed under Articles 2.2 and 5.1 of the SPS Agreement. Japan
had established a particular level of mortality that it wanted any quarantine treatment to achieve. This
was, however, not the same as an appropriate level of protection. There was no dispute over that
mortality level. The United States wished to clar ify the mortality level did not relate to: sorptive
patterns, CxT findings, preliminary dose-mortality testing or the other information and procedures
that scientists used to identify a treatment that would kill codling moth on a given product. The
significance of those data and techniques was in the contributions that they made to scientists’
conclusions about the fumigant dosage needed to achieve the required level of pest mortality.
4.67 Japan had suggested that the existence of risks could be inferred from the studies it had
submitted. Yet none of the these studies were structured in such a way that they answered the basic
questions of fact which might serve as scientific evidence for the risk at issue. Even if Japan had been
accurate with respect to the significance of every piece of data it had cited, and the conclusions of
each and every study, the question would remain whether Japan’s varietal testing requirement was
supported by sufficient scientific evidence, and whether the risk at issue was more than hypothetical.
The United States maintained that responses by the experts advising the Panel had been very helpful
in clarifying that it was not possible to attribute the data variations cited in these studies to varietal
differences, let alone to differences of a magnitude that could affect treatment efficacy. The United
States stressed that all of the experts had confirmed that the existence of varietal differences affecting
treatment efficacy could not be determined on the basis of the evidence before the Panel.
4.68 Japan claimed that the risk it faced was not the "theoretical uncertainty" the Appellate Body
had referred to in EC - Hormones. The present case was substantially different from EC – Hormones;
while the safety of the substances was internationally established in the EC – Hormones case, no one
doubted the risk posed by codling moth to Japan. While the European Communities only asserted that
safety of hormones was not proven beyond doubt, Japan's concern was based on available data. This
data was the basis for Japan's scientific concern over the efficacy of the treatment across varieties.
4.69 Hence, Japan disagreed with the US argument that Japan referred only to theoretical
uncertainty as the basis for "varietal testing" for MB fumigation, and, therefore, that Japanese policy
was not based on a risk assessment. First, Japan recalled that there was no requirement of "complete
testing and review of each variety" under the Japanese policy (paragraph 4.23). All that was required
of each variety was the demonstration of efficacy in small-scale laboratory experiments to compare
dose-response with other varieties (at the time of initial lifting), or with the approved treatment level
(at the time of additional lifting). Large-scale demonstration was only required of a representative
variety. Second, Japan noted that there was nothing inherently wrong about Japan's concern in respect
of varietal differences. Japan claimed that the United States had itself established different treatment
standards for different varieties of mangoes (paragraph 4.136 and following paragraphs).
4.70 Japan noted that in the case of MB fumigation to counter codling moth, data was available in
the form of varietal dose-response results which suggested the possible presence of differences in

63 The United States noted that the earliest reference wherein Japan identified any basis for its assumption that
variety affects efficacy of quarantine treatment was in the Wearing et al.,1980 Study on New Zealand Cherries (contained in
Japan, Exhibit 13).

efficacy of fumigation treatment between varieties. Japan's hypothesis was that characteristics of a
particular variety could affect fumigation efficacy, possibly by their impact on the CxT value
(explained in further detail in paragraph 4.109 and after). In light of available data and present
knowledge of the fumigation process, this was a reasonable argument. Japan's policy was thus based
on a scientific hypothesis which was in turn supported by empirical data, in full conformity with the
obligations contained in Article 2.2 and Article 5.1.
4.71 Japan noted that the United States apparently found rationale for the product-by-product
testing in the fact that the efficacy of the treatment applied for one variety of a product had never
varied from that of the treatment applied to another variety of the same product. The United States
repeatedly emphasized the fact that an MB fumigation standard had not been modified in the past.
Japan acknowledged that it was true that existing tr eatment levels of host plants of codling moth had
been found effective for additional varieties. However, as a matter of science, all this proved was the
efficacy of the treatment on the tested varieties; it fell short of showing absence of varietal difference
within a product altogether. Possibly, the US ar gument could be founded on an intuitive judgement,
based on past experience. However, out of 100 varieties of nectarines in commercial production, only
three varieties had been tested by a large-scale (10,000 to 30,000 insects) test. Similarly, out of 44
varieties of apples, only two had been tested by the large-scale test.
4.72 Japan further noted that, according to the US argument, if there were 100 varieties in one
product category, a treatment based on a selective test of any variety would have to be presumed to be
effective for the other 99 varieties. Far more scientific evidence than provided by the United States in
the current proceedings was needed before Japan could reach such a conclusion. The implications of
the US arguments were: (i) that the present quarantine treatment would be effective for unapproved
varieties (including varieties yet to be developed) of apples, cherries, nectarines and walnuts; and, (ii)
for other products which the United States claimed to be within the terms of reference, they would
seek to apply a single treatment for all varieties (including varieties yet to be developed).
4.73 The United States had not provided any information on disinfestation of unapproved varieties
or unapproved products. Obviously, there was no information on products yet to be developed,
possibly through rapidly advancing biotechnology. Nor had the United States presented a theoretical
argument regarding the absence of varietal difference in the disinfestation effects of these products.
Japan had to conclude that the United States had not performed the required demonstration of efficacy
of treatment across varieties.
4.74 The United States stated that it found unremarkable Japan's conclusion that the United States
had not proven, with scientific certainty, the absence of varietal differences. This conclusion did not
more than state, as the Appellate Body Report in EC – Hormones recognized, that science could
never, with absolute certainty, prove the negative. This did not excuse Japan from its obligations to
base its requirement on a risk assessment and sufficient evidence, obligations which Japan had failed
to fulfill.
(b) Probit 9, dose-mortality tests and confirmatory tests
4.75 The United States noted that dose-mortality tests were a critical tool to determine what
commercial treatment might be effective. The dose-mortality test result established a range of
treatments for varieties from which scientists could compare and estimate a final treatment for the
product as a whole. The highest minimum dose observed in the dose-mortality tests that scientists
believe would achieve the level of protection required by Japan (probit 9) was supplemented by 10-20
per cent in the second stage of testing, the confirmatory tests, to account for all sources of variation in
the dose-mortality tests. Thus it was the confirmatory test that was the relevant indicator of efficacy
of treatment.
4.76 The primary reason for the 10-20 per cent (buffer) increase of dose in confirmatory tests, as
well as the reason why scientists did not rely on dose-response results to establish a commercial

quarantine treatment, was that not every replicate of a dose-mortality test would exactly mirror
another. Such factors as experimental error, physical condition of the fruit, sorption of the fumigant
by packing material, and load of fruit in the chamber could account for differences in results.
Phytotoxic
64 effects and effects on residue levels would ordinarily establish the upper bound for a
proposed buffer.
4.77 The United States noted that dose-response data could vary from test to test with the same
species of insect in the same variety. It was well established that insect susceptibility to insecticidal
treatment differed greatly among individual insects, and that the response of insect populations varied.
Since each test necessarily required new insects, the response of test insects would differ naturally
among tests and that accounted in part for the observed variability in dose-mortality test results. 65
With small scale dose-mortality tests, using limited numbers of pests, it was unlikely that variability
of insects relative to susceptibility to the fumigant would be fully represented. Confirmatory tests,
however, contained sufficient numbers of insects (10,000 to 30,000) to ensure representation of
insects at all levels of MB susceptibility.
4.78 Thus, because of natural variation of the test insect population, as well as other factors that
ensured that no one dose-mortality test would be exactly the same as another, it was impossible to
conclude that differences in variety were the explanation for variations in dose-response results. The
United States argued that Japan's own acceptance of varieties that exhibited differences in dose-
response results established that Japan recognized effective quarantine treatment always
accommodated some differences in dose-mortality testing.
4.79 Confirmatory tests established the efficacy of treatment for a product because they took into
consideration all of the sources of variation that could be attributed to the smaller scale tests - most
notably the variation in a pest population, and the experimental error that was bound to occur from
one small-scale test to the next. A confirmatory test would show if a treatment were too low because
there would be an unacceptable rate of survival of the pest. However, confirmatory tests would not
indicate if a treatment were too high.
4.80 The United States noted that although confir matory tests were necessary in the initial
development of a quarantine treatment, they we re unnecessary for every new variety of the same
product. The confirmatory test administered to the initial variety, with a target pest population of 30,000
insects, was of such a design and order of magnitude to include a "real world" range of the pest
population (and therefore relative levels of tolerance to methyl bromide) to detect an inadequate
treatment; in other words, such a large-scale test would capture the range of susceptibility of insect
population. The United States noted that 30,000 codling moths was a substantially larger number of
insects than had ever been encountered in either dose-mortality tests or the actual conditions of US
products proposed as candidates for export to Japan.
66 The United States noted that the experts advising
the Panel had affirmed that the incidence of codling moth on commercially marketable US products was

64 Toxic or injurious to plants.
65 Finney, D.J., (1964) "Statistical Methods in Biological Assay," Griffin, London, pp. 91-92, Cited in Robertson,
Preisler, Hickle and Gelernter, "Natural Variation: A Complicating Factor in Bioassays with Chemical and Microbial
Pesticides", 88(1) J. Econ. Entomol. 1-10, 4-6. (1995). Finney states, "In general the assumption that a response curve once
determined can be used in future assays is inadmissible. Because of natural variation, responses of a gr oup of insects tested
at any one time will therefore never be exactly the same as responses of another group tested at either the same time or at a
different time, regardless of the extent to which bioassay techniques are standardized". In examining responses of Colorado
potato beetle, diamondback moth, and western spruce budworm to three chemical and one microbial pesticides, Robertson et
al., concluded that , "Studies of resistance, control of product quality, and tests of treatment efficacy are complicated by
variation in response to a pesticide (whether chemical or micr obial) that occurs within generations of a particular strain or
within cohorts of a population: such variation is a natural phenomenon when any bioassay is repeated". (US Exhibit 11)
66 The United States referred, in general, to US Exhibits 7, 8, 9, 10, 16 and 30 as well as US Exhibit 22: Work
Plans already in place for the export to Japan of certain varieties of US products.

low. Pest population levels for US products were measured, at most, in extremely low numbers, not
hundreds per fruit, as encountered in the confirmatory test. Any treatment that could kill 30,000 codling
moths in one application would not have difficulty killing the rare individual codling moth that might
appear in a particular commercial shipment. Dr. Heather had further emphasized the robustness of
methyl bromide treatment. The United States further claimed that no literature or scientific data
supported an inherent variability in the products to indicate that a successful confirmatory test on 30,000
insects would not be uniformly successful for all varieties of the host product. The buffer of treatment
used by scientists accounted for the natural variability of the pest and the experimental variability seen
in small scale dose-mortality tests. Due to these factors, a confirmatory test would account for the
variability in small scale tests and establish a treatment that was appropriate for all varieties of a product.
4.81 Japan claimed that empirical dose-response results confirmed the proposition that varietal
differences could affect the mortality effect of MB fumigation. Data which indicated the presence of
such statistically significant differences was contained in:
(a) a 1987 study on American nectarines, in which Summer Grand was found
significantly more susceptible to MB fumigation
67,
TABLE 4
Susceptibility of Codling Moth Eggs to MB Fumigation
(2 hours, 21 oC) in 6 Nectarine Varieties (American Nectarines)
Variety No. of Sample Insects LD50(95%CL)
(g/m3)
Summer Grand 2,210 6.3 (2.2 - 9.1)
May Grand 2,458 14.2 (11.1 - 17.0)
Firebrite 1,880 18.8 (14.7 - 22.8)
Spring Red 1,019 17.7 (14.0 - 20.9)
Fantasia 1,548 17.6 (14.0 - 20.0)
Red Diamond 1,445 18.4 (17.1 - 19.8)

67 Yokoyama, Miller and Hartsell, "Methyl Bromide Fumigation for Quarantine Control of Codling Moth
(Lepidoptera: Tortricidae) on Nectarines,"80 J. Econ. Entomol. 840-842, 1987. (US Exhibit 14)

(b) a 1987/88 test on New Zealand cherries in which LD 50 showed a significantly lower
value for Bing than for Rainer and Sam68, and
TABLE 5
Susceptibility of 1-day-old Codling Moth Eggs to MB Fumigation
(2 hours, 12oC) in 5 Cherry Varieties (New Zealand Cherries)
Variety LD 50 (95%FL)
(g/m3)
LD99 (95%FL)
(g/m3)
Dawson 33.6 (31.8 - 35.1) 61.1 (55.9 - 69.8)
Bing 30.0 (28.9 - 30.9) 46.8 (44.7 - 49.6)
Rainier 33.8 (32.1 - 35.3) 62.2 (57.2 - 70.3)
Sam 35.4 (33.8 - 36.6) 52.9 (49.6 - 58.6)
Lambert 32.3 (29.9 - 34.0) 52.9 (48.4 - 61.7)
(c) a 1983/84 study on disinfestation of New Zealand nectarines in which Fantasia
showed a significantly lower LD50 than Redgold.69
TABLE 6
Susceptibility of 1-day-old Codling Moth Larvae to MB Fumigation
(2 hours at 12oC) (New Zealand Nectarines)
Variety LD 50 (95%FL) (g/m3)L D 99 (95%FL) (g/m3)
Fantasia 10.96 (10.56 – 11.33) 21.15 (19.82 - 22.93)
Redgold 12.09 (11.54 – 12.59) 32.86 (29.83 - 37.12)
4.82 Japan reaffirmed that it used the results of the dose-mortality test (which was part of the
"basic test" paragraph 2.23) in the screening process to select a representative variety.70
4.83 Probit analysis71 typically estimated LD 50 by measurement of the mortality rate in different
doses and regression analysis of the statistically processed data (e.g., probit-conversion). The use of
LD50 value was justified on the basis of relative accuracy of estimation; the confidence level
diminished as the value departed from the 50 per cent. A leading textbook of the analysis stated:

68 Waddell, Birtlex, Dentener and Wearing, "Disinfestation of New Zealand Cherries Cultivar Comparison Test
1987/88", New Zealand. Department of Scientific and Industrial Research, Entomology Division, 1988. (Japan, Exhibit 17)
69 Batchelor, Wearing, O'Donnel, "Disinfestation of New Zealand Nectarines 1983/1984", 1984. (Japan, Exhibit
18)
70 Japan claimed that the estimation of LD 50 by probit analysis was commonly used for evaluation of toxicity of
agricultural chemicals or for comparison of tolerance of pests to disinfestation treatment. Japan referred to e.g., OECD
Guidelines for Testing of Chemicals, adopted 17 July 1992 (Japan, Exhibit 19) for the use of LD 50 value to assess toxicity of
industrial chemicals; Knowles, C. (1988) J. Econ. Entomol.81;1586-1591 for comparison of LD 50 values between different
insect groups. (Japan, Exhibit 20).
71 Definition in paragraph 2.14.

"As will become apparent in later chapters, by experiment with a fixed total number of
subjects effective doses in the neighbourhood of ED 50 [effective dose 50%] can
usually be estimated more precisely than those for more extreme percentage levels,
and this is characteristic of the stimulus; its chief disadvantage is that, especially in
toxicological work, much greater interest may attach to doses producing nearly 100%
responses than to those producing only 50%, in spite of the difficulty of estimating the
former."72
4.84 The use of the LD 50 value (estimated on the basis of the dose-mortality test results) in
comparing efficacy of insecticide agents was a generally accepted scientific method of analysis.
While the United States claimed that the dose-mortality test was effective only for estimating the
ultimate quarantine treatment, it was typically ut ilized for the comparison of susceptibility of
developmental stages of the treatment, in developing treatment schedules.73
4.85 Japan noted that the United States had pointed to "experimental error, physical condition of
the fruit, sorption of the fumigant by packing material, and load of fruit in the chamber", as well as
"natural variation of the test insect population", and claimed that "[t]he condition of any particular
fruit could affect dose-response results". The conclusion drawn was that small scale dose-mortality
tests were unable to correct for these variations. Of these other exogenous variables, "experimental
error, physical condition of the fruit, sorption of the fumigant by packing material, and load of fruit in
the chamber" were the factors which scientists who conducted these tests were responsible for
controlling and consciously made equal.
74 Indeed Japan noted that scientists endeavoured to set
conditions that resembled each other as closely as possible and test insects were taken from artificially
reared groups. For example, Yokoyama and ot her authors of the 1987 experiment on nectarines
described in detail conditions of the fumigation chamber, wrapping of fruits, the load factor, time of
fumigation, conditions of the codling moth and their rearing, and, from these descriptions, one could
recognize that the scientists exerted efforts to ensu re as much similarity between test samples. What
would not be acceptable - if these factors affected the results - was the data they generated, and not
Japan's hypothesis. In Japan's view, any responsible scientist would have to ensure that such
exogenous factors did not falsify the results. It was not scientifically correct to reject a statistical
conclusion on the grounds of experimental errors. If there were such exogenous factors as the United
States claimed, their presence would mean that it was dangerous to draw any kind of conclusion from
the results of such an experiment. None of the experts advising the Panel had concluded that
experimental errors explained all of observed differences in the LD
50 values across varieties.
4.86 Japan claimed that another possible explanation for these factors was that they resulted from
inevitable sampling error. If this was the case, the US position that confirmatory tests were the
relevant indicator would be justifiable. However, Japan noted again that finding ways to alleviate, if
not eliminate, problems of this kind belonged to the scientists of the government of exporting
countries. Japan claimed that while there were always variables other than varietal differences, this
was a statement of truth for any natural phenomenon. It was the responsibility of the exporting
government to identify the variables and establish a treatment which would satisfactorily incorporate
them so that Japan's level of protection would be achieved despite natural variation. The reason Japan
chose to address the issue of varietal difference was because one could reasonably assume the
presence of a route by which fruit characteristics of a particular variety might affect the outcome of a
disinfestation treatment through their impact on CxT values. On the other hand, it was an established

72 Probit Analysis (3rd ed.) Finney, D.J. (1971).
73 Japan referred to a letter of 9 May 1997 from Robert G. Spade, Assistant Deputy Administrator, PPQ, which
stated that: "During the development of quarantine treatment sche dules, does-response data is used only to identify the least
susceptible life stage of a target insect and to estimate effective treatment dosages". (Japan, Exhibit 34).
74 Japan noted that statistical analysis, significance testin g in particular, was precisely the tool to correct for
experiment error.

practice to ignore crop-to-crop or other natural variations in fruits or insects. The issue was the level
of protection which an importing Member had the authority to choose.
4.87 In respect of the issue of the "buffer", Japan noted that while the United States claimed that
the buffer was likely to cover conceivable varietal differences, the experts advising the Panel had not
made any definitive arguments in this regard, nor had the United States explained the scientific
grounds for their conviction. The United States seemed to rely intuitively on the past record of the
efficacy of the treatment for additional varieties. However, as Dr. Heather had pointed out, this was a
question of "risk management". In other words, the risk of inefficacy existed, and the rest was to be
determined by the policy of the importing country.
4.88 Further, in regard to the buffer dose, Japan could not share the view of Dr. Heather and
Mr. Taylor who had stated that the 10-20 per cent additional buffer dose might possibly cover the
presupposed varietal differences. Japan argued that the buffer dose proposed by the United States had
been established on the basis of laboratory scale dose-mortality tests. However, conditions for large-
scale commercial application were different and the effect of gas sorption far from negligible. The
amount of gas equivalent to the buffer dose would be sorbed to warehouses and containers. This
coupled with inevitable gas leakage could mean the CxT values might be lowered to risky levels.
Japan maintained that according to US data, as much as 20 per cent of the methyl bromide dose could
be sorbed by picking bins, warehouses and possible leakage. On that basis, Japan could hardly
assume that the 10-20 per cent buffer dose would cover possible differences of the magnitude of
varietal variations.
(i) Nectarines
4.89 According to the United States , in the consultations Japan had suggested that a scientific
basis for requiring testing for each variety arose from USDA data for the development of an MB
quarantine treatment for codling moth in nectarines for export to Japan. The research alluded to by
Japan was presented in two articles by American scientists, one in 1987 and the second in 1990. In
the first study (1987), dose-mortality tests were conducted on six early- to mid-season varieties of
nectarines: May Grand, Fire Brite, Red Diamond, Sp ring Red, Summer Grand and Fantasia. The test
results had shown that the level of methyl bromide estimated to produce 50 per cent mortality in
codling moth on Summer Grand was significantly lower than for the remaining five varieties.
75 I n
1990, three additional varieties of nectarines were tested (May Diamond, Mayfire and May Glo). The
dose-response of these suggested that a lower amount of methyl bromide was necessary to achieve
100 per cent mortality. 76 Nevertheless, the higher dose established in 1987 was used for the
confirmatory tests. The United States argued that the principal reason a higher dose had been
established in 1987, was because the Summer Grand variety that had "stuck out" in dose-mortality
tests in 1987, had also required the highest minimum dose
 to achieve 100 per cent mortality.
4.90 In the 1990 study on nectarines, the authors had looked at different insect and fruit
interactions to evaluate the necessity for varietal testing. Dose-response data had been obtained for
eggs fumigated on different fruit substrates (i.e., different species: nectarines, plums, peaches, apples)
as well as eggs on waxed paper inserted into the fumigation chamber with a load of fruit. The authors
compared LD50 and LD 95 for codling moth eggs. The scientists found that while there might have
been slight apparent numerical differences in codling moth susceptibility to methyl bromide (dose-
response) on various substrates, this did not affect the efficacy of the quarantine treatment, nor had
these differences been anything but natural variations in the response of the test insects. The highest
minimum doses tested that caused 100 per cent mortality of codling moth on nectarines, peaches,

75 Op. cit., pp. 840-842. (US Exhibit 14)
76 Yokoyama, Miller and Hartsell, "Evaluation of a Me thyl Bromide Quarantine Treatment to Codling Moth
(Lepidoptera: Tortricidae) on Nectarine Cultivars Proposed for Export to Japan," 83 J. Econ. Entomol. 466-471, 1990. (US
Exhibit 12)

plums and apples, and waxed paper during dose-mortality tests were well below the 48 g/m 3 methyl
bromide that was used in the ultimate quarantine treatment for nectarines established through
confirmatory tests. Based on these results, the authors of the study had concluded that testing for
efficacy of methyl bromide against codling moth eggs on every nectarine cultivar proposed for export
to Japan was unnecessary to show the efficacy of the quarantine treatment.
77
4.91 The United States claimed that, in consultations, Japan had pointed to the relative
susceptibility to methyl bromide of codling moth eggs on Summer Grand and noted differences in the
physical characteristics of the fruit as an indicator of significant differences among varieties of the
same agricultural product which warranted varietal testing. Yet the United States was of the view that
the authors' comment regarding flaws in Summer Gr and did not state or imply that these flaws were
characteristic of the variety. Because varieties ripen at different times, scientists had only a small
window of opportunity to test the quarantine trea tment simultaneously on several varieties. Thus
idiosyncratic aspects of the physical condition of the specific fruit due to harvest practices, weather
conditions, the amount of time one variety may have been stored while waiting for other varieties to
be harvested for testing, and other external factors were reflected in the dose-mortality tests. The
condition of any particular fruit could affect dose-response results.
4.92 Moreover, although Summer Grand required less methyl bromide than the other varieties to
achieve 50 per cent mortality of the test insects, it required more methyl bromide to achieve 100 per
cent mortality of the test insects than the other five varieties tested. This apparently contradictory
information indicated that the natural variation of the insect, and factors such as experimental error,
fruit condition, and factors that could affect the amount of fumigant to which insects are exposed,
such as sorption by the packing material and load in the chamber, all played a role in differing dose-
response results.
78
4.93 It was also significant to note that over the summer of 1997, Vail and Yokoyama had re-tested
two varieties of nectarines - May Grand and Summer Grand. In the dose-mortality tests, the level of
methyl bromide required to achieve a lethal dose for 50 per cent and 95 per cent of codling moth eggs
did not differ significantly. 79 This was in contrast to the initial 1987 nectarine study results. The
United States argued that these 1997 results confirmed that the differences noted in 1987 were due to
natural variation of the insects and other experimental variables. The authors of the 1997 study had
stated the "extremely high numbers of insects killed in large-scale confirmatory tests and the virtual
non-host status of nectarines attest to the high level of security afforded to this treatment to prevent
introduction of codling moth to Japan via nectarine cultivars". In re-testing this variety in 1997,
however, results of dose-mortality testing had indicated that the highest minimum dose for Summer
Grand was now a dose closer to the six varieties tested in 1990. This indicated that a dose closer to
that seen with dose-mortality tests for the 1990 batch might be the more appropriate level of treatment
for nectarines.
4.94 More significantly, the confirmatory test applied in 1987 had established the efficacy of the
treatment on all nectarines tested. A dose that was 20 per cent greater than the highest minimum dose
required for 100 per cent mortality during the dose-mortality testing had been proposed as a
quarantine dose for these six varieties.
80 This treatment had proven successful to achieve Japan's level

77 Ibid., pp. 466, 468, 470. (US Exhibit 12)
78 The United States noted that probit model of analysis looked only at the linear relationship between dose and
mortality (as stated in US Exhibit 28). There were other, more sophisticated statistical models which included consideration
of natural variation of the test insect population. Such a model had been used to re-analyze all varieties in the 1987 and 1990
studies by Yokoyama et al., Taking natural variation into consideration, it had been shown that the LD 50s among varieties
were not significantly different (in Robertson and Yokoyama, "Effect of Nectarine Cultivar on Response of Codling Moth
(Lepidoptera: Tortricidae) to Methyl Bromide Fumigation," Unpublished, 1998. (US Exhibit 15)).
79 Vail and Yokoyama, "Nectarines: The Issue of Varietal Testing", unpublished. (US Exhibit 16)
80 MB fumigation at 48 g/m3 for 2 hours at 21º C or above and 50 per cent or less load.

of protection and had been accepted by Japan for all six varieties. As it was the large-scale
confirmatory tests at a lower dose had not been done in 1990, because the 1987 results indicated that a
higher dose was necessary. Thus confirmatory tests at 48 g/m
3 were completed (which was the dose
established in 1987 that was derived from the highest minimum dose believed to achieve Japan's level
of protection in the dose-mortality tests with 10-20 per cent added) and showed that this dose was
effective for all nectarine varieties. Hence, the Un ited States reaffirmed that confirmatory tests were
the only relevant indicator of efficacy of a quaran tine treatment. The United States maintained that
Japan's claim that variations in dose-mortality tests obtained from two groups of varieties tested three
years apart were the result of inherent varietal differences was scientifically invalid. Such a position
ignored natural variation in responses of insects, and lack of a common control among tests (i.e., no
one variety was tested in both years). Dose-mortality testing would inevitably show natural variability
among dose-response results. This did not justify re-establishment of confirmed quarantine treatments
for codling moth on a given product.
4.95 The United States noted that similar findings on different host fruit species and other insect
species had been published in Japan; Misumi had investigated quarantine control through MB
fumigation of the Japanese mealybug and the citrus mealybug naturally infesting Satsuma
mandarins.81 All stages of the two species of pests were reared on fresh pumpkins as an alternative to
Satsuma mandarins because of difficulty in rearing mealybugs on the Satsuma mandarin. The
physical and chemical differences between Satsuma mandarins and pumpkin were considerable. Yet
despite the use of different host plants, the authors concluded this was of no significance to the
efficacy of the fumigation process. Hence, Japanese scientists were willing to accept efficacy of
quarantine treatment for a pest as it related to two radically different products, pumpkins and
mandarins. This experiment supported the position of the United States that requiring exhaustive data
on individual varieties of a product was not necessary. The study demonstrated that methyl bromide,
when applied at specified concentrations over specified periods of time, killed codling moth in the
same way, regardless of variety, and even regardless of substrate.
4.96 Japan recalled that at the time of the additional lifting of the ban for the 1990 varieties, even
though a dose of 20 g/m
3 had been proven effective to ensure 100 per cent mortality, the United States
had chosen to propose 48 g/m 3 as the treatment level. 82 The United States did have the option to
propose 20 g/m 3 or 24 g/m 3, adding a "buffer", as the treatment for the additional three varieties.
Japan accepted the application of the existing treatment 83 as the on-site confirmatory test had
demonstrated its efficacy. This did, however, raise a practical question as to what level of treatment
the United States would have proposed had the six varieties (tested in 1987) not been approved
initially. It was reasonable to assume that they would not have proposed 48 g/m 3, but would have
chosen a level around 24 g/m3 instead. The United States could not argue that "confirmatory tests …
showed that this dose (of 48 g/m 3) was effective for all nectarine varieties" (paragraph 4.94). At the
most, the United States could argue that this dose was effective for the six varieties tested in 1987,
and might be effective for the same varieties in the future. 84 A similar problem arose with respect to
New Zealand cherries of the Bing variety (from paragraph 4.103).

81 Misumi, Kawakami, Mizobuchi and Tao. No. 30 Res. Bull. PL. Prot. Japan 30: 57-68, 1994. (US Exhibit 13, in
Japanese)
82 Japan noted that the scientists had determined the treatment level of 48 g/m 3 by multiplying the complete
mortality dose of 40 g/m3 by 1.2 times (buffer).
83 Paragraph 4.94.
84 Japan noted that Robertson ( Op. cit., US Exhibit 15) re-analyzed the data on American nectarines (1987 and
1990) by a statistical method developed by the author and concluded that no statistical difference was observed. However,
the analysis failed to reject even a 190-times difference of confidence level. Such a wide degree of ambiguity was not
acceptable to Japan.

TABLE 7
Doses which Achieved 100 per cent Mortality of One-day-old Eggs
Year Varieties Dose (g/m 3)
1987 Summer Grand 40
May Grand 35
Firebrite 35
Spring Red 35
Fantasia 30
Red Diamond 30
1990 May Diamond 15.0
Mayfire 17.5
May Glo 20.0
4.97 Japan acknowledged that the issues of natural va riation within the same insect group or year-
to-year variation of the fruits were scientifically genuine. There would always be variables other
than varietal differences. The existence of various exogenous variables did not by itself prove that
observed differences were not attributable to varieties. The task of a scientific demonstration began,
not ended, with the discovery of variables. Therefore, Japan had no reason to doubt the 1997 data on
two cultivars of nectarines (May Grand and Summer Grand) which indicated, contrary to the 1987 test
data, absence of a statistically significant difference between LD values. Explanatory variables other
than varietal differences could include natural variation in insects or crops. However, Japan pointed
out, once it was assumed that populations were different year-to-year, or case-by-case, any increase in
the sample number was pointless, and large-scale confirmatory tests could not predict efficacy of a
treatment either, because the confidence in the test s would end at the termination of that particular
crop year (for the particular crop population), or with the last individual of that particular group of
codling moth (for the particular insect population). This also belied the US claim that "the
confirmatory test applied in 1987 established the efficacy of the treatment of all nectarines tested"
(paragraph 4.94) The United States should have argued that the test did not confirm efficacy of the
treatment for any variety in any year except 1987. Al ternatively, the United States meant to say that
there were unknown exogenous variables which significantly affected the results of these studies.
However, from a practical point of view, this argument was equally empty; efficacy of a treatment
could never be established.
4.98 Japan noted, in respect of the US reference to the 1987 nectarine study (paragraph 4.89), that
the authors had stated that "no differences in egg susceptibility to MB were found among five infested
cultivars". Hence, the conclusion had applied only with respect to the five varieties out of total of six
varieties tested. In fact, a difference in efficacy had been found between the last variety (Summer
Grand) and the others tested. The authors acknowledged that "[a] comparison of the LD
50's showed
that eggs on Summer Grand were significantly (non-overlap of 95 per cent CL) more susceptible to
MB fumigation than eggs on other cultivars".85
4.99 In respect of the US reference to the 1990 nectarine study (paragraph 4.90), Japan noted that
the authors had stated, "[w]e propose that a c x t product of 68.0±3.0 gh/m 3 methyl bromide ... would
be a useful measurement to help maintain treatm ent security for control of codling moth on all

85 Supra note 67, p.841. (US Exhibit 14)

nectarine cultivars".86 The proposed measurement of the CxT product was the basis for the cited
conclusion. However, the present treatment of nectarines did not control the CxT value during the
fumigation process. Consequently, its efficacy across all cultivars could not be assumed from the
authors’ statement.
4.100 In respect of the US reference to the Vail et al., 1997 re-test of Summer Grand and May
Grand nectarines (paragraph 4.93), Japan pointed out that the authors had not demonstrated that a
"high level of security" was equivalent of Japan's level of protection. Furthermore, the authors had
not denied contribution of varietal differences; they had stated "the source of variation cannot be
attributed solely to cultivar differences". (emphasis added).
4.101 The United States refuted Japan’s claim that the order in which dose-mortality tests were
conducted could result in the establishment of a treatment for one variety that would fail on additional
varieties. As it had not been shown that variations in dose-mortality test data reflected underlying
varietal differences affecting treatment efficacy, there was no evidence to support this assertion. The
1997 retest of the 1987 Summer Grand nectarine data indicated that the 1987 test results were
anomalous. Had the results been in reverse order, there would have been no reason to believe that a
treatment based on the lower dosage levels would not have been effective. And had the anomalous
1987 data been too low rather than too high, this would not have resulted in an ineffective quarantine
treatment since the confirmatory test on the same variety would have failed. The United States
stressed that an ineffective treatment would not be established in the first place, let alone be permitted
to remain in place for future varieties. In addition, the United States noted that a confirmatory test
could never indicate whether a dose was too high, only if was too low.
4.102 Japan noted, in this respect, that the results which the United States now described as
"anomalous" were the United States' own test results which had formed the basis for lifting the ban on
the importation of the products at issue.
(ii) Cherries
4.103 Japan recalled the conclusion of the authors of a 1987/1988 New Zealand study on cherries:
"For the range of mortalities that we considered, the relationship between the c x t sum
and the injected dose is close to linear, with a non zero constant term that varies
between cultivars and between season. Thus, the injected dose that is required to
achieve a given mortality will vary between cultivars. Factors that may affect the
sorption pattern of any one cultivar require further investigation."
87
4.104 In the case of New Zealand cherries, Japan noted that the same treatment level had been
initially established for the Dawson and Bing varieties. When Rainier, Sam and Lambert varieties
were additionally approved, test results showed a significantly higher level of efficacy for the Bing
variety in comparison to Dawson, Rainier and Sam in terms of non-overlap of 95 per cent confidence
intervals of LD
50 and LD99. As it was, since the treatment level had been set at a level which would
ensure effective treatment of Dawson, the less susceptible variety, its efficacy was confirmed for the
additional three varieties as well. Similar to the case of nectarines, the data implied a possibility,
however, that, had Bing alone been approved initially, the treatment could have been established at a
level which would have been found ineffective for Dawson, Rainier or Sam (Table 5, above).

86 Supra note 76, p.470. (US Exhibit 12)
87 Maindonald, Waddell and Birtles, "Response to Methyl Bromide Fumigation of Codling Moth (Lipidoptera:
Tortricidae) Eggs on Cherries", New Zealand. J. Econ. Entomol. 85(4): 1220-1230, 1992. (Japan, Exhibit 21 and
US Exhibit 4)

4.105 Hence, Japan argued there were cases where, while the actual treatment levels were not
modified, variations did exist to such a degree that different treatment levels could have been
proposed depending on the sequence in which the varieties were tested. By no means did this imply
that varietal difference did not exist because the same treatment of the pest had been found effective
for all approved varieties of the respective products.
4.106 The United States pointed out that the authors of the New Zealand study on cherries had
concluded that "although the results indicated a higher injected dose when 'Rainier' had been
fumigated compared to 'Bing', the large change between seasons in the results for 'Sam' indicated that
seasonal differences (perhaps associated with differences in maturity) may have been more important
than cultivar".
88 Many factors could have contributed to a variation in Bing in 1987. The authors had
noted that "sources of variation that may affect results include the insect material, cherry sorption, and
measurement and circulation of methyl bromide within the chambers". 89 For example, Sam cherries
had different sorption patterns between 1987 and 1989. Again, the Japanese overlooked the existence
of natural variation of the test insects, whether it occurred in the United States or another exporting
nation.
4.107 Most significantly, the United States claimed that Japan had also ignored the stated
conclusion of the authors that the developed quarantine treatment for cherries was applicable to all
cherry varieties. "Where complete kill is the objective, the commercial rate used by cherry exporters
is 64 g/m
3, 12º C, 2 hours, and 40% load. This treatment controls codling moth eggs potentially
infesting any of the cultivars considered". 90 [emphasis added]. For all season-cultivar combinations,
in both years, the highest lethal dose levels of methyl bromide at the LD 95 had still been at least 10
g/m3 below the "complete kill" commercial dose used to do the confirmatory test. As the authors
further noted in the article abstract: "The commercia l treatment thus affords a high level of security".
Japan had incorrectly interpreted the significance of these studies and erroneously concluded that the
efficacy of treatment could vary within a product.
4.108 The United States argued that there was always a degree of variability in any dose-mortality
test from variety to variety and even within the same fruit variety. Such variations were the inevitable
result of differences in natural conditions and testing environments, from crop to crop and year to
year. Japan had already accepted a certain dose-response variability in allowing imports of the
varieties that it had already approved. This normal variability in testing results could not constitute a
legitimate basis for denying approval for other varieties of the same products. Japan maintained that
the existence of various exogenous variables did not in itself prove that the observed differences were
not attributable to varieties.
(c) CxT Values
4.109 Japan claimed that in the specific case of MB fumigation, the link between varietal
differences and divergent efficacy of the fumigation treatment could manifest itself by way of the
difference in the CxT value.
91 The process could take the following sequence: When MB gas was
injected into the fumigation chamber, it would be absorbed by the surface or the pulp of the fruits. If
the sorption varied depending on the variety of the fruits, the amount of fumigant remaining in the
chamber air would vary in an inverse relationshi p to the sorption. Then the CxT value, a known

88 Ibid., p.1227. (Japan, Exhibit 21 and US Exhibit 4)
89 Ibid., p.1224. (Japan, Exhibit 21 and US Exhibit 4)
90 Ibid., p.1229. (Japan, Exhibit 21 and US Exhibit 4)
91 Japan noted that in fact, the mode of action of MB treatment on insects was not fully known, and there could be
other mechanisms by which varietal differences could affect the efficacy and referred to by Bell et al. , (Price and
Chakrabarti, "The Methyl Bromide Issue", 1996. (Japan, Exhibit 11))

indicator to control the degree of efficacy of the treatment 92, would vary as well depending on the
variety of the fruit. Japan claimed that it could reasonably be assumed, by ways of the CxT values,
that there was a route by which the characteristics of a fruit of particular variety could affect the
outcome of disinfestation efficacy.
4.110 Japan claimed that there were three empirical cases which demonstrated a statistically
significant difference in the CxT value between te sted variety samples, including the case of three
cultivars of walnuts the United States referred to in their submission
93:

92 Japan noted that E. J. Bond had stated that "[t]he use of integrated c x t products is particularly useful in routine
fumigations when the reaction of a particular species or groups of species has been carefully worked out under the range of
conditions likely to be encountered. It has been used su ccessfully in large-scale eradication campaign" (Bond, E.J., "Manual
of Fumigation for Insect Control", 1984. (Japan, Exhibit 12)).
93 Japan noted that in addition, in a test on New Zealand cherries, it had been found that "[g]as chromatograph
readings during the fumigations suggested that ‘Bing’ cherries absorbed less methyl bromide than 'Dawson' cherries",
Wearing, Batcholor, Maindonald, "Disinfestation of New Zealand Cherries", Department of Scientific and Industrial
Research, 1981. (Japan, Exhibit 13).

(a) 1985 tests on three varieties (Hartley, Payne and Franquett) of American walnuts
(1985 Walnut Test Report): CxT values ha d been significantly different between
Franquett (75.7 gh/m3 at the first replicate; 71.5 gh/ m 3 at the second replicate) and
Payne (109.4 gh/m3, and 99.9 gh/m3, respectively). 94
TABLE 8
Fumigant Concentration and CxT Values for 3 Varieties of
American Walnuts
Variety Replicates Fumig ant Concentration (g/m3)C x T V a l u e
(gh/m3)
Immediately after
Injection of
Fumigant
4 hours after
Injection
Hartley 1
2
54.0
54.1
16.2
15.0
101.0
87.4
Payne 1
2
51.2
50.8
18.9
17.5
109.4
99.9
Franquett 1
2
51.3
33.7
12.7
12.9
75.7
71.5
(b) 1988 tests on three varieties (May Glo, Mayfire and May Diamond) of American
nectarines: CxT values of May Diamond had showed a statistically significant
difference with the other two cultivars for most of the doses. 95
TABLE 9
CxT Values of American Nectarine Varieties and Doses
(2 hours, 21oC, 50% Load Factor)
Variety CxT Values (gh/m 3±SD) for Fumigant Doses
48 g/m3 64 g/m3 96 g/m3 128 g/m3
May Glo 64.8±0.8 86.6±1.8 132.7±5.1 173.8±7.3
Mayfire 63.8±1.2 86.4±3.4 135.0±4.9 182.4±10.2
May Diamond 72.4±4.4 98.2±8.4 158.2±7.5 208.2±9.7

94 Vail, Hartsell and Tebbets, "Walnut On-Site Operational (Demonstration) Test Report to Japanese Ministry of
Agriculture, Forestry and Fisheries", USDA/ARS, 1985. (Japan, Exhibit 14)
95 Vail, "Efficacy of Methyl Bromide for Codling Moth on Nectarines – Consideration of Nectarines as a Product
Group", USDA, 1988. (Japan, Exhibit 15)

(c) 1997 tests on three varieties (Fantasia, Flavortop and Shuhou) of Japanese nectarines:
There had been a statistically significant difference in CxT values between Shuhou
and Fantasia.
 96
TABLE 10
Residual Gas Rate of Fumigant, CxT Value and Fumigant Sorption of Fantasia, Shuhou and Flavortop
Nectarine Varieties in MB Fumigation
(48g/m3, 20oC, 2 hours, 0.143t/m3 Load Factor)
Variety Replicates Weight
(kg)
No. of
Fruits
(Unit)
Residual
Gas Rate
(%)
CxT values Sorption
(mg/kg)
gh/m3 Mean ±
SD
Fantasia 1
2
3
4.218
4.213
4.218
32
32
32
68.2
67.1
68.4
71.1
69.9
72.0
71.0
 ±1.1
133.1
139.8
134.2
Shuhou 1
2
4.217
4.212
30
30
69.7
70.3
66.1
65.9
66.0
±0.2
146.7
144.9
Flavortop 1
2
4.213
4.216
26
26
69.7
68.4
69.8
67.8
68.8
±1.4
136.2
141.9
4.111 Japan noted that these significant differences were attributable to varieties as the CxT value
was affected by physical and chemical properties of the fruits, which were attributable to varietal
characteristics. For example, in the case of walnuts, Japan suspected that the differences in the oil
content of the walnuts, a qualitative feature of the particular variety, affected the sorption of fumigant
and the resulting CxT values. Similarly, the CxT value variation in the 1997 nectarine experiment
(third table under paragraph 4.110) was considered attributable to Shuhou’s rougher surface, another
feature characteristic of the variety, compared to other varieties.
4.112 Japan noted that despite test-to-test variation, statistical analysis using Tukey's multiple range
test had found a statistically significant difference in the CxT values between Payne and Franquett
varieties of walnuts. Statistically speaking, Franquette's CxT value was lower than that of Payne at the
confidence level of 95 per cent. Similarly, the same statistical tool had found a significant difference
among the nectarine varieties in the second and third experiments set out in paragraph 4.110 above.
4.113 Japan claimed that the study on Satsuma mandarins and pumpkins which the United States
had cited (paragraph 4.95) was in fact fully consistent with the present Japanese practice. Japan
recalled that the hypothesis underlying the Japanese policy was that varietal differences could be such
as would affect sorption of fumigant by the fruits, resulting in different CxT values and hence efficacy
of MB fumigation treatment. In the cited experiment, faced with the difficulty of rearing and placing
mealybugs on Satsuma mandarins
97, scientists had chosen to use pumpkins as a proxy for Satsuma

96 Research Division, Yokoyama Plant Protection Station, "Methyl Bromide Sorption in Nectarine Varieties",
unpublished, 1997. (Japan, Exhibit 16)
97 Japan noted that it was difficult to rear mealybugs on Satsuma mandarins because, under conditions suitable to
the insects, the fruits easily decayed and/or the peel hardened. If one tried to place mealybugs on Satsuma mandarins after
rearing them on other fruits, on the other hand, their natural mortality would be very high because of possible damage the
insects would suffer upon such placement.

mandarins because the CxT values between the two plants were remarkably close. It was incorrect to
state that "Japanese scientists were willing to accept efficacy of quarantine treatment for a pest as it
related to two radically different products". Quite the contrary, these products were almost identical
as far as the crucial factor – the CxT value – was concerned. This experiment by no means
undermined the hypothesis relating to the varietal differences.
TABLE 11
CxT Values for Satsuma Mandarins and Pumpkins98
Subject Replicates Load (kg) CxT Value
(mgh/l)
Satsuma
Mandarins
1
2
3
1.45
1.50
4.10
92
92
98
Pumpkins 1
2
3
1.45
1.50
4.10
94
93
95
4.114 The United States claimed that minor differences in CxT values between varieties did not
indicate differences in varieties of a single product. While CxT values could assist in developing a
commercial treatment to kill codling moth, they did not in and of themselves indicate differences in
varieties. The difference in CxT could be just as pronounced within the same variety. The experts
advising the Panel had not accepted the notion that th ese differences could be attributed to varietal
differences and had furthermore pointed out that, whatever the cause of CxT variation between varieties,
these differences had not been observed to affect treatment efficacy.
4.115 Reasons for CxT value variations included (i) minor differences in leakiness of fumigation
chambers; (ii) the amount of toxicant taken up by the pr oduct or the packaging material; (iii) the
amount of product being fumigated (the load); (iv) the accuracy of the various measurements used to
calculate the CxT; and, (v) the times at which the concentrations in the chambers were sampled. The
United States stressed that CxT values were used by researchers only as a control mechanism for
fumigation trials. They were not useful for concluding that there were differences in varieties. In
addition, the United States pointed out that the experts advising the Panel had confirmed that test-to-
test variation was inevitable in small-scale tests because of natural variations in pest populations,
testing equipment and conditions, and product samples. Also, variations within a product were
likewise inevitable from season to season, tree to tree a nd fruit-to-fruit within a variety. The experts
had, according to the United States, in this regard noted that fruit-to-fruit variation could greatly
exceed variety-to-variety variation, if any. Variation could also occur because of the difficulty of
having different varieties in the same physiological state because of ripening times.
4.116 Importantly, the United States stressed that the experts advising the Panel had made very clear
that it was not possible to conclude that that test -to-test variation in CxT values were attributable to
varietal differences rather than any of the other sources of variation described.
4.117 In the 1992 New Zealand study on cherries, the CxT values for the Sam variety of cherry
varied from one season to the next (paragraph 4.106). Moreover, from the Summer Grand and May
Grand varieties of nectarines tested in the Vail et al., 1997 nectarine re-test (paragraph 4.93), it was
possible to see that CxT values differed within the same varieties compared to the 1987 nectarine
study results. In large-scale US tests of nectarines, it was again evident that there could be as much

98 Supra note 81, pp.57-68. (US Exhibit 13).

difference in CxT values within a single variety as among varieties. The difference in CxT value ranges
within May Grand nectarines, in 1991, was comparable to the difference between May Grand and Royal
Giant nectarines in 1989 and 1991 99 (Table 12 below). The United States noted that in respect of
walnuts, the Hartley variety referred to by Japan exhibited a difference in CxT values from one test to
the next; this difference was greater than the difference in CxT values between the varieties Hartley
and Payne.100 Hence, in the view of the United States, these results illustrated that there could be any
number of reasons why CxT values varied and their variations were not indicative of any varietal
characteristics.
TABLE 12
CxT Values From Large-scale Tests on
U.S. Nectarine Varieties in Carton Containers
1989 1991 1992
Royal Giant 69.6
72.1
67.8
May Grand 70.8
79.4
Fantasia 73
4.118 In respect of walnuts, the United States noted that Japan had pointed to the results of the 1985
Walnut Research Report101 to assert that a difference in CxT values in dose-mortality tests applied to
varieties of fruits supported the need for varietal testing. Again, the United States claimed that test-to-
test variation of one variety had been as great as that found among all three tested varieties of
walnuts.102 CxT values were an indication of how much toxicant was available to the target insect.
Regardless of the observed differences in the CxT values, there was no difference in the efficacy of
the quarantine treatment for the three varieties of walnuts. Japan approved the methods and data
generated during these studies and had not requested different quarantine schedules for the three
varieties.
103 In this respect, the United States noted that in bilateral talks in March 1997, the parties
had discussed the Japanese decision not to allow import of the walnut variety Eureka due to perceived
differences in sorption of methyl bromide. In fact, Japan had refused importation because, although
its de-sorption rate had not been significantly different, Eureka had consistently higher residues, likely
attributable to higher natural oil content (that would retain the methyl bromide), as compared with
other varieties of walnuts.
104 Concerns over methyl bromide residues were exclusively related to food

99 Yokoyama, Miller, and Hartsell, "Methyl bromide efficacy and residues in large-scale quarantine tests to control
Codling moth (Lepidoptera: Tortricidae) on nectarines in field bins and shipping containers for export to Japan". 87 J. Econ.
Entomol. 730-735, 1994. (US Exhibit 36)
100 US Exhibit 31.
101 Vail, Nelson, Hartsell and Tebbetts. "Development of a Quarantine Treatment for the Codling Moth in Walnuts
for Export to Japan. (Not published in a scientific journal). Walnut Research Report 1985. Walnut Marketing Board,
Sacramento, CA., pp.149-154. (US Exhibit 17)
102 Ibid., p.150. (US Exhibit 17)
103 The United States recalled that the uniform treatment for walnuts was 56g/m 3 methyl bromide fumigation for 4
hours at 15.6º C at 100mm HG, and a load factor of less than 50 per cent.
104 Hartsell, Tebbets, and Vail, "Methyl Bromide Residues and Desorption Rates from Unshelled Walnuts
Fumigated with a Quarantine Treatment for Codling Moth (Lepidoptera: Tortricidae)" 84 J. Econ. Entomol. pp. 1294-1297,
1991. (US Exhibit 18)

safety and had nothing to do with the efficacy of the quarantine treatment. The United States insisted
that perceived differences in de-sorption rates (rate at which fumigant leaves a product) did not
indicate varietal differences with respect to quarantine protection. Although Eureka had consistently
higher residues than the other three varieties tested, these differences had not been statistically
significant and had not affected treatment efficacy. In fact, preliminary tests showed that there was no
survival of test larvae in any of the varieties treated. The authors of the 1991 report on the 1985 tests
on walnuts, had stated that "no significant differences were found in mortality of larvae among the
four walnut cultivars tested, nor was variation in the size of walnuts of each cultivar a significant
factor".
 105 At the second substantive meeting of the Panel, the United States submitted an article
which clarified that oil content in walnuts did not vary by variety. 106 Hence, even if sorption was
affected by oil content, there was no basis for concluding that this varied by variety.
4.119 The United States pointed at the Japanese admission that for apples, cherries, nectarines and
walnuts, there was no disagreement as to the efficacy of the treatment as applied to the approved
varieties (paragraph 4.6). The United States claimed that implicit in this acknowledgement was a
recognition that there would be variations in the preliminary dose-mortality testing and these
differences did not alter the final quarantine treatm ent. These variations were evident in the test
results of these approved varieties. Japan’s r ecognition acknowledged that CxT values could vary,
but that they were not relevant in reaching efficacy (in killing the required amount of codling moth).
To suggest that the variations of data in dose-mortality testing on its own represented differences in
varieties was inconsistent with this concession on the part of Japan.
4.120 Moreover, the United States claimed that CxT was not an indicator of likeness among
varieties or products. In reference to Satsuma mandarins and pumpkins Japan had asserted that it was
within reason to accept treatment for a pest on tw o different products so long as the two products had
identical CxT values (paragraph 4.113). This ignored all other physical aspects of the product such as
size, as well as what biological stage of the pest would interact with a product. The United States
recalled that the CxT value measured the amount of fumigant outside of a pr oduct in a fumigant
chamber. Yet codling moth was not only on the outs ide of nectarines. The pest actually burrowed
into apples, cherries and walnuts. CxT was silent on the way the fumigant interacted with the pest
inside the product. If CxT were the standard of efficacy, then treatments would be developed that
were ineffective in addressing the stage of pest, where the pest was located on the product, and the
obvious differences among products that necessitate different treatments. Irrespective of what
accounted for differences in CxT values, it had to be remembered that these values were merely tools
in estimating and establishing a treatment level that resulted in mortality. Treatment efficacy did not
rely on CxT values. It relied on the ability to kill the required level of pests.
4.121 Finally, the United States claimed that Japan had, in attempting to justify its theory,
mischaracterized the meaning of the article by E.J. Bond that it cited (footnote 92 to paragraph 4.109).
While Japan seemed to be suggesting that Bond linked CxT values to variety of the product and
differences among those varieties, he was in fact discussing CxT values as they related to the pest, and
specifically the role of CxT values as a tool to observe the interaction of the fumigant and the pest. The
Bond article did not suggest that differences in CxT indicated differences in variety.
107
4.122 In addition, the United States noted that Japan had stated that the method it used to test the
statistical significance of walnut data was "Tukey's multiple range test". However, tests such as Tukey's

105 Hartsell, Vail, Tebbets and Nelson. "Methyl Bromid e Quarantine Treatment for Codling Moth (Lepidoptera:
Tortricidae) in Unshelled Walnuts", 84 J. Econ. Entomol. pp. 1289-1293, 1991. (US Exhibit 19)
106 Greve, McGranahan, Hasey, Soder, Kelly, Glodhammer and Labavitch, "Variation in Polyunsaturated Fatty
Acids Composition of Persian Walnut", Department of Pomology , University of California, USA , J. Amer. Soc. Hort. Sci
117(3):518-522, 1992. (US Exbibit 40)
107 Bond 1994, p.25. (Japan, Exhibit 12)

were based on an analysis of variance. In order to be used correctly, several assumptions had to be met,
among them the requirement that samples used in replicates had to be randomly and independently
selected and the requirement that the variances of the different samples were homogeneous. Tukey's test
was not relevant to an analysis of the walnut data Japan examined
108 because this data failed to meet
both assumptions. For each of the varieties listed in Table 8 (page 41), the walnuts used in each
"replicate" were taken from the same batch of wa lnuts. The samples were thus not independently
selected, and it was inaccurate to describe the test on each variety as "replicates". Second, the variances
of the data for each variety were not homogeneous. 109 Finally, the United States pointed to the
observation of the experts advising the panel that even if Japan had demonstrated "statistically
significant" differences in CxT, such differences would not necessarily have been a reflection of
significant biological differences which could affect efficacy.
4.123 In sum, CxT values did not indicate differences among varieties. Those differences were just as
pronounced within varieties. The United States claimed that Japan implicitly had to have understood
this conclusion since it did not require different quara ntine treatments or testing for the same variety
despite differences in CxT values within varieties.
4.124 Japan contended that among the exogenous factors to which the United States attributed the
differences in varieties (as set out in paragraph 4.115), the load factor had been controlled in the
second and third of the three empirical cases described in paragraph 4.110 above. Other factors, such
as leakiness of fumigation chambers or the measurement error, called for further empirical
confirmation. They by no means vindicated the US position that varietal differences were irrelevant
to the statistically significant differences in CxT values. In addition, the factor of "the amount of
toxicant taken up by the product", which the United States admitted affected the variation in CxT
values, was exactly what Japan believed was a key determinant of the values which could be
attributable to varietal differences. Japan contended that even though codling moth larvae burrowed
into the pulp from the exterior of the fruit, it respired the surrounding, fumigated air. It was therefore
reasonable to assume that that CxT was indicative of some interaction with the fumigant.
4.125 In respect of the US argument in paragraph 4.117, regarding the 1992 New Zealand study on
cherries, Japan noted that the cited results indicated possible interaction of variables, and by no means
proved the absence of a link between a significant difference of CxT values and varietal differences.
Japan reiterated that it was the scientists' responsib ility to identify variables, account for them and
devise ways to alleviate statistical problems, unless one were to discard the CxT value in
phytosanitary experiments.
110 After all the efforts to discredit the statistical significance of variation
of the CxT values, the United States had nevertheless admitted that they had value as "tools in
estimating and establishing a treatment level that results in mortality" (paragraph 4.120). If the values
could vary for "any number of reasons", and if scientists were incapable of controlling these reasons,
Japan failed to understand how the values could "estimate" or "establish" any parameter.
4.126 Furthermore, in respect of the same study, Japan noted that the authors' conclusion applied
only to the five varieties tested for efficacy confirmation: "[b]ecause the five cultivars of cherry that
we considered have different sorption patterns, different injected doses are required to achieve a given
level of mortality. ... Where complete kill is the objective, the commercial rate used by cherry
exporters is 64 g/m
3, 12 C, 2 hours, and 40 per cent load. This treatment controls codling moth eggs
potentially infesting any of the cultivars considered". 111 Japan stressed that the authors had, in fact,

108 In paragraph 81 of Japan's first submission.
109 US Exhibit 39.
110 In this respect, Japan noted that it was puzzled by the small number of samples in the 1997 retest (30
individuals compared to 160 in 1987).
111 Op. cit., p.1229. (Japan, Exhibit 21 and US Exhibit 4)

acknowledged the presence of varietal difference; for they had stated: "We found differences in
sorption of methyl bromide between cultivars and between seasons" 112 and, "For the range of
mortalities that we considered, the relationship between the c x t sum and the injected dose is close to
linear, with a non zero constant term that varies between cultivars and between season. Factors that
may affect the sorption pattern of any one cultivar require further investigation." 113 Japan reiterated
that with regard to nectarines, the same authors had suggested that the CxT value "would be a useful
measurement to help maintain treatment security for control of codling moth on all nectarine
cultivars".114
4.127 With regard to walnuts, the reason why Japan did not request different quarantine schedules
for the three varieties was because, under the concept of a representative variety discussed before,
Japan had accepted the large-scale efficacy data on Hartley and found that the proposed treatment
would disinfest codling moth to the satisfactory level. It was not because varietal differences were
irrelevant.
4.128 Japan noted, in respect of the US citation of the Hartsell et al., 1991 walnut study on MB
treatment (paragraph 4.118), that the study did not include comparative tests of varieties and the cited
conclusion was drawn from the result of 100 per cent mortality which was achieved for all varieties
stored in the same fumigation chamber at the same time. Absence of varietal differences could not be
proved under such conditions. In fact, in a preliminary study it was stated the "[t]here were no
significant differences due to cultivar except Eureka, which had higher residue at all three
temperatures tested and is indicative of the higher oil content found in this cultivar", and that "[a]ll
cultivars desorb MB at about the same rate with the exception of Eureka which due to its higher oil
content has a slightly longer retention time".
115 Japan had concluded from these results that the
Eureka variety tended to retain MB at a higher level due to its oil content and could show differences
in efficacy, and that further comparative tests would be needed on the variety. In the end, the United
States had dropped the Eureka variety from the request for approval, and import prohibition was lifted
for the other three varieties in 1986. Japan stressed that the issue of MB residue in Eureka was not
related to concern over food safety.
4.129 With regard to Bond's study (paragraph 4.121), Japan had cited an authoritative view on the
utility of the CxT value as an indicator of efficacy of fumigation. The Japanese argument was simply
that if CxT value varied depending on the variety, efficacy of a treatment might vary according to
varieties.
4.130 The United States maintained that Japan had misinterpreted the scientific data. Japan was
alleging that the primary basis for its assumption (t hat variety mattered) was that differences in CxT
values meant that there were differences in sorption between varieties that affected efficacy of treatment.
The fact that CxT values had been observed to be different in tests involving different varieties appeared
to be the sole basis of Japan's theory that variety mattered. Yet the experts advising the Panel had stated
that there was no evidence to support Japan's suggestion that sorption differences had been shown to be
large enough to affect treatment efficacy. Such differences, would, in their expert opinion, have to be
"significant" or "large" in order to create sorption differences of sufficient magnitude to affect treatment
efficacy. Furthermore, Dr. Ducom had emphasized that there was a lack of precise studies on factors
contributing to differences in sorption levels and that the "notion of CxT has not been studied
enough". In respect of sorption and apples, the United States pointed out that Dr. Heather had
explained that while sorption might have an impact on MB treatment, it would have no impact on cold

112 Ibid., Abstract, p.1222. (Japan, Exhibit 21 and US Exhibit 4)
113 Ibid., Discussion, p.1228. (Japan, Exhibit 21 and US Exhibit 4)
114 Supra note 76, p.470. (US Exhibit 12)
115 Supra note 101, p.107. (US Exhibit 17)

treatment. Thus, there were no grounds to even speculate that sorption differences among apples
could affect treatment efficacy.
4.131 Moreover, the United States noted that, according to Dr. Ducom, if Japan were serious about
developing sufficient scientific evidence to support its theory that CxT variations might be related to
varietal differences affecting treatment efficacy, Japan could conduct specific studies on the matter.
Yet no effort had been undertaken in this respect. In fact, Japan had not put its own theory into
practice. In regard to those products that Japan indicated exhibited differences in CxT values (nectarines
and walnuts), the fact remained that Japan had never attempted to confirm its hypothesis, to explore why
CxT values varied, or to link differences in CxT values with differences in products. In regard to other
products subject to this measure (apples, apricots, cherries, pears, peaches, plums and quince) Japan had
not made any such observations or assertions regarding variations in CxT. Therefore, presumably there
was no basis for applying its measure a priori to these products.
4.132 The United States reiterated that the measure of efficacy was not CxT values, but whether the
exporting country could eliminate the pest of concern at a sufficient rate to achieve Japan’s level of
phytosanitary protection. Differences in CxT values were the result of "real world" variables typically
seen in testing procedures and did not indicate th at varietal differences affected the efficacy of
quarantine treatment. Under the SPS Agreement, Japan was required to have a scientific basis for its
assumption that variety did matter, but its embrace of CxT values as the basis of such a theory fell short
of that responsibility.
4.133 The United States claimed that if Japan truly believed that CxT values were the indicator of
efficacy, there would be no need to show that the dose of fumigant resulted in a particular level of
mortality of the pest. Yet the ability of the United States to gain access for a variety of fruit into Japan
depended upon its ability to show that the requisite amount of codling moth had been killed. CxT values
could vary from Payne walnuts to Franquette walnuts, but the MB treatment was the same because that
treatment killed codling moth uniformly in both vari eties. There could be differences in CxT values
between May Glo and May Diamond n ectarines, but the MB treatment was identical for these two
varieties because that treatment killed the codling moth uniformly. It was evident that CxT was not a
direct indicator of efficacy of treatment. The indicator of efficacy of quarantine treatment was the
ability to uniformly achieve the required level of mortality of codling moth. In every instance,
regardless of CxT values, and regardless of variety, the level of phytosanitary protection required by
Japan had been achieved with a treatment that was uniform for all varieties of a product.
4.134 The United States also noted that the arbitrary manner in which the measure was applied further
called into question its scientific basis. As Japan had explained it, if an exporting country had ten
varieties of a commodity available for export, a so-called representative variety could be used in a
confirmatory test. Yet if those same ten varieties were proposed in sets of five over two different years,
a confirmatory test that previously would have sufficed for all ten varieties had now to be applied twice.
There was no logic to this application. Moreover, the United States noted that Dr. Heather had pointed
out that if one were to accept that dose-response tests could be used to establish varietal differences, why
then would it be necessary to follow-up these tests on newly tested varieties with a confirmatory test?
4.135 Japan noted that it had never claimed that varietal differences always resulted in differences
in CxT values. What was argued was that there existed studies which detected a statistically
significant difference of CxT values between vari eties. Furthermore, replication-to-replication
variation was in itself irrelevant; testing in rep licates was exactly for the purpose of eliminating
experimental bias. Presence of replication-to-replication variation by no means impaired the utility of
the CxT value as an indicator of varietal differen ce. Japan pointed out that Dr. Ducom had endorsed
the presence of the link between varietal differences and differences in the CxT value. In any event, it
was the United States' responsibility to identify relevant variables which they claimed existed and
establish a treatment which would satisfactorily incorporate them so that Japan's level of protection
would be achieved despite such variations.

(d) Comparison with other products
4.136 Japan noted that while the main focus of the dispute at issue related to fumigation, there were
cases where certain differences in efficacy of thermal treatment between different varieties were
observed. Japan recalled that the United States had established standards which treated mango
varieties differently for hot water treatments. 116 The immersion time was set differently according to
varieties with physical differences (the size and shape) of the mango. The treatment time was shorter
for fruits with a flat and long shape, or for smaller fruits.
4.137 Japan did not doubt that the United States had a genuine reason to differentiate the varieties as
they related to physical characteristics of the fruits, in light of their impact on the efficacy of the
treatment. Under the same logic, Japan's policy of differentiating varieties was justifiable as they
related to physical/chemical characteristics of the fruits, which might impact on efficacy of treatment.
Moreover, in 1993, when additional varieties of Thai mangoes (Nam Dokmai, Rad and Pimsen
Daeng) were investigated, Japan had found by a mortality comparison that the existing vapor heat
treatment (46.5 ° Celsius for 10 minutes, developed for the Nang Klamguan variety) was not
sufficient. This resulted in a new vapour heat treatment (the temperature to be raised by a fixed rate
to 43 degrees Celsius and held at over 47 degrees for 20 minutes).117
4.138 Japan noted that other countries also considered varietal differences in their design of
quarantine treatment. According to a Japanese survey, in addition to the Republic of Korea, both
Canada and Australia considered relevant issues surrounding varietal differences. Japan noted that
Australia had indicated in a communication to Ja pan that when new varieties were proposed for
approval into Australia, their "likely procedure w ould involve re-evaluation of the relevant pest risk
analysis (PRA)," and that "[t]he PRA process woul d consider any relevant technical information on
varietal differences". Hence, contrary to the United States' assertion, Australia would perceive the
risk of varietal differences and act accordingly.118 In the case of New Zealand, the authorities’ manual
for development of fruit fly disinfestation treatment stated:
"A disinfestation treatment may need to be developed for each variety of fruit
separately. While a variety may be described formally in the procurement of
proprietary rights, where a variety is not formally described or where varieties can be
shown to be morphologically and physiologically similar, definition of the distinctive
fruit types must be provided (for example, ovoid eggplant as opposed to oblong
eggplant, or long green chilli as opposed to small yellow chilli)."
119
4.139 The United States noted that Japan, in referring to thermal treatments as used on mangoes
from Thailand, was attempting to infer that the US practice of treatment for mangoes made distinctions
based on variety; this was distorting the scope of the dispute by introducing alternative treatments
which were not within its scope. It was clear to the United States that the scope of the dispute related to
products that could be host to codling moth and for which the quarantine treatment of methyl bromide or
methyl bromide and cold storage was used.
4.140 Nevertheless, the United States was compelled to rebut the assertion made by Japan that the
United States differentiated quarantine treatment for pests on a variety-by-variety basis. US scientists
were aware that such objective morphological charac teristics as fruit size and shape, irrespective of
variety, were important parameters in determining the schedule for heat treatments. The treatment

116 PPQ Treatment Manual. (Japan, Exhibit 22)
117 Unahawutti, U. et al., Unpublished, 1991. (Japan, Exhibit 23)
118 Japan, Exhibit 38.
119 MAF, Regulatory Authority Standard., paragraph 3.2.1. (Japan, Exhibit 24)

schedule for mangoes in the United States was not by variety but by size and shape, which could vary
within the same variety. As Dr. Heather had noted, size and shape of the fruit "are a varietal
characteristic but not exclusively so". The larger or rounder the fruit, the longer it took to heat the
fruit to the centre. Thus the heating rate for fruit th at was small or flat was much faster than for fruit
that was large or round. This was evident from the heat treatment schedules for mangoes found in the
APHIS Plant Protection and Quarantine Treatment Manual.
120 Moreover, the United States did not
require testing of new mango varieties, but assigned a treatment based on the size and shape of the
proposed import variety. Furthermore, the United States noted that the experts advising the Panel had
stated that reactions of different products to differe nt treatments "have nothing to do with each other"
and that fumigation bore little relationship to other treatments.
121 It was therefore not relevant to
compare thermal treatment on mangoes with fumigation on the products at issue.
4.141 The United States also noted that Japan had indicated that Canada, Australia and New
Zealand all took into account varietal differences in quarantine treatments. Recent communications
with these countries clearly refuted this assertion:
(a) Australia had indicated in a communication with the United States, that it did not
require assessments by variety for fumigation quarantine treatments. 122 In respect of
the letter from Australia referred to in paragraph 4.138 above 123, the United States
emphasized that Australia did not require varietal testing nor did Australia apply
different quarantine treatments based on variety. The letter in fact indicated that
Australia had not prejudged the need for a varietal testing requirement, that it would
examine "any relevant scientific or technical information on varietal differences" in
deciding whether to extend existing treatm ents to additional varieties. The United
States maintained that the experts had confirmed that there was no scientific evidence
that varietal differences affected efficacy.
(b) The Government of New Zealand had similarly confirmed that it did not differentiate
between varieties of a product
124; moreover, the "MAF Regulatory Authority
Standard 155.02.03 Specification for the Determination of Fruit Fly Disinfestation
Treatment Efficacy" addressed the possibility of a statement of varieties for
dimethoate dip treatments for fruit fly in tomatoes. 125 All other fruit fly treatments
were determined on a species basis.
(c) The Government of Canada, in a communication dated 17 April 1998, had confirmed
that it did not require testing by variety for quarantine treatments.126
Hence, in sum, none of these countries required varietal testing for quarantine treatments.
4.142 In respect of Australia ((a) above), Japan restated that contrary to the United States' assertion,
Australia also considered varietal differences in their design of quarantine treatment and would act
accordingly (paragraph 4.138). Japan refuted the US statement that the treatment schedule for

120 United States Department of Agriculture, Animal and Plant Inspection Service, Treatment Manual, V.2, pp.
5.45 - 5.58. (US Exhibit 32)
121 See Section VI of this report, Question 15.
122 Letter to Ms. Audrae Erickson from Mr. Paul Morris, dated 20 April 1998. (US Exhibit 33)
123 Letter to Mr. Takeo Kocha from Mr. Christopher W. Wood, dated 18 June 1998. (Japan, Exhibit 38)
124 Letter to Ms. Audrae Erickson from Mr. Tony Pautua, dated 9 April 1998. (US Exhibit 34)
125 Dated 22 November 1994. (Japan, Exhibit 24)
126 Letter to Ms. Audrae Erickson from Dr. J.E. Hollebone, dated 17 April 1998. (US Exhibit 35)

mangoes was not by variety. Clearly the US schedule referred to varieties. If, as the United States
implied, a "flat, elongated" variety such as Frances was sometimes treated as a "rounded" variety, an
almost insurmountable administrative problem would arise. It appeared impractical to implement the
schedule without a predetermination of the treatment on a varietal basis. Although this schedule was
for hot water treatment and not MB fumigation, it did show that concern over varietal difference was
quite common.
3. Article 5.1
4.143 The United States recalled that Article 5.1 of the SPS Agreement required WTO Members to
"ensure that their sanitary or phytosanitary measures were based on an assessment, as appropriate to
the circumstances, of the risks to human, animal or plant life or health, taking into account risk
assessment techniques developed by the relevant international organizations".
4.144 The United States noted that in bilateral consultations, Japan had asserted that it had
conducted a risk assessment according to the proced ures set out in the FAO PRA Guidelines (these
procedures are described in paragraphs 2.29 and below).
127 The document provided to the United
States subsequent to the consultations, however, did not support this assertion. In the view of the
United States, Japan had not followed the FAO guidelines. 128 The document which Japan described
as a "risk assessment" merely asserted that codling moth was a pest of quarantine significance. 129
This was not in dispute. What was in dispute was whether the measure taken by Japan to ensure its
level of protection was based on scientific principles, maintained with sufficient scientific evidence,
and based on an assessment of risk. On this point, the Japanese document was silent. In other words,
Japan's consideration of factors such as the ability of the pest to survive in Japan's climate, the biology
of the moth as it related to crop seasons in Japan, the ability of the pest, once it had entered Japan, to
infest and harm crops, or, the costs of such harm - were only relevant to the determination that codling
moth was a quarantine pest. It was the practice of lifting the import ban only upon a showing that the
same quarantine treatment was effective for every variety of a product that was the phytosanitary
measure at issue. The United States had seen no assessment of that measure.
4.145 Japan argued that it had conducted a full-scale risk assessment in 1996 to ensure that current
plant quarantine measures, and import prohibition in particular, were scientifically justified. This risk
assessment was fully consistent with the PRA Guidelines established by the FAO. In this process,
Japan had evaluated the "likelihood or entry, establishment or spread of a pest … within the territory
… according to the … phytosanitary measures which might be applied, and of the associated potential
biological and economic conseque nces…" (SPS Agreement, Annex A, paragraph 4) Furthermore,
Japan stressed that an individual risk assessment of a particular plant was performed whenever an
exporting government requested the lifting of an import prohibition of the pr oduct, or other
modification of quarantine measures.
4.146 The immediate impetus for the full-scale risk assessment had come in 1995, when the FAO
adopted the PRA Guidelines. In this risk analysis, Japan's objective had been to identify particularly
dangerous pests which might not be countered by the normal screening process and which were likely
to cause serious damage, and to effectively prevent their introduction by means of import prohibition
or otherwise. In order to ensure objectivity of the analysis, Japan had sought advice on the selection
of relevant factors and the pest risk assessment procedure from 28 researchers belonging to various

127 Japan's response to Question 3 of US Consultation Questions. (US Exhibit 3)
128 The United States noted that reference to the FAO Guid elines was not intended to establish a particular risk
assessment framework, nor did it imply that failure to comply with the FAO guidelines nece ssarily constituted a violation of
the SPS Agreement.
129 Japan, Exhibit 9.

national laboratories. Further professional input to the draft procedure was given by an Expert
Committee in June and September 1996. The committee advised on the standards by which
phytosanitary measures were chosen according to the level of the risk. This advice and internal
review resulted in a numerical evaluation standard. The 12 members of the expert committee were
those recommended by the Japanese Society of Applied Entomology
130 and Zoology and the
Phytopathological Society of Japan (six experts in entomology and nematology and six experts in
plant pathology).
4.147 Following the procedure developed with academic input, Japan identified 117 species of
agricultural/forestry pests on the basis of documentary evidence as those which could cause a serious
damage once they were introduced into the Japanese territory, and analyzed the risk of each of them.
Through this process, the 15 quarantine pests, including codling moth, were found not to be
adequately detectable by the normal inspection procedure. Japan therefore decided to maintain an
import prohibition on host plants of these pests. Furthermore, Japan concluded that ten quarantine
pests were detectable by growing-site inspection of the government by the exporting country. 131
While their risk of introduction and damage was comparable to that of the 15 species, as from April
1998, host plants of these pests were allowed to be imported into Japan subject to completion of the
growing-site inspection.
4.148 With regard to codling moth, Japan described the 3-stage process as follows: Stage 1 of the
analysis consisted of the re-evaluation of 117 specific pests, initiated in 1996. In terms of the PRA
Guidelines, the initiation was justified as the result of "[a] policy decision … to revise phytosanitary
regulations or requirements concerning specific pests".132
4.149 In Stage 2 , Japan developed a relative, numerical evaluation standard which graded pests
from "a" (high) to "c" (low), and assessed each factor of the analysis according to the standard.
Valuation was objectively based on Japanese and foreign literature.
4.150 First, the guidelines required an assessment of the pest’s establishment potential in light of
biological suitability of the PRA area and a pest's survival capability. In light of the Japanese
environmental conditions and the abundance of host plants, as well as known characteristics of the
codling moth, Japan's analysis found that codling moth had a grade "a" establishment potential.
4.151 Second, in respect of the spread potential, the Guidelines required an assessment of possible
spread in light of biological factors such as suitability of the natural and/or managed environment for
natural spread of the pest, movement with products or conveyances, or potential natural enemies of
the pest in the PRA. In the present case, codlin g moth showed a relatively low reproductive capacity
and was graded "b" in terms of spread potential.
4.152 Third, the PRA Guidelines required consideration of factors affecting economic consequences
of the pest introduction and spread. In this analysis, type of damage, crop losses, loss of export
markets, increases in control costs, environmental damage, or perceived social costs such as
unemployment were incorporated in the Japanese analysis of pests. Host plants (apples, cherries and
other fruits) of the insect were produced in great quantity in Japan. The potential substantial damages
led Japan to conclude that the insect was graded "a" in terms of economic importance.

130 Entomology: the study of insects.
 131 (i) Sugar beet nematode; (ii) fals e root-knot nematode; (iii) banana bu rrowing nematode; (iv) Fusarium wilt
of pea; (v) bacterial wilt of beans; (vi) watermelon bacter ial fruit blotch; (vii) Stewart’s wilt; (viii) Goss’s bacterial wilt
and blight; (ix) broad bean stain virus and (x) broad bean true mosaic virus.
 132 PRA Guidelines, Item 8, paragraph 1.2 .

4.153 Factors which affected the introduction potential were enumerated in the "partial checklist" in
paragraph 2.3 of the PRA Guidelines. 133 Codling moth was capable of surviving the transportation
stage, hidden inside the fruits which would be imported in large quantities. Factors affecting
establishment (e.g., number and frequency of consignments of the product, intended use of the
product) had to also be considered.134 In respect of these factors, codling moth ranked high, and grade
"a" was given to the insect.
TABLE 13
Overall Risk Grading of Pests Based on the Score of Grades
Score of Grades in Stage 2 Analysis Overall Risk Grading
a for "potential economic importance" and at least two
a's for the other potentials
A (very high risk)
At least one aB (high risk)
No aC (low risk)
All c's D (very low risk)
4.154 In summary, as outlined above in respect of the Stage 2 analysis, codling moth was graded
"b" in terms of spread potential after establishment, but was given grade "a" in the rest of the Stage 2
analysis. Subsequently, Japan performed overall grading of the risk the pest posed and found that the
insect’s overall risk was grade "A" (very high risk). It thus met the requirement of a quarantine pest
under this stage of the analysis, and Japan decided to proceed to Stage 3.
4.155 Under Stage 3 of the PRA Guidelines, pest risk management entailed the task of choosing
appropriate phytosanitary measures against quarantine pests identified through the Stage 2 analysis.
Possible phytosanitary measures were enumerated in paragraph 3.1 of the Guidelines. Notably, the
Japanese inspection process, disinfection/disinfestation or import prohibition defined under the Plant
Protection Law all appeared in the menu of options under the PRA Guidelines (paragraph 2.30).
4.156 The choice of an appropriate phytosanitary measure (or measures) was based on efficacy and
impact of these options, and, for this purpose, paragraph 3.2 of the PRA Guidelines identified 9
factors which were relevant to the efficacy and impact, and required that these be considered in the
policy choice (paragraph 2.32). In order to incorporate these factors in an operational model, Japan
first developed a standard decision tree of five questions to evaluate the degree of difficulty (or ease)
in managing the risk of the pest, with the results expressed in five levels from A1 to C.
4.157 These assigned levels reflecting the degree of difficulty (or ease) in managing the risk of the
pest were then combined with the grades of overall risk (A to D) determined by Stage 2. Resulting
combinations, which appeared in the left two columns of the Table 14 below were linked to specific
risk management measures in the right column, in order to prevent the pest’s introduction into the
Japanese territory.

 133 The factors are: (i) opportunity for contamination of products or conveyances by the pest; (ii) survival of the
pest under the environmental conditions of transport; (iii) ease or difficulty of detecting the pest at entry inspection; (iv )
frequency and quantity of pest movement into the PRA area by natural means, and (v) frequency and number of persons
entering from another country at any given port of entry.
 134 The checklist further enumerated: (i) number of individuals of a given pest associated with the means of
conveyance; (ii) intended use of the product and (iii) environmental conditions and availability of hosts at the destination
and during transport in the PRA area.

4.158 In the case of codling moth, Japan recalled that newly hatched larvae were known to enter
into fruits, and it was virtually impossible to detect these larvae by normal visual means. Growing-
site inspection was equally ineffective because the insect penetrated the products in the post-harvest
stage. Finally, post-entry inspection was impractical because it would destroy the pr oduct's
commercial value. Thus the insect was classified in "LEVEL A1" according to the decision tree.
4.159 Under the PRA (Stage 2) and the study of mana gement options (Stage 3), the overall risk of
the codling moth was evaluated to be A (very high risk), and the level of difficulty of management
was in the highest bracket, A1. Japan found it to be impossible to properly manage the risk of the pest
by means other than import prohibition, and decided to maintain the measure.
TABLE 14
Choice of Appropriate Phytosanitary Measures Based on Overall
Risk Grading and Levels of Management Difficulty
Overall Risk Grading Levels of Management Difficulty Quarantine Measures
AA 1 Import prohibition of host plants
A2 Growing site inspection
B1 Post-entry quarantine inspection
B2 Import inspection by specific
techniques
B B1 Post-entry quarantine inspection
B2 Import inspection by specific
techniques
C Normal import inspection
CB 2 Import inspection by specific
techniques
C Normal import inspection
D- (Non-quarantine pests)
Note: Even though other combinations of risk evaluation and difficulty may exist theoretically, Japan noted that there were no known
examples. Therefore, the above combinations exhausted all practical possibilities.
4.160 The United States restated that the document which Japan asserted was its assessment of risk
under Article 5.1 of the SPS Agreement, merely addr essed whether the codling moth was a pest of
quarantine significance. That was not in disp ute. However, the Appellate Body Report in EC -
Hormones made it clear that Article 5.1, relating to asse ssment of risk, "may be viewed as a specific
application of the basic obligations contained in Article 2.2 of the SPS Agreement". Japan had been
unable to provide a risk assessment relating to th e varietal testing measure because there was no
scientific basis warranting the measure.
4.161 In other words, Japan had been unable to provide a risk assessment because there was no
scientific evidence that warranted testing by variety to achieve effective quarantine treatment against
codling moth. In particular, there was no scientific evidence supporting the necessity of varietal
testing (as opposed to testing by product) for quarantine treatment efficacy against codling moth with
MB and/or MB fumigation and cold storage. Japan contended that it was possible that varietal

differences within the same agricultural product might affect the efficacy of the treatment. 135 Faced
with the uniformly lethal efficacy of the quarantine treatment in all confirmatory tests and the dearth
of scientific evidence in support of varietal testing, Japan had offered descriptions of dose-response
variation in support of the measure. However, these descriptions ignored the conclusions of the
scientific studies done on quarantine treatments for codling moth, and abundant US empirical
evidence that there were no differences among varieties that affected efficacy of quarantine treatment.
The uniform success of treatments accepted by Japan also belied this notion.
136 The United States
noted that none of the small-scale dose-mortality studies and studies relating to CxT cited by Japan
constituted a risk assessment. Japan had never claimed otherwise. At most, these studies were
designed to provide data relevant to a risk assessment.
4.162 The United States noted that in its submission Japan had indicated that it performed an
individual risk assessment each time a country requested that the import ban be lifted for the product
(paragraph 4.145). Yet, for years the United States had sought the lifting of the ban for certain
products only to be thwarted by the varietal testing requirements of Japan. While Japan had indicated
that it was open to proposals other than varietal testing, experience had shown that there was little
flexibility to accept an equally effective alternative. The United States was unaware of any individual
risk assessment that had been done for apples, cherries, nectarines, or walnuts.
4.163 Japan maintained that an overall risk assessment relating to varietal testing had been
conducted. Japan held that the efficacy of any proposed alternative disinfestation treatment of host
plants had to be demonstrated by the exporting country. In fact, Japan stressed that the element which
needed to be based on a risk assessment was the substantive requirement that efficacy of disinfestation
treatment be demonstrated. The United States had not challenged the necessity of confirmation.
Falling short of such proof, Japan assumed that the initial risk assessment continued to govern in
respect of the pest and its host plants, and varietal testing would continue to apply. In other words,
the "risk assessment" relating to varietal testing wa s performed as part of the overall risk assessment
of the pest.
4.164 In terms of the PRA Guidelines, lifting of import prohibition could be understood as an
alteration of the quarantine measure (which constituted part of the "risk management" to be performed
in Stage 3 under the terminology of the PRA Guidelines, see paragraph 4.155).
137 It was the element
of "biological effectiveness" (paragraph 4.156) of the proposed treatment that Japan considered in
requiring demonstration of the absence of varietal difference of treatment efficacy.
4.165 Moreover, the "risk assessment" relating to varietal testing was made each time Japan
determined if a proposed treatment would ensure the required level of protection against the risk of
codling moth:
(a) when an exporting government sought approval of additional varieties (of apples, for
example), Japan investigated what alternative measure would achieve the required
level of protection;
(b) it was the responsibility of the exporting government to demonstrate that a treatment
(e.g., the existing treatment for other varieties) would achieve the level of protection;

135 In response to US Question 4 in consultations, Japan had stated: "It is possible there may be variation in the
efficacy of disinfestation even if the same quarantine treatment is applied to different varieties. For that reason GOJ requir es
that the efficacy of quarantine standards be confirmed". [emphasis added]. (US Exhibit 3)
 136 US Exhibit 2.
137 Japan noted that a conditional lifting of the import prohibition corresponded to an alteration of the measure
from "prohibition of entry of specific commodities from specific origins" to "definition of requirements to be satisfied before
export".

(c) available data suggested that efficacy of a treatment could vary depending on the
varieties;
(d) other factors listed in Article 5.2 were also considered to verify if any new
information was available; and,
(e) unless new discoveries in the above process had lead to a different conclusion, the
exporting government had to positively demonstrate either that varietal differences
would not affect the efficacy of a treatment, or that the treatment they proposed
would achieve the level of protection for other varieties by tests ("varietal testing").
4.166 Japan further argued that the Appellate Body in EC – Hormones, had discarded the notion of
a "minimum procedural requirement" from Article 5.1. Accordingly, all that was required was that an
SPS measure be based on a risk assessment which might be carried out by anyone. The fact that the
risk assessment had taken into account all relevant scientific factors and was consistent with FAO
PRA guidelines had been affirmed by Mr. Taylor.
4.167 The United States noted that Dr. Heather had explained that an assessment of the risk
associated with varietal differences, if any, w ould focus on two elements: (i) the interaction between
the physical and physiological characteristics of the product and the fumigant which resulted in higher
sorption in one variety than another; and, (ii) higher susceptibility of the product to pest which
resulted in consistently higher levels of infestation risk on one variety than another. There was no
indication in the document submitted by Japan (Japan, Exhibit 9) that either of these factors had been
considered. Furthermore, the United States recalled that Mr. Taylor had stated that the risk
assessment was sufficient to justify a measure to ensure that the pest was kept out of Japan, and not
the product. In other words, if an efficacious treatment had been established, Japan would not be
justified to continue to ban the product.
4.168 The United States also noted that, while compliance with the FAO Guidelines was not
dispositive in the case at issue, Japan itself had admitted in its submission that the risk assessment it
submitted related only to Stage 2 of the FAO Guidelines. Consideration of the need for quarantine
requirements such as Japan's varietal testing requirement would fall under Stage 3. The United States
noted that section 3.3 of the FAO Guidelines emphasi zed that "it is not justified to complete only
Stages 1 and 2 and then take phytosanitary measur es without [completion of Phase 3]." However,
Japan had done precisely this.
4.169 The United States concluded that no risk assessment existed with respect to the question of
whether differences in varietal characteristics could affect treatment efficacy. The varietal testing
requirement was thus not based on a risk assessment as required by Article 5.1. This was valid even if
Japan's Exhibit 9 was considered a risk assessment as that exhibit was not rationally related to the
varietal testing measure and did not reasonably support it since it contained no assessment of risks
attributable to varietal differences affecting treatment efficacy. Hence, as Japan had not assessed the
risk, consistent with Articles 5.1 and 5.2 of the SPS Agreement, it had no basis to make a scientific
determination about the potential for entry and establishment of codling moth in Japan. Because the
varietal testing requirement was not based on a risk assessment under Article 5.1, it necessarily was
not based on sufficient scientific evidence under Article 2.2 and was inconsistent with that obligation
as well.
4. Article 5.2
4.170 Serving as a guideline for evaluation of risk, the United States pointed out that Article 5.2
suggested that Members take into consideration "available scientific evidence; relevant processes and
production methods; relevant inspection, sampling and testing methods; prevalence of specific
diseases and pests; existence of pest- or disease-free areas; relevant ecological and environmental

conditions; and quarantine or other treatment". There was no evidence that Japan had complied with
this obligation. Japan had not taken into consideration the relevant risk factors for contamination by
the pest, which would necessarily include: an understanding of the growth patterns of the pest
138,
which products were considered to be preferred host of the pest, and what pre- and post-harvest
techniques were implemented to reduce levels of infestation.139 Although there was a significant body
of published information on these topics, the United States maintained that Japan had not factored any
of these considerations into their pest risk analysis. Neither had Japan given consideration to the
intended use of the product - which in the case of exported fruit was for consumption and not for
propagation.
4.171 Furthermore, contrary to Article 5.2, Japan had not examined relevant process and production
methods; prevalence of codling moth; or relevant environmental and ecological conditions as these
factors related to US apples, cherries, walnuts, and nectarines.
140 Had Japan engaged in such an
assessment of risk of introduction of codling moth to Japan, it might have examined the biology of the
codling moth to discern what stage was most tolerant to MB fumigation, what stage of tolerance of
the pest would be expected at harvest, and when if at all the codling moth would be most abundant on
a particular fruit product. Such technical issues were of value in developing the appropriate
quarantine treatment.
141
4.172 An assessment of risk might also have examined, as required under Article 5.2, the prevalence
of codling moth on US products. Codling moth was rarely found in exported US fruit mainly due to
the combination of integrated pest management (IPM) and production and post-harvest practices.
IPM practices included monitoring of moth activity to determine when generations appeared and in
order to predict when egg laying would occur. Us e of moth-trap catch data, combined with historical
and environmental data, permitted relatively accurate predictions of moth activity. These predictions,
plus field observations, dictated when and what type of control was necessary.
142 There were studies
that demonstrated that the presence of codling moth on US apples143 and on walnuts144 was relatively
limited; and that US cherries 145 and nectarines 146 were not preferred hosts of the codling moth. 147

138 US Exhibit 29.
139 US Exhibit 30.
140 Article 5.2 of the SPS Agreement indicated that when carrying out a risk assessment, "Members shall take into
account available scientific evidence; relevant processes and production methods; relevant inspection, sampling and testing
methods; prevalence of specific diseases or pests; existence of pest- or disease-free areas; relevant ecological and
environmental conditions; and quarantine or other treatment".
141 US Exhibit 29.
142 Jang and Moffitt, "Systems Approaches to Achievin g Quarantine Security" in Sh arp and Hallman, Quarantine
Treatments for Pests of Food Plants, West View Press, Boulder, San Francisco, Oxford, 1994, pp.225-237. (US Exhibit 7)
143 Moffitt, "A Systems Approach to Meeting Quarantine Requirements for Insect Pests of Deciduous Fruits," 85
Proceedings, Washington State Hortic. Association, 1989. pp.223-225. (US Exhibit 8)
144 Vail, Tebbets, Mackey and Curtis, "Quarantine Treatments: A Biological Approach to Decision-Making for
Selected Hosts of Codling Moth (Lepidoptera: Tortricidae)", 86(1) J. Econ. Entomol, 1993, pp.70-75, 72. (US Exhibit 9)
145 Ibid. (US Exhibit 9)
146 Curtis, Clark and Tebbets, "Incidence of Codling Moth (Lepidoptera: Torticidae) in Packed Nectarines," 84(6)
J. Econ. Entomol., 1991, pp.1686-1690. (US Exhibit 10)
147 US Exhibit 30.

Moreover, Japan had not taken into consideration the existence of uniform and effective US
quarantine treatments for the pest in the relevant fruit product. 148
4.173 The United States claimed, thus, that the document which Japan had asserted was its risk
assessment did not take into account the factors listed in Article 5.2. It did not, and could not,
demonstrate any objective or rational relationship between Japan's varietal testing requirement, on the
one hand, and scientific evidence of a phytosanitary risk on the other.
4.174 Japan noted that on this question of law, the United States seemed to argue that Japan's entire
pest risk analysis had not taken into account the factors listed in Article 5.2. In respect of available
scientific evidence, Japan claimed that the 1996 pest risk analysis had relied on the data set out under
Article 2.2, as they were available in 1996. In respect of relevant process and production methods,
Japan claimed that there were no known processe s or methods of cultivation which could avoid
codling moth completely. In respect of relevant inspection, sampling and testing methods, Japan
noted that there were no known inspection, sampling and testing methods, either by exporting
countries or by Japan, which would effectively detect and prevent introduction of the insect into
Japan. Japan had taken into account that the host fruits were for consumption. In respect of the
prevalence of specific diseases or pests, Japan had identified areas infested by pests, including the
United States, by available literature and other surveys. In respect of existence of pest- or disease-free
areas, Japan had not been able to obtain informati on regarding the presence of a pest-free area within
a country or area infested by the moth. Furthermore, relevant ecological and environmental
conditions – the biological characteristics of codling moth and the Japanese environmental conditions
had been examined, and it had been found that the insect could be successfully introduced and
established in Japan. Finally, in respect of quarantine treatment or other treatment, Japan recalled that
codling moth eggs or young larvae which entered into the fruits at the calyx were very difficult to
detect. Although no comprehensive quarantine treatment of host plants had been developed so far,
effective treatments had been established for certain varieties of American cherries, nectarines, in-
shell walnuts and apples, Canadian cherries, New Zealand cherries, nectarines and apples.
4.175 Japan further rebutted the US claims set out in paragraph 4.171: (i) Japan had considered the
biology of the codling moth in order to discern wh at stage was the most tolerant to MB fumigation –
this factor constituted the core of the "basic test"; (ii) in respect of the stage of tolerance of the pest
that could be expected at harvest, Japan noted that the test guidelines required exporting governments
to investigate development stages of the insect wh ich could be encountered at harvest, and that the
most resistant of possible development stages found on harvested fruits be tested for a treatment; (iii)
in respect of when the codling moth would be most abundant on a particular fruit product, Japan noted
that as the harvest season would not vary for a variety, variation in the number of individuals would
not affect the kinds of tests required.
4.176 In respect of the US claim that Japan had not taken into account the fact that codling moth
was rarely found in exported US fruit (paragraph 4.172), Japan noted that the concept of IPM was to
manage the insect population so that harmful populations be diminished and maintained at a level
lower than an economic injury level. By definition, it did not achieve the level of protection
equivalent to import prohibition. This risk would not be eliminated by import procedures alone, for
there was no inspection technique which would effectively discover the pest. Disinfestation had been
chosen in light of these considerations, and not because pre- and post-harvest techniques were
irrelevant. Furthermore, although the United States had pointed out that there were studies that
demonstrated that the presence of codling moth on US apples and walnuts was relatively low; and that
US cherries and nectarines were not preferred hosts to the codling moth (also in paragraph 4.172),
Japan noted that available literature confirmed the presence of codling moth in apples, walnuts,

148 US Exhibit 2.

cherries and nectarines. 149 In a previous case, dead larvae because of fumigation were found upon
inspection of exported cherries.150
4.177 The United States noted that the approach taken by Japan was to evaluate each factor on its
own to achieve Japan’s level of protection was a peculiar approach to risk assessment. The United
States claimed factors such as the biology of the codling moth, the prevalence of codling moth on
various US products, the scientific evidence and the empirical data, had to be viewed as
complementary factors and cumulative in effect to assess the risk of codling moth from US products
for export to Japan. This differed significantly from the position of Japan, which examined each
aspect of risk as a "zero sum" matter. In other words, if, as they had asserted, there was no inspection
process that completely accounted for the presence (or lack) of codling moth on exported products
then there was risk irrespective of the fact that the United States engaged in rigorous pre- and post-
harvest techniques to reduce the prevalence of codling moth in the first place.
F. ARTICLE 5.6
4.178 The United States argued that the Japanese varietal testing requirement was inconsistent with
Article 5.6 in that it was significantly more trade-restrictive than required to achieve the appropriate
level of phytosanitary protection. Article 5.6 required that:
"Without prejudice to paragraph 2 of Article 3, when establishing or maintaining
sanitary or phytosanitary measures to achieve the appropriate level of sanitary or
phytosanitary protection, Members shall ensure that such measures are not more trade-
restrictive than required to achieve their appropriate level of sanitary or phytosanitary
protection, taking into account technical and economic feasibility."
151
4.179 The United States noted that the "appropriate level of sanitary or phytosanitary protection"
was defined in paragraph 5 of Annex A of the SPS Agreement as: "The level of protection deemed
appropriate by the Member establishing a sanitary or phytosanitary measure to protect human, animal
or plant life or health within its territory." For the purpose of the dispute at issue, the level of
protection could be achieved by a certain rate of mortality of the pest (probit 9 level of mortality).
4.180 The United States noted that in order to fulfil the requirements of Japan, the United States had
conducted the testing procedure on seven varieties of apples, nine varieties of cherries, ten varieties of
nectarines, and four varieties of walnuts. The efficacy of the quarantine treatment had always been
shown in the confirmatory tests, in which the exact same treatment for the product uniformly achieved
Japan's level of quarantine protection irrespective of variety. The United States had never had to
modify a quarantine treatment for codling moth for varieties of the same product. Hence, according to
the United States, these results conclusively demonstrated that Japan's varietal testing requirements
had no value in providing additional quarantine protection.
4.181 The United States further claimed that the uniform experience of efficacy of treatment for
varieties against codling moth was not limited to th e United States. Japan had yet to identify any

149 Chapman, P.J. & S.E. Lienk, 1971. (Japan, Exhibit 25)
150 Japan noted that during the export inspection of 1997 cherries, four dead larvae had been found. Because the
sampling was conducted only on 1 per cent and it was difficult to fully discover the pest by inspection, Japan had assumed
that a fair number of fruits were infested.
151 The footnote to Article 5.6 of the SPS Agreement reads: "For purposes of paragraph 6 of Article 5, a measure
is not more trade-restrictive than required unless there is another measure, reasonably available taking into account technical
and economic feasibility, that achieves the appropriate level of sa nitary or phytosanitary protection and is significantly less
restrictive to trade".

instance where a quarantine treatment developed by any country (New Zealand, Australia, Chile,
South Africa, Spain, Israel, and others) for codling moth on fruit to be imported into Japan had been
changed for subsequent varieties. The United States maintained that no other country had ever had to
modify a treatment among varieties to achieve Japan's level of protection for codling moth.
Additionally, the accepted international practice in the area of pest quarantine treatment by virtually
every other country in the world was to require testing by product, not by variety. In this respect, the
United States noted that as an example, with respect to quarantine practices for all arthropods (pests),
the United States had for decades cleared fruit by pest and plant species, not by variety. In the
operation of these quarantine approvals by species, there had never been any indication of varietal
differences that required modification of the established treatment for the product. Therefore, it was
evident that testing by product (in which a treatment was established with one variety, or gr oup of
varieties, and then applied to all other varieties of that product subsequently sought for export),
provided an equal level of quarantine protection and was significantly less trade restrictive.
4.182 Article 5.6 was violated if there was a reasonably available alternative, taking into account
technical and economic feasibility, which achieved Japan's level of quarantine protection and was
significantly less trade restrictive. Because there were no varietal differences that affected the
efficacy of quarantine treatment, the same established treatment would achieve the appropriate level
of protection for all varieties of a product. The United States noted that testing by variety took a
minimum of 2-4 years to complete per variety, was resource intensive and costly to perform, and,
furthermore, seriously delayed market access of US products. On the other hand, testing by pr oduct
was significantly less trade restrictive. The Japanese requirement of varietal testing was significantly
more trade-restrictive than required, and testing by product was a reasonably available alternative
which achieved Japan's level of phytosanitary protection.
4.183 Japan stated that its lifting of import prohibition was indeed a result of the discharge of its
obligation under Article 5.6. Whenever Japan found a measure which achieved the appropriate level
of protection and was significantly less restrictive, the import prohibition was replaced with such a
measure. In this particular case, however, Japan had found data which suggested presence of varietal
differences in efficacy of MB fumigation, and a hypothesis which explained such a variation.
4.184 The United States had challenged Japan under the assumption that "[b]ecause there are no
varietal differences that affect the efficacy of quarantine treatment, the same established treatment
will achieve for all varieties of a pr oduct the appropriate level of protection". However, the US
evidence did not support their position; the United States had simply submitted a hypothesis which
not only cast doubt on laboratory results but on large-scale tests as well. Japan claimed that prior to
the lifting of the import prohibition on certain products subject to implementation of an alternative
measure, efficacy of the measure had to be demonstrated by the exporting government, and this was a
reasonable requirement in light of the asymmetric presence of information on exotic pests and goods.
As the United States had not proven species-wide efficacy, Japan was not obliged to accept their
alternative at this stage.
4.185 Japan pointed out that it had nevertheless made efforts to alleviate the burden of exporting
governments. Japan had accepted the concept of a representative variety. This was why there was no
requirement of a full-scale testing of each variety. In additions, for approval of additional varieties,
the size of samples in large-scale demonstrations had been reduced from 30,000 to 10,000 insects.
4.186 The United States noted that other than recognition of pest-free zones or eradication of a pest
from a region or country, Japan had never accepted an alternative to its varietal testing regime with
respect to codling moth or other pests of similar significance to Japan. The United States stressed that
it considered testing by product as the only acceptable quarantine measure in the context of the
dispute at issue. It was acceptable that the first variety of a particular product from any source should
be subject to the full range of testing. Japan's required procedures for the development of a
quarantine treatment included a large-scale test with sufficient numbers of insects to validate that
treatment for the product. After such validation, no further testing was necessary for additional

varieties. The United States claimed that to be required to treat 10,000 insects and to use the
necessary quantity of fruit for each additional variety would be virtually as time-consuming and
burdensome as the current requirement to do dose-mortality tests for each variety and confirmatory
testing on representative varieties. Hence, to accept the requirement of confirmatory tests on each
subsequent variety would be tantamount to acknowledging that varieties made a difference in the
ultimate efficacy of MB quarantine treatment for codling moth, a notion unsupported by scientific
evidence, data, or principle.
G. A
RTICLE 5.7
4.187 Japan claimed that varietal testing could be considered a provisional measure. The rationale
of the present policy to require efficacy confirmation on a variety basis was that available evidence
suggested a possible presence of varietal differences in the efficacy of disinfestation treatment. This
policy was based on a scientific hypothesis, it did not presume, a priori, varietal differences in all
circumstances. Import prohibition could be lifted on a product basis subject to sufficient
demonstration. As an example, in respect of fruits whose varietal difference was attributed to bud
mutation (e.g., lemons), and no major differences were anticipated, a single treatment would ensure an
appropriate level of protection for all varieties of the product.
4.188 Once the import prohibition had been lifted on a particular variety subject to a disinfestation
treatment, new data would be accumulated on the effects of a treatment or on the characteristics of
prohibited items, and it would then be possible to reach a level of confidence on broader applicability
of the existing treatment. This was a reasonable assumption; however, until that had been achieved,
Japan insisted on its right to maintain the prohibition, on a provisional basis, on importation of the
other varieties. Japan based its measure on available pertinent information as set out in its risk
assessment and recognized that the importing gove rnment was required to "seek to obtain the
additional information necessary for a more objective assessment of risk and review the …
phytosanitary measure accordingly within a reasonable period of time" (Article 5.7).
4.189 The United States noted that it had been engaged in detailed negotiations with Japan for over
two decades. Although Japan had chosen to present a risk assessment on an undisputed matter, Japan
was intimately aware of the evidence that had been discussed in the US submissions and what the
evidence signified. That evidence was relevant and sufficient, and specifically addressed the specific
mortality level of codling moth required by Japan. The United States had firmly established that
efficacy of treatment by product achieved Japan’s required level of mortality. The varietal testing
requirement could not be characterized as a provisional measure - invocation of Article 5.7 was not a
supportable claim.
4.190 The United States pointed out that although Japan claimed it believed it had presented sufficient
scientific evidence to meet the obligations of Articles 2.2 and 5.1, Japan also claimed that the measure
nonetheless was a provisional measure. These two positions were diametrically opposed. Indeed,
Article 2.2 listed Article 5.7 as an exception to its requirements, because it was considered that Article
5.7 would permit a measure to be applied even where the "sufficient scientific evidence" requirement of
Article 2.2 was not met. Similarly, Article 5.7 applied only where the relevant scientific evidence was
insufficient to permit a risk assessment. Consequently, the United States argued that Japan’s claim that
it had enough evidence to satisfy the requirements of Articles 2.2 and 5.1 with respect to its ban meant
that Japan’s ban failed to meet the threshold requirement of Article 5.7. Moreover, the United States
claimed that this was not a situation in which there was insufficient scientific evidence, because there
was no evidence supporting Japan's claim that variety mattered, and because all evidence in the case at
issue, including the success of uniform treatments of different varieties exported to Japan and the
absence of failures by product-based testing regimes in other countries, indicated that varietal
differences did not affect treatment efficacy.

4.191 The United States noted that the measure had gone into effect 48 years ago. Therefore, the
measure could hardly be called "provisional". Moreover, there was no evidence that Japan had
undertaken a process to yield "within a reasonable period of time" a more objective assessment of risk
so that it could review whether the "provisional m easure" should be continued. Japan had therefore
failed to meet the requirement of Article 5.7 that an objective risk assessment be done within a
reasonable time.
H. ARTICLE 7 (ANNEX B)
4.192 The United States argued that the Japanese measure lacked transparency, and was thus
inconsistent with Article 7. Article 7 and Annex B set out a number of requirements that Members
had to follow in regard to transparency of an SPS measure. Specifically, Annex B, paragraph 1
required that "Members shall ensure that all sanitary and phytosanitary regulations which have been
adopted are published promptly in such a manner as to enable interested Members to become
acquainted with them". The United States had made a specific request to the Enquiry Point for Japan
which had admitted that there was no published source for varietal testing. 152 The measure had been
developed over time through a series of protocols and practice.
4.193 The United States noted that the lack of transparency was made more evident by the lack of a
risk assessment on the varietal testing measure. Had the measure been based on scientific principles,
maintained with sufficient scientific evidence, based on an assessment of the risks, and not
significantly more trade-restrictive than required to achieve the appropriate level of protection, it
would have been possible to justify in a transparent fashion the legitimacy of the measure. As the
requirement of varietal testing could not fulfil any of these WTO requirements, it was not surprising
to find that the measure lacked transparency.
4.194 Japan noted that the claim of the United States related to the guidelines developed by the
MAFF concerning confirmation of efficacy of disinfestation treatment.
153 These had been distributed
to foreign plant quarantine authorities for the purpose of transparency. The contents of the guidelines
were not mandatory and exporting governments could choose to demonstrate efficacy of treatment by
other means. Consequently, these guidelines did not fall under the concept of "regulations" under
paragraph 1 of Annex B. In other words, they did not constitute enforceable regulations covered by
Article 7. Nevertheless, these guidelines were available to any interested foreign government through
Japan's Enquiry Point, consistent with paragraph 3(b) of Annex B.
4.195 The Annexed Table to the Enforcement Regulation identified the quarantine pest which
constituted the cause of the import prohibition, the countries or areas from which importation was
prohibited, and the prohibited host plants and their specific parts. Japan pointed out that this allowed
any exporter of agricultural products to know in advance which items were prohibited, as well as the
quarantine pests concerned. In contrast, other countries, including the United States, generally
prohibited importation of all plants and chose a quarantine measure on the basis of a risk analysis only
after the filing of an import permit. Under such a mechanism, a foreign exporter was not able to know
in advance whether or not the products were exportable, and which quarantine pests had to be guarded
against. In this sense, Japan claimed that its regulations were characterized by a greater degree of
transparency.
4.196 The United States claimed that the assertion by Japan that these were simply "guidelines"
and not "regulations" was a novel claim, and one that departed from the issue at hand. In
consultations Japan had indicated that while the varietal testing requirement was not published, the

152 Japan's response to Question 2 of US Consultation Questions. (US Exhibit 3)
153 Contained in Japan, Exhibit 10.

lifting of an import ban was based on specific legislation. Irrespective of the informal process by
which US scientists, in consultation with Japan, had devised procedures to test by variety 154 the fact
remained that the requirement itself - that which linked the import prohibition with the requirement
that it could only be lifted by variety - had to be published.
4.197 The United States argued that the issue of transparency was indicative of a much larger
problem. The requirement at issue arose from specific legislation and regulations and yet there was
no published source that explained what procedures were necessary to have a product removed from
the import prohibition list. The United States , the European Community and numerous other
exporting countries had no access to phytosanitary protocols in which Japan had already negotiated
and approved treatment for a particular product.
155 In short, without publication of this information,
an exporter had no way to discern what was necessary to move a product from the prohibited list to a
list approved by Japan for entry. The purpose of transparency was to ensure that Members were
carrying out their obligations under the SPS Agreement. An absence of transparency contributed to
the overall impression that this measure was far from being consistent with those obligations.
4.198 In respect of transparency, Japan noted that anyone who wished to be informed about
approved phytosanitary protocols for approved items could refer to MAFF notifications, published in
the Government Gazette. If these were difficult to locate, the MAFF could be contacted directly.
I. ARTICLE 8 (ANNEX C)
4.199 The United States claimed that as a matter of control and inspection procedures, the Japanese
measure was inconsistent with Article 8. The United States noted that sub-paragraphs (a) through (i)
of paragraph 1 of Annex C did not replace any of the requirements of Articles 2, 5, and 7, but
complemented them by imposing additional, more specific disciplines on Annex C measures. An
Annex C measure therefore could be in breach of Articles 2, 5, 7, and 8. However, if an Annex C
measure was inconsistent with Articles 2 and 5, as was the case with the Japanese measure at issue,
then it was not a legitimate sanitary or phytosanitary measure. To a certain extent, then, the
requirements of Annex C.1(a)-(i) would be secondary with respect to such an illegitimate measure
since, under the SPS Agreement, the measure could not be maintained in the first place.
4.200 Article 8 and Annex C set out several standards that Members had to observe in the operation
of control and inspection. The varietal testing requirement was such a procedure because Japan
required control and inspection of the quarantine treatment of a variety of a product before it could be
approved for export into its country. The exporting country had to provide certification that the
quarantine treatment applied to the variety in question achieved the appropriate phytosanitary level of
protection of Japan.
4.201 Annex C, paragraph 1(c) required that Members limit information requirements to "what is
necessary for appropriate control, inspection and approval procedures". Yet, because the varietal
testing requirement was not based on scientific principles, was maintained without sufficient scientific
evidence, was not based on an assessment of the risks, and was more trade-restrictive than required to
achieve the appropriate level of protection, Japan's measure was inappropriate.
4.202 Japan noted, in respect of paragraph 1(c), that the information required was what was
necessary to demonstrate the efficacy of a treatment. Japan recalled that it did not necessarily demand
complete testing of each variety (paragraph 4.31). The requirement under paragraph 1(c) was

154 The United States noted that these had been printed for the first time in a hand-out in Japan's Exhibit 10.
155 Third Party Oral Statement by the European Community, paragraph 8.

consequently fully met. Nevertheless, Japan remained willing to consider more appropriate ways to
fulfil the informational requirements of exporting governments.
4.203 The United States further argued that Japan had, contrary to Article 8 and Annex C,
paragraph 1(h), not limited the required procedures for a "modified product" to what was "necessary
to determine whether adequate confidence exists that the product still meets the regulations
concerned". The United States claimed that a requirement that allowed for uniform treatment for a
product without testing by variety would be an appropriate limitation. To require the United States to
provide information on the efficacy of treatment for every variety when there was already an existing
and efficacious treatment for the product was not limiting Japan's information requirements to what
was necessary.
4.204 While there were no differences among varieties of a product that affected efficacy of
quarantine treatment, there were any number of varieties that were developed for the purpose of
improving marketability. The difference could be as benign as improving the color or inducing
ripeness more quickly. A variety of nectarine coul d be modified so it ripened one week faster than
another variety. A variety of cherry could be modified so that it had a more vibrant color. A variety of
apple could be modified so that it tasted sweeter than another variety. While these were modifications,
they did not represent a difference in variety such that it affected efficacy of treatment. These
modification were therefore not a change in the sp ecifications of the product for purposes of efficacy
treatment for codling moth. The United States had de monstrated that variety did not affect efficacy of
MB quarantine treatment. Accordingly, no "further procedure" was "necessary" within the meaning of
paragraph 1(h) of Annex C for new varieties. Thus, Japan's measure at issue, which did require further
procedures for new varieties, was inconsistent with paragraph 1(h) because it went far beyond what was
"necessary".
4.205 In respect of consistency with paragraph 1(h), Japan pointed out that the issue of whether
different varieties fell within the concept of 'modified products' had to be addressed. Japan claimed
that such changes typically referred to alterations of additives or ingredients in processed foods and
did not cover varietal differences. Even if the provision were to apply to varietal differences, under
the Japanese system, required information was limited to what was "necessary to determine if it is
able to obtain sufficient confidence of conformity" of additional new varieties to those approved
subject to the quarantine treatment. Japan did not require varietal testing on "modifications of the
product" as long as it was demonstrated, based on scientific evidence, that they "represent the sort of
variability that in no way affects how effective the quarantine treatment will be at killing the plant
pests of concern", as set out by the United States in paragraph 4.23. Even if varieties were "modified
products", Japan considered that different varieties had to be tested to "determine whether adequate
confidence exists" and that the "modified products" still met the regulations concerned. Moreover,
Japan noted that the requirements of confirmation at the time of approval of additional varieties were
far less rigorous than the requirements which applied to the initial lifting of the import prohibition. In
this sense, the Japanese policy was fully consistent with paragraph 1(h). Japan noted that if there
were "no differences among varieties of a product th at affect efficacy of quarantine treatment" no
demonstration would be required, by tests or otherw ise. Japan was therefore in full conformity with
paragraph 1(h) of the Annex C.
4.206 Regarding the definition of "modified products", the United States noted that, contrary to
Japan's assertion, Annex C nowhere circumscribed or narrowed the scope of the phrase "modified
products" to mean "alterations of additives or ingredients in processed foods". The text of
paragraph 1(h) provided no basis for exclusion of the products at issue.

V. SUMMARY OF THIRD PARTY SUBMISSIONS
A. BRAZIL
5.1 Brazil noted that its interest in the dispute derived from its own experience in dealing with
Japanese import prohibition and quarantine requirements for fruits under the Plant Protection Law and
the Enforcement Regulation. Japan constituted an important potential market for Brazilian products.
Since 1986, Brazilian authorities had been in consultations with Japan with a view to initiating
exports of Brazilian mangoes to Japan, which were currently prohibited under the cited legislation.
5.2 In order to eradicate an insect that was of concern to Japanese authorities (the Mediterranean
fruit fly, or ceratitis capitata ), Brazil had undertaken the necessary research and had developed a
treatment of immersion in hot water for the Tommy At kins variety of mangoes. The test results had,
in Brazil's view, met Japan's requirement eliminating 30,000 individuals of the pest. Yet Brazil had
still not received authorization to initiate exports. Japanese authorities had requested that Brazil use a
treatment of hot vapour, which was ten times more expensive than the treatment based on immersion
in hot water. Brazil had not understood the reasoning behind this request, since the treatment that had
been tested and adopted had been proven to be successful and was currently being utilized by another
exporter of mangoes to Japan (Mexico) for treatment against the same insect. Brazil believed that the
case of the mango could prove to be useful to the Panel, since the import prohibition was based on the
same legislation that was used by Japan to establish quarantine treatments and import prohibitions for
the fruit varieties that were of direct interest to the United States. Brazil was still pursuing a bilateral
solution to the problem, in accordance with the principles set out in Article 3.7 of the DSU.
5.3 On the core issue of varietal testing requirements, Brazil shared the views expressed by the
United States that testing by product (commodity-by-commodity) was an alternative measure that was
reasonably available and was significantly less trade restrictive. In more general terms, Brazil noted
the long history of bilateral negotiations that were necessary to permit the importation of different
varieties of fruits into Japan. In the case of a developing country like Brazil, which was still
negotiating the lifting of an import prohibition on a single variety of a fruit, this was a precedent that
certainly did not reflect the balance of rights and obligations under the SPS Agreement, and
specifically the operation of the Articles cited by the United States in its complaint.
5.4 In the case before the Panel, there were clearly differences of view concerning such key
issues as "risk assessment", "sufficient scientific evidence", "scientific justification" and "appropriate
level of protection". There was also an important discussion, from Brazil's point of view, concerning
the recourse to alternative measures and the need to avoid discriminating or trade restrictive SPS
measures.
5.5 In respect of Articles 2 and 5 of the SPS Agreement, Brazil attached special importance to the
issue of necessity and to guaranteeing that measures were based on scientific principles and not
maintained without sufficient scientific evidence. These guidelines, alongside the obligation not to
discriminate, were important guarantees to avoid SPS measures that resulted in a "disguised
restriction on international trade". Article 5 of the SPS Agreement spelled out, in detail, the elements
that had to be taken into consideration in analyzing the necessity for a measure and in deciding on the
nature of the measure.
5.6 The treatment advocated by Brazil to combat the Mediterranean fruit fly was used by another
WTO Member for the same product for export to the Japanese market. Nevertheless, Brazil had been
called upon to use another treatment, which was more expensive. While Brazil remained ready to
cooperate with Japanese authorities, it noted that it had not yet received adequate explanations - of
scientific or other nature - as to the reason for not being accorded the right to use a quarantine
treatment that had been proven to be effective in tests conducted by Brazil and which were accepted
by Japan for exports of another Member affected by the same pest. It was Brazil's belief that Japanese

authorities had to take into consideration the concepts of a reasonable (and cost-effective) available
alternative and of non-discrimination.156 Brazil also questioned whether the minimization of negative
trade effects was being taken into consideration by Japan.
5.7 Since the provisions of Articles 2 and 5 of the SPS Agreement spelled out a series of
guidelines that had to be followed both in dividually by Members and in cooperation between
Members concerned, one of Brazil's major concerns was the issue of threshold in the application and
interpretation of these provisions. This was more so due to the fact that in the operation of the Plant
Protection Law and of the Enforcement Regulation, Japan insisted that the burden of proof, relating to
the acceptability of a substitute disinfestation measure (equivalent to an import prohibition), rested on
the exporting Member.
5.8 The issue of burden of proof - scientific evidence or scientific justification - and of different
interpretations of results recorded in scientific tests constituted an important part both of the US and
of the Japanese submissions concerning the need for varietal testing. While Brazil did not wish to
comment on the specific discussion of the significan ce of the statistical differences recorded in the
laboratory tests referred to by both parties, it was concerned with the extent to which an exporting
country had to go in order to confirm the validity of a specific measure, especially in light of its
current experience in the consultations related to tests to prove the efficacy of treatment for the
Mediterranean fruit fly in Brazilian mangoes. Since Japan itself recognized that most information was
received from the exporting Member, Brazil believed that the concept of equivalence, which was
contained in Article 4, should also be taken into consideration in the examination of information
provided concerning the pest and the proposed method of treatment.
 157
5.9 The correct implementation of the provisions of Articles 7 and 8 of the SPS Agreement
concerning transparency and standards for control and inspection were a further guarantee against
unnecessary burdens imposed on exporting Members. Brazil noted the reservations of the United
States in relation to the implementation by Japan of these two provisions, especially the problem of
lack of sufficient transparency of the SPS measure which Brazil had also experienced. Since Brazil
did not yet export mangoes to Japan, it was not in a position to provide its experience with Article 8
requirements, but, since its future exports would be affected by the same procedures, it was concerned
with what seemed to amount to unnecessary information requirements.
5.10 Brazil did not question Japan's right to implement sanitary and phytosanitary measures.
Brazil was also aware of its rights under Article 5.8 of the SPS Agreement. The objective of Brazil's
participation as a third party in the Panel proceedings was to express its concern with the possibility
that measures designed to protect plant health were being implemented without the necessary
justification and in such a way as to create negative trade effects or even as to constitute disguised
barriers to trade.
B. E
UROPEAN COMMUNITIES
The factual and scientific aspects of the case
5.11 The European Communities noted that it would comment on the factual and scientific aspects
of the case on the basis of its experience in its attempts to export fresh fruits and vegetables to Japan.

156 Brazil noted that the United States had referred to discrimination in relation to Japanese domestic production of
fruits. However, Brazil's present concern was related to disc rimination in relation to other WTO Members that exported to
Japan.
157 Brazil noted that although Article 4 was included in the terms of reference of the Panel, it had not been cited by
either of the parties to the dispute in their first submissions.

The task was particularly difficult as the first written submissions of the parties contained several
conflicting statements on a number of crucial scientific issues. The following aspects of the dispute
would be addressed:
(a) the issue of varietal testing of quarantine treatment efficacy against codling moth;
(b) the questions raised by the practice of Japan to require varietal testing for certain
types of fruits and pests;
(c) the complexity and lack of transparency of the Japanese system of procedures for
granting import authorization for fruits and vegetables; and,
(d) the hindrance to trade which could be a consequence of such repeated varietal testing
as applied by Japan.
5.12 The European Communities noted that it had experienced a number of difficulties in its
attempts to export fruits and vegetables to Japan and that many of these difficulties arose from a
variety of causes linked to the system of phytosanitary measures enacted by the Japanese authorities.
The European Communities was directly affected by the measures which the Panel was being asked to
consider: for example, authorization was granted in August 1997, after several years of testing and
discussion, to allow France to export Golden Delicious apples to Japan. However, if France wished to
export any other variety of apple in light of consumer reaction to its Golden Delicious already
shipped, the whole approval procedure would have to start anew.
5.13 The European Communities wished to underline that it did not contest the right of Japan, or of
any other Member, to protect plants within its territory from the introduction of harmful pests.
Indeed, the European Communities operated its own system of measures to protect plant health in full
accord with the terms of the SPS Agreement.
5.14 At issue was the conformity with the SPS Agreement of the requirement for varietal testing to
prove the efficiency of disinfestation for quarantine pests. In this regard, the European Communities
questioned the scientific basis of Japan's application of varietal testing for these purposes. While the
application of particular treatments could vary a little for different varieties of the same fruit or
vegetable, for example, due to the inherently different physical characteristics of the varieties (as in
the example of mangoes pointed out by Japan), the European Communities questioned the need of
requiring a completely new series of tests for a different variety of the same fruit or vegetable.
Varietal testing could be justified if the characteristics and other properties of the varieties in question
were such that differences could be expected which were relevant for the objective to be achieved.
However, it appeared to the European Communities that the measure in question was applied to an
extent beyond that which was necessary to protect plant life and health.
5.15 The European Communities second concern with regard to varietal testing was the apparent
lack of consistency in its application by the Japanese authorities. The attention of the Panel had been
drawn by the United States to the requirement of varietal testing in relation to apples, cherries,
nectarines and walnuts. However, for other varieties of pests and fruits and vegetables import
authorization seemed to have been granted without reference to full varietal testing. In the experience
of the European Communities, import prohibition in certain instances was lifted for all varieties at
once, while it was evident from the facts of the disp ute at issue that this was not the case for other
products. The European Communities was unaware of any explanation on the part of Japan of such a
differentiated application.
5.16 A third issue that the European Communities raised concerned the low degree of transparency
and high degree of complexity of the particular part of the Japanese phytosanitary regulatory system
at issue. The European Communities had asked, in recent deregulation requests, for a flow chart of
approval procedures for import authorization of plants and plant products. Japan had also been asked
to simplify and provide greater transparency of approval procedures for fresh fruit and vegetables. To
date, these requests had not been fulfilled. In fact, the import authorization procedure was not clearly

defined from beginning to end and normally proceeded on a step-by-step basis, with Japan defining
the successive steps; as soon as one hurdle was ov ercome another appeared on the list. The whole
process usually took several years, even before a trial shipment was allowed. Moreover, it involved
extensive series of tests, numerous visits to Tokyo for discussions with Japanese experts, public
hearings and extended on-site inspections by Japanese experts in the country wishing to export. It
was likely that the chances of exporting agricultural products to Japan would be improved if Japan
were willing to make available the phytosanitary protocols which it had negotiated with one country
to any other interested Member of the WTO.
5.17 The system of varietal testing as applied by Japan appeared to impede trade. The heavy
procedural requirements of Japan imposed a considerable burden on the exporting country, both in
terms of manpower, time and money. Under the system of varietal testing, exporters had to take the
risk of selecting a particular variety and endure a lengthy and complex procedure to gain approval.
Yet, if the initial assessment of Japanese consumer reaction were proven wrong, then the investment
of time, money and manpower would be wasted and the procedure had to be started all over again for
another variety. This appeared to be further compounded by the fact that Japan did not seem to allow
for testing and approval procedures to take place for several varieties at the same time. All this
represented a serious deterrent to those exporters wishing to gain a foothold in the Japanese market
for particular types of fruits and vegetables which had not been previously exported to that market.
Comments on the legal aspects of the case
Burden of proof
5.18 The European Communities considered that the di spute raised the issue of burden of proof.
This was a particularly complex problem in cases where science and law interacted. The allocation of
the burden of proof was an important legal question which could directly affect the outcome of a
dispute settlement procedure. It was recalled that the Appellate Body had pointed out that the initial
burden rested on the complaining party, which had to establish a prima facie case of inconsistency
with a particular provision of the SPS Agreement. When the prima facie case was made, the burden
of proof moved to the defending party, which had to counter or refute the claimed inconsistency.
158
5.19 "Burden of proof" was an ambiguous term. It was important to distinguish between: (1)
burden of producing evidence, (2) burden of persuasion, and (3) minimally sufficient evidence. These
concepts applied to very different aspects of fact-finding and responded to very different situations.
5.20 First, with respect to any factual issue, there could be various burdens of producing evidence
placed on parties. Under the DSU structure, a panel was not an investigative institution with the
capacity to generate its own evidence. There had to be rules concerning which party had to produce
evidence before the Panel and how much evidence had to be produced in order for the party not to
suffer adverse findings by default. Initially, a complaining party had to " present evidence and
argument sufficient to establish a presumption " ( prima facie case) that a Member had acted
inconsistently with its obligations under the SPS Agreement.
159 That is, the complaining party had to
produce sufficient evidence on any factual issue essential to its claim that a violation was occurring.160
Evidence had to be produced: (i) that was sufficient to support its requested finding, and (ii) that
would be sufficient to persuade the Panel that what was claimed was true, if no counter-evidence were

158 EC - Hormones, paragraphs 98, 108-109.
159 The United States – Measures Affecting Imports of Woven Wool Shirts and Blouses from India ,
WT/DS33/AB/R, adopted on 23 May 1997.
160 Appellate Body Reports on EC - Hormones and Indian Woven Wool Shirts and Blouses.

to be produced. A prima facie case had, therefore, to be of sufficient weight to persuade the Panel
and of sufficient quality to pass appellate review for reasonableness.
5.21 Second, the Panel would have to assess all the evidence for and against any factual
proposition and should adopt the proposition as a finding only if the evidence supported the
proposition. What was required was a determinati on by the Panel that the proposition at issue was
more likely to be true than false. On any factual issue there had to be a "default rule" for making a
finding when the weight of evidence was in "equipoise" - that is, when it appeared to the Panel that
the evidence for a proposition seemed equal in weight to the evidence for its negation. The party with
the burden of persuasion was the party who had to suffer an adverse finding unless it persuaded the
Panel to its view by a preponderance of the evid ence. It did not seem correct, however, to speak
(despite the practice and conventional wisdom) of any definitive or permanent "shift" in the burden of
proof in such a case, because the proof obligations of both parties continued ("back and forth")
throughout the entire litigation process.
5.22 Third, a panel was not authorized to make a find ing if there was not, in the record before it,
minimal evidence that any reasonable person would consider necessary to support such a finding.
5.23 In the present case, the United States argued effectively that the confirmatory tests were the
relevant indicator of efficacy of quarantine treatment. Japan contested this by arguing that its policy
of requiring confirmation on a varietal basis was supported by available evidence that suggested a
possible presence of varietal difference in the efficacy of disinfestation treatment (MB fumigation).
This was a scientific question and it was not clear whether the Panel would be able to resolve it, even
with the assistance of scientific experts.
5.24 Japan also contested the US argument that it required complete testing and review of each
variety. Yet, Japan did not deny that large-scale testing was required for initial lifting of the import
prohibition as well as for additional approval, if the results of the dose-mortality tests were
unsatisfactory. Japan did not deny that on-site confirmatory tests for one representative variety was
required for additional varieties, even if dose-mortality tests were confirmed. Japan also admitted that
dose-mortality tests were required in all cases for all varieties for initial and additional lifting of the
import prohibition. Nevertheless, Japan had not provided, in the view of the European Communities,
any reasonable response to the US argument that it (or any other country that applied a quarantine
treatment for codling moth on fruit to be exported to Japan) had never had to modify a quarantine
treatment for codling moth for varieties of the sa me commodity. The reply of Japan that they had
accepted that the proposed treatment (on Hartley walnuts) would disinfest codling moth to the
satisfactory level (not because varietal differences were irrelevant) was not convincing. Japan needed
to bring forward minimally sufficient evidence to convince the Panel that varietal differences did
affect, for each product in question, the fumigation efficacy. It did not seem enough to argue that this
was a reasonable hypothesis or argument, as posited by Japan.
5.25 Moreover, the European Communities pointed out that it did not share the interpretation made
by Japan of the EC - Hormones case. Contrary to what Japan appeared to argue, the European
Communities had not "only asserted that safety of hormones was not proven beyond doubt".
161 The
Appellate Body Report on EC - Hormones clarified that the European Communities did "indeed show
the existence of a general risk of cancer" and that its studies were "relevant but do not appear to be
sufficiently specific to the case at hand".
162 It was clear also from other parts of the Appellate Body
Report on EC - Hormones that the issue there concerned the incorrect interpretation made by the

161 This was, according to the European Communities, the wrong interpretation of EC arguments made by the panel.
162 Op. cit., paragraph 200.

United States and the panel of the concept of risk under Article 5.1 of the SPS Agreement, as
requiring a certain magnitude or threshold level of risk to be demonstrated in the risk assessment. 163
5.26 The European Communities considered that what Japan needed to prove in this particular
case, in light of the evidence brought by the United States, was that its risk assessment sufficiently
warranted or reasonably supported the SPS measure at stake. 164 It was necessary for Japan to
establish the rational link between the measure and its risk assessment.
The Panel's role in reviewing the scientific judgments made by WTO Members
5.27 Under the DSU rules, the Panel had to decide whether the Japanese measures were based on a
risk assessment as appropriate to the circumstances (Article 5.1). The Panel should also judge
whether these measures were based on scientific principles and were maintained with sufficient
scientific evidence (Article 2.2). In this regard none of the parties to the dispute had attempted to
shed any light on the interpretation to be given to the concept of "sufficient scientific evidence" in
Article 2.2 of the SPS Agreement.
5.28 In respect of the standard of review the European Communities noted that the Appellate Body
had clarified in EC - Hormones that the Panel should make "an objective assessment of the facts". 165
A panel could not conduct its own risk assessment. With respect to any of the many scientific issues
involved in the risk assessment conducted by a WTO Member, a panel could not substitute its own
scientific judgment for that of the WTO Member applying an SPS measure. It appeared also that
panels should not substitute the scientific judgment of individual scientists or experts, which might be
chosen by it in accordance with Article 11 of the SPS Agreement, with that of the WTO Member that
carried out the risk assessment. A panel's mandate in considering the evidence invoked by a WTO
Member maintaining an SPS measure was not to determine whether it agreed that such evidence
constituted the "best evidence" available, but merely to determine whether that Member's risk
assessment sufficiently warranted or reasonably supported the measure at hand.
Arbitrary, unjustifiable or disguised restriction on international trade
5.29 In accordance with Articles 2.3 and 5.6 of the SPS Agreement, the European Communities
believed that the United States bore the burden of showing that the Japanese measures were arbitrary,
unjustifiable or constituted a disguised restriction on international trade. In particular, the United
States had to show that there was another reasonably available measure which was less restrictive on
trade and which could achieve the level of protection chosen by Japan.
5.30 In this respect the European Communities observed that, with regard to the varieties of
apples, cherries, nectarines and walnuts of US origin which had already been approved for export to
Japan, the same varieties coming from another WTO Member should also be allowed to be imported
into Japan on the same conditions. As Article 2.3 of the SPS Agreement provided, Members should
not arbitrarily or unjustifiably discriminate between Members where identical or similar conditions
prevail. Therefore, another WTO Member wishing to export the same varieties of products to Japan
should be given the opportunity to show that indeed identical or similar conditions prevailed in
respect of the varieties in question.

163 Op. cit., paragraphs 184-186. The European Communities noted that this discussion was linked to the concept of
"zero risk" policy, which was not summarized at all in the Appellate Body Report on EC - Hormones.
164 Op. cit., paragraph 193.
165 Ibid., paragraph 117.

Conclusion
5.31 The European Communities was of the view that the varietal testing system of Japan was too
cumbersome and appeared to be applied in a manner which was more restrictive than necessary to
achieve its stated objective. The Japanese system was also characterized by lack of transparency
which could further impede trade in such products.
C. HUNGARY
5.32 Hungary noted that Article 2.1 of the SPS Agreement clearly stipulated the right of Members
to take phytosanitary measures which were necessary for the protection of plant life or health.
Nevertheless this right was conditional upon the fulfilment of all relevant provisions of the
Agreement. Pursuant to Article 2.2, Members were obliged to "...ensure that any ...phytosanitary
measure is applied only to the extent necessary to protect ... plant life or health, is based on scientific
principles and is not maintained without sufficient scientific evidence...". An exception to the latter
provision was provided for in Article 5.7.
5.33 According to its submission, Japan had conducted a full-scale risk assessment concerning the
plant quarantine measures in operation, including with respect to codling moth. However there was
no indication as to whether, in accordance with Article 5.1, any risk assessment of the varietal testing
of codling moth had been performed. Indeed, Japa n's main argument with regard to the scientific
rationale of varietal testing seemed to relate to the variation of the CxT values between varieties (in
MB fumigation test on codling moth). Japan apparently interpreted this variation as an indicator of
the degree of efficacy of the fumigation treatment.
5.34 It was Hungary's view that Japan had neither be en able to show unequivocally that variation
of CxT values was a direct function of varietal differences nor had Japan established unambiguously
that differences in CxT values necessarily affected the efficacy of the fumigation treatment at issue.
At the very least this had been partly acknowledged by Japan when it argued the possibility of a
"presence of varietal difference in the efficacy of disinfestation treatment".
166 Also, Japan had stated
that its policy was based only "on a scientific hypothesis". 167 On the basis of available scientific
knowledge, Hungary agreed with US arguments which questioned the scientific justification of
varietal testing, in that: (i) minor differences in CxT values between varieties did not indicate
differences in varieties of a single commodity; (ii) test-to-test variation of one variety was as great as
that found between varieties; and, (iii) studies had indicated that the same variety of a commodity
could show variations in dose-mortality tests from crop year to crop year, or even according to the
stage of ripening of the particular variety. Hungary believed that the fact that there had not, to date,
been any instance where the complaining party had ha d to modify a quarantine treatment for codling
moth for varieties of the same commodity was of pa rticular relevance to the dispute as it appeared to
constitute strong evidence of the effectiveness of the established fumigation treatment across the
different varieties of fruits. On the basis of the Japanese line of reasoning, it would be just as natural
to expect numerous cases where modifications of treatment would have been required.
5.35 Hungary maintained that the evidence put forward by the United States clearly demonstrated
that the varietal testing requirement was inconsistent with the obligations set out in Article 2.2 of the
SPS Agreement. As an alternative justification of the measure, Japan briefly invoked Article 5.7 of
the Agreement, but failed to meet the criteria set out therein as the relevant scientific evidence was not
"insufficient" but simply did not exist. The lack of a specific risk assessment appeared to support the
impression that there had been no "objective assessment of risk" specifically in regard to varietal

166 Japan's first submission, paragraph 154.
167 Ibid.

testing. Moreover, the long period since the requirement of varietal testing had been applied should
have allowed Japan either to scientifically underpin or eliminate this testing requirement "within a
reasonable period of time".
5.36 In summary, on the basis of the two first submissions by the parties as well as Hungary's own
knowledge of the matter, it was Hungary's view that the Japanese authorities a priori assumed the
existence of "varietal differences" with regard to basic and processed agricultural products which then
supposedly justified the requirement of separate testing of products not considered to be the "same".
Hungary was not aware of any scientific basis fo r the "same-product" concept which seemed to be
contrary to Article 2.2. Furthermore, there was, in Hungary's view, no provision in the Agreement,
not even Article 5.7, that would allow WTO Members to introduce or maintain phytosanitary
measures on the basis of hypotheses, assumptions or assertions. Neither could any support for this
position be found in the report of the Appellate Body in EC – Hormones. Such interpretation would
prevent the SPS Agreement from fulfilling its basic role, that of ensuring that SPS measures were not
applied for reasons unrelated to the protection of sanitary and phytosanitary health. A contrary
interpretation would open the door for effectively misusing SPS measures as disguised restrictions on
trade.
5.37 Finally, Hungary noted in respect of control, inspection and approval procedures that
although there was no specific time period established in the SPS Agreement, Annex C paragraph 1(a)
required that "such procedures are undertaken and completed without undue delay". As had been
stated by the complaining party and borne out by Hungary's own experience, the testing and approval
process for a given variety took anywhere from 2 to 4 years to complete. This could hardly be
qualified as being a reasonable delay. The extremely long time involved in such procedures added up
to the unusually heavy burden countries wishing to export agricultural products had to shoulder when
trying to comply with SPS requirements applied by Japan. Hungary believed that the procedural
aspects of an SPS measure also deserved a high degree of attention when judging their conformity
with the SPS Agreement, as they themselves could act as a disguised restri ction of trade which was
prohibited under the Agreement.
VI. PANEL'S CONSULTATION WITH SCIENTIFIC EXPERTS
A. P
ANEL'S PROCEDURES
6.1 The Panel recalled that paragraph 2 of Article 11 of the SPS Agreement provided that:
"In a dispute under this Agreement involving scientific or technical issues, a panel
should seek advice from experts chosen by the panel in consultation with the parties to
the dispute. To this end, the panel may, when it deems it appropriate, establish an
advisory technical experts group, or consult the relevant international organizations, at
the request of either party to the dispute or on its own initiative."
6.2 Noting that this Panel involved scientific or technical issues, the Panel consulted with parties
regarding the need for expert advice. Neither party objected to the Panel's intention to seek advice
from individual experts. On 27 February 1998, the Panel informed the parties of its decision to seek
scientific and technical advice as foreseen in paragraphs 1 and 2, first sentence, of Article 13 of the
DSU, and pursuant to paragraph 2, first sentence, of Article 11 of the SPS Agreement. The following
is an excerpt from the Panel's decision in that regard
168:

168 The full decision (which also includes the timetable for the proceedings) is contained in a fax dated 27 February
1998, sent to both parties from the Panel.

Nature of advice
(a) On the basis of the first submissions from both parties, the Panel will determine the
areas in which it intends to seek expert advice.
Selection of experts and questions to experts
(a) The Panel will seek expert advice from individual experts.
(b) The number of experts the Panel will select will be determined in light of the number
of issues on which advice will be sought, as well as by how many of the different
issues each expert can provide expertise on.
(c) The Panel will solicit suggestions of possible experts from the Secretariat of the
International Plant Protection Convention (IPPC), and, subsequently, from the parties.
The parties should not contact the individuals suggested.
(d) The Panel does not intend to appoint experts who are nationals of any of the parties
involved in the dispute unless the parties ag ree with such appointment or in the event
the Panel considers that otherwise the need for specialized scientific expertise cannot
be fulfilled. Parties are, however, free to include in their delegations scientific
experts of their own nationality and may, of course, submit scientific evidence
produced by their own nationals.
(e) The Secretariat will seek brief CVs from the individuals suggested. To the extent
possible, these will be provided to the parties.
(f) The Panel will prepare specific questions for the experts. These will be provided to
the parties.
(g) The parties will have the opportunity to comment on and to make known any
compelling objections to any particular expert under consideration. At the same time,
the parties will have the opportunity to comment on the proposed questions, or
suggest additional ones, before the questions are sent to the experts.
(h) The Panel will inform the parties of the experts it has selected, and submit the
questions to the experts.
(i) The experts will be provided with all relevant parts of the parties' submissions on a
confidential basis.
(j) The experts will be requested to provide responses in writing; copies of these
responses will be provided to the parties. The parties will have the opportunity to
comment in writing on the responses from the experts.
Meeting with Experts
(a) Should the Panel decide it opportune, or should a party so request, a meeting with
experts, immediately prior to the second substantive meeting, may be held. Prior to
such a meeting, the Panel would ensure that: (i) the parties' comments on the experts'
responses would be provided to the experts; (ii) the experts would individually be
provided with their colleagues' (the other experts) responses to the Panel's questions.
6.3 The experts were invited to meet with the Pa nel and the parties to discuss their written
responses to the questions and to provide further information. A summary of the written responses
provided by the experts is presented below. The tr anscript of the meeting with the experts, held on
23 June 1998, is contained in Annex A of this report (Section 10).
6.4 The experts advising the Panel were:
(a) Dr. Neil Heather, Entomologist, University of Queensland, Corinda, Australia;

(b) Dr. Patrick Ducom, Fumigation Expert, Lormont, France; and,
(c) Mr. Robert Taylor, Fumigation Specialist, Natural Resources Institute, Chatham,
United Kingdom.
B. QUESTIONS TO THE EXPERTS AND THEIR COMPILED RESPONSES (SUMMARIZED)
Question 1: In relation to th e concepts: probit analysis, dose-mortality test, and confirmatory
test, could you: (i) state your understanding of these concepts; (ii) indicate the purpose of the
tests; (iii) comment on the validity of using dose mortality tests for comparing the efficacy of
quarantine treatment between varieties of the same commodity by calculating LD50 for each
variety; (iv) comment on the conf idence in predicting the level of mortality between varieties
and the relative efficacy of quarantine treatmen t when using, for the approval of an additional
variety, (1) only the procedure outlined in (iii); (2) the pr ocedure outlined in (iii) and
confirmatory tests; and (3) only confirmatory tests (to confirm the efficacy of the treatment
already imposed for a variety of the same commodity); and, (v) indicate, in respect of the
testing options outlined in (iv), how the type and quantity of the information derived from the
tests on different varieties of the same commodity may vary, and what the causes for such
variations may be.
6.5 In respect of the understanding of the concepts and the purpose of the tests, Dr. Ducom noted
that the dose-mortality test, analyzed by the probit method, was the key to all trials concerning a
living organism's response to a toxic. The test was widely used by scientists in efficacy studies on
pests. It was informative in respect to the sensitivity of a species to a toxic. According to Dr. Ducom,
the utilization of LD
50 in dose-mortality test to compare the efficacy of quarantine treatment posed
two problems:
(a) Japan had demanded that variety X be compared to a reference variety . However, it
was sometimes impossible to have two varieties at the same time in the same
physiological conditions if these had different ripening dates. This could lead to
abnormal differences in the behavior of gas;
(b) the tests did not render a reliable statistical analysis given the fact that the number of
insects and fruit in question was low and that the causes of variation, of whatever
nature, had a great influence on the results. The following were two examples based
on the Yokoyama nectarine trials, 1987.
169
- The "Summer Grand" variety had a LD 50 of 6.3g/m3 compared to 15 - 18 for
the other varieties tested, but the dose that killed 100 per cent of the insects
was 40g/m3, compared to 30 - 35 for the others.
- Yokoyama and Vail, 1997, re-tested the "Summer Grand" and another variety
tested in 1987 and found equivalent results in contradiction with those from
1987. 170
6.6 Dr. Ducom noted that in practice, the LD 50 test constituted a fairly unreliable method to
compare the efficacy of quarantine. Furthermore, Japan imposed a subsequent confirmatory test
which was long and costly.

169 Supra note 67. (US Exhibit 14)
170 Supra note 79. (US Exhibit 16)

6.7 The confirmatory tests, by using a sufficient number of insects, gave the statistical confidence
which permitted achieving the desired threshold of 99.9968 per cent mortality (probit 9). This test
obtained a sufficient degree of confidence, but it was also costly.
6.8 Dr. Ducom noted that while the dose-mortality test (LD
50) did not give any confidence in
respect of the varietal factor, it did give an indication of the relative sensitivity of the products tested.
However, these indications undoubtedly did not allow for the determination of the part played by the
variety itself in relation to the other factors which could have an influence on the test results, such as
fruit ripeness, annual climatic differences, etc. In th is respect, the confirmatory test gave absolutely
no indication of varietal differences, it either worked or it did not.
6.9 Dr. Heather noted that probit analysis was a biometrical technique for analysis of
experimental data in which the quantitative response of an organism, usually as mortality, was
subjected to regression analysis with respect to treatment dose, i.e., "dose-response" data.
Mathematical transformation of mortality to probability units termed "probits" assisted in conversion
of the normal distribution (curve) of the response data to a linear distribution to facilitate analysis.
Dose data was frequently, but not invariably, logarithmically transformed for the same purpose of
linearity. The outcomes of probit analysis were values such as LD (lethal dose), LC (lethal
concentration) or LT (lethal time) for a nominated proportion of the population i.e., 50 per cent or
99.99 per cent, together with nominated confidence or fiducial intervals i.e., 95 per cent.
171
6.10 The main purposes of probit analysis were:
(a) to define susceptibility of a population of target organisms to a treatment in terms of
LD, LC or LT values;
(b) subsequent comparisons of susceptibility of populations of target organisms;
(c) subsequent comparisons of varying response according to substrates, such as
commodities;
(d) subsequent comparisons of treatments; and,
(e) prediction of the dose required for a specific level of treatment efficacy.
Comparisons were the most appropriate use of probit analysis.
6.11 Dose-mortality (dose-response) testing was an experimental procedure in which the response
of an organism was estimated for a series of mortality-inducing doses of a specified treatment. It
pertained to a group of tests known generally as bioassays. Dr. Heather noted that individual dose-
mortality tests had to target a specific stage of an organism wherever possible as the susceptibility to a
treatment could vary between life stages. The more direct the effect of the treatment or toxin on the
target organism, in general, the more precise and reliable were the results.
6.12 The main purposes of dose-mortality testing were to produce data for analysis, possibly, but
not exclusively by probit analysis, for:
(a) determination of above-mentioned parameters categorising the response of an
organism;
(b) comparisons of efficacies of different treatments, organisms or substrates; and,
(c) prediction of a treatment dose to meet a required level of efficacy.

171 Dr. Heather referred to Steel, R.G.D. and Torrie, J.H., Principles and Procedures of Statistics with Special
Reference to theBiological Sciences, McGraw-Hill (1960) p.22.

6.13 The target organism test unit was usually a sub-sample of 20 to 50 individuals typically
replicated 3 times, at each dose level. For a satisfactory result, 5 or more dose levels were usually
required, evenly spaced between 0 and 100 per cent mortality. The dose variable could be
concentration or duration.
6.14 Confirmatory test was a term that had restricted usage in a quarantine sense. By contrast,
probit analysis and dose-mortality testing were widely used in pesticide science. A confirmatory test
as used by US researchers equated to a large-scale test as used by Japanese researchers. The concept
applied to a single dose response test on sufficient numbers of the target organism to ensure that a
required efficacy had been attained at a nominated statistical confidence level. Countries such as
Japan and New Zealand had customized this test by requiring a number of sub-samples of minimum
size. This had the practical advantage that it could then be used in an iterative way to establish the
minimum dose required to achieve a desired efficacy.
6.15 Validity: In principle, dose-mortality bioassays were a valid method to characterize the
responses of test organism populations for comparison of the efficacies of quarantine treatments
between varieties of the same commodity, if adequate precision could be achieved. Use of LD 50
values for this purpose would be acceptable where the more desirable whole response line comparison
was not valid. Since the LD
50 was effectively the mean response of the bioassay test population and
where confidence belts were narrowest, it was arguably the most robust point of comparison.
Nevertheless it had to be supported by other point-wise comparisons such as at the LD
95, making the
slopes of the lines more readily apparent. These LD (LC or LT) values would give more precise
definition of response if the population of the bioassay organism was relatively homogeneous in its
response to the treatment.
6.16 In respect of confidence, Dr. Heather noted that in practice, large-scale confirmatory testing
was usually the most practicable and reliable assurance that a treatment was effective.
6.17 Variance: Dr. Heather noted that in phytosanitary experimentation variance was intrinsic to
both commodity172 and organism. If variance was not evident it would be cause for concern. The
dose-responses of an organism to a quarantine treatment could be expected to be influenced by
unavoidable variation within each commodity sample whether it was based varietally or otherwise. A
test organism on the surface of a commodity would be relatively unaffected by interaction with the
commodity and hence less variable in response than one present internally. As the stage for most
codling moth tests was the egg, an external stage, it could be expected that its intrinsic susceptibility
to the fumigant would be the same or closely similar for each commodity, given that all other
conditions were the same.
6.18 For a fumigation, variance originating from a commodity would be expected to be mainly the
result of sorption although other causes were possible. The resultant decay of the concentration
affected the dose received by the target organism and warranted monitoring during the course of the
fumigation, which was normal practice.
6.19 Dr. Heather noted in addition that other causes of commodity variation included interaction of
the parent scion with rootstock and interstock, production locality, weather, site orientation, water
management, nutrition, pests and diseases and their treatments, fruit initiation including pollination,
orientation of fruit on trees, ripeness and maturity. This meant that where differences between
varieties were small, fruit to fruit variation could greatly exceed variety to variety variation. Such

172 Dr. Heather referred to Beverly,R.B., Latimer, J.K., and Smittle, D.A. in: “Postharvest Handling: a Systems
Approach” Shewfelt, R.L. and Prussia S.E. , eds. Academic Press Ch 4, pp.74-98. and Hoffman, P.J., and Smith, L.G., in:”
Postharvest Handling of Tropical Fruits” , eds Champ, B.R., Highley, E. and Johnson, G.I., ACIAR Proceedings No. 50,
pp261-268

variation was an inherent characteristic and was usually overcome by ensuring adequate robustness of
the treatment.
6.20 Mr. Taylor noted that probit analysis was the application of a statistical programme to data
obtained from dose-mortality tests. It permitted a straight line to be drawn between dosage and
mortality and from this critical dosages and mortality levels to be determined.
6.21 Dose-mortality tests were tests conducted at laboratory level in order to determine the quantity
of a toxicant, such as methyl bromide, required to cause a particular level of mortality of an examined
insect (i.e., 50 or 90 per cent of the population).
6.22 Confirmatory tests were conducted on a large- scale to confirm that the dose and exposure
period derived from smaller tests would provide the level of quarantine treatment required in the field.
The principal purpose of a confirmatory test was th at by using large numbers of insects, account was
taken of any natural variations that might occur within insect populations. This would include the
testing of individuals that were more tolerant to methyl bromide than the general population, and which
might not be present where much smaller numbers of insects were tested.
6.23 According to Mr. Taylor, LD 50 values were extremely useful in comparing the toxicity of
different chemicals and in the measurement of resist ance. However, these values were less useful in
investigations of much higher levels of toxic response such as were necessary in relation to quarantine
treatments, where LD values of 99 or 99.9 were sought.
Question 2: In Japan's first submission 173, it is stated that "experimental error, physical
condition of the fruit, sorption of the fumigant by packing material, and load of fruit in the
chamber are the factors which scientists should be responsible for controlling in dose-mortality
tests. Indeed, scientists who conducted these tests describe that test conditions were consciously
made equal". To what extent is it feasible, technically and scientifically, to control such factors?
Does the Japanese statement mean that differences in dose mortality tests for different varieties
cannot be attributed to any of these factors?
6.24 Dr. Ducom noted that although there were controllable factors such as the load of fruit in the
chamber, the temperature, the packing material, the geographic and annual climatic differences 174,
there were other factors that were impossible to control: the physical and physiological conditions of
the fruit, ripeness, the precise stage of the insects at the time of treatment, small experimental errors,
unexpected leaks in the chamber, etc. Those who carried out experiments were aware that the results
of tests varied from one to another without the researchers necessarily understanding why.
Nevertheless, if, hypothetically, all the factors mentioned above were identical, then the difference, if
one existed, could be attributed to variety.
6.25 Dr. Heather pointed out that "experimental error" in this context would be expected to
include small errors in measurement, equipment imperfections, ambient conditions and biological
response variation in test organism populations. It could be minimized and standardized from test to
test but would always be present to some degree.
6.26 Variation in "physical condition of the fruit" from test to test could be minimized but not
eliminated. Handling injury, range of ripeness and ma turity, and the need to have fruit in a condition
susceptible to infestation at levels required for experimentation all contributed to unavoidable
variation in the physical condition of the fruit. This could have some effect on sorption levels despite
best efforts to standardise it.

173 Japan's first submission, paragraph 93.
174 Dr. Ducom referred to Exhibit 1 attached to his answers to the Panel's questions "PD Exhibit 1".

6.27 "Sorption of the fumigant by packaging material" and the walls of the chamber could be
standardized by researchers but some variability would always remain.
6.28 "Load in the test chamber" could be standardized by the control of fruit size, weight and
number, but again small levels of variation would be unavoidable.
6.29 Any experimental result would have background variation. It was usual to standardize
procedures ("consciously made equal") as far as possible but always, some variation would remain.
Its presence could be taken as evidence of the integrity of the experimenters. Statistical analyses were
used to minimize the effects but it would not be possible to eliminate them totally. Dose-mortality
was a bioassay and as such was relatively imprecise compared to a physical measurement, even when
measuring the direct effect on an organism.
6.30 Mr. Taylor noted that the Japanese position appeared to be that all tests should be conducted
under such standardized conditions that any physical differences arising between tests, including those
of the fruit, should be accounted for in the experiment al procedure. Whilst it might be expected that
conditions such as temperature, atmospheric pressure, loading, and even the type and condition of
packing material could be controlled very accurately in test programmes, it was difficult to state with
exact and absolute confidence that none of these factors could ever affect the results of tests. For this
reason it would appear to be too dogmatic to stat e that differences in dose-mortality could not be
attributed to any of the physical factors.
Question 3: Some of the results derived from dose-mortality tests seem to indicate differences
for different varieties of the same commodity tested. The parties indicated that a number of
factors may explain these differences
175. Is it possible scientifically or technically to determine,
by statistical or other methods, the relevant impact of each of these specific factors? If so, with
what degree of scientific and/or statistical certa inty for each factor? In your expert view, can
one determine that varietal difference is one of th ese factors? On the basis of the results of the
dose-mortality tests presented by the parties to the Panel (if appropriate, for each of the
commodities tested), as an expert, is it possible to make such a determination?
6.31 Dr. Ducom claimed that it was impossible by a simple dose-mortality test to determine the
relevant impact of the factors playing a role in varietal differences, mainly because varieties ripened at
different times. This had been adequately explained by the United States. 176 The dose-mortality test
presented by the parties were designed to give information on insect sensitivity. The search for
possible causes of varietal variations could not be determined with precision by them, but only with a
specific research program.
6.32 Dr. Heather noted that variability of the test organism, the test equipment, the test conditions
and the test sample of fruit would all influence differences in LD50 values from one variety to another.
However, it was probable that in most of the experiments under discussion, the major source of
variability would be differential sorption by the commodity. Although statistical differences were
evident between some varietally based experiments, this did not provide an assurance that the origin
of the difference lay predominantly in varietal characteristics.
6.33 Whether it would be possible to statistically identify the magnitude of the varietally based
components required expert biometrical comment.
Question 4: In the US first submission177, it is stated that "the accepted international practice in
the area of pest quarantine treatment by virtually every other country in the world is to require

175 See, e.g., the US first submission, paragraphs 33, 41, 42, 50 and Japan's first submission, paragraphs 92-94.
176 Dr. Ducom referred to the US first submission, paragraph 41.
177 US first submission, paragraph 96.

testing by commodity, not by variety". To your knowledge, is it common practice for
governments to require variety-by-variety testing for high-risk quarantine pests? 178 H o w
common is the variety-by-variety testing requi rement compared to, for example, testing by
commodity?
6.34 Dr. Ducom stated that he had no knowledge of any variety-by-variety testing requirement for
quarantine except the Japanese requirements.
6.35 Dr. Heather noted that although the United States submission contended that international
practice was to test by commodity and not by variety, at least two countries, Japan and New Zealand
had, in the past, adopted the practice of limiting acceptance to varieties tested although their
prohibitions might be listed by commodity. 179 That the United States had maintained the general
policy of accepting the variety used for testing as fully representative of the commodity was
evidenced by their own proclaimed schedules.180
6.36 Although the term "international practice" was used, many countries that imported fruit did
not actively enforce phytosanitary barriers. It was thus difficult to generalize on the basis of past
policy. Before the SPS Agreement came into force, decisions made by countries importing
commodities subject to quarantine considerations would have been more influenced by government
policies, procedures and precedents.
6.37 Mr. Taylor noted that as far as he was aware, it was not common practice for governments to
require variety-by-variety testing, and it was more usual for testing to be undertaken on a commodity
basis.
Question 5: Considering the current Japanese varietal testin g guidelines, how long would it
technically take (1) to conduct these tests and (2) once these tests are conducted, to come to an
administrative decision on acceptability of a new variety of an already tested commodity?
6.38 Dr. Ducom noted that a varietal test according to the Japanese guidelines was a time-
consuming procedure. The exact amount of time it would take would differ greatly depending on
whether there was already any active research on the insect at issue. If a test site was permanently set
up for mass rearing, the preparation of the insect stages for the specific harvest date was not a major
problem. It would, however, demand a sufficient number of insects to take into account unavoidable
incidents. There were two series of tests to conduct that would necessitate a one-year interval because
there was only one harvest per year:
(a) the dose-mortality test which required two to three months (the treatment itself
having to be carried out during the harvest); and,
(b) the confirmatory test which was best conducted the following year (this test would
entail three more months of work).
6.39 In a case were no mass rearing had been previously set up, it would have to be established. It
would take at least 1 to 2 years to domesticate the codling moth.

178 The footnotes to paragraph 27 of Japan's first submission identify pests considered by Japan to fall within this
category.
179 Dr. Heather referred to Japan, Exhibit 24: New Zealand MAF Regulatory Authority Standard 155.02.03 (1994).
180 Dr. Heather referred to USDA APHIS Treatment Manual Section 2.15 and T101. (1992 or subsequent).

6.40 In respect of the administrative decision, in theory, the results of the confirmatory test were
immediate and authorization could be given soon thereafter. However, an additional year would be
reasonable. The whole process could take at least 3 to 4 years.
6.41 Dr. Heather noted that the answer to the question depended on whether a new pest and
commodity were involved, whether a research infrastructure already existed and whether the same or
a similar pest and commodity had been the subject of comparable research elsewhere.
6.42 A reasonable expectation for research and preparation of a submission where there was an
established rearing method for the pest would be between 2 to 3 seasons. After that, consideration by
Japanese experts could take up to 1 year or longer depending on their backlog of submissions.
Questions from the Japanese experts to be answered, possibility involving further research, could take
a further season or longer. After acceptance of a proposal, there would be a need for a (Japanese)
confirmatory trial which, depending on the availability of the commodity, might not be possible
before the next production season. Further time would be required for Japanese authorities to prepare
for a Public Hearing and subsequent regulatory amendment. Dr. Heather noted that for Australia, the
time for the above procedure would usually span over 3 to 7 years.
6.43 Mr. Taylor noted that the test would need to be conducted over more than one season and also
with fruit of varying maturity, so that a period of two years would be necessary. He maintained that it
ought to be possible to reach an administrative decision regarding acceptance of tests on a new variety
of a commodity already tested within a period of twelve months.
Question 6: In the submissions before the Panel, which documents do you consider to contain
the fullest statement of the scientific rationale - if any such rationale exists - behind Japan's
current varietal testing requirements in respect of apples, cherries, nectarines and walnuts? Is
such scientific rationale (if any) linked to the commodity which is examined, or does it apply
equally across the commodities?
6.44 Dr. Ducom noted that Japan's concern was reflected in the statement that, in a few cases, the
sensitivity of a given insect stage apparently differed according to the variety that it was on. Turning
this into a general principle amounted to a precautionary principle more than any scientific rationale.
Japan based its precautionary principle on the fact that too high sorption risked resulting in an
insufficient CxT value. According to Dr. Ducom, this argument was not without merit, but he
questioned why Japan did not then demand as a crit erion for approval the obtainment of a defined
CxT value, rather than the setting of initial fumigation conditions.
6.45 Dr. Heather noted that the rationale advanced by Japan for "varietal testing" was given in
section III.E of the first written submission of Japan and defended in II.A of their second written
submission. Japan therein identified sorption of the fumigant gas as the major reason for differences
in LD
50 and CxT parameters between varietal samples and attributed these to "physical and chemical
properties of the fruits, which are then attributable to varietal characters" (paragraph 4.111). In Dr.
Heather's view, neither parameter was ideal for showing that there were consistent realistic
differences in efficacy of a treatment between varieties of a commodity, yet no alternatives appeared
more practicable. The CxT product was an average of the fumigant concentrations measured over the
fumigation time and the true LD50 was modified by MB sorption by the commodity. Also, individual
LD value comparisons did not take into account the slope of the response line and hence did not
measure the overall or direct response of the insect population.
6.46 Essentially, the Japanese argument hinged on whether the differences in test samples that
affected these parameters were predominantly varietal characteristics and whether they were of
sufficient magnitude to realistically affect treatment efficacy. It was the Japanese view that they did
both and this was believed to be the basis of their rationale.

6.47 The Japanese preferred model first required dose-mortality testing of the pest stage and
commodity variety(s) to ensure that differences did not influence treatment efficacy. By using the
stage/variety combination, if any, for which the pest was most difficult to kill for the remainder of
testing, the greatest risk was deemed to be covered. On this basis subsequent testing of additional
varieties should only need to be comparative unless greater difficulty of kill of the pest was
demonstrated. The Japanese model acknowledged this but required a further confirmatory test, the
reason for which was not readily apparent.
6.48 It was theoretically correct that results of an experiment were only proven for that exact set of
conditions, but this overlooked the purpose of experiments, which was to provide guidance for wider
use. The major problem was to determine the extent to which differences were varietal in origin.
6.49 Mr. Taylor noted that the documents contained within the second written submission of Japan
contained the fullest statement of the scientific evidence behind Japan's contention that testing by variety
was necessary to establish the efficacy of quarantine treatments. The submission contained references
and data to show that differences in sorption and CxT value had been shown between different varieties
of cherries, nectarines and walnuts. No data were presented with reference to apple varieties.
Question 7: In respect of th e risk of entry, establishment or spread of codling moth due to
differences in varieties that could affect the effi cacy of the quarantine treatment, what are the
technical/scientific factors relevant in an assessment of risk? To what extent has Japan taken
these factors into account?
6.50 Dr. Ducom stated that he did not know risk assessment techniques adequately enough to
respond to this question.
6.51 Dr. Heather noted that risk of entry, establishment or spread of codling moth due to
differences in varieties that could affect the efficacy of the quarantine treatment would relate
predominantly to:
(a) interaction between physical or physiological characteristics of the commodity and
the fumigant resulting in higher sorption (fumigant inactivation) in one variety than
another, and
(b) higher susceptibility of the commodity to the pest for a range of reasons resulting in
consistently higher levels of infestation risk in one variety than another.
Japan had concentrated on the first, paying close attention to LD
50 and CxT values.
6.52 The practice of quarantine was one of risk management. A key criterion adopted by Japan for
quarantine treatments for otherwise prohibited commodities was that the treatment had to provide a
measure of protection equivalent to import prohibition. While import prohibition could effectively
exclude commercially traded commodities, it still had to deal with traveller-carried contraband, so in a
sense, exclusion of a pest was always less than absolute. Quality requirements normally ensured that
commercially traded fruit was essentially free of codling moth infestation even where a quarantine
disinfestation treatment was not obligatory.
6.53 A important factor was the low pre-treatment incidence of codling moth in commercially
marketable host commodities from the United States compared to near 100 per cent artificially
infested experimental material, i.e., walnuts less than 0.03 per cent; nectarines, less than 0.0003
per cent; cherries, less than 0.00007 per cent; and apples less than 0.00008 per cent as shown in
exhibits (these estimates needed to be considered in conjunction with their variance).
6.54 Mr. Taylor noted that in 1995, the FAO adopted new guidelines on pest risk assessment
(PRA), the purpose of which was to ensure that pest s were defined as quarantine pests on the basis of

scientific principles in order to prevent unfair restrictions on trade. In the case of codling moth, Japan,
in its first submission to the Panel (pages 9-15) reported on the PRA conducted in 1996, the assessment
being conducted together with that for other pests. The Japanese assessment concluded the following:
(a) Codling moth was not present in the country.
(b) Environmental conditions in Japan were such as to give a grade 'a' for the potential
for establishment of codling moth within Japan.
(c) In relation to the potential for the pest to spread within Japan, this was graded as 'b'
taking into account the insect's relatively low reproductive capacity.
(d) Economic consequences to Japan of the establishment of codling moth were assessed
to be of particular significance because host plants such as apples and cherries were
produced in great quantity. As a consequence, the PRA analysis resulted in an 'a'
grading.
6.55 In summarizing the assessment, Japan concluded that codling moth presented a very high risk
and an overall grade 'A' was given. It was noted that the analysis with respect to codling moth
incorporated all the guidelines for PRA (recommended and adopted by FAO).
6.56 It would appear that Japan did take into account all of the technical and scientific factors
necessary in making a proper risk assessment for the entry of codling moth.
Question 8: In the US first submission
181 it is stated that "[e]very article published on the
efficacy of methyl bromide and/or methyl bromid e and cold storage for disinfection of codling
moth has demonstrated that there are no differen ces among varieties that affects efficacy of a
quarantine treatment". Could you comment on th is? On the basis of the scientific evidence
before the Panel, to what degree does the mort ality of codling moth differ between varieties of
the same commodity, of either apples, cherries, nectarines or walnuts, when treated with methyl
bromide (MB) or MB and cold storage?
6.57 Dr. Ducom noted that the conclusions of authors who had published articles on the efficacy
of methyl bromide had always been that the differences in sensitivity that might exist among different
varieties was insignificant. The major argument was that the 20 per cent buffer was sufficient to
exceed the limit of a possible difference in varietal sensitivity. 182 Dr. Ducom noted that there was a
need for research on the factors which influenced sorption. Reported differences between varieties
were significant with traditional probit statistical methods (the LD50 values were different). However,
it was very difficult from that to derive any practical conclusions. A great part of the present problem
lay therein.
6.58 Dr. Heather noted that the US view, that there were no published differences among varieties
that affected efficacy, was true if the criterion used was large-scale test results. If the criterion used
was statistically significant differences between experimental samples of different varieties there were
differences as identified by Japan, but there was no certainty that they were attributable to unique
varietal characteristics. In subsequent research on additional varietal samples these differences were
too small to cause the efficacy of a treatment, based on varieties used in initial trials, to fail in further
testing. This was equally true for commodity-s pecific treatments with methyl bromide or methyl
bromide and cold storage, for apples, nectarines, cherries or walnuts. For each of these, the Japanese

181 US first submission, paragraph 83.
182 Dr. Ducom noted that the amelioration of statistical methods allowed for a reworking of the first results and
invalidated the hypothesis of a statistical difference despite th e large difference interpreted as significant with traditional
methods. (US Exhibit 15)

minimum efficacy test requirement of no survivors from tests on more than 30,000 insects had been
met (3 x >10,000).
6.59 The treatments for apples, cherries, nectarines and walnuts differed, in part because the
fumigations had to be done at different handling temperatures and this affected the toxicity of methyl
bromide to the insects. Also, for apples that were cold tolerant in storage, fumigation was
supplemented with cold storage treatment. The actual tolerance of codling moth eggs to methyl
bromide was unlikely to differ between these commodities. If all were fumigated at the same
temperature, the treatments could be expected to be much closer.
6.60 Japanese concerns were valid, that a low treatment based on dose-mortality testing followed
by large-scale trials on a single varietal batch could have resulted in a treatment that would fail on
other varieties. It would largely depend on the amount of the "buffer" increase in relation to the
difference between varietal samples. Each instan ce of a very low threshold of susceptibility in a
variety in one season’s experiments
183 was shown to be anomalous as testing progressed, but some
varieties were lower than others in both LD and CxT parameters.
Question 9: Can a difference in the "sorptio n" level of MB during MB fumigation between
different varieties of the same commodity affect the efficacy of the quarantine treatment? If so,
do such differences indicate differences in varietal characteristics or are they
partly/mostly/completely due to other variables? Could you list the factors which you consider
contribute to differences in sorption levels.
6.61 Dr. Ducom stated that sorption on cereal grains had been covered by Banks 1992, showing its
importance in the success or failure of fumigation184, but there was little understanding of the sorption
of methyl bromide on fresh fruits.
6.62 Sorption levels had a direct influence on the efficacy of a treatment, but this influence was not
usually measured directly. It was measured using the CxT value. If the sorption was too high, then the
resulting CxT value would be too low, and there was a risk of insufficient efficacy.
6.63 It was, however, possible to find several cases where the influence of sorption on the CxT
value was nonexistent: for example in Yokoyama 1994
185, the set of sorption values (sorption having
diverse origins: variety, annual climatic differences, packing material, but with the same concentration
of 48 g/m 3) was organized in ascending order 186; the corresponding CxT values were distributed at
random but within narrow limits. Generally, the inverse was found, this was the case related in
Question 3 by the Research Division of Yokohama Plant Protection Station, where the sorption - CxT
value relationship was linear.187
6.64 Dr. Ducom stated that to his knowledge, no complete study specific to fresh fruit had been
conducted in the United States on the variety-sorption relationship. This would have been a good way
to respond to the question in a precise manner or to model possible interactions. Intuitively, it was
conceivable that variety could be an intrinsic factor in sorption variation, as was the case, for example,

183 Supra note 67 (US Exhibit 14); 1992 New Zealand study on cherries for Sam cherries (US, Exhibit 4 and
Japan, Exhibit 21).
184 Dr. Ducom referred to PD Exhibit 2.
185 Dr. Ducom referred to US Exhibit 36.
186 Dr. Ducom referred to PD Exhibit 3.
187 Dr. Ducom referred to US Exhibit 13.

in a study of sorption in raisins. 188 This study was based on the partition coefficient of methyl
bromide between the gaseous phase (the only part of gas that is active on the insect) and the solid
phase, i.e. the fruit (the part of sorbed gas that is not utilizable by the insect.) This coefficient was
directly linked to sorption and allowed it to be mode led. The study showed that this coefficient could
vary considerably between varieties and thus influenced the efficacy of a given general "raisin" dose.
The varietal aspect could be the result of interactions like the physiological state of the fruit, its
ripeness, etc.
6.65 Dr. Ducom noted that there was a lack of precise studies on this subject. A priori, one could
cite almost anything, the size of the fruit, the natu re of the epidermis, the average sugar content, the
ripeness of the fruit, its physiological cond ition, the time between harvest and fumigation, etc.
However, in respect of the issue at hand, there was a case which merited study.
6.66 Dr. Heather noted that differences in sorption levels attributable to varietal characteristics,
together with differences in sorption levels attributable to other causes between batches of a
commodity, would cause gas concentrations to decay differentially and hence affect the efficacy of
fumigation against the pest. Sorption was an inherent characteristic of fumigation as a treatment
method. Factors contributing to differences in sorption levels justified detailed comment by an
expert in fumigation chemistry.
6.67 Mr. Taylor noted that difference in the level of so rption of methyl bromide between different
varieties of the same commodity could affect the efficacy of quarantine treatment if the level of sorption
of a particular variety was of sufficient magnitude to reduce the concentration of methyl bromide gas
below the level required to cause insect mortality. However, this would require significant differences
between varieties to cause this difference in the level of sorption. Three types of sorption of a fumigant
could occur: adsorption, absorption and chemisorption.
(a) Adsorption of a gas such as methyl bromide was a physical surface effect and
resulted from the attraction of molecules to the surface of a commodity being treated.
The larger the surface area the larger may be the adsorption effect. An example
would be the case where a commodity had a very rough and therefore greater surface
area compared to another with a much smoother surface. Adsorption would be
expected to be less in the latter, but the differences in the magnitude of adsorption
would probably be small and likely to be insufficient to affect the efficacy of
quarantine treatment.
(b) Absorption of methyl bromide was also a physical process, but here the chemical
entered into the commodity and was held in either solids or liquids. Methyl bromide
was absorbed particularly by oils and fats in which it dissolved and, in commodities
with a high oil or fat content such as nuts, application rates of methyl bromide were
very much affected by this factor. It had been shown that the level of absorption
could be affected by the commodity moisture content; the higher the moisture level
the higher the sorption.
(c) Chemisorption was a third type of sorption and, being chemical in nature, was an
irreversible reaction in which residues were left in the fumigated commodity. Methyl
bromide reacted in particular with proteins and amino acid groups in a reaction
known as methylation, which led to a splitting of the methyl bromide molecule and
resulted in inorganic bromide residues. The rate of chemical reactions increased with
increasing temperature and for this reason chemisorption took place more readily the
higher the temperature.

188 Dr. Ducom referred to PD Exhibit 4.

6.68 Mr. Taylor noted that both adsorption and absorption were reversible reactions and were
affected by the temperature, sorption being greater at lower temperatures. For this reason, methyl
bromide application rates had to be greater at lower temperatures.
6.69 Sorption of methyl bromide was of particul ar importance for durable commodities because
different types of commodities, depending on thei r chemical constituents, required more or less
fumigant to achieve the level of treatment required. Durable commodities could be conveniently placed
in groups according to the dosage rates required. These commodity groups were very much connected
with oil and fat content, although other facts such as fineness of the commodity which could affect the
rate of gas penetration were important and could even affect the length of exposure necessary for
effective treatment.
Question 10: The US states in its submission s to the Panel that "minor differences in CxT
values between varieties do not indicate differences in varieties of a single commodity"
189. They
also state that "CxT values differ for tests on the same variety as well as for tests of different
varieties"190. In respect of walnuts, the US stated in its first submission that "test to test
variation of one variety was as great as that found among all three tested varieties" 191. The US
arguments are further expanded in paragraphs 20-32 of their rebuttal submission. Japan states
that the "link between varietal differences and di vergent efficacy of the fumigation treatment
may manifest itself by way of the difference in the 'CxT' value" 192. Japan uses three empirical
cases in its first submission to support its point that there were statistically significant differences
in the CxT values between the tested variety sa mples (see paragraphs 80-87, first submission).
Japan further elaborates its arguments in paragrap hs 35-42 of its rebuttal submission. In light
of the above, (i) could you define CxT values and explain what they are an indication of; (ii)
could you explain "Tukey's multiple range test" and its relevance to this issue 193; (iii) have the
results of the referenced reports (in the context of CxT values) been accurately assessed in the
parties' submissions?; (iv) could you list those factors which might be the cause of variations of
CxT values between varieties; and, (v) to the extent that varietal differences is among the listed
factors, what kind of varietal differences are yo u referring to? could such differences affect the
efficacy of MB fumigation?
6.70 Dr. Ducom noted that the notion of the concentration times product, or here the CxT value,
was fundamental in fumigation. What killed the insect was not only the dose of gas introduced, but
the quantity of gas inhaled during the entire gas exposure period. The measurement of gas
concentrations throughout fumigation permitted the monitoring of the efficacy from the initial
condition over the evolution time. The CxT value depended on the gas concentration in the chamber,
which varied depending on the following factors:
(a) initial dose introduced into the chamber;
(b) the load, which could increase or decrease the free concentration of gas according to
the sorption of the commodity;
(c) the sorption of the commodity and of everything present in the chamber; and
(d) possible leaks.

189 US first submission, paragraph 50.
190 US rebuttal submission, title 1. on p.8.
191 US first submission, paragraph 50; reference is made to US Exhibit 17, pp. 149-154.
192 Japan's first submission, paragraph 78.
193 Japan's first submission, paragraph 84.

6.71 The CxT value was universal once the target stage and the treatment temperature were
defined. All the other factors mattered little, even the nature of the commodity, since they were
accounted for by the measurement of gas concentration. Dr. Ducom stated that in his opinion, this
notion had been criticized wrongly by the United States 194; it had been stated that the CxT value
varied according to the ripeness of the fruit, the geographic conditions, etc. In fact, the CxT value
was simply used backwards, because the trials were conducted according to the doses and not the CxT
value. If a study using CxT values was undertaken, it was possible to say that to obtain a given CxT
value, the initial necessary dose would vary according to the ripeness of the fruit, the geographic
conditions, etc. It had also been stated that the "CxT certainly is not indicative of any varietal
characteristics"; but this was, according to Dr. Ducom, not true.
195
6.72 Dr. Ducom reiterated that the CxT value could be specifically set and the parameters could
subsequently be manipulated. Contrary to this, present conditions to impose a recognized effective
treatment consisted in fixing initial intangible conditions (temperature, treatment length, gas tightness
of the chamber, nature of the packing material and load) that would make any variation impossible.
6.73 Dr. Ducom agreed that the confirmatory test constituted a necessary condition to define the
quarantine level for a given species of pest. It was furthermore possible to associate the test to a CxT
value, which was then acquired once and for all. This was the case, for example, proposed by
Yokoyama for nectarines (68 ±3gh/m
3).196 This objective CxT value could thus become the sole
criterion for success in quarantine treatment.
6.74 In respect of Tukey's multiple range test, Dr. Ducom noted that as he was not a statistician, he
could not give any precise opinion on the statistic quality of that test. However, as he understood it, it
was not relevant to the resolution of the problem. In the precise case of walnuts, the oil content, for
example was a factor of varietal selection. It was clear that under that case, there would be varietal
differences in sorption, and thus in the CxT values, because methyl bromide was very soluble in oils.
6.75 In respect of the referenced reports (in the context of CxT values in the parties' submissions),
Dr. Ducom noted that it seemed, in general, that the notion of CxT had not been studied enough and
that that was apparent in the submissions. Indeed, for the Japanese, this notion seemed primordial.
197
But even so, they did not make use of any American data with the notion of CxT and they continued
to demand the dose-mortality tests and confirmatory tests without any reference to CxT values. The
Americans had also shown to be illogical in the same way.198 Contrary to the Japanese, the American
officials minimized their interest in CxT values, whereas researchers made concrete propositions for
confirmatory tests.199 Dr. Ducom noted that he completely accepted the references presented by Japan
in response to Question 9 as set out in US Exhibit 3.200

194 Dr. Ducom referred to the US Oral statement of 2 April 1998, paragraph 38, third point.
195 Dr. Ducom referred to PD Exhibit 4, Table A3, p.248.
196 Dr. Ducom referred to US Exhibit 12 (supra note 76).
197 Dr. Ducom referred to Japans first submission, paragraph 79-86, 104 and 128.
198 Dr. Ducom referred to the second US submission, paragraph 28.
199 Yokoyama proposed a CxT of 68 gh/m 3 for the quarantine treatment of nectarines (Dr. Ducom referred to US
Exhibit 12; see also supra note 76).
200 Dr. Ducom referred to Japan's references to: Bell 1996; FAO 1983 and Bond 1984 in response to Question 9 as
set out in US Exhibit 3.

6.76 In respect of whether varietal difference could affect treatment efficacy, Dr. Ducom noted that
it was rarely possible to foresee the influence of a varietal factor on sorption, and thus on the CxT
value. Only experimentation and modeling using numerous examples could respond to this question.
However, a priori, it was difficult to see what significant influence a color or a different ripeness
could have on the behavior of gas. On the other hand, one could easily see that a different oil content
from one walnut variety to another would lead to a pronounced difference in the behavior of gas,
though not necessarily in the efficacy of treatment.
6.77 According to Dr. Heather , the CxT value for a fumigation was an expression of the
relationship between fumigant gas concentration and time in the fumigation enclosure or chamber. It
was generally expressed as CT= k but was more properly expressed as C
nT=k where n was a toxicity
index.201 As such, it was an expression of the active gas dosage to which the pest or test organism
was exposed during the time of the treatment. Because the concentration decayed during the
fumigation time from the causes already discussed, "concentration" was an average value derived
from a number of measurements and required temperature, load and humidity to be specified for
proper definition. It could be inferred from Bond that it would be more usual to manipulate fumigant
concentration and time to arrive at a required CxT value than to use CxT as a record of dose.
202 The
CxT relationship could be very complex. It was a field of expertise related to physical chemistry of
gases and should only be commented upon in detail by an expert in that discipline.
6.78 Dr. Heather stated that Tukey's multiple range test was best explained by an expert in
biometry.203 It compared results between experiments, in contrast to other commonly used tests of
significance which compared treatments within an experiment. As such it was said to be less
sensitive in the identification of significant differences.
6.79 Dr. Heather claimed that no inaccuracies were apparent in the assessment of referenced
reports with respect to CxT values by either Japan or the United States, which, understandably, used
specific findings to support their submissions.
6.80 The main factors in experimental variance would be expected to be:
(a) unavoidable experimental variation including those resulting from measurement,
equipment function, small temperature fluctuations and chamber load; and,
(b) sorption differences in commodity samples, including variety-linked differences if
any.
6.81 Dr. Heather noted that varietal differences of importance would be expected to be mainly
sorption related. Further clarification would lie in the spheres of expertise of fumigation chemistry
and plant physiology. Such differences would need to be large to affect the efficacy of fumigation
and should be apparent to experienced researchers and risk analysts. The consistent success of the
large-scale confirmatory tests under discussion indicated that no overall differences of this magnitude
occurred.

201 Dr. Heather referred to Winks, R.G., The Biological Efficacy of Fumigants: Time/Dose Response Phenomena,
in Pesticides and Humid Tropical Grain Storage Systems (eds B. R. Champ and E. Highley) ACIAR Proceedings No. 14
pp211-221 1986.
202 Dr. Heather referred to Bond, E.J., Manual of Fumigation for Insect Control . FAO Plant Production and
Protection Paper 54 (1984), pp.20-27. (Japan, Exhibit 12)
203 Dr. Heather referred to Steel, R.G.D. and Torrie, J.H., Principles and Procedures of Statistics with Special
Reference to the Biological Sciences Mc Graw-Hill Book Company (1960), p109.

Question 11: Japan states that varietal differen ces accounted for at least some of the observed
differences in CxT values between dose-mortality tests (and that CxT values are indicative of
treatment efficacy). Technically and scientifical ly, if additional varieties were tested only for
CxT values, and those values were within the range already observed for other varieties, to what
extent would any further efficacy testing of the variety be necessary?
6.82 Dr. Ducom stated that if varieties were tested to find the CxT value, then no further testing
was necessary. The success of the system required:
(a) that the trials be conducted according to precise guidelines approved by both parties
(in particular, the number of fruits should be quite large in each replicate to minimize
the effects of sampling); and,
(b) that the treatment standard clarify the Cx T value necessary to obtain the desired
efficacy. This value was the one found in the confirmatory test, for example for
nectarines, 68 gh/m3. 204
6.83 Dr. Ducom stressed that the results of these tests were sufficient in themselves to give
confidence in the conformity of the candidate variety without having to include the reference variety
and insects for efficacy confirmation. This would not bring any supplementary information.
Furthermore, research on the CxT value per variety was an operation which could be rapidly
conducted, since only the variety of fruit to be tested was used. Fumigation only lasted two hours and
the result was known immediately.
6.84 Dr. Heather stated that if the CxT value for a required efficacy against a pest was known
 then
a fumigation treatment that met or exceeded that specification could be expected to achieve the
quarantine security level required. This would hold true for all batches of a commodity, including
those of differing varieties, provided that temper ature, load and any other relevant requirements were
met.
6.85 Fumigation of agricultural commodities could be specified according to CxT requirements of
the pest or pest group with consideration given to levels of concentration which might be phytotoxic
to the host commodity. The requirement by the Unit ed States in its own gazetted treatments, that
specified concentration levels be met part way through the MB fumigations for some commodities,
appeared to be an example of this approach.
205
6.86 Mr. Taylor stated that CxT values were used to indicate the fumigant concentration and
exposure period required to achieve a 99 per cent mortality of all development stages of an insect, at a
particular temperature and humidity, under practical conditions. If these values were obtained for
additional varieties and were found to fall within the range already observed for other varieties, it would
be difficult to justify why further testing would be necessary.
Question 12: To the extent, if any, that ther e are varietal differences in apples, cherries,
nectarines or walnuts, which could affect the e fficacy of MB treatment, can these differences be
so high that they are not covered by the 10 -20 % "buffer" normally added to the highest
minimum dose (minimum dose for 100% mortality) derived from dose-mortality tests for one
variety of a given commodity? Is the "highest minimum dose" (to which this "buffer" is added)
calculated for each variety separately or, in case an application is made for several varieties, for
all these varieties taken together? Could you elaborate on any differences there might be
between the general practice and the procedures followed by Japan.

204 Dr. Ducom referred to US Exhibit 12 (supra note 76).
205 Dr. Heather referred to USDA APHIS PPQ Treatment Manual Section 2.15 and T101. (1992 or subsequent)

6.87 Dr. Ducom noted in respect of the calculation of the highest minimum dose that it was
always measured on one variety, never, to his knowledge, on a mixture of several varieties. This was
linked to the fact that generally a single variety was studied and not a mixture of several varieties, to
avoid the introduction of systematic heterogeneity.
6.88 The research procedure for quarantine treatment imposed by Japan corresponded to the
general guidelines accepted by all countries (research on the least sensitive stage that could be present
in fruit, confirmatory test), except concerning the varietal difference aspect. There were no variety-by-
variety trials elsewhere.
6.89 Dr. Heather noted that there was no evidence apparent from the experiments which formed
the basis for treatments for apples, cherries, nectarines and walnuts that the 10-20 per cent buffer
added to the experimental dose would be inadequate to cover differences of the magnitude shown
between varietal samples.
6.90 If only one variety had been represented in the initial testing, the possibility that other
varieties which might be proposed subsequently could have higher predicted minimum dose
requirements would be greater. Even so, the likelihood of this exceeding the 10-20 per cent "buffer"
appeared low. Also, it would almost certainly have been a matter of scientific rigour on the part of
researchers to ensure that the initial test fruit were as representative of commercial exports as
possible.
6.91 At the levels of efficacy concerned, the incidence of survivors due to varietal differences
would be very low. For a minimum efficacy of 99.99 per cent there would be less than 1 survivor
from 10,000 on average overall, so the actual effect of varietal differences on quarantine risk was
extremely small and difficult to evaluate.
6.92 Normally, the dose to which the 10-20 per cent buffer was added would have been estimated
from the varietal trial in which the LD
 values had been highest hence, "the highest minimum dose".
How this dose was chosen was a matter of subjective judgment, but if the minimum efficacy required
was 99.99 per cent the LD99.99 could be computed together with fiducial limits and either the LD value
or its higher fiducial limit used as the dose to which the 10-20 per cent was added. This tended to
over-estimate the dose required. Alternatively, the lowest experimental dose for which there were no
survivors (100 per cent mortality) in the varietal trial with the highest levels of survival could be used
as the minimum effective dose and the "buffer" of 10-20 per cent added.
6.93 The Japanese large-scale confirmatory test differed in size and procedure from some other
countries, including the United States, but these were matters of detail. It was in its varietal and
country-oriented procedural approach to conditional lifting of import prohibition that Japan differed
most from the United States and other countries.
6.94 Mr. Taylor noted that any varietal differences affecting the efficacy of MB treatment were
unlikely to be so great that the buffer of 10-20 per cent failed to account for these differences. Effective
quarantine treatment was therefore to be expected. It was not clear from the documentation submitted
whether the highest minimum dose to which the "buffer" was added was calculated for each variety or
separately for several varieties taken together.
Question 13: In the US first submission
206 it is stated that "confirmatory tests are the relevant
indicator of efficacy of quarantine treatment. Therefore this normal variability in testing
results [derived from dose-mortality tests] cannot constitute a legitimate basis for denying
approval for other varieties of the same commodities". Could you comment on this in relation
to codling moth treated with MB fumigation? Are confirmatory tests (using the treatment

206 US first submission, paragraph 56.

found to be effective for an original variety) sufficient to demonstrate efficacy of quarantine
treatment for additional varieties (e.g., to achieve a probit 9 mortality level)?
6.95 Dr. Ducom noted that a dose-mortality test did not replace a confirmatory test. But if one
accepted the postulate that whatever the dose-mortality test result was, it would not question the
standard already accepted, then what was the purpose of these dose-mortality tests?
6.96 Dr. Heather noted that the broader applicability of a confirmatory test done on samples of
one variety of a commodity depended on the extent of variation of mortality attributable to varietal
characteristics. For quarantine purposes, it was the effect of the treatment on the pest that was of
principal importance. A decision on whether to extend acceptance to all varieties of a commodity
from a country could be based on factors that included:
(a) past experience with other pests or other treatments on the commodity;
(b) legislative or procedural requirements of the importing country;
(c) the performance of the same or similar treatments in use by other countries for the
same or other varieties;
(d) the extent of differences between varieties; and,
(e) small or large-scale tests on a representative range of varieties.
6.97 A large-scale confirmatory test against a pest on a commodity was highly effective in
providing assurance that the treatment as tested wo uld meet an efficacy requirement. It provided
good assurance for the extension of an existing successful treatment to additional varieties of a
commodity, provided that the initial varietal sample was representative of the commodity. The target
efficacy had to be adequately specified. Probit 9 as a target efficacy level needed to have a specified
confidence level that enabled the required test sample size to be determined. It was better understood
when expressed as the percentage mortality to be achieved (99.9968%) and confidence level required.
Question 14: Considering the scientific evid ence before the Panel, would the MB treatment
approved by Japan for some varieties of apples, cherries, nectarines or walnuts mentioned in
US Exhibit 1, meet probit 9 protection for the varieties of each or any of these commodities
mentioned in US Exhibit 1 which have not yet been allowed for import into Japan?
6.98 Dr. Ducom answered that "yes", a positive confirmatory test constituted the best proof of
efficacy. All the species and varieties having passed this test positively would then satisfy all the
quarantine requirements.
6.99 Dr. Heather noted that where additional varieties of apples, nectarines, cherries and walnuts
had been subjected to a successful confirmatory test to meet probit 9 as defined by Japan, there would
not appear to be any technical quarantine reason why they would not be acceptable to Japan, subject
to their approval procedures. Some of the varieties of apples in question were being accepted by
Japan from New Zealand and would necessarily require a codling moth disinfestation treatment the
same as, or equivalent to, that developed by the United States for varieties already approved.
207
6.100 In the absence of a large-scale confirmatory test, it was not possible to be absolutely certain
that additional varietal samples would meet the standard required. Where it could reasonably be
expected that they would, this had to be the basis of the risk management decision.

207 Dr. Heather referred to Japan, Exhibit 8, attached table 24.

Question 15: Is it relevant to compare the varietal treatment of apples, nectarines, cherries and
walnuts to the differential treatment of other agricultural commodities? (e.g., thermal treatment
of mangoes where characteristics such as size and shape influence the treatment of the fruit)
208.
In respect of other agricultural commodities, can you give examples of actual cases where
concern over varietal differences has given rise to diverging phytosanitary requirements
between varieties of the same commodity?
6.101 Dr. Ducom stated that the reactions of a vegetable product to a gas compared to a physical
phenomenon such as temperature had, a priori, nothing to do with each other. In the first case, one
had to deal with the problems of sorption of a chemical or physico-chemical nature. In the second
case, it was a question of thermal conductivity. Dr. Ducom was not aware of cases where concern
over varietal differences had given rise to diverging phytosanitary requirements between varieties of
the same commodity.
6.102 Dr. Heather stated that the main relevance of the comparison of the US approach to hot
water treatment of mangoes and the Japanese approach to MB fumigation was the possible
modification of the treatment by the commodity before it acted on the pest. For mangoes, it was the
time taken for the centre of fruit to reach a temperature lethal to any internally feeding fruit fly larvae.
Because it was not practicable to use electronic temperature probes in hot water dips, a total time of
treatment needed to be specified according to size and shape of fruit, which was a varietal
characteristic but not exclusively so. Mangoes from Thailand for export to Japan were "vapour heat"
treated using differing schedules according to variety. Part of the reason for this related to perceived
varietal susceptibility to treatment injury.
6.103 Mr. Taylor stated that fumigation was a very special method of quarantine treatment and bore
little relationship to any other method of treatment. Of the factors affecting the efficacy of fumigation,
sorption could be considered to be particularly important, but size and shape of fruit were not factors
that could affect treatment efficacy such as by in fluencing the movement of the fumigant. Size and
shape of fruit could not be compared to the di fferences found between some durable commodities,
wheat flour for example being very different to whol e wheat grains, the former greatly restricting the
movement of methyl bromide because of the par ticle size. Mr. Taylor was not aware of other
commodities where concern over varietal differences had caused the need for diverging phytosanitary
requirements.
Question 16: Japan states in its second submission
209 that "it is true that existing treatment
levels of host plants of codling moth have been found effective for additional varieties.
However, as a matter of science, all this prov es is the efficacy of the treatment on the tested
varieties. It falls short of showing absence of varietal difference within a commodity altogether"
[emphasis added] 210. Japan also states that the United States cannot possibly provide any
information of products yet to be developed which "may utilize rapidly advancing
biotechnology"211. Yet, the United States considers that "testing by commodity is the only
acceptable quarantine measure in the context of this dispute" and that after the first variety of a
particular commodity has been tested accord ing to current Japanese procedures, "no further

208 Japan's first submission, paragraphs 108-113; US rebuttal submission 13-16; and, Japan's rebuttal submission
paragraph 25.
209 Japan's second submission, paragraphs 45-48.
210 Japan's second submission, paragraph 45.
211 Japan's second submission, paragraph 48.

testing is necessary for additional varieties"212. Is there a scientific basis for either of the parties
views set out above?
6.104 Dr. Ducom stated that the arguments put forth by Japan for requiring varietal trials were not
based on scientific data. They were supported by a few experimental data in which varietal difference
existed, in terms of LD 50, among plenty of other data in which they did not. These observations had
led Japan to suspect all existing varieties, as well as those of the future (where, in Japan's view,
genetic engineering and biotechnology could create even greater differences). This was not based on
any scientific data.
6.105 The arguments put forth by the United States were based on a large number of experiments,
of which Japan had thoroughly made use. Varietal difference appeared several times, but each time
the confirmatory test had revealed sufficient efficacy. Extrapolation to all available varieties was no
more scientific than Japan's contrary assertion. This sort of extrapolation was something along the
order of intuition. It was unfortunate that there had not been a research program on the subject in
order to try to present some scientific proof.
6.106 Dr. Heather stated that the Japanese view on applicability of experimental results was
technically correct but, in practice, the purpose of experimentation was to provide guidance for
decisions on a broader basis. There was a strong case for flow-on where varietal differences were
unlikely to impinge on fumigation efficacy. However, most countries would reserve their right to
make exceptions if they foresaw a risk that efficacy might be compromised by varietal or other
differences. The problem was more one of risk management as the scientifically definable differences
would normally be small and difficult to determine due to variability.
6.107 Specification of a treatment as a CxT value for the pest instead of an initial fumigant amount
and time could overcome this problem, but would require a level of monitoring which would need to
be practicable. The United States used this approach to varying degrees in its methyl bromide
quarantine treatments as mentioned in paragraph 6.85 above.
Question 17: Could you describe the nature of the varietal differences between the varieties of
the commodities listed in US Exhibit 1 (e.g., colo ur, taste, shape). Could the nature of these
differences affect the efficacy of MB treatment?
6.108 Dr. Heather noted "Granny Smith" and "Delicious" apples differed in colour, shape, flavour
and time of maturity. Dr. Heather was not aware of any major differences in susceptibility to codling
moth other than those possibly phenology based. As confirmed by US large-scale trials, the required
efficacy had been achieved for both of these varieties and, given the combined lethal potential and
broad applicability of methyl bromide and cold trea tment, it was highly unlikely that there would be
any differences in efficacy between any common commercial apple varieties. One problem that might
occur was susceptibility of some varieties to treatment injury.
Question 18: Is it scientifically correct to say that "peach" includes "nectarines"?
6.109 Dr. Ducom affirmed that "peach" indeed was the ge neral term that referred to the species
Prunus persica. The notion of species was well cl arified; two individuals belonged to the same
species if they were able to exchange genes to produce viable offspring. The peach species had
undergone natural mutations. Some mutations concerned the shape; the flat peach variety, platicarpa.
Another, of relevance to the question, caused the peach to shed its epidermal fuzz: this was the
variety nucipersica, the nectarine.

212 US answer to the Panel's Question No. 4 (addressed to the United States), 21 April 1998.

6.110 Dr. Heather noted that Willis gave the systematic botanical (species) classification of peach
as Prunus persica and categorized nectarine as a variety of peach. 213 The US submission gave sub-
species status to nectarine as P. p. nucipersica.214 Taxonomic status at this level tended to be
subjective. Classification as a sub-species implied stable characteristics which could be recognized
for descriptive purposes. If the species defined the commodity, nectarine would be a variety of peach.
6.111 Mr. Taylor affirmed that it was scientifically correct to say that "peach" included "nectarines"
because a nectarine was a smooth-skinned mutant of peach. It was botanically classified as a variety of
peach Prunus persica, nucipersica.
C. ADDITIONAL WRITTEN QUESTIONS SENT TO THE EXPERTS ADVISING THE PANEL
1. Additional question on walnuts
6.112 On 25 June 1998, the Panel sent the following additional question to the experts advising the
Panel:
"At the second substantive meeting of the Panel, on 24 June 1998, the United States
submitted the attached publication (US Exhibit 40215) with a cover letter by its author.
The Panel would kindly ask for your views on the following:
On the basis of this publication, could you express your view on:
(a) whether and to what extent the oil or fat content differs between varieties of
walnuts because of varietal characteristics; and.
(b) whether any such differences are significant enough to affect quarantine
efficacy."
6.113 Dr. Heather noted that his interpretation of the paper by L. Carl Greve et al ., was that it
examined the genotype – environment relationships affecting the percentage of polyunsaturated fatty
acids in oil of walnuts. Dr. Heather did not find any information on total oil content as a varietal
characteristic. Therefore, the paper, in his view, did not provide any further clarification on the extent
to which the oil content of walnuts could affect quarantine treatment efficacy and, consequently,
quarantine security. The paper did, however, provid e additional insight into the complexity of the
relationship between inherent varietal characteristics and the environment.
6.114 Dr. Ducom noted that differences between varieties in walnut commodities, if any, could
easily be shown by way of the oil content. Methyl Bromide was soluble in oil or fat and the decrease
in gas concentration in the fumigation chamber resulting from this sorption was measurable in
sorption trials. If one variety had a difference in oil content large enough to modify the sorption
pattern and consequently the CxT value, then the efficacy of the quarantine treatment could be
affected. On the basis of the publication in question (US Exhibit 40), variety was one of the different
factors which could affect the oil content of the fruits. However, the authors had shown that its

213 Dr. Heather referred to Willis, A Dictionary of the Flowering Plants and Ferns, Cambridge University Press,
(1960).
214 Dr. Heather referred to US Exhibit 15, p.2.
215 Variation in Polyunsaturated Fatty Acids Composition of Persian Walnut, L. Carl Greve, et. al., J. Amer. Soc.
Hort. Sci. 117 (3), pp. 518-522, 1992.

influence was less important than the environmental conditions (location, light, irrigation, etc.). In
Dr. Ducom's view, differences such as those presented in the publication appeared not to be large
enough to have any noticeable influence on the sorption and thus the CxT value and efficacy. Only
trials designed for the purpose of answering that specific question could give an adequate response.
6.115 Mr. Taylor noted that he agreed with the conclusions of L Carl Greve that environment,
genotype, nut maturity and interaction of these factors appeared to be the most important parameters
determining the fatty acid content in walnuts. The greater differences in fatty acid content
composition found from year to year within the same variety than between varieties in a single year
was also very important evidence demonstrating that varietal differences were unlikely to be the most
important factor affecting sorption of methyl bromide and, therefore, the efficacy of methyl bromide
fumigations.
2. Confirmation of the Panel's understanding of scientific evidence and opinions
6.116 On 28 July 1998, the Panel sent 10 pages of its draft findings (in this report: paragraphs 8.73
to 8.101) to the experts advising the Panel to confirm that the scientific evidence referred to therein
had been correctly reflected and, in particular, to ascertain that the references to the experts' opinions
had – from a technical and scientific point of view – been accurately reflected. The answers by the
experts (summarized in the following three paragraphs), together with the Panel's draft findings as
sent to the experts, were provided to the Parties at the time the Panel submitted its interim report to
the Parties.
6.117 Dr. Heather stated that the Panel's interpretation of his submissions had been correct with one
exception. This exception was with respect to the use of the term probit 9. In the view of Dr.
Heather, if the term probit 9 – or any other probit value, or their equivalent mortality percentages –
were used in a definitive sense, it was important to give them in conjunction with a confidence (or
precision) level. Thus, in order to avoid the need to specify the precision of the probit 9 level of
protection, Dr Heather suggested that that level of protection was better stated as "no survivors from
tests on a minimum of 30,000 individuals", instead of stating that Japan's level of protection was
"probit 9", or "99.9969 per cent mortality".
6.118 Dr. Ducom noted, in general, that the Panel had understood what had been explained and that
the text was logical. In particular, Dr. Ducom drew the Panel's attention to the fact that the two
treatments for apples (cold treatment and MB fumigation) were independent from one another. While
the cold treatment killed the egg stage of codling moth, the MB fumigation killed the fifth larval stage
(5
th instar).216 In his view, the sorption problems were the same for apples as for other fruits but did
not affect the efficacy of cold treatment.
6.119 Mr. Taylor stated that the draft findings accurately reflected his scientific and technical
opinion.

216 See paragraph 2.2 for the codling moth larval stages.

VII. INTERIM REVIEW217
7.1 On 1 September 1998, the United States and Japan requested the Panel to review, in
accordance with Article 15.2 of the DSU, precise aspects of the interim report that had been issued to
them on 6 August 1998. Japan also requested the Panel to hold a further meeting with the parties on
the issues identified in its comments on the interim report. We met, accordingly, with the parties on
21 September 1998.
A. COMMENTS BY THE UNITED STATES
7.2 Following comments from the United States we redrafted paragraphs 8.77, 8.93 and 8.96 in
order to clarify that, according to the experts advising the Panel, varietal differences – and the
resulting difference in sorption levels between varieties – need to be significant to affect the efficacy
of the already approved MB treatment.
7.3 With respect to paragraphs 8.82 and 8.99, the United States reiterated its view that – although
no disagreement exists as to the level of mortality Japan requires – Japan never defined its appropriate
level of protection. We redrafted these paragraphs to take account of this point of view. We also
noted Japan's view that its level of protection is that achieved by the import prohibition and that the
level of mortality it requires for lifting the import prohibition is one of the technical requirements to
ensure efficacy of an alternative measure.
7.4 As a result of a US comment, we added paragraph 8.102 in order to make clear that our
findings under Article 5.6 would stand even if the measure in dispute were not in violation of
Article 2.2. Doing so, we agree with Japan that our finding under Article 5.6 is not an alternative
finding stricto sensu, in the sense that it only stands if we would have decided that Article 2.2 is not
violated. What we wanted to clarify is that our Article 5.6 finding stands irrespective of our finding
under Article 2.2.
7.5 As a result of other comments from the United States, we also slightly redrafted certain other
paragraphs of the findings section of our report.
B. C
OMMENTS BY JAPAN
7.6 Japan, in turn, provided editorial suggestions to the descriptive part. Where the additions
requested had been referred to earlier during the proceedings, we incorporated them in the final report.
7.7 As a result of comments by Japan, a question arose as to the product scope of our finding in
paragraph 8.42. Japan submitted that nowhere in the report did it find a prima facie case of an
Article 2.2 violation established by the United States for the products other than apples, cherries,
nectarines and walnuts. Japan argued that the United States did not submit any evidence in respect of
these other products and that the Panel made an error in substituting the absent evidence, which
parties must submit, with the experts' answer to a Panel question. On that ground, Japan requested us
to exclude products other than apples, cherries, nectarines and walnuts from the scope of our
Article 2.2 finding in paragraph 8.42. The United States responded that for the other four products in
dispute (apricots, pears, plums and quince), th e presumption of an Article 2.2 violation was

217 According to Article 15.3 of the DSU, "the findings of the final report shall include a discussion of the
arguments made at the interim review stage". The following section entitled "Interim Review" is therefore part of the
findings of our report.

established as a result of the fact that Japan did not submit any scientific evidence for these products.
According to the United States, the SPS Agreement makes it clear that the burden has never been on it
to present scientific evidence that varietal testing is not required. Instead, the United States argued,
Japan has an obligation under Article 2.2 to base its varietal testing requirement for all products
covered by this case on sufficient scientific evidence.
7.8 In paragraphs 8.44 and 8.45 we specify that the scope of our finding that Japan maintains the
varietal testing requirement without sufficient scientific evidence extends to four of the eight products
at issue (apples, cherries, nectarines and walnuts). When addressing the product coverage of our
report, we have distinguished two issues. First, the product coverage of our terms of reference . In
paragraph 8.6 we find that the Panel was given the task to examine the measure in dispute as it applies
to eight products. This is not what Japan contested in its comments on the interim report. Second, the
product coverage of our finding that Japan maintains the varietal testing requirement without
sufficient scientific evidence. This is the issue raised by Japan in its comments on the interim report
and dealt with in paragraphs 8.44 and 8.45.
7.9 In our view, Japan is correct when it states that it is for the United States to establish a
presumption that there is not sufficient scientific evidence in support of the measure in dispute. It is
also true, in our opinion, that the United States has to do so for each of the eight products which fall
within our terms of reference. However, we do not agree that, in assessing whether such presumption
was established, we cannot take into account both the evidence submitted by the United States and the
opinions we received from the experts in accordance with Article 13 of the DSU.
218
7.10 In our view, the prima facie case to be established in a WTO dispute settlement proceeding
relates to the substantive issue of what a party invoking a fact or claim needs to prove for that fact or
claim to be accepted by a panel; that is, evidence (1) which is sufficient to raise a presumption that the
alleged fact or claim is correct and (2) that has not been sufficiently rebutted by the opposing party.
In deciding whether a fact or claim can thus be accepted, we consider that we are called upon to
examine and weigh all the evidence validly submitted to us, including the opinions we received from
the experts advising the Panel in accordance with Article 13 of the DSU.
7.11 With respect to paragraphs 8.38 and 8.39, Japan submitted that the only evidence in support
of the Panel's reasoning is a quote from Dr. Heather with respect to only one study before the Panel.
We recall, however, that a whole series of other evidence is referred to in paragraph 8.40 and
footnotes 273 to 276.
7.12 In response to Japan's comment that there is no support for the statement in paragraph 8.42
that "not a single instance has occurred … where the treatment approved for one variety of a product
has had to be modified to ensure an effective treatment for another variety of the same product", we
clarified and expanded this paragraph. In so doing , we also addressed Japan's claim that the United
States did not submit a prima facie case.
7.13 Following a comment by Japan on paragraph 8.46, relating to the quarantine efficacy of the
treatment required for apples, we also redrafted that paragraph. We further modified paragraph 8.84
to avoid the possible US misunderstanding that our finding in paragraph 8.84 does not apply to
apples.
7.14 With respect to paragraph 8.84, Japan requested the Panel to find that the United States did
not establish a prima facie case that testing by product would meet Japan's level of protection. In
reply we specify in that paragraph that the finding we make is arrived at after a careful examination
and weighing of all the evidence before us.

218 Article 13 of the DSU provides, in its first paragraph: "Each panel shall have the right to seek information and
technical advice from any individual or body which it deems appropriate"; and, in its second paragraph: "Panels may seek
information from any relevant source and may consult experts to obtain their opinion on certain aspects of the matter".

7.15 Japan's comments on other parts of our findings also prompted us to slightly redraft certain
other paragraphs of our findings.
VIII. FINDINGS
A. CLAIMS OF THE PARTIES
8.1 The United States challenges the way Japan lifts its import ban on products that may carry the
pest known as codling moth. Japan requires testing and demonstration of quarantine efficacy for each
variety of a product that may carry codling moth. Only once this is done will the import ban be lifted
and this only for the particular variety or varieties tested. Hereafter we refer to the contested measure
as Japan's "varietal testing requirement". The United States claims that this measure is inconsistent
with Articles 2, 5, 7 and 8 of the SPS Agreement. Japan requests the Panel to find that its measure is
fully consistent with the SPS Agreement.
B. J
APAN'S PLANT PROTECTION REGIME
8.2 On 4 May 1950, Japan enacted the Plant Protection Law. Article 7 (paragraph 1, item 1) of
that Law provides that plants designated by Ministerial Ordinance, which have been shipped from or
passed through districts designated by that Ordinance, are prohibited for import into Japan. By
Ministerial Ordinance of 30 June 1950 (Plant Protection Law Enforcement Regulations) eight
products originating from, inter alia, the United States (excluding the Hawaiian Islands) were listed as
prohibited plants. These products are: apricot, cherry, plum, pear, quince, peach, apple and walnuts,
imported as fresh fruit.
219 They are prohibited for importation on the ground that they are potential
hosts of codling moth. The Ministerial Ordina nce of 30 June 1950 also lists other products as
prohibited for import because they are hosts of other pests. However, there is a possibility to obtain
exemptions from the import ban. Such exemptions are granted on a variety-by-variety basis. Since
1969 a series of varieties of certain products, originating from specific areas, have been exempted
from the import ban. Moreover, since 1978 the import ban has been lifted for certain varieties of the
US products at issue.
8.3 In order to obtain an exemption from the import prohibition, Japan imposes the following
procedure. The exporting country has to propose an alternative measure which would achieve a level
of protection which is equivalent to that met by the import prohibition. The exporting country bears
the burden of proving that the proposed alternativ e would reach the appropriate level of protection.
Japan submits that this procedure is a "fundamental policy orientation". It has not been published as a
document. In practice, the alternative measure proposed is disinfestation. With respect to hosts of
codling moth, disinfestation consists of fumigation with methyl bromide ("MB") or a combination of
MB fumigation and cold storage (as required in the treatment approved by Japan for apples). As a
model test procedure for confirmation of the efficacy of this quarantine treatment, the Ministry of
Agriculture, Forestry and Fisheries of Japan ("MAFF") developed two guidelines: (1) the
"Experimental Guideline for Lifting Import Ban – Fumigation" and (2) the "Experimental Guide for
Cultivar Comparison Test on Insect Mortality – Fumigation". These guidelines were introduced in
1987 and have, according to Japan, not "generally been published". They are summarized in
paragraphs 2.23 - 2.24 of this report.

219 With respect to walnuts, the ban also applies to walnuts in the shell.

C. THE PANEL'S PRELIMINARY RULING OF 2 APRIL 1998
8.4 At our first substantive meeting we made the following preliminary ruling at the request of
Japan:
"Having carefully reviewed the written submissions made by the parties on the
preliminary issues before us and having heard the oral arguments made by Japan in
this respect, we rule as follows.
(i) We first examine Japan's request to exclude Article 7 of the SPS Agreement
from our examination on the grounds that it was only mentioned for the first
time in the US panel request (document WT/DS76/2) and that no
consultations were held on it. We note that our terms of reference (set out in
document WT/DS76/3) direct us to examine the matter before us "in the light
of the relevant provisions of the covered agreements cited by the United
States in document WT/DS76/2". This document, the US panel request,
specifically cites Article 7 of the SPS Agreement. We thus consider that
claims under that provision fall within our terms of reference.
(ii) We next address Japan's request for a finding that the phrase "including but
not limited to", mentioned in the US panel request, does not constitute part of
our terms of reference. We note that the United States, in its first submission,
did not make any claim with respect to a provision not specifically mentioned
in the US request for this Panel. Japan did not contest this. Consequently,
there is no claim before us (other than the one under Article 7 of the SPS
Agreement we just dealt with) on which to make a ruling of whether or not it
falls within our terms of reference.
(iii) Thirdly, as to the Japanese measures in dispute, we note that the United
States, in its first submission at paragraph 74, limited these to "the prohibition
by Japan on the importation of any variety of an agricultural product on which
Japan claims that the pest codling moth may occur until such time as the
variety has been separately tested with respect to the efficacy of treatment
with methyl bromide or treatment with methyl bromide and cold storage".
We regard this statement as setting the factual parameters of this case. It
limits the scope of this dispute to (1) agricultural products on which Japan
claims that the pest codling moth may occur (in its oral statement Japan stated
that there are eight such products: apricot, plum, pear, quince, apple, walnut,
peach including nectarine, and cherry; in its first submission, the United States
only addressed four products: apples, cherries, nectarines and walnuts) and (2)
varietal testing with respect to the efficacy of treatment with methyl bromide
or treatment with methyl bromide and cold storage".
D.
THE SCOPE OF THE MEASURE IN DISPUTE
8.5 The measure at issue in this dispute is only one element of Japan's plant protection regime.
The scope of this measure is limited in several respects.220
8.6 Firstly, only the varietal testing requirement imposed by Japan for lifting the import
prohibition on US products on which Japan claims that codling moth may occur is in dispute. The

220 See our preliminary ruling at point (iii), quoted in paragraph 8.4.

request for this Panel, which sets out the scope of our mandate 221, does not further limit the product
coverage of the Japanese measure challenged to certain specific products only. At our first
substantive meeting, Japan stated that it considers the following US products to be hosts of codling
moth: apricots, cherries, plums, pears, quinces, peaches (including nectarines
222), apples and walnuts.
We consider, therefore, that we are called upon to examine the measure before us as it applies to all
products covered by the contested measure. However, as we already noted in our preliminary
ruling223, the parties only submitted evidence with respect to apples, cherries, nectarines and walnuts.
We shall, therefore, examine the measure at issue on the basis of that evidence and refer to the experts
advising the Panel when it comes to evaluating th e relevance of that evidence for the other products
covered by the measure in dispute.
8.7 Secondly, we only need to examine Japan's varietal testing requirement to the extent it applies
to the demonstration of efficacy of MB treatment or of MB treatment combined with cold storage as a
treatment against codling moth. We are not called upon to address the varietal testing requirement as
it applies to any other treatment or any other pest.
E. MATTERS NOT IN DISPUTE
8.8 It is important to note what this dispute is not about. The United States does not contest that
codling moth is a serious pest of quarantine significance. Nor is it in dispute that codling moth is
exotic to Japan (i.e., is not found in Japan); that it does occur in the United States; and that the
importation of US fruit infected with codling moth could result in the introduction of codling moth in
Japan which, in turn, would have serious consequences for Japan's agricultural and forestry
production. The legitimacy and need for Japan to protect its plants against codling moth is not at
issue.224
8.9 Moreover, the United States does not challenge the original import prohibition imposed on
US host plants of codling moth. The United States acknowledges that Japan conducted a risk
assessment to determine that codling moth is a pe st of quarantine significance for which an original
import prohibition might be justified.
225 The United States refers rather to the possibility of obtaining
exemptions from this import prohibition and co ntests the conditions imposed for lifting this
prohibition, in particular the fact that it is lifted variety-by-variety.
8.10 Even with respect to the conditions for liftin g the ban, the United States agrees that, as a
general proposition, it is reasonable for Japan to require that the exporting country propose and
substantiate the efficacy of an alternative approach or a treatment that achieves Japan's level of
phytosanitary protection. Following that line of reasoning, the United States does not contest the
testing requirements imposed by Japan for approval of imports of the initial variety of a particular

221 Our terms of reference are, in accordance with Article 7.1 of the DSU, defined in document WT/DS76/3 and
specify that the matter we need to examine is the one referred to in document WT/DS76/2, i.e., the request for the
establishment of this Panel.
222 According to the experts advising the Panel, it is scientifically correct to say that peach includes nectarine (see
their answers to Panel question 18, paragraphs 6.109 - 6.111).
223 See our preliminary ruling at point (iii), quoted in paragraph 8.4.
224 See, for example, the expert opinions of Dr. Heather and Mr. Taylor, Transcript, paragraphs 10.204 - 10.210.
225 However, in so acknowledging, the United States did no t take a position as to whether this risk assessment
complies with the requirements in the S PS Agreement, arguing that this risk assessment does not relate to the matter in
dispute. Nor did the United States state that this risk assessment does justify the import ban in accordance with the SPS
Agreement. See also the expert opinions referred to in footnote 224 and Dr. Heather and Mr. Taylor's answers to question 7
of the Panel, summarized at paragraphs 6.51 to 6.56.

product, i.e., those contained in the "Experimental Guideline for Lifting Import Ban – Fumigation".
The United States contends, however, that after such validation no further testing is necessary for
additional varieties. It, therefore, challenges not only the content but the very existence of any
guidelines imposed for approval of additional varieties, in casu, those contained in the "Experimental
Guide for Cultivar Comparison Test on Insect Mortality – Fumigation".
8.11 We further note that there is no disagreement as to the efficacy of the treatment applied to the
specific varieties of US apples, cherries, nectarines and walnuts which have so far been exempted
from the import prohibition. The United States does not dispute the level of mortality, established by
Japan, that any quarantine treatment has to achieve (i.e., complete mortality in large-scale tests on a
minimum of 30,000 codling moths
226), nor does the United States, or Japan, contest that this level of
mortality is reached for the varieties already approved for import after they have been treated as
required.
8.12 Japan does not contest that the measure at issue is a phytosanitary measure covered by the
SPS Agreement, invoked by the United States. Referring to Article 1.1 and paragraph 1 of Annex A
of the SPS Agreement
227, we agree with the parties that the SPS Agreement applies to the measure at
issue.
8.13 Finally, with respect to the question of burden of proof under the SPS Agreement, we note that
both parties refer to the Appellate Body Report on EC – Measures Affecting Meat and Meat Products
(Hormones) (hereafter referred to as " EC – Hormones").228 Reviewing this report, we agree with the
parties that, in this dispute, it is for the United States to establish a prima facie case of inconsistency of
the Japanese measure at issue with each of the provisions of the SPS Agreement the United States
invokes. Once this is done, it is for Japan to counter or refute the claimed inconsistency. In other words,
if "[the United States] adduces sufficient evidence to raise a presumption that what is claimed is true, the
burden then shifts to [Japan], who will fail unless it adduces sufficient evidence to rebut the
presumption".229 In response to a Japanese comment on the interim report, we stress that the issue of
burden of proof in a WTO dispute settlement pro ceeding set out above is different and should be
distinguished from what a Member requires from an exporting country before it will approve the import
of that country's products. The latter issue is dealt with in paragraphs 8.10 and 8.30.

226 See paragraph 2.23 under "Large-Scale mortality test". See also answer by Dr. Heather summarized in
paragraph 6.117.
227 Article 1.1 of the SPS Agreement provides that the Ag reement applies to "all … phytosanitary measures which
may, directly or indirectly, affect international trade". Paragraph 1 of Annex A to the SPS Agreement clarifies, inter alia,
that "[a]ny measure applied: (a) to protect ... plant life or h ealth within the territory of th e Member from risks arising from
the entry, establishment or spread of pests" is a phytosanitary measure for purposes of the SPS Agreement.
228 Adopted 13 February 1998, WT/DS26/AB/R, stating as follows in paragraph 98: "The initial burden lies on the
complaining party, which must establish a prima facie case of inconsistency with a particular provision of the SPS
Agreement on the part of the defending party, or more precisely , of its SPS measure or measures complained about. When
that prima facie case is made, the burden of proof moves to the defending party, which must in turn counter or refute the
claimed inconsistency". See also the Panel Reports on EC - Hormones, op. cit., respectively, at paragraphs 8.51 and 8.54.
229 Appellate Body Report on United States - Measure Affecting Imports of Woven Wool Shirts and Blouses from
India, adopted 23 May 1997, WT/DS33/AB/R, p.14.

F. SCIENTIFIC BASIS AND RISK ASSESSMENT (ARTICLES 2.2, 5.1, 5.2 AND 5.7)
1. The SPS provisions invoked and their relationship
8.14 We first examine the US claims under Articles 2.2, 5.1 and 5.2. In this respect, Japan also
invokes Article 5.7. These Articles provide in relevant parts as follows:
Article 2.2:
"Members shall ensure that any … phytosanitary measure is applied only to the extent
necessary to protect … plant life or health, is based on scientific principles and is not
maintained without sufficient scientific ev idence, except as provided for in paragraph
7 of Article 5".
Article 5.1:
"Members shall ensure that their … phytosanitary measures are based on an
assessment, as appropriate to the circumstances, of the risks to … plant life or health,
taking into account risk assessment techniques developed by the relevant international
organizations".
Article 5.2:
"In the assessment of risks, Members shall take into account available scientific
evidence; relevant processes and production methods; relevant inspection, sampling
and testing methods; prevalence of specific diseases or pests; existence of pest- or
disease-free areas; relevant ecological and environmental conditions; and quarantine
or other treatment".
Article 5.7:
"In cases where relevant scientific evidence is insufficient, a Member may
provisionally adopt … phytosanitary measures on the basis of available pertinent
information, including that from the relevant international organizations as well as
from … phytosanitary measures applied by other Members. In such circumstances,
Members shall seek to obtain the additional information necessary for a more
objective assessment of risk and review the … phytosanitary measure accordingly
within a reasonable period of time".
8.15 We examine these provisions together, in ligh t of the following statement by the Appellate
Body in its report on EC - Hormones:
"... Articles 2.2 and 5.1 should constantly be read together. Article 2.2 informs
Article 5.1: the elements that define the basic obligation set out in Article 2.2 impart
meaning to Article 5.1".
230
8.16 The United States submits that Article 2.2 does not allow Japan to maintain a phytosanitary
measure, in this instance the varietal testing requirement, "without sufficient scientific evidence" and
that Article 2.2 requires such measure to be "based on scientific principles". According to the United

230 Adopted on 13 February 1998, WT/DS26/AB/R, paragraph 180. See also panel report on Australia – Measures
Affecting Importation of Salmon, currently on appeal, WT/DS18/R, paragraph 8.51: "We recall that Articles 5.1 and 5.2 may
be viewed as one of the specific applications of the basic obligations contained in Article 2.2".

States, Articles 5.1 and 5.2 require Japan to base the varietal testing requirement on a risk assessment.
We first examine the US claims under Article 2.2, taking due account of the more specific obligations
imposed under Articles 5.1 and 5.2.
2. Scientific basis
(a) Claims and arguments by the Parties
231
(i) The United States
8.17 The United States submits that, at a minimum, to base a measure on scientific principles a
WTO Member has to identify a particular risk that the measure is designed to protect against, and to
conduct some review of scientific evidence or other relevant scientific information to demonstrate that
the measure in fact protects against that risk. According to the United States, the risk to be addressed
in this case is the risk of introduction of codling moth in the absence of the varietal testing
requirement.
8.18 The United States notes that the strongest wording Japan has been able to employ is that it is
possible there may be variation in the efficacy of disinfestation if the same quarantine treatment is
applied to different varieties. Referring to the descriptions of variations in dose-mortality tests
232
between varieties, offered by Japan in support of the measure 233, the United States submits that these
descriptions ignore the conclusions of the scientific studies carried out on quarantine treatments for
codling moth. In this respect, the United States recalls that to date the quarantine treatment approved
for one variety of a product has always proven to be effective for all other tested varieties of the same
product. The United States submits that it tested seven varieties of apples, nine varieties of cherries,
four varieties of walnuts and ten varieties of nectarines and that in every instance the treatment
applied for one variety of a product has never varied from that applied to another variety of the same
product.
8.19 With respect to the six specific studies submitted by Japan
234, the United States points out that
all of the tests reported therein are dose-mortality tests which are small-scale tests. The United States
argues that the differences in dose-mortality tests for different varieties in these studies cannot
constitute a valid scientific basis for the varietal testing requirement because it is in the nature of dose-
mortality tests to vary among varieties and even within the same variety from year to year. The
United States points to leakage of the fumigation chamber, fruit load, experimental errors, sorption by
packaging material, natural variation of pest population and fruit-to-fruit variation such as different
ripening times, seasonal variations and physical condition of the fruit as factors explaining the
differential. According to the United States, confirmatory tests (which are conducted on a larger
scale) are a better indicator of efficacy of a treatment: since confirmatory tests take account of the
variability in (small-scale) dose-mortality tests, they establish a treatment that is appropriate for all
varieties of a product. The United States further submits that the highest minimum dose observed in
the dose-mortality tests that scientists believe would achieve the level of protection required by Japan,
is supplemented by a 10-20 per cent buffer in the second stage of testing (the confirmatory tests).
According to the United States, this buffer will offset all sources of variation in the dose-mortality
tests, including any possible varietal differences.

231 The parties' arguments with respect to Article 5.7, to which Article 2.2 explicitly refers, are outlined later in
paragraphs 8.50 and following.
232 The meaning of a "dose mortality test" is explained in paragraph 2.12.
233 Set out in paragraphs 8.21 and 8.23.
234 Ibid.

(ii) Japan
8.20 Japan responds that there is a sufficient amount of literature and scientific data which
indicates the possible presence of a statistically significant difference in the efficacy of known
disinfestation measures across varieties of the same product, and that such a difference could require
application of a different treatment.
8.21 First, Japan submits that in the specific case of MB fumigation the link between varietal
differences and the divergent efficacy of a fumigation treatment may manifest itself by way of a
difference in the CxT value for different varieties, i.e., a difference in the relationship between the
fumigant gas concentration in the fumigation chamber and the time-period of fumigation.
235 Japan
specifically refers to three studies which allegedly demonstrate a statistically significant difference in
CxT values between tested variety samples: 236 (1) 1985 tests on three varieties of American walnuts
where, according to Japan, CxT values were significantly different between the Franquett variety and
the Payne variety 237; (2) 1988 tests on three varieties of American nectarines where, according to
Japan, CxT values of the May Diamond variety showed a statistically significant difference from the
other two cultivars for most of the doses
238; and (3) 1997 tests on three varieties of Japanese
nectarines where there was, according to Japan, a statistically significant difference in CxT values
between the Shuhou variety and the Fantasia variety.239
8.22 According to Japan, differences in CxT values between varieties could be an indicator of
differences in the efficacy of a fumigation treatment. Japan argues as follows: When MB gas is
injected into the fumigation chamber to disinfest a particular load of fruit, it is absorbed by the surface
or the pulp of the fruit. If the degree of sorption varied depending on the variety of the fruit, the
amount of fumigant remaining in the chamber air will vary in an inverse relationship to the sorption.
Then the CxT value, which is determined by th e gas concentration remaining in the chamber and
which is a known indicator to control the degree of efficacy of the treatment, will vary as well
depending on the variety of the fruit. According to Japan, the physical and chemical properties of
fruits are factors affecting sorption (e.g., differences in oil content or a rougher surface) and can be
attributable to varietal characteristics. Therefore, Japan concludes, the reported differences in CxT
value are due to varietal differences and are an indicator of differences in the efficacy of a fumigation
treatment.
8.23 Second, Japan submits three studies, derived from dose-mortality tests
240, which indicate a
difference in LD 50 values (i.e., the level of dose required in the tests to kill 50 per cent of all codling
moths241) between tested variety samples: 242 (1) 1987 tests on six varieties of American nectarines
where, according to Japan, one of the varieties tested, namely Summer Grand, was found significantly

235 The concept of a CxT value is further explained in paragraph 2.11.
236 These studies are described in more detail in the descriptive part of our report, paragraphs 4.109 - 4.135.
237 Vail, P. V. et al., Walnut On-Site Operational (Demonstration) Test Report to Japanese MAFF, USDA/ARS,
Horticultural Crops Research Laboratory, Fresno, California, 2-14 December 1985.
238 Vail, P. V. et al., Report on Efficacy of Methyl Bromide for Codling Moth on Nectarines: Consideration of
Nectarines as a Product Group, Prepared for Approval by the Japanese MAFF, Horticultural Crops Research Laboratory,
Fresno, California, December 1988.
239 Research Division, Yokohama Plant Protection Station, MAFF, 1997, Unpublished.
240 The meaning of a "dose mortality test" is explained in paragraph 2.12.
241 The notion of LD values is further explained in paragraph 2.14.
242 These studies are dealt with in more detail in paragraphs 4.81 - 4.108.

more susceptible to MB fumigation (i.e., had a lower LD 50 value) than the others 243; (2) 1987/1988
tests on five varieties of New Zealand cherries where, according to Japan, the LD50 value for the Bing
variety was significantly lower than that for two of the other varieties tested, namely Rainer and
Sam244; and (3) 1983/1984 tests on two varieties of New Zealand nectarines where, according to
Japan, the Fantasia variety showed a significantly lower LD50 value than the Redgold variety.245
8.24 Japan agrees with the United States that there may be a range of exogenous factors (e.g.,
differences in leakage of the fumigation chamber, fruit load, experimental errors, sorption by
packaging material, natural variation of pest population and fruit-to-fruit variation such as different
ripening times, seasonal variations and physical condition of the fruit) which may also account for the
differential in CxT and LD
50 values reflected in the studies it refers to. However, Japan claims that
most of these other variables can be controlled in such a manner as to minimize their effects and that
such control is a normal practice for scientists. The Japanese hypothesis is that characteristics of a
particular variety may affect fumigation efficacy and that there is not sufficient evidence to disprove
this possibility. This is, according to Japan, a reasonable argument. For Japan, its policy of variety-
by-variety testing is therefore based on a scientific hypothesis which, in turn, is supported by
empirical data, in full conformity with the obligations contained in Article 2.2.
8.25 Japan acknowledges that existing treatment levels of host plants of codling moth have been
found effective for additional varieties. However, for Japan, all this proves is the efficacy of the
treatment on the tested varieties. According to Japan, this falls short of showing absence of varietal
difference within a product altogether. Japan notes that only a limited number of varieties have been
tested in full-scale trials. On the question of a buffer, Japan claims that in large-scale trials the buffer
is not always added to the "highest minimum dose", as the United States argues. Japan submits that in
some instances the amount of fumigant absorbed by, inter alia, bins or the interior of warehouses may
exceed the 10 to 20 per cent buffer. Japan further refers to Dr. Ducom's response to Panel question 12
relating to the buffer 246 and highlights the uncertainty of the effect of the buffer. On these grounds,
Japan concludes that the United States has not performed the required demonstration of efficacy of a
treatment across all varieties.
(b) Is the varietal testing requirement maintained without "sufficient scientific evidence" in the
sense of Article 2.2?
8.26 We first examine that part of Article 2.2 requiring Japan to "ensure that [the varietal testing
requirement] … is not maintained without sufficient scientific evidence".
8.27 We recall that Article 2.2 provides for an alternative to the requirement not to maintain
phytosanitary measures without sufficient scientific evidence, namely to adopt provisional measures
in accordance with Article 5.7. 247 Whether Japan can validly invoke Article 5.7 in this dispute, is
addressed below in paragraphs 8.48 and following.

243 Yokoyama V.Y. et al ., Methyl Bromide Fumigation for Quarantine Control of Codling Moth (Lepidoptera:
Tortricidae) on Nectarines, Journal of Economic Entomology 80, 1987, pp. 840-842.
244 Waddel, B.C. et al., Disinfestation of New Zealand Cherries, Cultivar Comparison Test 1987/1988, Department
of Scientific and Industrial Research, Auckland, June 1988.
245 Batchelor, T.A. et al., Disinfestation of New Zealand Nectarines 1983/1984, Department of Scientific and
Industrial Research, July 1984.
246 See paragraphs 6.87 and following.
247 Article 2.2 provides that "Members shall ensure that any … phytosanitary measure … is not maintained without
sufficient scientific evidence, except as provided for in paragraph 7 of Article 5" (emphasis added).

(i) The meaning of a measure "maintained without sufficient scientific evidence"
8.28 As referred to above 248, the general obligations in Article 2.2 have to be read together with
the more specific obligation imposed on Japan in Article 5.1, namely the obligation to ensure that the
varietal testing requirement is "based on" a risk assessment. The Appellate Body, in its report on EC
– Hormones, elaborated on the meaning of the term "based on" as used in Article 5.1 as follows:
"We believe that "based on" is appropriately taken to refer to a certain objective
relationship between two elements, that is to say, to an objective situation that persists
and is observable between an SPS measure and a risk assessment".249
"We believe that Article 5.1, when contextually read as it should be, in conjunction with
and as informed by Article 2.2 of the SPS Agreement, requires that the results of the risk
assessment must sufficiently warrant – that is to say, reasonably support – the SPS
measure at stake. The requirement that an SPS measure be "based on" a risk assessment
is a substantive requirement that there be a rational relationship between the measure
and the risk assessment".250
8.29 We consider this statement (with respect to Article 5.1) to provide guidance also for our
examination as to whether the varietal testing requirement is "maintained without" sufficient scientific
evidence (in the sense of Article 2.2). In our view, for a phytosanitary measure to be "maintained
without" sufficient scientific evidence, there needs to be a lack of an objective or rational relationship
between, on the one hand, the phytosanitary measure at stake ( in casu , the varietal testing
requirement) and, on the other hand, the scientific evidence submitted before the Panel ( in casu, in
particular the six studies referred to by Japan251).
8.30 When conducting this examination, we consider it to be important to make a clear distinction
between (1) the Japanese requirement that it is for the exporting country (in casu, the United States) to
demonstrate the efficacy of the quarantine treatment it proposes in order to gain access to the Japanese
market for certain products and (2) the Japanese requirement that the exporting country ( in casu, the
United States) needs to make such demonstration for each variety of a given product. The United
States does not contest the first requirement.
252 It accepts that it needs to demonstrate quarantine
efficacy. Only the fact that it needs to do so for each variety, i.e., only the second requirement (the
varietal testing requirement), is at issue in this dispute. Under Article 2.2, Japan has the obligation not
to maintain this requirement without sufficient scientific evidence.
253
8.31 Our task in this dispute is to determine whether or not Japan, to date , is in breach of this
obligation254; not whether in the future scientific evidence could be produced which would allow
Japan to comply with its obligation. 255 If to date there were not sufficient scientific evidence in

248 See paragraph 8.15.
249 Op. cit., paragraph 189, pp. 76-77, italics in original, underlining added.
250 Op. cit., paragraph 193, underlining added.
251 See paragraphs 8.21 and 8.23.
252 See paragraph 8.10.
253 Unless the Japanese measure is imposed in accordance with Article 5.7, a provision to which Article 2.2
explicitly refers. As noted earlier, this question is dealt with in paragraphs 8.48 and following.
254 In this respect, we recall the rules on burden of proof we set out earlier in paragraph 8.13.
255 Article 11 of the DSU directs us to "make an objective assessment of the matter before [the Panel], including an
objective assessment of the facts of the case".

support of the varietal testing requirement, Japan would be in breach of its obligations under the SPS
Agreement.256
(ii) The opinions of the scientific experts advising the Panel
8.32 To determine whether or not the varietal testin g requirement is maintained without sufficient
scientific evidence (i.e., whether there is a lack of an objective or rational relationship between the
measure at issue and the scientific evidence before the Panel), we need to refer to the opinions we
received from the experts advising the Panel. 257 We recall that these expert opinions are opinions on
the evidence submitted by the parties. We are not empowered, nor are the experts advising the Panel,
to conduct our own risk assessment.258
8.33 At the end of our meeting with the experts advising the Panel, we requested them to confirm a
number of understandings we had drawn from their answers and statements. The experts
unanimously confirmed the following understandings:
• First, referring to the eviden ce before the Panel, there may be differences between
varieties of the products in dispute which may, in turn, be relevant for quarantine
purposes, i.e., which may affect the efficacy of an MB treatment approved for one
variety of a product if applied to another variety of the same product.259
• Second, the question whether varietal differences, if any, are significant for
quarantine purposes cannot be determined on the basis of the evidence before the
Panel.260

256 Assuming the measure cannot be considered to be a provisional measure in accordance with Article 5.7, an
issue we examine below in paragraphs 8.48 and following.
257 For the procedures we followed to appoint these experts and to obtain their views, see paragraphs 6.1 and
following.
258 See also panel report on Australia – Salmon, op. cit., paragraphs 8.41, 8.126 and 8.172.
259 See Transcript, paragraphs 10.268 - 10.273. Dr. Heather stated the following (confirmed by the other two
experts):
"My understanding, my belief is not that there are differences but there may be differences. I
don't believe that the occurrence of the differences has been proven and that they may be
relevant for quarantine purposes. So there are two sets of uncertainties in my mind in this
statement. There's no certainty that even if differences exist that they are relevant for
quarantine purposes between varieties of the products in dispute" (Transcript paragraph 10.270,
underlining added).
260 See Transcript, paragraphs 10.274 - 10.279. As noted in the previous footnote, Dr. Heather stated
unambiguously:
"I don't believe that the occurrence of the differences has been proven and that they may be
relevant for quarantine purposes".
See also the introductory statement by Dr. Ducom:
"the questions of the Panel are relevant but often there is no clear response to give because we
miss data on the exact subject on variety by variety testing" (Transcript, paragraph 10.39,
underlining added).
See also Mr. Taylor:
"one of the things that has come out from this meeting which I have found extremely interesting
is that we do need more information before we can say categorically that variety in fruit is a

• Third, if, and to the extent that, differences between varieties are significant for
quarantine purposes, they are mainly or even exclusively related to different levels of
sorption of the fruit.261
As noted earlier262, the scientific evidence before the Panel (i.e., the evidence evaluated by the experts
advising the Panel) relates to either apples, cherries, nectarines or walnuts. However, in the view of
the experts advising the Panel the understandings referred to above equally apply to the other products
at issue (apricot, pear, plum and quince).263
8.34 Replying to a US question (posed at the meeting with the experts) as to whether the experts
are aware of any situation where differences in vari ety have resulted in a different treatment level for
the products at issue in this case, Mr. Taylor stated: "No, I have no information or have seen any
published data so the answer I have to give is no"; Dr. Heather replied: "In my experience there have
been no differences of this kind. In fact it's been to the contrary. Most of my experience has been with
insecticide dips with the material dimethoate and here we find that the same treatment not only goes
across varieties but across commodities but I can see that this sorption problem with methyl bromide
is something very special and that's why I wish to defer to my colleagues with experience as
fumigation experts".264
8.35 When we asked the experts advising the Panel whether, in their expert opinion, there is an
objective or rational relationship between, on the one hand, the varietal testing requirement imposed by
Japan for MB treatment and, on the other hand, any of the evidence submitted by the parties, they stated
unanimously that – even though in theory there may be relevant varietal differences – to date there is not
sufficient evidence in support of the varietal testing requirement.265

major factor affecting the efficacy of treatment" (Transcript, paragraph 10.266, underlining
added).
261 Transcript, paragraphs 10.280 - 10.285. See also, for example, the introductory statement by Mr. Taylor:
"So I would just say then that sorption seems to me to be something that we need to know more
about. If it can be shown that the levels of sorption are such that they are significant enough to
remove the fumigant to an extent that it is going to raise some doubt as to the efficacy of the
treatment, then of course we could say that varietal testing was necessary. But unless we can
show that it seems to me that the need to te st by variety does still need to be established.
(Transcript, paragraph 10.48, underlining added).
See also Mr. Taylor, Transcript, paragraph 10.140:
"I don't think any of us are in dispute that sorption would be a major factor affecting the
efficacy of treatment, and if it can be demonstrated that sorption is of sufficient magnitude
between different varieties, this would affect the efficacy of treatment, but I think that this has
still to be shown and to be demonstrated" (underlining added).
262 See paragraph 8.6.
263 Transcript, paragraphs 10.223 - 10.225.
264 Transcript, paragraphs 10.155 - 10.158. The question was not directed at Dr. Ducom who did not answer it.
265 Transcript, paragraphs 10.167 - 10.174:
Dr. Ducom: "… the arguments are not statistically good. Scientifically, they may be good, but in
practice they may be too narrow. But the answer is really difficult".
Mr. Taylor: "I have to agree with Dr. Ducom. The answer is very difficult otherwise perhaps we
would not be here. Again I think in theory there may be some differences which perhaps exist, but in
practice it is difficult to show these and it seems very difficult in fact to sa y that at this time the
differences that might make the difference between treatments efficacious and non-efficacious have not

8.36 In his written answer to Panel question 16, Dr. Ducom states the following:
"The arguments put forth by Japan for requiring varietal trials are not based on
scientific data. They are supported by a few experimental data in which varietal
difference exists, in terms of LD 50, among a lot of other data in which it does not.
These observations lead them to suspect all existing varieties and even more so those
of the future, in which, in their eyes, genetic engineering and biotechnology might
well create even greater differences. This is not based on any scientific data".266
8.37 According to the experts advising the Panel, ther e is scientific evidence before us – in the
form of small-scale dose-mortality tests 267 carried out on different varieties of the same product –
which indicate different test results (either a different CxT value 268 or a different LD 50 value269) for
different varieties. 270 This cannot be disputed. The statistical and biological relevance of the
differences in these test results and, especially, the factors causing them are less clear.
8.38 First, the experts advising the Panel question the value to be attached to the test results for
purposes of checking quarantine efficacy. 271 They express doubts as to whether LD 50 values derived
from dose-mortality tests can be used to compare the efficacy of quarantine treatment between
varieties.272 They also note that even though the test results – both with respect to CxT and LD 50

yet been reached and therefore I think at this moment in time that the evidence is not sufficiently strong
although in theory it does have some possible validity. But at this stage, as Dr. Ducom has said, and in
practical terms, it's very difficult to say yes there is something which is sufficiently demonstrated to show
that there is a real problem which has to be addressed in terms of maybe variety-by-variety testing, and
which could lead to differences in the treatment techniques that are used".
Dr. Heather: "More to agree with both of my colleague s. I'd say yes there is a relationship but it is
an incomplete one but this is a real world and to to tally complete the relationship of these and decide on
how important it is, I think would probably be beyond the resources even of the United States and Japan
in the time available, and I'm not sure that it would really add anything of great value to the argument".
266 See paragraphs 6.104 - 6.105.
267 The concept of a dose-mortality test is explained in paragraph 2.12.
268 The concept of a CxT value is explained in paragraphs 2.11 and 8.21.
269 The concept of an LD50 value is explained in paragraphs 2.14 and 8.23.
270 See paragraphs 8.21 - 8.23.
271 In this respect, it should, from the outset, be recalled that all the studies referred to by Japan were designed and
carried out in order to comply with the varietal testing requirement. None of the studies before us specifically examines the
appropriateness of the requirement itself.
272 See answers to Panel question 1 by Dr. Ducom: "In practice, the LD50 test constitutes a fairly unreliable
method to compare the efficacy of quarantine" and Mr. Taylor: "LD50 values are extremely useful in comparing the toxicity
of different chemicals and in the measurement of resistance. However, these values are less useful in investigations of much
higher levels of toxic response such as are necessary in relation to quarantine treatments, where LD values of 99 or 99.9 are
more appropriate and useful". In his answer to Panel question 12, at para. 6.8, however, Dr. Ducom noted that "while the dose-
mortality test (LD 50) did not give any confidence in respect of the varietal factor, it did give an indication of the relative
sensitivity of the products tested". See also Dr. Heather's statement at the meeting with the experts:
"[The LD50 value] is not a precise numerical measure and of necessity it has had to be used in a
rather less precise way than it would otherwise be. It is not a direct measurement on the insect,
it is a measurement on the insect where it is influenced by the fruit in the chambers so it is not a
precise measurement. In fact, if you look at an LD value it's easy to take one figure but
realistically you should be looking at what we call the confidence limits or the fiducial limits
and these are ranges within which that value falls and perhaps would lead to a better
understanding if we thought of it in that way. As you r ecall, because the quarantine treatments
are not measured at the median dose or the LD
50 dose but at the extreme dose, these limits

values – show statistical differences between varieties, biologically speaking these differences are not
pronounced.273
8.39 Second, and more importantly, the experts advising the Panel are of the view that even if
confidence is given to these differences in the test results there is no evidence before the Panel that
these differences – both in CxT and LD50 values – are due to varietal differences.
8.40 In the studies referred to by Japan, the same tests were carried out on different varieties and in
some instances the results differed. However, according to the experts advising the Panel, these
differences could have been caused by a series of factors which are not related to varietal differences,
such as differences in leakage of the fumigation chamber, fruit load, experimental errors, sorption by
packaging material, natural variation of the pest population and fruit-to-fruit variation such as
different ripening times, seasonal variations and physical condition of the fruit. Japan contends that
experimental factors can be and were controlled to the extent possible. However, Japan does not
contest that other factors (not related to varietal differences) could also explain the differences in the
test results. The differences might also be linked to varietal differences. However, on this Dr. Ducom
states the following (confirmed by the other two experts advising the Panel274):

become very wide and it is not wise to take arithmetic cognizance" (Transcript, paragraph
10.41).
273 At the meeting with the experts Dr. Ducom stated:
"… the scientific facts given by Japan are may be too narrow. I mean, for example, when they
give some differences between varieties the confidence limit is not a biological fact, it is a
statistical fact. I mean, biologically speaking, the difference does not matter … just one per
cent makes, statistically speaking, there is a significant difference while biologically speaking
there is no difference" (Transcript, paragraph 10.39. See also Dr. Ducom at Transcript, paragraph
10.186).
See also the statement by Dr. Heather at the meeting with the experts:
"… statistically demonstrated differences … must always be viewed against the background of
the biological conditions which give rise to them. What is biologically unlikely, but
statistically shown, must be viewed with some reserve. Biological creditability is just as
important as statistical demonstration of differences." (Transcript, paragraph 10.43).
274 Addressing, for example, a study conducted on three varieties of nectarines and 13 apple varieties (Kawakami, F.,
et. al., Methyl Bromide Sorption in Fruit Varieties, Research Division, Yokohama Plant Protection Station, Japan Exhibit 36),
Dr. Heather, speaking on behalf of all three experts, stated:
"… the authors obviously attributed the differences to varietal characteristics. We are of the
opinion that it is not possible to attribute them solely to varietal characteristics on the evidence
that's present in this paper. It may well be true but it requires, it would require… to reach that
firm conclusion would require more information." (Transcript, paragraph 10.218).
With respect to the same study, Dr. Ducom noted the following:
"This study was very interesting but the problem is that it was made on apples, which were not
at the same stage of storage because some were one month in storage and others had three
month's storage – so the variety is not the only factor which can change the value we can read.
So in practice that means that varieties may be a factor but maybe not very important and
maybe some other factors influence that data. The problem of all these studies is that they are
just descriptive studies. We take some apples, or peaches, or nectarines, and we look at the
concentration but the reason why it differs, we don't know. There is no fundamental work on
that and we can just say this works, or it does not work and so on" (Transcript, paragraph
10.259, underlining added).
See also Dr. Heather's answers to Panel question 1: "… where differences between varieties are small, fruit to fruit variation
could greatly exceed variety to variety variation. Such variation is an inherent characteristic and is usually overcome by

"It is impossible by a simple DMT [dose-mortality test] to find out the relevant impact of the
factors playing a role in the varietal differences … mainly because varieties ripen at different
times … The DMT presented by the parties are designed to give information on insect
sensitivity. The search for possible causes of varietal variations cannot be determined with
precision by them, but only with a specific research program".
275
"There is a lack of precise studies on this subject. A priori, one could cite almost anything, the
size of the fruit, the nature of the epidermis, the average sugar content, the ripeness of the
fruit, its physiological condition, the time between harvest and fumigation, etc. However, in
this, there are hypotheses that merit studying".
276
8.41 The experts advising the Panel point out that so far no attempt has been made to determine
whether varietal differences actually constitute a factor which causes the differences in the test
results.277 And this even though, according to the experts advising the Panel, technically speaking
such determination can relatively easily be made, for example, by conducting sorption tests on
different varieties of a product. 278 Japan did not further test or try to confirm its so-called hypothesis

ensuring adequate robustness of the treatment"; to Panel question 3: "Although statistical differences are evident between
some varietally based experiments, this does not provide an assurance that the origin of the difference lies predominantly in
varietal characteristics"; and to Panel question 8: "If the criterion used is statistically significant differences between
experimental samples of different varieties there are differences as identified by Japan, but there is no certainty that they a re
attributable to unique varietal characteristics. In subsequent research on additional varietal samples these differences were
too small to cause the efficacy of a treatment based on varieties used in initial trials, to fail in further testing".
275 Dr. Ducom's answer to Panel question 3.
276 Dr. Ducom's answer to Panel question 9. Answering a US question at the meeting with the experts – as to
whether varietal differences are widely known to result in significant differences in efficacy of treatment as opposed to a
number of sources of fruit variation which include temperature, moisture, daylight, rainfall, cultivation conditions and other
natural conditions of the harvest year, which according to Japa n are not widely known to result in significant differences in
efficacy of treatment – Dr. Ducom stated as follows:
"It's the same. My opinion is that differences are of the same [nature], maybe, of the same
amount [importance]. I mean, I do not understand what Japan says. I mean why temperature,
moisture and so on? Since they are not known they are counted for nothing. That I cannot
understand. The same thing for variety. If we use the same argument varieties [aren't more
significant than other variables] are just nothing because [we have little data for varieties] we
don't know the answer for varieties. Or, if we take into account variety we should take into
account daylight, moisture, rainfall and so on" (Transcript. paragraph 10.62).
277 See footnote 260.
278 Since, according to the experts advising the Panel, varietal differences, if and to the extent they exist, would
mainly or exclusively be due to differences in sorption, tests could, for example, be conducted on different varieties of a
product to check whether there are any such differences in sorption. See Dr. Ducom's statement at the meeting with experts:
"I just advise something about sorption. Levels are important for varieties but that means no
insects, no LD50 trials to show that sorption is different. I mean we don't need any insects and
any dose mortality tests to show that sorption is different and it makes very different, it's very
easy, it's easier to run a sorption test than the dose mortality test. That's an important point in
practice" (Transcript, paragraph 10.142).
See also the following statement of Mr. Taylor at the meeting with the experts:
"I think we're all agreed that sorption is one of the major factors involved and, I think that, as
Dr. Ducom said earlier, one of the things that shou ld be done is the testing of samples just with
methyl bromide [no insects to be involved] to see if we can determine the extent to which these
varieties do absorb methyl bromide. Also it would be nice to try and relate any differences we
find to chemical or physical characteristics more definitely" (Transcript, paragraph 10.266).
See also statements by Dr. Ducom and Mr. Taylor, Transcript, paragraphs 10.187 - 10.196.

according to which varietal differences affect quarantine efficacy. However, as Japan itself notes:
"The task of scientific demonstration begins, not ends, with a discovery of variables".279
(iii) Evaluation by the Panel
8.42 We carefully reviewed all the evidence before the Panel in accordance with the rules on
burden of proof we set out earlier. 280 After this review and referring, in particular, to the expert
opinions quoted above281, we consider that, to date, it has not been sufficiently demonstrated that there
is a rational or objective relationship between the varietal testing requirement and the scientific
evidence submitted to the Panel. In our view, the United States established – on the basis of scientific
reports and with the support of the opinions of the experts advising the Panel
282 – that so far not a
single instance has occurred in Japan or any other country, where the treatment approved for one
variety of a product has had to be modified to ensu re an effective treatment for another variety of the
same product. We acknowledge that this part of the evidence before us, of course, only relates to
those products and varieties for which to date an application for approval to import was made. The
United States further provided evidence, supported by the opinions received from the experts advising
the Panel, which suggests that varietal differences do not matter for quarantine efficacy, at least not to
the extent reflected in the current Japanese varietal testing requirement.
283 Moreover, even though
Japan may have some data – taken from several individual studies – possibly hinting at relevant
varietal differences, no evidence before this Panel makes the actual causal link between the
differences in the test results and the presence of varietal differences. On these grounds and after
having carefully weighed the evidence and opinions of the experts advising the Panel submitted to us,
we thus consider that the United States has raised a presumption that Japan's varietal testing
requirement is maintained without sufficient scientific evidence and that this presumption has not
been sufficiently rebutted by Japan.
8.43 We thus find that Japan maintains the varietal testing requirement without sufficient scientific
evidence in the sense of Article 2.2.
8.44 According to the scientific experts advising the Panel, the statements they provided on
varietal differences are – to the best of their knowledge – equally valid for all US products here at
issue.
284 At the meeting with the experts, we asked them the following:
"You know that the scope of this dispute does not cover only the four products,
apples, cherries, nectarines and walnuts, but also apricots, plums, pears and quince,
even if we have not received any material from either party concerning those four
other products. So now the Panel wants to ask you the following question: To the
best of your knowledge is what you have stated about varietal differences concerning
apples, cherries, nectarines and walnuts, w ould that also be valid for apricots, plums,
pears and quince?".285

279 Second submission of Japan, p. 15.
280 See paragraph 8.13.
281 See paragraphs 8.32 - 8.41.
282 See paragraph 8.34.
283 See, for example, paragraphs 8.35, 8.39 and 8.40.
284 See paragraph 8.33 in fine and footnote 263.
285 Transcript, paragraphs 10.223 - 10.225.

We put this question before the experts since the scope of our mandate covers all eight products286 and
taking into account the Appellate B ody's view that a panel needs to make findings with respect to all
products falling within its terms of reference.287
8.45 Dr. Heather answered "yes" to this question and the other two experts concurred. However,
the experts did not further elaborate on their answer. Nor did any of the parties provide any additional
comments or information which could enlighten us as to the existence or relevance of varietal
differences for the four products for which no specific studies are before us. After careful
examination we do not consider, therefore, that there is sufficient evidence before us to extend our
finding in paragraph 8.43 also to apricots, pears, plums and quince. We only find that Japan
maintains the varietal testing requirement without sufficient scientific evidence with respect to apples,
cherries, nectarines and walnuts.
8.46 With respect to two of the four products to which our finding in paragraph 8.43 does apply
(apples and walnuts), the experts advising the Panel made certain additional remarks. First, with
respect to apples and the cold treatment they undergo before entering Japan (in addition to
fumigation), the experts advising the Panel were even more categorical in their opinion that no
evidence before the Panel provides a causal link between varietal differences and a divergent efficacy
of the required treatment. Since, according to th e experts advising the Panel, the efficacy of cold
treatment is not linked to the sorption characteristics of the fruit – the allegedly most important factor
which could explain possible varietal differences, if any exist
288 – most (if not all) varietal differences
which might exist would be offset by the cold treatment. 289 One expert advising the Panel noted,
however, that cold treatment kills the codling moth eggs whereas MB fumigation kills the larvae. 290
The quarantine efficacy across varieties of apples due to the cold treatment would thus only seem to
apply to the killing of codling moth eggs.

286 See paragraph 8.6.
287 See Appellate Body report on Japan – Taxes on Alcoholic Beverages , adopted on 1 November 1996,
WT/DS8/AB/R, p. 26.
288 See paragraph 8.33 and footnote 261.
289 In reply to the Panel's question whether "anything in the apples study submitted by Japan [Kawakami, F., et. al.,
Methyl Bromide Sorption in Fruit Varieties, Research Divi sion, Yokohama Plant Protection Station, Japan Exhibit 36]…
change any of your earlier opinions as to the relevance of varietal differences for quarantine efficacy", Dr. Heather replied:
"I don't think there is anything in the apple study which impinges on this. Apples are unique in
that they have a combined treatment of cold and of methyl bromide and both of these are quite
efficacious in their own way. Perhaps I should say at this stage there was a question also from
Japan as to why I believe that apples would not differ very much amongst themselves
varietally. The reason for this is that cold treatment as a contributing treatment to the codling
moth control does not have a sorption proble m so there should not be the same degree of
variation between varieties of apples because of this cold treatment factor that you would find
in a treatment which relied only on methyl bromide" (Transcript, paragraph 10.257).
See also Dr. Heather's reply to Panel question 17:
"… given the combined lethal potential and broad applicability of MB and cold, it is highly
unlikely that there would be any differences in efficacy between any common commercial
apple varieties".
290 In his comments on the Panel's draft findings now contained in paragraphs 8.73 - 8.101 (received
according to the procedure outlined in paragraph 6.116), Dr. Ducom clarified that the combined treatments for
apples (MB fumigation and cold treatment) affect two different stages of the codling moth: the cold treatment kills
the codling moth eggs, the MB fumigation the larvae (see summary in paragraph 6.114). Dr. Ducom noted the
following: "There are indeed two treatments for apples, but they apply to two different and separate stages. The
cold kills the eggstage and the gas the fifth larval stage" (translation from French)".

8.47 Second, with respect to walnuts, the experts advising the Panel pointed at a specific factor
which may influence the sorption level of walnuts, namely their oil or fat content. This could also
explain the different test results referred to by Japan.
291 However, according to the experts advising
the Panel, so far no information is available which shows that the total oil content is a varietal
characteristic which could – by means of a different sorption level – affect the quarantine efficacy of
an MB treatment. 292 Therefore, the fact that no evidence before this Panel makes the causal link
between the differences in the test results and the presence of varietal differences, also applies to
walnuts.
(c) Is the varietal testing requirement a provisional measure under Article 5.7?
8.48 At this juncture – and before we can find, following our considerations and finding in
paragraphs 8.42 and 8.43, whether or not Article 2.2 is violated in this dispute – we recall that
Article 2.2 provides that "Members shall ensure that any … phytosanitary measure … is not
maintained without sufficient scientific evidence, except as provided for in paragraph 7 of Article 5 "
(emphasis added). We note that Japan invokes Article 5.7 in support of its varietal testing
requirement. We therefore need to examine next whether the varietal testing requirement is a measure
meeting the requirements in Article 5.7. If the varietal testing requirement meets these requirements,
we cannot find that it violates Article 2.2.
8.49 Article 5.7, in relevant parts, provides as follows:
"In cases where relevant scientific evidence is insufficient, a Member may
provisionally adopt … phytosanitary measures on the basis of available pertinent
information, including that from the relevant international organizations as well as
from … phytosanitary measures applied by other Members. In such circumstances,

291 See paragraph 8.21.
292 As outlined in paragraphs 6.112 - 6.115, after the Panel's second substantive meeting, we addressed an
additional question to the experts dealing with walnuts (with reference to a study submitted by the United States, Variation
in Polyunsaturated Fatty Acids Composition of Persian Walnut, L. Carl Greve, et. al., J. Amer. Soc. Hort. Sci. 117 (3), pp.
518-522, 1992, US Exhibit 40) namely "whether and to what extent the oil or fat content differs between varieties of walnuts
because of varietal characteristics " and "whether any such differences are significant enough to affect quarantine efficacy"
(emphasis in original). Dr. Heather answered, inter alia:
"I did not find any information on total oil content as a varietal characteristic … Therefore, [the
US study] does not provide any further clarification of the extent to which oil content of
walnuts might affect quarantine treatment efficacy and consequently, quarantine security".
Dr. Ducom stated, inter alia:
"… the differences between varieties in walnut commodities could be, if any, easily showed
since we have a very good tool with the oil content … variety is one of the different factors
which may affect the oil content of the fruit. But the authors have shown that it's influence is
less important than the environmental conditions … Differences like presented in the
publications seem to be not large enough to have a noticed influence on the sorption and thus
on CT and efficacy. But only trials designed for that purpose could definitively give the good
answer".
Mr. Taylor stated, inter alia:
"The greater differences in fatty acid content composition found from year to year within the
same variety than between varieties in a single year is also very important evidence
demonstrating that varietal differences are unlikely to be the most important factor affecting
sorption of methyl bromide and, therefore, the efficacy of methyl bromide fumigations".
See also the statements by Mr. Taylor, Transcript, paragraph 10.140 and by Drs. Heather and
Ducom, Transcript, paragraphs
10.290 - 10.292.

Members shall seek to obtain the additional information necessary for a more
objective assessment of risk and review the … phytosanitary measure accordingly
within a reasonable period of time" (underlining added).
(i) Arguments by the parties
8.50 Under Article 5.7, Japan argues that the rationale for its varietal testing requirement is that
"available pertinent information" suggests a possible presence of varietal differences in the efficacy of
a disinfestation treatment. Once the import prohibition is lifted for a particular variety, Japan expects
that new data will be accumulated on the effects of the treatment approved for that variety in order to
reach a sufficient level of confidence as to the broader applicability of that treatment to other varieties.
Until such level of confidence is achieved, Japan claims to have the right to maintain, on a provisional
basis, the import prohibition for all other varieties of the same product. In this respect, Japan further
submits that it has not been demonstrated that the present treatment for any of the US products
allowed for import will control the risk at the required level with respect to all other varieties.
8.51 Japan recognizes, however, that under Article 5.7 it is required to "seek to obtain the
additional information necessary for a more objective assessment of risk and review the …
phytosanitary measure accordingly within a reasonable period of time". In this respect, Japan submits
that its obligation to collect information is discha rged by Japan's practice of requiring the exporting
countries to submit data each time approval of additional varieties is sought, as well as by MAFF at the
Yokohama Plant Protection Station (Research Divisi on) which is seeking to collect information and
continues to study the effectiveness of the existing treatments for new varieties.
8.52 In response, the United States submits that Japan's construction of Article 5.7 is patently
incorrect. For the United States, Article 5.7 has a threshold requirement that in order for a measure to be
provisional, there must be an insufficient amount of relevant scientific evidence to be able to perform a
risk assessment. According to the United States, in this case there is a sufficient amount of evidence.
For the United States, all evidence in this case, including the success of uniform treatments on different
varieties exported to Japan and the absence of failures by commodity-based testing regimes in other
countries, indicates that varietal differences do not affect treatment efficacy.
8.53 The United States further submits that it strains credulity to describe a 50-year old measure as
"provisional". The United States argues that, contra ry to what is required in Article 5.7, there is no
evidence that Japan has undertaken a process to produce a more objective assessment of risk "within a
reasonable period of time" so that it can review whether the "provisional measure" should be continued.
(ii) Evaluation by the Panel
8.54 In our view, the first sentence of Article 5.7 allows Members to provisionally adopt
phytosanitary measures if two elements, cumulative in nature, are met:
• the measure is imposed in respect of a situation where "relevant scientific information
is insufficient"; and
• the measure is adopted "on the basis of available pertinent information".
However, even if a measure meets both of these elements, the second sentence of Article 5.7 imposes
additional obligations on the Member provisionally adopting the measure, namely the obligation to
• "seek to obtain the additional information necessary for a more objective assessment
of risk"; and
• "review the … phytosanitary measure accordingly within a reasonable period of
time".

8.55 Therefore, even if we were to assume that the varietal testing requirement is a phytosanitary
measure provisionally adopted in accordance with the first sentence of Article 5.7, i.e., even if we
were to assume that in this case "relevant scientific information is insufficient" and there is "available
pertinent information" before the Panel on which Japa n can base the varietal testing requirement, the
second sentence of Article 5.7 obliges Japan to "seek to obtain the additional information necessary for
a more objective assessment of risk" and to "review the … phytosanitary measure accordingly within a
reasonable period of time".
8.56 As to the obligation imposed on Japan to "seek to obtain the additional information necessary
for a more objective assessment of risk ", Japan refers to the fact that exporting countries provide
additional information when they apply for access. We note, however, that the studies these countries
provide are designed and carried out to comply with the varietal testing requirement. They do not
examine the appropriateness of the requirement itself. This is also the case for the two reports before the
Panel which were carried out by MAFF's Research Division.
293 No further information or evidence was
submitted to us. As pointed out earlier 294, not a single study before the Panel actually addresses the
specific issue as to whether varietal characteristic s cause a divergency in quarantine efficacy. The
requirement that the information necessary to re view an SPS measure must be specific enough, was
referred to by the Appellate Body in EC – Hormones .295 In this respect, we further recall that the
experts advising the Panel stated that a study or research project to determine whether varietal
differences do matter for quarantine efficacy – which would mainly involve sorption tests – could be
carried out relatively easily.
296
8.57 Moreover, with respect to the obligation imposed on Japan to " review the … phytosanitary
measure accordingly within a reasonable period of time ", we note that, according to Japan, testing
variety-by-variety for lifting the import ban imposed in the Plant Protection Law, was first applied in
1969 when the ban was lifted for Hawaiian papayas of the Solo variety, i.e., on a variety basis. For the
US products at issue, hosts of codling moth, the import ban was first lifted in 1978. The issue of
varietal testing, and the question as to whether it can be scientifically justified, has thus been around for
almost 30 years and, with respect to the specific produc ts and pest at issue, for 20 years. During this
period of time Japan has been in a position to obtain further information on varietal differences and their
relevance to quarantine efficacy. Moreover, since the entry into force of the SPS Agreement on 1
January 1995, Japan has been under an explicit obligation to collect additional information to enable it
to more objectively review the appropriateness of the varietal testing requirement.
8.58 On these grounds, we consider that there is no evidence before us which indicates that Japan
sought to "obtain the information necessary for a more objective assessment of risk" and reviewed the
varietal testing requirement accordingly "within a reasonable period of time". We consider, therefore,
that the United States has established a presumption that Japan did not comply with the requirements in
the second sentence of Article 5.7. We also consider that Japan has not been able to rebut this
presumption.
8.59 Following the rules on burden of proof we set out earlier
297, we thus find that even if the
varietal testing requirement were considered as a provisional measure adopted in accordance with the

293 All but two of the studies before the Panel were conducted on behalf of exporting countries. The two exceptions
are two studies carried out by MAFF's Research Division (1997 tests on three varieties of Japanese nectarines, Research
Division, Yokohama Plant Protection Station, MAFF, 1997, Unpublished, Japan Exhibit 16 and Kawakami, F., et. al., Methyl
Bromide Sorption in Fruit Varieties, Research Division, Yokohama Plant Protection Station, Japan Exhibit 36).
294 See paragraph 8.42: no evidence before this Panel ma kes the causal link between th e differential in the test
results and the presence of varietal differences.
295 Op. cit., paragraph 200.
296 See footnote 278.
297 See paragraph 8.13.

first sentence of Article 5.7298, Japan has not fulfilled the requirements contained in the second sentence
of Article 5.7.
8.60 In its comments on the interim report, Japan not ed that the information gathered through
successive demonstrations by exporting countries c onstitutes experience and that experience is a
legitimate means to gather information under Article 5.7. We agree with this point of view. Of course,
Japan can take into account the evidence submitted so far by exporting countries. However, in our view,
this method of collecting information has, to date, not provided the information "necessary for a more
objective assessment of risk" and an appropriate revi ew of the varietal testing requirement "within a
reasonable period of time".
(d) The Panel's conclusion under Article 2.2
8.61 We have found above that the varietal testing requirement – in so far as it applies to imports
of apples, cherries, nectarines and walnuts – is neither (1) maintained with sufficient scientific
evidence in the sense of Article 2.2 299 nor (2), in the event it were a provisional measure in accordance
with the first sentence of Article 5.7, a measure maintained in conformity with the second sentence of
Article 5.7.300 We recall, however, that Article 2.2 requires Japan to ensure that the varietal testing
requirement is "not maintained without sufficient scientific evidence, except as provided for in
paragraph 7 of Article 5". Consequently, we come to the conclusion that Japan, by maintaining the
varietal testing requirement with respect to apples, cherries, nectarines and walnuts, acts inconsistently
with its obligations under Article 2.2.
8.62 Given this conclusion under Article 2.2, we see no need to further examine what is required for
a phytosanitary measure to be "based on scientific principles" in the sense of Article 2.2, nor to
determine whether in this dispute the varietal testing requirement is so based.
3. Risk assessment
8.63 Since we have found earlier301 that the varietal testing requirement violates Article 2.2, we see
no need to further examine whether it also needs to be based on a risk assessment in accordance with
Articles 5.1 and 5.2 nor to determine whether in this dispute it is so based.
G. MEASURES NOT MORE TRADE-RESTRICTIVE THAN REQUIRED (ARTICLE 5.6)
1. Arguments by the parties
8.64 The United States further claims that the Japane se varietal testing requirement is inconsistent
with Article 5.6 in that it is significantly more trade-restrictive than required to achieve Japan's
appropriate level of phytosanitary protection. The United States submits that because there are no
varietal differences that affect the efficacy of a quarantine treatment, the same established treatment
will achieve for all varieties of a product the appropriate level of protection. The United States argues
that neither it, nor any other country exporting to Japan, has ever had to modify a quarantine treatment
for codling moth for additional varieties of the same product. According to the United States, these

298 See paragraph 8.54.
299 See paragraph 8.42.
300 See paragraph 8.58.
301 See paragraph 8.61.

results conclusively demonstrate that Japan's variet al testing requirement has no value in providing
additional quarantine protection.
8.65 The United States posits testing by product as a reasonable alternative under Article 5.6. The
United States accepts that the first variety of a particular product from any source should be subject to
the full gamut of testing. However, it is the US view that after such validation, no further testing at all
for additional varieties is necessary. Because testing by variety takes a minimum of 2-4 years to
complete per variety, is resource intensive and costly to perform, and seriously delays market access
of US products, the United States argues that testing by product is also less trade-restrictive.
8.66 The United States submits that to be required to only conduct confirmatory tests for each
additional variety (as referred to in a question by the Panel to the United States), would be virtually as
time-consuming and burdensome as the current requirement to do dose-mortality tests for each variety
and confirmatory testing on representative varieties.
8.67 Although the United States pointed out, in its rebuttal submissions, that it considers testing by
product to be the only acceptable quarantine measure in the context of this dispute, in its oral
statement at the second substantive meeting it also referred to an alternative measure posited by the
experts advising the Panel
302 as a confirmation of the fact that Japan's varietal testing requirement is
more trade-restrictive than required. 303 The alternatives submitted by the experts advising the Panel
are outlined below.304
8.68 Japan responds that its lifting of the import prohibition for specific varieties is a result of the
discharge of its obligation under Article 5.6. According to Japan, whenever it finds a measure which
achieves its appropriate level of protection and is significantly less restrictive, the import prohibition
is replaced with such a measure. In this particular case, however, Japan submits that it found data
which suggests the presence of varietal differences in efficacy of MB fumigation, and a hypothesis
which explains such a variation. On that basis Japan requires testing by variety. As the United States
has not proven product-wide efficacy, Japan concludes that it should not be obliged to accept the US
alternative at this stage.
8.69 Japan points out that it already made efforts to alleviate the burden put on exporting countries.
First, Japan accepts the concept of a representative variety. This means, for example, that for an
application for access of five varieties of a product, a large-scale confirmatory test will only need to
be carried out for one of the five varieties, i.e., the variety which is shown to be the least sensitive to
the treatment in dose-mortality tests. This is why, Japan submits, there is no requirement of full-scale
testing of each variety. Second, for approval of additional varieties, the number of codling moth
insects required in large-scale demonstrations has been reduced from 30,000 to 10,000.
2. Elements under Article 5.6
8.70 We note that Article 5.6 provides in relevant part:

302 An approach to treatment based on a fixed CxT value to be met by monitoring the MB dose in the fumigation
chamber. See additional Panel question 9, posed at the mee ting with experts (Transcript, paragraph 10.197), and below
paragraph 8.76.
303 In its answer to an additional Panel question at the second substantive meeting, the United States no longer
seemed to consider testing by product as the only alternative, stating that "it remains the preferred quarantine measure" (US
answers of 24 June 1998, question 1, p.1, emphasis added).
304 See paragraphs 8.76 and 8.77.

"… when establishing or maintaining … phytosanitary measures to achieve the
appropriate level of … phytosanitary protection, Members shall ensure that such
measures are not more trade-restrictive than required to achieve their appropriate level
of … phytosanitary protection, taking into account technical and economic feasibility"
(underlining added).
A footnote to Article 5.6 states the following:
"For purposes of paragraph 6 of Article 5, a measure is not more trade-restrictive than
required unless there is another measure, reasonably available taking into account
technical and economic feasibility, that achieves the appropriate level of …
phytosanitary protection and is significantly less restrictive to trade".
8.71 Article 5.6 must be read in context. We consider, in particular, that the more specific language
of Article 5.6 should be read in light of the more general language in Article 2.2 providing that:
"Members shall ensure that any ... phytosanitary measure is applied only to the extent
necessary to protect ... plant life or health" (underlining added).
8.72 In this dispute, Article 5.6 provides that the varietal testing requirement not be "more trade-
restrictive than required to achieve [Japan's] appropriate level of ... phytosanitary protection, taking into
account technical and economic feasibility". According to the footnote to Article 5.6, the varietal testing
requirement shall be considered to be "more trad e-restrictive than required" if there is another
phytosanitary measure which:
• is "reasonably available taking into account technical and economic feasibility";
• "achieves [Japan's] appropriate level of ... phytosanitary protection"; and
• is "significantly less restrictive to trade" than the varietal testing requirement.
These three elements are cumulative in nature. Only when the United States has raised a presumption,
not sufficiently rebutted by Japan, that all three elements are present, can the varietal testing requirement
be found to be inconsistent with Article 5.6.
3. Alternative measures before the Panel
(a) Testing by product
8.73 The first alternative before the Panel is the one posited by the United States. It involves testing
product-by-product (instead of variety-by-variety).305 Once a variety of a product has been approved, no
further testing at all would be required for any other varieties of that product.
(b) Alternatives derived from the testing of possible differences in sorption
8.74 The scientific experts advising the Panel suggest other alternatives based on the testing of
possible differences in sorption. We deduced thes e alternatives from their written answers to our
questions and, more particularly, from their statements at the expert meeting. Subsequently, at our
second substantive meeting with the parties, bot h parties have expressed their views on these
alternatives. Moreover, before issuing our interim report we sent a draft of those parts addressing these

305 See paragraph 8.65.

alternatives to the experts for their comments.306 We shall, therefore, also examine whether any of these
alternatives meet the three elements under Article 5.6.
8.75 We recall that one of the basic understandings confirmed by the experts advising the Panel is
that if, and to the extent, there are differences between varieties, these would be mainly or even
exclusively related to different levels of sorption of the fruit. 307 Therefore, to control any possible
varietal differences, the experts advising the Panel note that, as an alternative to the varietal testing
requirement, one could either monitor or test the sorption characteristics of the different varieties of
the products at issue.

306 See paragraphs 6.116 and following.
307 See paragraph 8.33 and the references in footnote 261.

(i) Monitoring a predetermined CxT value during commercial treatment
8.76 According to the experts advising the Panel, quarantine efficacy against codling moth could be
achieved by determining a fixed CxT value, i.e., a certain concentration of the fumigant in the chamber
during a certain period of time, to be obtained during quarantine treatment. This CxT value would be so
determined that if a codling moth were fumigated with this concentration during this time, it would die,
irrespective of the host product or variety on whic h it occurs. To obtain this CxT value during
commercial treatment, the MB con centration in the chamber would n eed to be monitored. If the
concentration drops below that required by the CxT value, an additional dose would need to be injected
in the chamber. As long as the CxT value were me t, varietal differences (if there are any, such as
sorption) would not affect quarantine efficacy nor would any other factors.308

308 See Dr. Ducom's answer to Panel question 10:
"The notion of the concentration-time product, or here the CT value, is fundamental in
fumigation. What kills the insect is not only th e dose of gas introduced, but the quantity of gas
inhaled during the entire gas exposure period. The measurement of gas concentrations
throughout fumigation permits one to correlate the efficacy observed not only at the initial
concentration introduced, but also during its evol ution over time, that is to say, the CT value.
This quantity depends on the gas concentration in the chamber whose variation factors are:
- an initial dose introduced into the chamber,
- the load which could increase or decrease the free concentration of gas according to
the sorption of the commodity,
- the sorption of the commodity and of everything present in the chamber,
- eventual leaks.
A CT value is universal once the target stage and the treatment temperature are defined. All the
other factors matter little, even the nature of the commodity, since they are accounted for by the
measurement of gas concentration … The difference [with the current Japanese testing
requirements] is that the CT is definitively acquired and that one could then vary the different
initial parameters. On the contrary, the presen t conditions to impose a recognized effective
treatment consists in fixing initial intangib le draconian conditions (temperature, treatment
length, gas tightness of the chamber, nature of the packing material and load) that would make
any variation impossible. … Finally, I completely agree to admit that the confirmatory test
constitutes a necessary condition to define the quarantine level for a given species of pest. One
can also associate the test to a CT value which is then acquired once and for all … This
objective CT value could become the sole criterion for success in quarantine treatment" (See
also Dr. Ducom's written answers to the Panel's questions, p. 11).
See also Dr. Heather's answer to Panel question 11:
"If the CxT value for a required efficacy against a pest is known then a fumigation treatment that
meets or exceeds that specification can be expected to achieve the quarantine security level
required. This should hold true for all batches of a commodity, including those of differing
varieties, provided that temperature, load and any other relevant requirements are met".
See also the experts' answers to additional Panel question 9 at the meeting with the experts, Transcript, paragraph 10.198 -
10.202. See also Mr. Taylor's closing statement at the meeting with experts, Transcript, paragraph 10.267:
"I would like to say in conclusion that I found on e of the most interesting parts of the meeting
came in question 9 when the Panel asked us if in that statement rather, whether their
understanding of what we were talking about was in fact the case and I think it is clear we are
saying here that if you have the right amount of gas for the right amount of time it will kill the
pest because basically that's what fumigation's all about. It doesn't matter which gas you're
using. If you have the lethal concentration for the required time this will kill the pest and that's
really what we want to try and achieve, so this long and somewhat complicated discussion
about CxT products is in fact very relevant because if we do achieve the desired CxT product in
a commercial treatment we should end up with an effi cacious treatment which s hould satisfy
the requirements for quarantine".

(ii) Determine whether the sorption level of additional varieties differs from that of the already
approved variety
8.77 For the approval of additional varieties of a product for which a treatment for one or more
varieties has already been accepted, Japan currently imposes dose-mortality tests for all varieties and
an on-site confirmatory test – preceded, if required 309, by a large-scale confirmatory test – for one
representative variety. 310 Instead, the experts advising the Panel suggest that Japan could simply
determine the sorption level of each of the additional varieties when treated as required for the already
approved varieties.311 For those additional varieties which do not exceed the sorption level of the
already approved varieties, there would be no need for further testing or confirmation. The
commercial treatment (i.e., a fixed dose-temperature-time relationship, as is the case today) for the
initial variety could then also be approved for the additional variety. For those additional varieties
which do have a higher sorption level, it could then be determined – if need be by means of additional
tests – whether the level of sorption is of sufficient magnitude to reduce the concentration of MB gas
below the level of insect mortality required by Japan. 312 If this were to be the case, a different
commercial treatment for the additional variety could then be imposed.
4. Does any alternative meet all of the elements in Article 5.6?
(a) Testing by product313
8.78 Japan does not contest that testing by product is "reasonably available taking into account
technical and economic feasibility" (i.e., it meets the first element under Article 5.6). We agree.

309 In casu, in the event any of the additional varieties demonstrate, in the dose-mortality tests, significantly lower
disinfestation effects than the already approved varieties.
310 See paragraph 2.24.
311 See answer by Dr. Ducom to Panel question 11:
"If varieties are tested to find the CT value, then no further testing is necessary. The success of
the system implies: (1) that the trials be conducted according to precise guidelines approved by
both parties. In particular, the number of fruits should be quite large in each replicate to
minimize the effects of sampling; (2) that the treatment standard clarify the CT value necessary
to obtain the desired efficacy. This value is th e one found in the confirmatory test, for example
for nectarines, 68 gh/m
3 (Yokoyama, 1990.) The results of these tests are sufficient in
themselves to give confidence in the conformity of the varietal candidate without having to
include the reference variety and insects for efficacy confirmation. This would not bring any
supplementary information".
See also answer by Mr. Taylor to Panel question 11:
"CxT values are used to indicate the fumigant concentration and exposure period required to
achieve a 99% mortality of all development stages of an insect at a particular temperature and
humidity under practical conditions. If these values were obtained for additional varieties and
were found to fall within the range already observed for other varieties it would be difficult to
justify why further testing would be necessary".
See further the answers to additional Panel question 9 at the meeting with the experts, Transcript, paragraph 10.198 - 10.202.
See also the experts' answers to questions by Japan dealing with this alternative approach, Transcript, paragraphs 10.233 -
10.253.
312 The experts advising the Panel noted that the differences in sorption would need to be significant in order to
affect treatment efficacy. See Mr. Taylor's answer to Panel question 9, at paragraph 6.67 and his statement at the meeting
with the experts, Transcript, paragraph 10.82; Dr. Heather's answer to Panel question 10, at paragraph 6.81.
313 See paragraph 8.65.

Technically and economically speaking it is easier to implement testing by product, both for Japan and
the exporting country, than the various tests and procedural steps currently imposed to obtain approval
for additional varieties. Indeed, under the testing by product alternative no further testing at all of
additional varieties would be required.
8.79 Japan does not contest either that testing by pr oduct is "significantly less restrictive to trade"
than the varietal testing requirement (i.e., it meet s the third element under Article 5.6). We agree.
Under the testing by product alternative, market access for additional varieties would be automatic. No
additional testing would be required.
8.80 Japan only contests the remaining element under Article 5.6, namely whether testing by product
would "achieve [Japan's] appropriate level of ... phytosanitary protection".
8.81 Both parties agree that it is up to Japan to determine its appropriate level of phytosanitary
protection with respect to codling moth. We agree since the SPS Agreement (in paragraph 5 of
Annex A) defines the "appropriate level of … phytosa nitary protection" as "[t]he level of protection
deemed appropriate by the Member establishing a ... phytosanitary measure to protect … plant life or
health within its territory"314, in casu, the level deemed appropriate by Japan.
8.82 Both parties also agree on the level of mortality that Japan is seeking with respect to coddling
moth.315 We consider that, for present purposes, this level of mortality can be regarded as Japan's
appropriate level of protection. Japan will lift the import prohibition if it can be replaced by a measure
which achieves the same level of protection as that reached by the import prohibition. With respect to
measures imposing disinfestation, this level is complete mortality in large-scale tests on a minimum of
30,000 codling moths.316 For the testing by product alternative, the question thus becomes whether the
treatment approved for the first variety of a produc t would meet the same level of protection, i.e.,
complete mortality in large-scale tests on a minimum of 30,000 codling moths, with respect to all
other varieties of that product.
8.83 Referring to the opinions we received from the experts advising the Panel, we consider that – to
date and on the basis of the evidence before the Pane l – it is not possible to state with an appropriate
degree of certainty that one and the same treatment would be effective for all varieties of a product. In
the view of the experts advising the Panel, there is no evidence before us which establishes a causal link
between divergent quarantine efficacy and the presence of varietal differences (i.e., evidence which
could justify Japan's varietal testing requirement).
317 However, at least one of the experts advising the
Panel made equally clear that the US alternative of one treatment for all varieties, including those to
be developed in the future, does not, to date, have a scientific basis either. In his answer to Panel
question 16, Dr. Ducom states:
"The arguments put forth by Japan for requiring varietal trials are not based on
scientific data. They are supported by a few experimental data in which varietal
difference exists, in terms of LD50, among a lot of other data in which it does not …
The arguments put forth by the USA are based on a large number of experiments, of
which Japan has thoroughly made use.

314 Emphasis added.
315 See paragraph 8.11.
316 See paragraph 2.23 under "Large-Scale mortality test" and paragraph 8.11. See also answer by Dr. Heather
summarized in paragraph 6.117.
317 See paragraph 8.42.

Varietal difference appears several times, but each time, the confirmatory test has
revealed sufficient efficacy. Extrapolation to all available varieties is no more
scientific than the Japanese's contrary assertion. This sort of extrapolation is
something along the order of intuition. It is unfortunate that there has not been a
research program on the subject in order to try to present some scientific proof".318
8.84 Therefore, after having carefully examined all the evidence before us in light of the opinions we
received from the experts advising the Panel, we ar e not convinced that there is sufficient evidence
before us to find that testing by product would achieve Japan's appropriate level of protection for any of
the products at issue.
(b) Alternatives derived from the testing of possible differences in sorption
(i) Monitoring a predetermined CxT value during commercial treatment319
8.85 The United States recognizes that the process of monitoring a predetermined CxT value could
be less trade-restrictive than the current regime of testing by variety. For the United States, this would
depend on a number of assumptions, including (1) the new treatment methodology would not apply for
varieties already approved for entry to Japan nor for those varieties for which an application is currently
pending; (2) with respect to new commodities, the initial variety on the basis of which the fixed CxT
value would be determined, would not be subject to an on-site confirmatory test; and (3) since the
treatment of apples also involves cold treatment , which is not affected by sorption, the approved
treatment for some varieties of apples should be ex tended to all varieties of apples without further
testing.
8.86 The United States submits that the question of technical and economic feasibility requires more
extensive research and examination. The United States notes that increasing the time and/or dose of an
MB treatment to achieve a particular CxT value could result in residues unacceptable for reasons of
human health and/or conflict with applicable US environmental laws and regulations. 320 The United
States also points out that in order to conduct precise measurements of CxT values, gas chromatographs
would be required. However, for commercial applications of MB a fumiscope (which is less precise) is
much more commonly available. Fumiscopes are also significantly less expensive and simpler to
operate than gas chromatographs. The United States further argues that since monitoring of each
treatment would be required, treatments would become more labour intensive than current applications
of accepted treatments.
8.87 Japan submits that it does not have information on whether the process of monitoring a
predetermined CxT value would be technically or economically feasible for exporting countries.
Consequently, Japan is not certain if the process would be less trade-restrictive than the present regime.

318 Dr. Ducom's written answers, pp. 10-11, underlining adde d. At the meeting with the experts, Japan referred to
this statement, noting that Dr. Ducom seems to concur "that there is no valid scientific ground to conclude that a treatment
established for a particular variety by confirmatory tests would be efficacious for any additional variety" (Transcript, paragraph
10.92). Dr. Ducom replied as follows: " Yes that is correct. I mean I cannot see any more scientific basis on the Japanese
side than on the USA's side to say [that each] variety must be carefully treated … or for one we can have all varieties. I hop e
you understand. In my opinion it is not scientific to say that one variety is equal to all others …" (Transcript, paragraph
10.93).
319 This alternative is outlined in paragraph 8.76.
320 In answering an additional Panel question, the parties referred to the Montreal Protocol on Substances that
Deplete the Ozone Layer which mandates the phasing-out of MB in developed countries by 2005 (Article 2H). However,
they also noted that the use of MB for quarantine and preshipment application is exempted from this phasing-out schedule
(Article 2H:6). According to the United States, the production and importation of MB is to be phased-out in the United
States by 1 January 2001. The United States noted that its administration has expressed a willingness to consult with the US
Congress on changes to US law if alternatives do not exist for control of key pests as the 2001 phase-out date approaches.

8.88 When we asked the experts advising the Panel whether in their expert opinion the process
would be technically and economically feasible, Dr. Ducom answered "yes".321 Mr. Taylor stated that it
is technically feasible, but reserved his judgment on the economic feasibility, adding that it is probably
economically feasible.322 Dr. Heather deferred to the other two experts.323
8.89 Referring to the arguments made by the parties 324, the evidence before us and the opinions of
the experts advising the Panel, we are of the view that, to date, there is not enough evidence before the
Panel to enable us to find that the process of monitoring a predetermined CxT value would be
technically and economically feasible and significantly less restrictive to trade than the current regime
(i.e., fulfils the first and third element under Article 5.6).
8.90 We note, however, that according to the opinions of the experts advising the Panel 325, this
alternative would not only guarantee, to a high probability, quarantine efficacy irrespective of possible
varietal differences, but also irrespective of any other variables such as crop-to-crop and year-to-year
differences within the same variety, i.e., differences which are not taken into account under the
current regime.326
(ii) Determine whether the sorption level of additional varieties differs from that of the already
approved variety327
8.91 Japan does not contest that determining the sorption level of additional varieties, and comparing
it with the sorption level of an approved variety, is "reasonably available taking into account technical
and economic feasibility". The United States has given views which are consistent with this.328

321 See Transcript, paragraph 10.198.
322 Mr. Taylor stated:
"Yes I have to agree with Dr. Ducom. In many cases of course of fumigation of other
situations, such as the treatment of flour mills, there is regular monitoring, as we call it, of the
fumigant level. It may be necessary to increase the fumigant concentration by adding more
fumigant for example, because of some factor, maybe leakage, etc., so I mean this is certainly
something that can be done, and is done, and if this type of technology was employed whereby
the concentration is monitored regularly and it is found to reach the required level, in other
words, you will end up with the CxT product value that you have said is necessary, then this
will be an effective treatment and I mean so this is technically feasible. I will reserve judgment
on the economic feasibility to those that know more about the topic than myself. But probably
it is. I would think it to be probably technically and economically feasible." (Transcript,
paragraph 10.200).
323 Dr. Heather stated:
"I'd have to defer to my colleagues who know more, who have more practical experience of
fumigation, but I am aware that grain in my home State is controlled by the use of a CxT
approach rather than an outright dose" (Transcript, paragraph 10.202).
324 See paragraphs 8.85-8.87.
325 See paragraph 8.76 and footnote 308.
326 See, for example, the statement by Dr. Ducom that
"[a] CT value is universal once the target stage and the treatment temperature are defined. All
the other factors matter little, even the nature of the commodity, since they are accounted for by
the measurement of gas concentration" (Dr. Ducom's answer to Panel question 10).
327 This alternative is outlined in paragraph 8.77.

8.92 Under this alternative, the initial variety of a product would be subject to the existing testing
requirements; a certain treatment (including a fixed exposure time, dose and temperature) would then
be determined. For additional varieties there would only be a need to determine to what extent, if any,
the sorption characteristics of the additional varieties differ from those already approved. Such
determination would only require a one-time test for each additional variety. According to the experts
advising the Panel, this test would be a relatively easy one; at least easier to conduct than the currently
required dose-mortality test since it involves neither codling moths nor LD trials. In this respect, Dr.
Ducom notes the following:
"I just advise something about sorption. Levels are important for varieties but that
means no insects, no LD
50 trials to show that sorption is different. I mean we don't
need any insects and any dose mortality tests to show that sorption is different and it
makes very different, it's very easy, it's easier to run a sorption test than the dose
mortality test. That's an important point in practice".329
Mr. Taylor, in turn, states:
"… there are quite well known methods by which accurate levels of sorption can be
tested … certainly techniques such as these have been conducted over many years so
there should be no problem in actually conducting these trials. As Dr. Ducom said, to
determine the sorption of fumigant would not involve insects in these test, just the gas
and the commodity, and from these tests to see to what extent there is a difference
between varieties as between commodities, and to determine just to what extent this is
an important factor and whether the level of sorption is very high or very little
difference exists between the two".
330
8.93 If, as a result of sorption tests, the sorption level of the additional variety is not higher than
the sorption level of the initial variety, the same treatment can be applied for both varieties, without
further testing or confirmation. If the sorption level of the additional variety is higher than that of the
initial variety, it could then be determined – if need be by means of additional tests – whether the
level of sorption is of sufficient magnitude to reduce the concentration of MB gas below the level of
insect mortality required by Japan.
331 If this were to be the case, a different commercial treatment for
the additional variety could then be imposed.
8.94 On these grounds, we consider that the process of determining the sorption level of additional
varieties can be presumed to be "reasonably available taking into account technical and economic
feasibility" (i.e., to meet the first element under Article 5.6).

328 The United States did not specifically address the tec hnical and economic feasibility of this third alternative.
However, the Panel considered all other US arguments in this respect. None of these arguments go against the idea that this
third alternative would be technically and economically feasible.
329 Transcript, paragraph 10.142. See also Dr. Ducom's statement, Transcript, paragraph 10.188.
330 Transcript, paragraph 10.192. See also Dr. Ducom's written answers, p. 8 ("Research on the CT per variety is an
operation which could be rapidly conducted, since only the variety of fruit to be tested is used. Fumigation only lasts two
hours and the result is known immediately") and p. 11 ("For the USA, this system is quick and low-cost").
331 The experts advising the Panel noted that the differences in sorption would need to be significant in order to
affect treatment efficacy. See Mr. Taylor's answer to Panel question 9, at paragraph 6.67 and his statement at the meeting
with the experts, Transcript, paragraph 10.82; Dr. Heather's answer to Panel question 10, at paragraph 6.81;

8.95 Japan does not contest that the process of determining the sorption level of additional varieties
is "significantly less restrictive to trade" than the varietal testing requirement. The United States has
given views which are consistent with this.332
8.96 Under this alternative, testing for most (if not all) additional varieties would be limited to a
sorption test. If the sorption level is not higher than that of already approved varieties, no further
testing or confirmation would be required. In that event, market access would be obtained
significantly more easily than under the current regime. If the sorption level is higher than that of
already approved varieties, further examination and, if need be, additional testing could then be
required. In that case, market access would be obtained in circumstances no more difficult than under
the current regime.
8.97 On these grounds, we consider that the process of determining the sorption level of additional
varieties can be presumed to be "significantly less restrictive to trade" than the varietal testing
requirement (i.e., to meet the third element under Article 5.6).
8.98 Japan has not accepted that the process of determining the sorption level of additional
varieties would achieve its appropriate level of protection. The United States, on the other hand,
suggests that this process would meet Japan's appropriate level of protection".333
8.99 We recall that it is for Japan to determine its level of phytosanitary protection and that, in this
case, the level of mortality sought by Japan for codling moth is not in dispute. 334 Japan's level of
mortality is complete mortality in large-scale tests on a minimum of 30,000 codling moths.335 For the
alternative of determining the sorption level of additional varieties, the question thus becomes
whether the treatment approved for the initial variety of a product would meet the same level of
protection, i.e., complete mortality in large-scale tests on a minimum of 30,000 codling moths, with
respect to all other varieties of that product which have the same (or lower) sorption levels as the
initial variety.
8.100 According to the experts advising the Panel, this would be the case. 336 Dr. Ducom notes, for
example:
"If varieties are tested to find the CT value [an indication of the amount of fumigant
sorbed], then no further testing is necessary … The results of these tests are sufficient
in themselves to give confidence in the conformity of the varietal candidate without
having to include the reference variety and insects for efficacy confirmation".337

332 The United States did not specifically address whether this third alternative is significantly less trade-restrictive.
However, the Panel considered all other US arguments in this respect. None of these arguments go against the idea that this
third alternative would be significantly less trade-restrictive.
333 The United States did not specifically address whether this third alternative would meet Japan's appropriate
level of protection. However, the United States submits that testing by product would meet Japan's level of protection.
Since this third alternative is more stringent than testing by product, it can thus be presumed that the US view on this
alternative would be that it a fortiori meets Japan's level of protection.
334 See paragraphs 8.81-8.82.
335 See paragraph 2.23 under "Large-Scale mortality test" and paragraph 8.11. See also answer by Dr. Heather
summarized in paragraph 6.117.
336 See the expert opinions referred to in footnote 311.
337 Dr. Ducom's written answer to Panel question 11, underlining added. See also Dr. Ducom's written answers to
the Panel's question, p. 11: "For Japan, [the alternative] is acceptable in terms of efficacy". Dr. Ducom then refers to a
statement by Japan itself according to which "the CT value, a known indicator to control the degree of efficacy of the
treatment, will vary as well depending on the variety of the fruit" (First submission of Japan, paragraph 78).

Mr. Taylor, in turn, states:
"CxT values are used to indicate the fumigant concentration and exposure period
required to achieve a 99% mortality of all development stages of an insect at a
particular temperature and humidity under practical conditions. If these values were
obtained for additional varieties and were found to fall within the range already
observed for other varieties it would be diff icult to justify why further testing would
be necessary".338
8.101 On the basis of the evidence before the Panel and the views we received from the experts
advising the Panel, we thus consider that it can be presumed that the process of determining the
sorption levels of additional varieties – so as to ensure that these levels do not differ in a way which
would affect the efficacy of MB treatment – "achieves [Japan's] appropriate level of … phytosanitary
protection" (i.e., meets the second element under Article 5.6). We also consider that Japan has not been
able to rebut this presumption.
(c) The Panel's conclusion under Article 5.6
8.102 Irrespective of whether Article 2.2 is violated in this case, we offer the following conclusion
with respect to Article 5.6. Indeed, even if we we re to have found that Japan's measure is maintained
with sufficient scientific evid ence in accordance with Article 2.2, we would then be called upon to
examine whether the measure is consistent with Article 5.6.
8.103 We have considered above that – on the basis of the evidence before the Panel and the
opinions of the experts advising the Panel – it can be presumed that an alternative measure exists (i.e.,
determining the sorption level of additional varieties as described in paragraphs 8.76 and 8.91 and
following) which would meet all of the elements under Article 5.6. 339 In so doing, we are not
endorsing this or any other specific alternative measure as the measure to be put in place by Japan.
8.104 We thus conclude that the varietal testing re quirement maintained by Japan is more trade-
restrictive than required within the meaning of Ar ticle 5.6. For the same reasons as those outlined in
paragraphs 8.44 and 8.45, on the basis of the evidence before us, we only make this finding with respect
to apples, cherries, nectarines and walnuts.
H. TRANSPARENCY OF PHYTOSANITARY MEASURES (ARTICLE 7 AND ANNEX B OF THE SPS
AGREEMENT)
1. Arguments by the parties
8.105 The United States also claims that the varietal testing requirement has not been published,
making it inconsistent with Article 7 of the SPS Agreement.
8.106 Japan does not contest that the varietal testing requirement is in effect and applied. Japan
acknowledges, moreover, that it has not been published. Japan argues, however, that the guidelines
developed by the MAFF concerning confirmation of efficacy of a disinfestation treatment have been
distributed to foreign plant quarantine authorities for the purpose of transparency. Japan stresses,
moreover, that these guidelines are available to any interested foreign government through Japan's

338 Mr. Taylor's written answer to Panel question 11, underlining added.
339 See paragraphs 8.94, 8.97 and 8.101.

Enquiry Point in accordance with paragraph 3 (b) of Annex B to the SPS Agreement and that anyone
who wants to know more about approved products can refer to the MAFF notifications published in
the Official Gazette or contact MAFF itself. Japan further contends that the guidelines do not
constitute enforceable phytosanitary "regulations" under paragraph 1 of Annex B. According to
Japan, they are only a model and are not mandatory since exporting countries may choose to
demonstrate efficacy of treatment by other means. Finally, according to Japan, these guidelines are
not generally published because they are a highly technical document addressed to foreign plant
quarantine authorities.
8.107 In response, the United States submits that irrespective of the informal process by which US
scientists, in consultation with Japan, have devised procedures to test by variety, the fact remains that
the varietal testing requirement itself should be published. According to the United States, the net
result is that absent such publication, an exporter has no way to discern what is necessary to move a
product from the prohibited list to a list approved by Japan for entry.
2. Evaluation by the Panel
8.108 We note that Article 7 provides in relevant part:
"Members ... shall provide information on their ... phytosanitary measures in
accordance with the provisions of Annex B".
Paragraph 1 of Annex B, in turn, states that:
"Members shall ensure that all ... phytosanitary regulations which have been adopted
are published promptly in such a manner as to enable interested Members to become
acquainted with them".
A footnote to this paragraph specifies that the "phytosanitary regulations" referred to are:
"phytosanitary measures such as laws, decrees or ordinances which are applicable
generally".
8.109 Therefore, in our view, for a measure to be subject to the publication requirement in Annex B,
three conditions apply: (1) the measure "[has] been adopted"
340; (2) the measure is a "phytosanitary
regulation"341, namely a phytosanitary measure such as a law, decree or ordinance 342, which is (3)
"applicable generally".343
8.110 The fact that the varietal testing requirement challenged by the United States "[has] been
adopted" and is "applicable generally" is not in dispute. We only need to examine whether this
requirement is a "phytosanitary regulation" in the sense of paragraph 1 of Annex B.
8.111 Even though the varietal testing requirement is not mandatory – in that exporting countries
can demonstrate quarantine efficiency by other means – in our view, it does constitute a
"phytosanitary regulation" subject to the publication requirement in Annex B. The footnote to
paragraph 1 of Annex B refers in general terms to "phytosanitary measures such as laws, decrees or

340 See paragraph 1 of Annex B of the SPS Agreement.
341 Ibid.
342 See footnote to paragraph 1 of Annex B.
343 Ibid.

ordinances".344 Nowhere does the wording of this paragraph require such measures to be mandatory
or legally enforceable. Moreover, Paragraph 1 of Annex A to the SPS Agreement makes clear that
"phytosanitary measures include all relevant laws, decrees, regulations, requirements and procedures".
It does not, in turn, require that such measures be mandatory or legally enforceable. The
interpretation that measures need not be mandatory to be subject to WTO disciplines is confirmed by
the context of the relevant SPS provisions, a context which includes provisions of other WTO
agreements and the way these provisions define "measure", "requirement" or "restriction"
345, as
interpreted in GATT and WTO jurisprudence. 346 This context indicates that a non-mandatory
government measure is also subject to WTO provisions in the event compliance with this measure is
necessary to obtain an advantage from the government or, in other words, if sufficient incentives or
disincentives exist for that measure to be abided by.
8.112 We consider that in this case the varietal testing requirement, as set out in the "Experimental
Guide for Cultivar Comparison Test on Insect Mortality – Fumigation" (hereafter referred to as "the
guidelines"), does provide sufficient incentives for it to take effect. Indeed, if an exporting country
abides by the guidelines, its request for entry of a certain variety of a product will be granted. If an
exporting country accepts the varietal testing require ment and follows the guidelines, it will do so in
order to obtain an advantage from the government. We thus consider that the varietal testing
requirement is a phytosanitary regulation in the sense of paragraph 1 of Annex B.
8.113 We note, moreover, that even though Japan submits that the guidelines are only a test model and
that exporting governments may choose to demonstrate efficacy of treatment by other means, Japan
asserts that so far no exporting government ever proposed such other means 347 and that Japan,
accordingly, never accepted any alternative means.

344 In accordance with Article 3.2 of the DSU and established WTO jurisprudence, we shall interpret these terms in
paragraph 1 of Annex A in accordance with the interpretative rules of the 1969 Vienna Convention on the Law of Treaties
("Vienna Convention"), in particular Article 31 thereof which provides in relevant part as follows: "1. A treaty shall be
interpreted in good faith in accordance with the ordinary meaning to be given to the terms of the treaty in their context and in
light of its object and purpose".
345 For example, the Illustrative List of Trade-Related Investment Measures ("TRIMs") contained in the Annex to
the Agreement on TRIMs indicates that TRIMs inconsistent w ith Articles III:4 and XI:1 of the GATT include those which
are "mandatory or enforceable under domestic law or under administrative rulings, or compliance with which is necessary to
obtain an advantage" (emphasis added).
346 Recently, for example, the panel on Japan – Measures Affecting Consum er Photographic Film and Paper
(adopted on 22 April 1998, WT/DS44/R), addressing a claim of non-violation nullification and impairment under Article
XXIII:1(b) of the GATT, stated the following (at paragraph 10.49):
"a government policy or action need not necessarily have a substantially binding or compulsory
nature for it to entail a likelihood of compliance by private actors in a way so as to nullify or
impair legitimately expected benefits within the purview of Article XXIII:1(b). Indeed, it is
clear that non-binding actions, which include sufficient incentives or disincentives for private
parties to act in a particular manner, can potentially have adverse effects on competitive
conditions of market access".
See also the panel report on Japan – Trade in Semi-Conductors (adopted on 4 May 1988, BISD 35 S/116), where
the panel found (at paragraph 109) that although measures are not mandatory, they could be considered as "restrictions"
subject to Article XI:1 of the GATT in the event "sufficient incentives or disincentives existed for non-mandatory measures
to take effect". Similarly, the panel on EEC – Regulation on Imports of Parts and Components (adopted on 16 May 1990,
BISD 37S/132) considered (at paragraph 5.21) that the term "l aws, regulations or requirements" contained in Article III:4 of
the GATT included requirements "which an enterprise voluntarily accepts in order to obtain an advantage from the
government".
347 The United States, however, asserts that it did propose alternatives, including 100 per cent inspection of certain
apples and inspection for certification of cherries (in both instances without fumigation) and the use of a systems approach
for nectarines, but that Japan rejected these alternatives.

8.114 We thus find that the varietal testing requirement meets all three conditions for a measure to
be subject to the publication requirement in paragraph 1 of Annex B. The requirement thus needs to
be "published promptly in such a manner as to en able interested Members to become acquainted with
them".
8.115 Japan acknowledges that it has not published the varietal testing requirement. The fact that
Japan distributed the guidelines to foreign plant quarantine authorities does not mitigate the lack of
publication. In our view, distribution to a limited number of addressees and MAFF's general
availability to answer any queries, does not equal prompt publication which enables interested
Members to become acquainted with the varietal testing requirement. The publication by MAFF of the
protocols relating to approved products does not ensure publication of the varietal testing requirement
itself. It only informs Members of products which have met this requirement. Moreover, we do not
consider that the highly technical nature of the varietal testing requirement can excuse Japan from
publishing it.
3. The Panel's conclusion under Article 7
8.116 On these grounds
348 we conclude that Japan, by not having published the varietal testing
requirement, acts inconsistently with its obligations under paragraph 1 of Annex B of the SPS
Agreement and, for that reason, with its obligations contained in Article 7 of that Agreement. Since
Japan has not published the measure at issue with respect to any of the products falling within our
mandate, our finding applies to all of these products.
I. OBLIGATIONS WITH RESPECT TO CONTROL , INSPECTION AND APPROVAL PROCEDURES
(ARTICLE 8 AND ANNEX C OF THE SPS AGREEMENT)
8.117 Given that we have found earlier that the varietal testing requirement is inconsistent with the
requirements of Articles 2.2 349, 5.6 350 and 7 351 of the SPS Agreement, we see no need to further
examine whether it is also inconsistent with Article 8, referring to Annex C, of that Agreement.
J. CONCLUDING REMARK
8.118 In footnote 320, we noted that the parties to this dispute referred to the fact that the substance
methyl bromide – used in the quarantine treatments at issue here – needs to be phased-out in
accordance with the Montreal Protocol on Substances that Deplete the Ozone Layer ("Montreal
Protocol"). However, the parties to this dispute also noted that Article 2H:6 of the Montreal Protocol
exempts the use of Methyl Bromide for quarantine and preshipment application from this phasing-out
schedule.
8.119 Without embarking on an examination of the Montreal Protocol, we do want to stress that
nothing in this report should be read in a way which would affect the rights and obligations of WTO
Members party to the Montreal Protocol.

348 See paragraphs 8.108 - 8.115.
349 See paragraph 8.61.
350 See paragraph 8.104.
351 See paragraph 8.116.

IX. CONCLUSIONS
9.1 In light of the findings above, we reach the conclusion that Japan
(i) by maintaining the varietal testing requirement in dispute with respect to apples,
cherries, nectarines and walnuts, acts inconsistently with its obligation under
Article 2.2 of the SPS Agreement not to maintain phytosanitary measures "without
sufficient scientific evidence, except as provided for in paragraph 7 of Article 5"; and
(ii) by maintaining the varietal testing requirement in dispute with respect to apples,
cherries, nectarines and walnuts, acts inconsistently with its obligation in Article 5.6
of the SPS Agreement to "ensure that [its phytosanitary] measures are not more trade-
restrictive than required to achieve [Japan's] appropriate level of … phytosanitary
protection, taking into account technical and economic feasibility"; and
(iii) by not having published the varietal testing requirement in dispute with respect to any
of the products at issue, acts inconsistently with its obligations under paragraph 1 of
Annex B of the SPS Agreement and, for that reason, with its obligations contained in
Article 7 of that Agreement.
9.2 Since Article 3.8 of the DSU provides that "[i]n cases where there is an infringement of the
obligations assumed under a covered agreement [including the SPS Agreement], the action is considered
prima facie to constitute a case of nullification or impairment", we conclude that to the extent Japan has
acted inconsistently with the SPS Agreement it has nullified or impaired the benefits accruing to the
United States under the SPS Agreement.
9.3 We recommend that the Dispute Settlement Body request Japan to bring its measure in dispute
into conformity with its obligations under the SPS Agreement.

X. ANNEX A - TRANSCRIPT OF THE JOINT MEETING WITH EXPERTS
Chairman
10.1 [introductory statement by the Chairman] … with that introduction I would first invite all the
participants to introduce themselves and then I would suggest that we start with the opening
comments of the experts. Dr. Ducom, Dr. Heather a nd Mr. Taylor in that order. May I first ask that
the experts present themselves?
Dr. Ducom
10.2 Mr. Chairman, thank you. First of all I am French and my mother-tongue is French, is not
English, that's why my brief statement will be short. Officially I belong to the French Ministry of
Agriculture, but in this session I am not mandated by my Ministry. I am just a private expert here.
Some highlights - First of all, pardon? [Chairman interrupts]
Chairman
10.3 Thank you. If there is need for translation we have here bilingual persons which can assist
you if necessary.
Dr. Ducom
10.4 My problem is that I can understand but to express myself is much more difficult.
Chairman
10.5 And of course you are very correct, all the experts are in their personal capacity and do not
represent an institution or country. Ok, Dr. Heather?
Dr. Heather
10.6 I am Neil Heather. I come from Brisbane, Australia where prior to ceasing duty with the
Queensland State Department of Primary Industries, I was research leader of what we call the Market
Access Quarantine Group, responsible for developing fruit-fly treatments for access to export markets
from Australia, i.e., quarantine disinfestation treatments. I am currently affiliated with the University
of Queensland at Gatton College where I am termed an Honorary Research Consultant so I have no
organisational responsibilities of any kind.
Chairman
10.7 Thank you. And Mr. Taylor?
Mr. Taylor
10.8 Thank you Mr Chairman. Good morning Ladies and Gentlemen. I am very happy to be here
and pleased to have been invited to this Panel and to visit Geneva again. I am employed at the
Natural Resources Institute in the United Kingdom which until 1996 was a government agency but
since that time we've been sold off and we are now part of the University of Greenwich. Much of our
work continues in the same manner and we are largely funded by the UK government although I am
here representing myself, as I do, on the methyl bromide technical options committee. So I stand as
an individual. I spend most of my time working overseas in developing countries on pest control
activities, particularly with fumigation. Thank you.

Chairman
10.9 Thank you Mr. Taylor. I now turn to the United States delegation.
Mr. Brinza
10.10 Thank you Mr. Chairman. My name is Dan Brinza from the United States. I will ask other
members of the US delegation to take the mike very briefly to introduce themselves, starting with the
head of delegation.
United States (Mr. Hirsh)
10.11 Good morning Mr. Chairman. My name is Bruce Hirsh and I am an Assistant General
Counsel with the Office of the United States Trade Representative.
Mr. Bonner
10.12 Good morning. Peter Bonner, US Department of Agriculture.
Mr. Vick
10.13 My name is Ken Vick, United States Department of Agriculture.
Mr. Thaw
10.14 I'm John Thaw with Plant Protection and Quarantine, Department of Agriculture.
Mr. Leesch
10.15 I'm Jim Leesch. I'm with the US Department of Agriculture, Agricultural Research Service.
Mr. Fedchock
10.16 Craig Fedchock with US Department of Agriculture, APHIS.
Ms. Roberts
10.17 I'm Donna Roberts with the US Department of Agriculture here at the Mission in Geneva.
Ms. Erickson
10.18 Audrae Erickson, US Trade Representatives Office, Washington DC.
Chairman
10.19 Thank you. I now return to the Japanese delegation please.
Mr. Yokota
10.20 Thank you Mr. Chairman. My name is Jun Yoko ta. I'm the Deputy Director-General of the
Economic Affairs Bureau, the Ministry of Foreign A ffairs. I would like to turn to my colleagues to
present themselves.

Mr. Kato
10.21 My name is Takashi Kato. I'm from the Ministry of Agriculture, Forestry and Fisheries and
Deputy Director-General in the Agricultural Production Bureau. Thank you.
Mr. Nakakita
10.22 My name is Hiroshi Nakakita from National Food Research Institute, studying about how to
control stored product insect.
Mr. Kawakami
10.23 My name is Fusao Kawakami. I work in the Research Division of Yokohama Plant
Quarantine Station. For many years I engage in the development of the disinfestation methods for
quarantine so I [was involved in] research data submitted from foreign countries.
Mr. Sato
10.24 My name is Kimihiko Sato, Tokyo University of Agriculture and Technology.
Mr. Sakai
10.25 My name is Masaki Sakai, Agriculture Counsellor, Embassy of Japan, Washington DC.
Mr. Saito
10.26 My name is Noboru Saito. I am working for Plant Production Division, Ministry of
Agriculture, Forestry and Fisheries. Thank you.
Mr. Sanatani
10.27 My name is Sanatani. I am from Ministry of Agriculture in Tokyo.
Ms. Hirota
10.28 My name is Mitue Hirota. I come from the Ministry of Foreign Affairs.
Mr. Yokoi
10.29 My name is Yukio Yokoi, Plant Protection Division, Ministry of Agriculture, Forestry and
Fisheries.
Mr. Shiragaki
10.30 My name is Tatsunori Shiragaki from the Ministry of Agriculture.
Mr. Motai
10.31 My name is Futao Motai from the Ministry of Foreign Affairs, Japan.
Mr. Yamashita
10.32 My name is Masayuki Yamashita. I'm with the Japanese Mission here in Geneva.

Mr. Nirei
10.33 I am Hideo Nirei from the Authority Bureau of Ministry of Foreign Affairs.
Mr. Chujo
10.34 Kazuo Chujo, Ministry of Foreign Affairs.
Mr. Ito
10.35 My name is Koichi Ito, Japanese Mission in Geneva. Thank you.
Chairman
10.36 Thank you for these introductions. I think that we now can start our discussion according to
the procedures I proposed, and that means that I will start by giving the floor one by one to our
experts for any general introductory remarks they believe are appropriate.
10.37 So first, in alphabetical order, Dr. Ducom, you have the floor.
Dr. Ducom
10.38 Thank you Mr. Chairman. I have just five remarks on the question and my answers, mainly
on the questions.
10.39 First of all, the questions of the Panel are relevant but often there is no clear response to give
because we miss data on the exact subject on variety by variety testing. Second point, it seems that
both sides want to keep their habits; the arguments can be seen as black or white and each party has
found, for example in their answers to the questions, arguments against each other in the same paper.
The third point is that the scientific facts given by Japan are maybe too narrow. I mean, for example,
when they give some differences between varieties the confidence limit is not a biological fact, it is a
statistical fact. I mean, biologically speaking, the difference does not matter … just one per cent
makes, statistically speaking, there is a significant difference while biologically speaking there is no
difference. We have examples of that. The fourth point. For the USA position one variety for all is
maybe uncomfortable because biology or physiology is sometimes surprising. That may be the
problem. And the last point is that maybe that the concept of CxT product is not used enough in this
dispute, or in this matter.
Chairman
10.40 Thank you Dr. Ducom. Then I turn to Dr. Heather.
Dr. Heather
10.41 Thank you. As with Dr. Ducom I have had some difficulty through not seeing all of the
working data but had I seen it, there would not have been sufficient time to perhaps look at it in the
detail that's required. Just to perhaps go through your original questions, if I may. The concepts: I
think in my view, the most important part here is the interpretation put on the LD values, the LD 50
value for example. This is not a precise numerical measure and of necessity it has had to be used in a
rather less precise way than it would otherwise be. It is not a direct measurement on the insect, it is a
measurement on the insect where it is influenced by the fruit in the chambers so it is not a precise
measurement. In fact, if you look at an LD value it's easy to take one figure but realistically you
should be looking at what we call the confidence limits or the fiducial limits and these are ranges
within which that value falls and perhaps would lead to a better understanding if we thought of it in
that way. As you recall, because the quarantine treatments are not measured at the median dose or the

LD50 dose but at the extreme dose, these limits become very wide and it is not wise to take arithmetic
cognizance. You must take into account the truest statistical interpretation of these figures. Sorry I
have talked too much on that but I think it is a very important thing; that precision is easily
misplaced.
10.42 The confirmatory tests, I have every confid ence in and I think that's fairly well accepted
throughout [by all parties]. There's been some consideration about the higher susceptibility of (a
question asked by Japan) on the higher susceptibility of a commodity for a range of reasons which are
outside of the direct interaction between the frui t and the treatment. But here we can have such
instances as a late variety of fruit compared to an early variety of fruit; there will be many more
insects in the place of origin of the late maturing va riety than there were in the beginning. This is the
type of background that I wish that comment to be interpreted against.
10.43 The sorption I would like to leave to my colleagues who are rather more wise in the theory of
the behaviour of gases and fumigants than I, although I have used them to an extent where I've some
understanding of them. The statistical analysis, or the CxT product value, by the way, is a much more
precise measure than a LD value, much more precise, because it is a physical measurement rather than
a biological one. There's been some misunderstanding perhaps about Tukey's multiple range test. It
is simply a less sensitive type of analysis which means that it should be more reliable, but could I say
that for statistically demonstrated differences, these must always be viewed against the background of
the biological conditions which give rise to them. What is biologically unlikely, but statistically
shown, must be viewed with some reserve. Biological creditability is just as important as statistical
demonstration of differences. I think that they were the main points that would arise. Could I ask Mr.
Chairman do you wish us to address the additional questions? Thank you.
Chairman
10.44 Yes, as you know the Panel has distributed yesterday evening some additional questions. My
intention is to raise them after we have discussed the questions raised by the United States and the
Japan, and of course I will raise only those of them which have not already been covered by the
questions of United States or Japan. So the order will be the questions by the United States, the
questions by Japan, the questions by Panel. Ok. Then Mr. Taylor?
Mr. Taylor
10.45 Thank you Mr. Chairman. I don't have too much to say at this particular time. I think one of
the things that we must accept is that temperature is very, very important in fumigation and also
particularly in the case of methyl bromide sorption is of overwhelming interest and knowledge of
what is happening is terribly important.
10.46 If I might just digress very, very briefly - there is another fumigant, phosphine, which is used
for durable commodities. There is little or no sorption of phosphine and, therefore, the dosage rates
really don't vary much at all for different commodities. It may be rather an over simplification but it
could be said that, compared do methyl bromide, there is just one dosage rate for phosphine. Coming
back of course to the subject matter of methyl bromide, we do have an overwhelming difference in as
much as there is a lot of sorption by commodities, and in fact, in durable commodities which I have to
refer to because they are my main area of experience, certainly in the original schedules drawn up for
commodity fumigation a commodity dosage was specified. So in fact great importance was taken of
the particular commodity in deciding what the application rate should be because there was such a
large difference between commodities that you had to define the commodity and then decide what the
dose should be based on that commodity, let alone on what insect you were controlling. So in brief,
the fact that there may be a high fat or oil content in which the methyl bromide would dissolve meant
that a lot of the gas was lost, so certainly the sorption factor is very important and so important that
this created differences in terms of dosage rates used. Now whether or not these differences exist in
fruit is something which I am certainly not confid ent to comment on, but the differences certainly, if

they were there, would be sufficient to cause different dosage rates to be required and therefore testing
programmes to be necessary. But if the differences between varieties are so small that there is little or
no sorption, then it seems to me that varietal testing is perhaps not something which needs to be taken
into consideration, particularly if tests have shown, for example, that the chemical composition of the
fruit varieties do not vary very much. Because again, going back to what I said about the durable
commodities, certainly the differences there are very significant and are so significant that dosage
rates are specified for different commodities but not of course for different varieties, for example, of
wheat.
10.47 One other point, I would just like to reiterate what Dr. Heather said. LD
50 values are very
useful if you are comparing insects, for example, for levels of resistance. But I don't think in this case
we're looking to define dosage rates even for - shall we say, non-quarantine treatments, we would
want to use LD50 - we'd want to use higher levels of control such as, well, certainly the LD 99 or LD99.9.
And therefore the LD50 I don't think is at all relevant in this situation.
10.48 So I would just say then that sorption seems to me to be something that we need to know
more about. If it can be shown that the levels of sorption are such that they are significant enough to
remove the fumigant to an extent that it is going to raise some doubt as to the efficacy of the
treatment, then of course we could say that varietal testing was necessary. But unless we can show
that it seems to me that the need to test by variety does still need to be established. Thank you Mr.
Chairman.
Chairman
10.49 Thank you Mr. Taylor. I now turn to the United States delegation and you have the floor.
United States (Mr. Hirsh)
10.50 Thank you very much Mr. Chairman. First of all, on behalf of the US delegation I would like
to thank the experts for agreeing to serve and for their very helpful comments today and their
responses. We very much appreciate your taking the time to be with us today. With your permission,
Mr. Chairman, I would like to take about five minutes just to consult with the delegation to consider
in light of the initial comments by the experts whether we want to ask certain questions, if that's
permissible?
[break]
United States (Mr. Hirsh)
10.51 Thank you Mr. Chairman. We just have a few brief questions. All of the questions - for all
the questions, any of the experts are welcome to respond. We've noted in some instances that one or
more of the experts have focused on the particular question we directed initially to them.
10.52 The first question we have is a request for clarification from Mr. Taylor on his introductory
comments. With respect to the differences in so rption that you have noted for durable commodities
we want to just clarify that those differences have been observed on a commodity by commodity
basis.

Mr. Taylor
10.53 Yes, certainly, on a commodity by commodity basis, yes, the differences are there although
some commodities are so similar that certainly for practical purposes commodities are often grouped
together. As I say, for practical purposes certain cereals may be grouped together and then other
different types of commodities - so that there may be five or six different groups, yes.
United States (Mr. Hirsh)
10.54 But the observed differences have not been on a variety basis but on a commodity basis?
Mr. Taylor
10.55 You're exactly right, yes. And in fact, I've never even heard anybody raise the subject of
varieties of rice or wheat or maize requiring to be examined in as much as there might be some
differences. So, no, it is merely on a commodity by commodity basis.
United States (Mr. Hirsh)
10.56 Thank you. Also, one or two enquires with regard to the differences in sorption that you have
noticed between commodities, durable commodities. Have the magnitude of those differences been
obvious?
Mr. Taylor
10.57 Oh yes, yes certainly. The work that was done probably many, many years ago, perhaps even
I think before I became involved in this topic, I think maybe even in the 1950s, a lot of work was done
and certainly the differences were very obvious to the extent that fumigations carried out at a
particular dosage would certainly not control insects to the level required if those same dosage rates
were used on perhaps the next group of commodities where the level of sorption was considerably
higher. So, yes I think this has been well documented and, as I say, there's a lot of evidence in the
literature going back to the 1950s and '60s to substantiate this.
United States (Mr. Hirsh)
10.58 Thank you. The next question we'd like to direct initially at Dr. Heather. Because of the
presence of other uncontrollable sources of variation in small scale tests, we don't think that it's
possible to conclude that the differences in CxT values referred to by Japan are attributable or can be
attributed to varietal differences affecting efficacy of treatment. However, regardless of the source of
these variations, were the variations in CxT large enough to affect the efficacy of the fumigation
treatments for the commodities that have been raised in this proceeding?
Dr. Heather
10.59 I find it difficult to give a precise, clear answer on that. The problem, … I think I just better
leave it at that please.
United States (Mr. Hirsh)
10.60 The next question we note is similar to one that the Panel will shortly be asking but we would
like to come at the issue from a slightly different pe rspective. And that is with regard to the Panel's
additional Question 3, Japan refers to various sources of fruit variation including temperature,
moisture, daylight, rainfall, cultivation conditions and other natural conditions of the harvest year and
Japan states that these sources of variation, quote, are not widely known to result in significant

differences in efficacy of treatment, and this question is for Dr. Ducom initially. Are varietal
differences, quote, widely known to result in differences in efficacy of treatment?
Dr. Ducom
Could you repeat please?
United States (Mr. Hirsh)
10.61 We note that Japan has referred to a number of sources of fruit variation which include
temperature, moisture, daylight, rainfall, cultivation conditions and other natural conditions of the
harvest year, and Japan states that it has not considered these sources of variation because, quote, they
are not widely known to result in significant differences in efficacy of treatment. And my question is
are varietal differences widely known to result in significant differences in efficacy of treatment?
Dr. Ducom
10.62 It's the same. My opinion is that differences are of the same [nature], maybe, of the same
amount [importance]. I mean, I do not understand what Japan says. I mean why temperature,
moisture and so on? Since they are not known they are counted for nothing. That I cannot
understand. The same thing for variety. If we use the same argument varieties [aren't more
significant than other variables] are just nothing because [we have little data for varieties] we don't
know the answer for varieties. Or, if we take into account variety we should take into account
daylight, moisture, rainfall and so on.
United States (Mr. Hirsh)
10.63 Thank you. I would like to first ask whether any of the experts have had a chance to review
the study on apples which Japan recently submitted in Exhibit 36. This only came in last Friday so
I'm not sure whether you have had a chance, but before asking my question I want to find out whether
any of you have had an opportunity to review that study?
Dr. Ducom
10.64 Which one?
Chairman
10.65 Could you repeat the number of the exhibit?
United States (Mr. Hirsh)
10.66 Sure. It's Exhibit 36. It was submitted, I believe, last Friday together with Japan's comments
on Mr. Taylor's responses.
Chairman
10.67 So may I ask the experts, have you received the parties' comments to Mr. Taylor's responses?
Ok, they have them, yes.
United States (Mr. Hirsh)
10.68 In that study, with respect to apples, the author states on the final page of the study that the
factors affecting different CxT products were not specified in the test. For example, it appears that
there were no controls for length of time and storage, maturity of the fruit and fruit size. In addition,

we reviewed the CxT product data in Table 3 and in Table 5. In particular, the data for the Mutsu and
the Fuji in each table and that data appears to indicate that the two are not statistically different in
Table 5, but they are statistically different in Table 3. In light of the uncontrolled factors in this
experiment and the inconsistent data, is Japan's conclusion warranted that the differences in CxT
values noted in Table 5, quuote, were obviously attributed to varietal differences?
Chairman
10.69 Ok, I want to give some explanation now. The experts received that document when they
arrived in Geneva and they also had other documents which they received yesterday so I think they
have not been able to study these documents in detail. So could we agree that we give some time to
the experts so that they could answer your question later?
United States (Mr. Hirsh)
10.70 Certainly. Thank you very much.
Chairman
10.71 Ok, so we postpone answer to this question to a later stage, ok.
United States (Mr. Hirsh)
10.72 Those are the only questions which we have right now, Mr. Chairman. We do reserve the
right later following Japan's questions to follow up further.
Chairman
10.73 Ok, thank you. Does Japan have any follow-up questions to those questions United States
raised?
Japan (Mr. Yokota)
10.74 Mr. Chairman, may we confer within ourselves for a few minutes?
Chairman
10.75 Ok.
[break]
Japan
10.76 Mr. Chairman?
Chairman
10.77 Japan you have the floor.

Japan
10.78 Yes, we have one immediate follow-up question.
Chairman
10.79 Ok.
Japan (Mr. Saito)
10.80 I'd like to have one question but in Japanese so I ask to interpret my question.
Japan (Mr. Saito - interpreted)
10.81 I have a question to Mr. Taylor. Within the response to the US question … [can you hear, can
you hear? Can you hear Ok? Let me start again… ] I have a question to Mr. Taylor. In the first
question from the United States, Mr. Taylor responded saying that the sorption difference among the
cereals are commodity wise and varietal differences insignificant. But we would like to ask what is
Mr. Taylor's view with regard to the fruits which are the issue here in this Panel?
Mr. Taylor
10.82 Thank you for the question. I am not a specialist in the fumigation of perishables, I regret to
say. Therefore I find it very difficult to respond in any firm way to give you a definite reply to this.
All I could say is that the differences I would think would have to be very significant in order to make
it necessary to, for example, adjust dosage rates and/or time periods for the fumigation. If these
differences were so significant that the amount of methyl bromide available for the fumigation
process was significantly reduced by different varieties, then, in theory, this would be a significant
factor, but I think this has still to be demonstrated. Now you could say well why are there no
differences between different varieties of cereals? Again, the answer to that I cannot give you. In
fact, I think that in practicable fumigation the application rates always have such a margin [excess
over and above the minimum dosage] that any small differences would be accounted for by this
margin, or excess that is used. I would imagine that where the United States uses a 10-20% buffer, as
I think is the term used, this again would account for it [any small differences]. So in practical terms,
as I say, I think we would need to find that there is a significant difference between the varieties and
that this needs to be demonstrated. I feel that I cannot say any more on this subject from my own
personal point of view. Thank you.
Chairman
10.83 I'd like to ask do the other experts like to add something to this? I don't see. Ok. Then I give
the floor to Japan to present your, so to say, own questions.
Japan (Mr. Yokota)
10.84 Thank you Mr. Chairman. May I first of all, and on behalf of the Government of Japan,
specially thank Dr. Ducom, Dr. Heather and Mr. Taylor for agreeing to serve as experts on this Panel
and to give us their very valuable opinions on this matter. We have prepared a series of questions and
I would like to ask Dr. Kawakami to present them.
Japan (Mr. Kawakami - interpreted)
10.85 I would like to speak regarding those questions raised by the Panel and I consider there are
five points of importance so I would like to raise them one by one. First of all we should like to
express our heartfelt appreciation to the Panel for giving us the opportunity to present our views on

the pending issues of today. Also we should like to give our highest respect to the three respectable
experts, Dr. Heather, Dr. Ducom and Mr. Taylor for rendering valuable comments from the technical
point of view on the methyl bromide situation of perishable products which we think is a highly
complicated aspect of treatment technology and in which much more research and investigation are
needed for the situation of the issue in question. The Panel sought for expert comments from
technical point of view on as many as 18 questions. Of all these questions we consider that the
following five issues of argument are particularly important.
10.86 First issue: Whether or not to be the use of dose response … [ interruption]
Chairman
10.87 Excuse me, excuse me Japan's delegation that I interrupt. But I think that this submission is
better suited for tomorrow, because today we are expected to use the expertise of the experts that are
present. Your presentation is welcomed, most welcomed to the Panel but I think it is more
appropriate to present it tomorrow when we meet between the parties and the Panel, and today we
should devote our time and effort to use the expertise of the experts to the greatest extent. So if you
could agree with that, I would like to ask you to postpone this presentation for tomorrow. Thank you.
But if you have specific questions to the experts you are welcome of course.
Japan ( Mr. Sanatani)
10.88 Ok. Thank you Mr. Chairman. We have prepared five questions to put to the experts.
Maybe we can deliver the written questions to the members in this room? The first question is to Dr.
Heather and Mr. Taylor. I will read. Dr. Heather states in response to Question 12, quote: if only
one variety has been presented in the initial testing the possibility that other varieties which might be
proposed subsequently could have higher predicted minimum dose requirements would be greater.
Even so, the likelihood of this exceeding 10-20% buffer appears low, end of quote. Similarly, Mr.
Taylor states, quote: any varietal differences affecting the efficacy of MB treatment are unlikely to be
so great that the buffer of 10-20% fails to account for these differences. Effective quarantine
treatment is therefore to be expected, end of quote. Japan wishes to know the grounds for these
assumptions that possible varietal differences in most cases could be covered by the buffer 10-20%
surrounding the buffer. So, shall I stop here or continue to finish it?
Chairman
10.89 I think it's better to take the questions one by one. So, Mr. Taylor and other experts who..?
Dr. Heather
10.90 Perhaps if I could give the first response on this, please. The grounds for my conclusion were
that each of the varieties which had been tested in each of the commodities always met the large
confirmatory dose test. There was never any suggestion of failure. Therefore, had the dose been
pitched too low in the first place, this would have shown up as survivors from the large scale test.
The basis of this problem is partly that we are judging differences at points where they are quite
discrete but the effectiveness of the treatment becomes apparent at very, very high efficacies when
there are very, very few survivors and this has the effect of bringing together the differences so that
they are no longer apparent.
Chairman
10.91 Mr. Taylor, do you want to respond also? Ok. May I ask Japan to proceed to the next
question?

Japan (Mr. Sanatani)
10.92 Thank you Mr. Chairman. The second question is posed to all the experts. I read, Dr.
Heather states in response to Question 13: The broader applicability of a confirmatory test done on
samples of one variety over commodity depends on the extent of variation of mortality attributable to
varietal characteristics and a large scale test provides assurance for the extension of an existing
successful treatment to additional varieties of a commodity, provided that the initial varietal sample is
representative of the commodity. In response to Question 16, Dr. Ducom states: Extrapolation to all
available varieties is no more scientific than the Japanese's contrary assertion. They seem to concur
that there is no valid scientific ground to conclude that a treatment established for a particular variety
by confirmatory tests would be efficacious for any additional variety. Is this correct?
 Dr. Ducom
10.93 Yes that is correct. I mean I cannot see any more scientific basis on the Japanese side than on
the USA's side to say [that each] variety must be carefully treated … or for one we can have all
varieties. I hope you understand. In my opinion it is not scientific to say that one variety is equal to
all others, … but [choosing one variety as representative of all is the same sort of argument for me] to
say maybe one variety, it's the same for me. Ok.
Chairman
10.94 Thank you. Other experts, do you want to add?
Dr. Heather
10.95 Just responding to the first part of the question. The broader applicability of the context of
that statement was to start with the basic facts and say yes, technically, if you develop a treatment on
one and seek to apply to others. And then I went on to say that there were no real grounds to be
concerned, I think you'll find.
Chairman
10.96 Thank you. Could you now proceed to your third question Japan?
Japan (Mr. Sanatani)
10.97 Mr. Chairman. Before we proceed, can we take some time to reflect on the answers ...?
Chairman
10.98 Of course.
Japan (Mr. Sanatani)
10.99 Mr. Chairman, if you permit us to go back to the question number one, we have some
comments to put on our answers to number 1.
Chairman
10.100 I think the place of the comments are tomorrow, but if you have follow-up questions, if your
follow-up questions, if you want to seek further clarification from the experts, you are welcome.

Japan (Mr. Saito)
10.101 OK. Thank you Mr. Chairman. So let us go back to question number one and this time in
Japanese.
Japan
10.102 (Interpreted) Concerning the question one in the replies from experts Dr. Heather stated as
follows… we asked in our question whether this buffer of 10-20% could cover all these differences in
the varieties, among the varieties, are based on scientific grounds and if this buffer has the scientific
grounds and in response to our question we, as far as we can understand, after the various
confirmatory test, the efficacy did not show a significant difference and that this is the data of
empirical of nature. What we are questioning here is that in all cases whether the buffer 10-20%
could absorb all this varietal difference and if that buffer would have the scientific grounds in this
manner. And if possible I would like to invite the comments from, or replies from all the experts.
Thank you.
Chairman
10.103 OK. I give the floor to the experts.
Dr. Heather
10.104 I am a little anxious if I understood the question clearly enough, but as far as I understand,
Japan is questioning where the 10 per cent or 20 per cent buffer came from. It is difficult to project
with certainty, by regression analysis, the [dose required for] efficiency and effectiveness of a certain
fumigant. By analysing the data, examining a certain range of doses of the fumigant (if the fumigant
has 100 per cent effectiveness, or effectiveness of killing insects), by adding to the fumigant some
amount, which one actually does in practice, in the actual research, we have examined all varieties
under a series of trials. Then we obtain the data from there. A normal procedure then is to confirm the
data by a larger-scale confirmation test. However, one can attain this objective by somewhat different
means; one is by taking a "single replicate", which Japan is demanding currently. Another would be
by setting "confirmatory loss" to as low a level as possible, based on research among them. If there
are surviving insects, we conduct such trials repeatedly. We call this the "repeated iterative approach".
In other words, it is the idea to seek for, to the ex tent possible, the lowest value to attain confirmation
of effect on a certain target. I think, therefore, that this can be regarded as a somewhat different
approach. Both, I think, are means to meet the very difficult problems we have to solve. To be
practical does not mean it is unscientific.
Chairman
10.105 I would like to give the floor to Dr. Ducom.
Dr. Ducom
10.106 I would like to add a question: why is the buffer 10 or 20 per cent? This may be accidental
and so why not 5 per cent? It is difficult to say these are enough for the variety, because we cannot
recognize them as a fait accompli [what is needed]. It implies to hypothesize, to some extent, how
much the sorption level is for each variety.
Chairman
10.107 OK. Thank you. Japan.

Japan
10.108 [Microphone not on. Probably Japan asking Dr. Taylor to respond as well]
Mr. Taylor
10.109 I agree with the opinion of the two experts, in particular, with Dr. Ducom's. In other words,
we have no data on sorption. There are no data indicating the difference of sorption between
varieties. So, the 10 to 20 per cent buffer was set arbitrarily (at random); it was not based on scientific
examination. However, such numerical difference [is the one which could absorb the difference
enough]. A 20 per cent [buffer] would be a substa ntial increase in volume. I cannot add anything
more, but I agree with the opinions so far expresse d by my colleagues, the two specialists. We have
no data as to what constitutes the rate of sorption of each variety. If we do, we could possibly decide
whether this 10 or 20 per cent is too high or too low, and a 5 per cent buffer may well be enough. But
we can present no scientific evidence other than that.
Chairman
10.110 Thank you Mr. Taylor. Japan?
Japan
10.111 Thank you, Mr. Chairman. Since we have finished questions number one and two, we would
like to move on to question number three, which is a question for Dr. Heather and Mr. Taylor.
Japan (Mr. Sanatani)
10.112 ….. Dose-response testing is a tool commonly used for the purpose of comparing reactive
resistance to a treatment such as between development stages of insects. Results of the tests are
statistically analyzed using probit analysis, normally by way of comparison of LD50 values. This is
supported by Exhibits 19 and 20 of the Japanese submission. There is no disagreement among on this
point; in particular, Dr. Heather and Mr. Taylor explicitly acknowledges the effectiveness of dose-
response testing and probit analysis. Japan solicits the experts' opinion as to possible application of
dose-response data and probit analysis to a comparative inquiry into differential effects of fruit on
mortality. Thank you.
Dr. Heather
10.113 It would be a very interesting study, but in such study, from my experience, variation will
[originate from both the] fruits and their harmful insects, and it will depend, I think, on how such a
treatment is indirectly given. Therefore, it would be difficult to obtain practically useful data from
such a study.
Chairman
10.114 Mr. Taylor.

Mr. Taylor
10.115 I agree with the opinion of Dr. Heather. It woul d be very interesting to know how useful the
data will be that comes out as a result. Of course, if Japan is really thinking of doing this, it would be
useful. If Japan could make public the result, it will shed light on the issues for which the answer is
unknown, or there is no data. Thank you.
Chairman
10.116 Japan.
Japan (Dr. Nakakita)
10.117 I am not good at English and would like to intervene in Japanese. Dr. Ducom, I believe you
mentioned that LD50 cannot be used for these kind of purposes and as a basis of your saying that, the
Journal of Economic Entomology submitted by the United States, the 1987, and which refers to six
varieties of nectarines, they are indicating the comparative tests and ... codling moth eggs ... 6.3
grammes per cubic metres. This is the LD 50 and this was the lowest value obtained among those six
varieties. However, with regard to the efficacy at the higher concentration level Summer Grand, is the
variety that indicated the highest resistance. So Dr. Ducom seems to be saying that the LD
50 does not
really have the validity, I believe that's what you said. But looking at this report this does indicate the
difference between the varieties. And I believe that in this regard this is a report that should command
lots of attention. So I believe that this report should attract attention in that regard. But in 1997, in
the United States, another report published in the United States which refers to the Summer Grand's
test results of 1987 and it came up with a newer data that replaces the old data of '87 and in this new
report the value of LD
50 was not that small. And LD 95 also indicated the value that is not that much
different from the LD95 of other varieties. So, the data obtained in the testing done in '87 with regards
to the Summer Grand's resistance was in a way negated. And also, May Grand, the variety called the
May Grand, the LD 50 and the LD 95 are listed next to each other and when you look at those in May
Grand LD50 and also LD95 both indicate a higher resistance than that of Summer Grand but the 100%
mortality values is lower by 25% than that of the Summer Grand, so I am somewhat dubious with
regards to the reliability of this report. What is your observation on this report Dr. Ducom?
Dr. Ducom
10.118 It is very difficult to answer, to know what happened. For myself we have carried out a lot of
trials like that and sometimes we have found black and sometimes white. I don't know why, although
I should. I would appreciate it if I could know wh at happened. But, no, I have no answer. I don't
know why. That's the only thing. It's when you do trials like this one with LD 50 or Probit 9 analysis.
Like Dr. Ito says, it depends, sometimes it works. When we say it works, it is logical with what we
want to get, but if the results are not what we want, then we say it doesn't work. I don't know what the
truth is. I have no more comment about that. I am sorry Kawakami-san.
Chairman
10.119 OK. Thank you.
Japan (Dr. Nakakita)
10.120 Thank you. I would like to ask Mr. Taylor, do you regard this as a scientifically reliable data?

Mr. Taylor
10.121 Could you just refresh my memory as to which, are we comparing the 1987 report with the
more recent one? Is this what you are asking me to report on, or to give my opinion on? Please could
you just, when you say you would like me to give opinion on to...
Mr. Nakakita
10.122 The report. 1997, sorry. That's the year the Americans submitted report. And '87 which was
on general insect product research.
Mr. Taylor
10.123 Thank you Dr. Nakakita. I find it difficult to make any firm statement. I mean I have read
these two papers but it's very difficult to know why there is this difference and to actually give with
any affirmity which of the two is correct and why there is a difference. I mean Dr. Ducom has
already stated that sometimes you get one set of results and sometimes you get another set of results
when you may be expecting similar results. I'm sorry, I cannot with any confidence give you any
other answer than to say that unless there are any differences that have not been accounted for in these
two experimental programmes which we might have to re-examine to see whether there was anything
about the two experiments which leads to that conclusion. I don't know whether Dr. Ducom would
like to make any comment as whether he thinks there might have been some possible experimental
difference which has not been taken into account?
Chairman
10.124 OK. I think you cannot extract more from our experts.
Japan (Mr. Nakakita)
10.125 Thank you very much Mr. Taylor and Dr. Ducom.
Chairman
10.126 OK. Can we move now to your fourth question?
Japan (Mr. Sanatani)
10.127 Thank you Mr. Chairman. I read: In the course of dose-response testing and tests on CxT
values, fruit and insects are inserted into a small and highly airtight fumigation chamber. The
material of this chamber shows a low level of sorption. Moreover, packages and other factors which
might affect the result are consciously eliminated. Japan considers, in light of these experimental
conditions, that, should there be any significant differences between test subjects, it is reasonably to
estimate a link between fruit and the results. Japan wishes to ask experts about their thinking on this
issue. And if it's possible we like to deliver pictures of the dose mortality tests and with your
permission I would like to invite my colleagues to put some explanation on it.
Japan cont'd (Dr. Kawakami)
10.128 In these photographs these are the pictures of the dose-response tests. This is testing of the
sorption. This is a very small scale gas tight chamber. The chamber itself doesn't really have any gas
sorption and we place two different varieties and we examine the rate of sorption for those responses.
And of course we have to look at the factors such as the packing materials' existence or chamber's air
tightness but those factors are eliminated. Within this chamber only the fumigants and fruits and
possibly the pests that are staying when the fruits are inside of the chamber. The Panel seems to share

a view that the data is somewhat varied but we feel that the data obtained from this kind of an
experiment is highly reliable so I believe this kind of a test does indicate the different responses or
susceptibility of different varieties of fruits to a given measures. So if we could have your comments
on this we would appreciate it.
Mr. Taylor
10.129 Could I please ask [the Japanese side if] this chamber is dosed with fumigant when it is
completely empty. If this is repeated what level of variation would there be doing a test on the
chamber before any fruit is put into it? In other words, what variation would they expect between
tests prior to using the chamber actually for ex perimental work? So an empty chamber of this
particular type, would they have any indication of what is a variation if, say, four or five tests were
carried out on an empty chamber? What might be the variation it might expect using obviously
exactly the same dosage technique and measuring technique?
Japan (Dr. Kawakami)
10.130 Of course before we carry out our test the emptiness and absorption characteristics of gas are
studied, but in this regard there is no variation. As for in terms of percentage it would be in the
magnitude of under one percent of variation and of course that is based on the empty chamber.
Chairman
10.131 Dr. Ducom?
Japan (Dr. Kawakami)
10.132 In addition these tests using these kind of facilities, are quite generally conducted worldwide.
In the United States probably Dr. Ducom would use the same technique and in the United States and
New Zealand I note instances where these facilities are used and these kind of tests are conducted and
they are all of quite a similar nature.
Chairman
10.133 OK. Who wants to take the floor, Dr. Ducom or Mr. Taylor? Dr. Ducom.
Dr. Ducom
10.134 Yes, we do use something like that but my problem, my concern is the number of fruits used.
For example, for stored product sorption trials we use, for example, 200 millilitre glass jars [tape
change] ... that means about 100 grammes of wheat, which means 2,000 [cereal grain] kernels. If you
take six apples, or something like that, variation must be very high. I mean, if we could use
something like 1,000 or 2,000 apples each time it could be very more much precise and confidence
limits could be very good. We do [it using the same small amount of apples as you because that is
what you ask of us] like you because you ask just th at, but I would prefer to know that each variety is
tested using a lot of fruits to be able to smooth the differences.
Chairman
10.135 Mr. Taylor, do you want to add?
Dr. Heather
10.136 Perhaps I could just have a word. I would compliment the Japanese researchers on the quality
of their laboratory equipment. Speaking from my own view point I had no doubt whatever about the

results coming from such an experimental set up. Where I have reserved my judgment is on the
application of those findings or to attribute those findings entirely to varietal differences. It has been
my experience with a number of fruits that they vary greatly from year to year, from the locality
where they are grown even though they are the same variety, and even in a batch of fruit there will be
fruit to fruit variation. Now, I am not certain, I am not convinced that sufficient of the variation is
unique to the variety to justify the conclusion that the data, the differences in the data, prove that the
cause of this difference is varietal, predominantly varietal, it could never be totally. And this is the
reservation I have.
Chairman
10.137 Ok, thank you. Can we now proceed to your next question Japan?
Japan (Mr. Sanatani)
10.138 Thank you Mr. Chairman. Now I move on to question number five. Dr. Heather clearly
acknowledges that differential sorption levels due to varieties and other causes could affect efficacy of
fumigation. While he refers the question of causes of sorption levels to other experts in fumigation
chemistry, Dr. Ducom and Mr. Taylor acknowledge that sorption of methyl bromide takes place in oil
contents, surface or protein and variation of these factors result in different sorption levels.
Differences in variety often mean differential cont ent levels, such as the oil content in in-shell
walnuts. Japan believes from these statements of experts that they recognize possible varietal
differences which affect sorption levels and hence efficacy of a treatment, and wishes to ask the
experts to confirm this. Thank you Mr. Chairman.
Chairman
10.139 Mr. Taylor?
Mr. Taylor
10.140 Thank you Mr. Chairman. I don't think any of us would fail to agree that sorption and, as I
mentioned earlier, temperature are the most important factors affecting the efficacy of fumigation
assuming that we're not losing gas due to leakage. And certainly the mention of in-shell walnuts is
very applicable. Differences in variety of course, where there is sufficient difference of sorption
could well, therefore, affect the efficacy of the treatment. Surface area is again a particular property
which, if it was sufficiently great, would affect the treatment. But the oil content, and of course
anything else such as the protein which would remove a certain quantity of the gas from the free
space, are all important factors that we agree on, and have been researched over many years. So I
don't think any of us are in dispute that sorption would be a major factor affecting the efficacy of
treatment, and if it can be demonstrated that sorption is of sufficient magnitude between different
varieties, this would affect the efficacy of treatment, but I think that this has still to be shown and to
be demonstrated. We go back to the obvious difference between durable commodities where some
commodities virtually absorb no methyl bromide, rice , for example, compared to in-shell walnuts. I
mean the dosage rates would be dramatically different and if we use the dosage rates that we
recommend for rice, for high oil content commodity such as walnuts or any of these similar
commodities, such as peanuts, then the efficacy of the treatment would not be in doubt, it would not
be effective. So I just have to summarise what is your question and what it is that we confirm. I
certainly would confirm that if the difference in sorption between varieties was of a sufficient
magnitude, then there would be need to consider whether or not the treatment would be efficacious
using rates which had been recommended for a variety where there was little or no sorption. Thank
you.

Chairman
10.141 Dr. Ducom?
Dr. Ducom
10.142 Just a comment. Yes, I agree totally with Bob's statement. I just advise something about
sorption. Levels are important for varieties but that means no insects, no LD 50 trials to show that
sorption is different. I mean we don't need any insects and any dose mortality tests to show that
sorption is different and it makes very different, it's very easy, it's easier to run a sorption test than the
dose mortality test. That's an important point in practice.
Chairman
10.143 OK, thank you. Have you now concluded your questions Japan?
Japan (Mr. Sanatani)
10.144 Yes, Mr. Chairman.
Chairman
10.145 Thank you. I now turn to the United States. If you have any follow-up questions to the
experts on the basis of the questions presented by Japan.
United States (Mr. Hirsh)
10.146 Thank you Mr. Chairman. May we have a few minutes to consult?
Chairman
10.147 Of course.
[break]
Chairman
10.148 Ok. United States, are you ready to proceed?
The United States (Mr. Hirsh)
10.149 We are Mr. Chairman. Just one follow-up question for Dr. Ducom. In connection with the
question regarding whether it is possible for the United States to prove the negative, that is to say that
United States understands that it is not possible to prove a negative and that it's not possible to state
with scientific certainty that at no time in the fu ture will there possibly be a varietal difference that
might, as a hypothetical matter, affect treatment of efficacy. But, Dr. Ducom, are you aware of any
circumstances in which a difference in variety has in practice required a difference in a treatment level
among the products at issue?

Dr. Ducom
10.150 I am not a [fortune teller] definition man, or something like that. I cannot answer that. That's
why there is a variety problem. We don't know, you don't know. Intuitively I can imagine that there
is no difference between varieties. When you see one nectarine next to another it seems the same. It
seems to be obvious that they are the same, but sometimes, we cannot [prove it], it's not a proof and to
be able to have proof we need some tools.
United States (Mr. Hirsh)
10.151 I understand, but let me rephrase the question. Are you aware of any circumstances in which
variety has made a different, not for the purposes of establishing with scientific certainty that there
will never be a difference but just simply are you aware of any situation which variety has made a
difference in a treatment level and we'll take an answer from any of the experts on this.
Dr. Ducom
10.152 Not as far as I am used to study anything like that. Not in perishables. Yes for stored
products like nuts, which are in fact stored products.... There are differences in varieties in walnuts
because of oil contents. Maybe we can have the same for raisins, but maybe you do not agree with
that, but for perishables, no. I can imagine it like Japan says, but have never seen something like that.
United States (Mr. Hirsh)
10.153 If I might ask one more follow-up question? With regard to walnuts, if in fact the oil content
among varieties did not differ, would you then state that there would not be a difference among the
varieties?
Dr. Ducom
10.154 Probably yes [not], but I have never done any trials on that. But I can imagine that there is no
difference in the [varieties as far as methyl bromide is concerned] because the oil content is the main
factor of sorption for walnuts.
United States (Mr. Hirsh)
10.155 Thank you, and if any of the, if either Mr. Ta ylor or Dr. Heather would like to answer the
question regarding whether they're aware of any situations where differences in variety have resulted
in a different treatment level for the products at issue in this case.
Mr. Taylor
10.156 No, I have no information or have seen any published data so the answer I have to give is no.
Chairman
10.157 I think that, Ok Dr. Heather?
Dr. Heather
10.158 In my experience there have been no differences of this kind. In fact it's been to the contrary.
Most of my experience has been with insecticide dips with the material dimethoate and here we find
that the same treatment not only goes across varieties but across commodities but I can see that this
sorption problem with methyl bromide is something ve ry special and that's why I wish to defer to my
colleagues with experience as fumigation experts.

United States (Mr. Hirsh)
10.159 Thank you very much. That's our only follow-up question.
Chairman
10.160 Ok, thank you. Now I ask your patience for the Panel to have an internal consultation. So
this is the same privilege as we have given to the parties.
[break]
Chairman
10.161 And thank you for your patience for waiting us.
United States (Mr. Hirsh)
10.162 Mr. Chairman, if I may be recognized? Before proceeding to the Panel's questions would it
be possible to ask the experts whether they've had a chance to consider our final question?
Chairman
10.163 I forgot that. Any volunteers? Ok, perhaps we could have a coffee break or a lunch break
and we go to that question after that but we will see because now we can anyway proceed with the
questions by the Panel. During our recent break we considered whether we could delete some of our
questions because they have already been covered and yes indeed that is the case but we have tried to
compensate that by elaborating some new questions in addition.
10.164 So, I first note that we will not present the questions one, two and three because we consider
that we have already received adequate answers to the questions which are there. So I will
straightaway proceed with our question number four and I will read it: In its answer to US question
eight Japan states there is a precedent in which Japan has approved importation of all varieties in a
commodity, namely lemons, grapefruits and ponkan oranges are approved subject to a cold treatment
against fruit flies. This is because varietal differences of these commodities are minor for reasons of
their history of development by somatic mutation such as bud mutation, and they are not known to
lead to a significant difference in the efficacy of a treatment. Are apples, nectarines, walnuts and
cherries different in this respect? Is the Japanese position quoted above scientifically reconcilable
with its position on MB treatment for apples, nectarines, walnuts and cherries? Dr. Ducom.
Dr. Ducom
10.165 Thank you. The question is difficult. There is an affirmation. I mean genetically speaking
what is the difference between a mutation and crossing to get a new variety? I mean, for example,
you can have small differences or big differences. The difference between peach and nectarine is a
mutation. We have a big difference and though somatic mutation must lead to big differences, I
cannot agree with that argument. But not scientifically speaking.

Dr. Heather
10.166 I would find it difficult to answ er directly without seeing the genetic origins of each of the
varieties involved but I would have thought that lemons would not have fitted the bud mutant
definition but I would like to reserve that decision. It's something that I would have to research.
Chairman
10.167 OK, thank you. I now move to our question number five. In your expert opinion is there an
objective or rational relationship between the varietal testing requirement imposed by Japan for MB
treatment and any of the evidence submitted by the parties?
Dr. Ducom
10.168 I've a quick answer. In the absolute yes, in practice no.
Chairman
10.169 Could you repeat that?
Dr. Ducom
10.170 In absolute, maybe yes, but in practice no. I mean the arguments are not statistically good.
Scientifically, they may be good, but in practice th ey may be too narrow. But the answer is really
difficult.
Chairman
10.171 Ok, Mr. Taylor?
Mr. Taylor
10.172 I have to agree with Dr. Ducom. The answer is very difficult otherwise perhaps we would not
be here. Again I think in theory there may be some differences which perhaps exist, but in practice it
is difficult to show these and it seems very difficult in fact to say that at this time the differences that
might make the difference between treatments efficacious and non-efficacious have not yet been
reached and therefore I think at this moment in time that the evidence is not sufficiently strong
although in theory it does have some possible validity. But at this stage, as Dr. Ducom has said, and
in practical terms, it's very difficult to say yes there is something which is sufficiently demonstrated to
show that there is a real problem which has to be addressed in terms of maybe variety-by-variety
testing, and which could lead to differences in the treatment techniques that are used.
Chairman
10.173 Thank you. Do you want to add something?
Dr. Heather
10.174 More to agree with both of my colleagues. I'd say yes there is a relationship but it is an
incomplete one but this is a real world and to totally complete the relationship of these and decide on
how important it is, I think would probably be bey ond the resources even of the United States and
Japan in the time available, and I'm not sure that it would really add anything of great value to the
argument.

Chairman
10.175 OK, thank you. I only want to state already now that we in the Panel also appreciate when
you answer that you don't know. Then we move to our question number six. Here perhaps some
words of explanation why we are asking this question. It is because the SPS agreement uses these
expressions like "specifications of a product" and "modified product". Those are quotations from the
SPS Agreement and now that's why we are presenting this question. The question is: From a
technical or scientific point of view, first, can the development of new varieties of a product be
considered as changes in the specifications of the product, and secondly, can a new variety of a
product be regarded as a modified product?
Dr. Ducom
10.176 It is always difficult to answer your questions. It's about the relationship between the product
and methyl bromide, you are talking about. I mean that a specification of a product means sorption
model with methyl bromide. We are not talking about generally speaking, the colour we don't care
about. We just want to know if the change in the new varieties has a different [reaction to] version
against methyl bromide. I mean we should have to ols to know that. You know, a fruit can be the
same, appear in the same shape, the same as a colour and so on and may have another reaction to
methyl bromide. Why not? We don't know. If we have no tools we cannot say if a new variety is a
new variety of it or .... [interrupted]
Chairman
10.177 Excuse me. Now I think I should have explained more in detail what we are asking. Here we
are not asking of methyl bromide or the efficacy, anyt hing. This is just a biological question I would
say. Whether new varieties can be regarded as that. You see, in our [SPS] agreement we have
provisions that if a product for instance has already been approved then if the specification has been
changed or the product has been modified then a new approval should concentrate only on those
changes which have happened. So that is why we are asking this question. It is not related directly to
methyl bromide or any efficacy questions but just how you could, would interpret this or could you
interpret these words in our Agreement?
Dr. Ducom
10.178 That's the kind of question we are not experts to answer but I should say, yes, there are some
changes in specifications, but it's just in my own opinion.
Chairman
10.179 Do you want to ask something?
Dr. Heather
10.180 Only to say that the judgment becomes a subjective one and it really depends on the breadth
of the definition of the product in the first place and the size of the changes in relation to that.
Chairman
10.181 Ok, thank you. We now move to our question number seven. In Dr. Ducom's answer to
Panel question three it is stated that the dose mortality tests presented by the parties are designed to
give information on insect sensitivity. The search for possible causes of varietal variations cannot be
determined with precision by them but only with a specific research program. Is it technically
possible by such a research program to determine the degree to which variety matters for quarantine
efficacy of MB treatment?

Dr. Ducom
10.182 I am sure that either the US or Japan can imagine the design for a research program on that. I
mean as far as I know, never, there has never been a study on that because may be no need had
appeared before. Now we are at the point where perhaps that kind of research could be carried out.
I'm sure we can find something to approach [evaluate] the varietal differences.
Chairman
10.183 So your answer is yes?
Dr. Ducom
10.184 Yes.
Chairman
10.185 OK, thank you. I then move to question number eight but here we have added something, for
Dr. Ducom's delight! Namely we would like Dr. Ducom to elaborate not only on the amelioration of
statistical methods which invalidated the hypotheses of a statistical difference mentioned in his
answer to Panel question eight, and also if you could elaborate on what you said today on the
difference between biologically relevant difference and a statistically relevant difference between
varieties of a product, as it relates to the studie s before the Panel, because we must admit that we
didn't fully understand these two notes of you.
Dr. Ducom
10.186 First of all about amelioration of statistical method, it appears with Yokoyama and Robertson
presented in US Exhibit 15. It's about the re-analysis of data from the experiment on nectarines from
1987 and with probit analysis … [found that] there are very big differences between Summer Grand
and other varieties of nectarine. And with the new software like Polo and new methods created by
Jacqueline Robertson, they found that the difference is not significant, even if the probit lines of the
LD50 or 95, are very, very different. With a new statistical approach we [suddenly no longer have] can
have no more differences. For people who don't know statistical, it means like poor arrangements but
in fact in statistics you can choose the best tool because all are relevant. … For the same experiment
you have bad tools and good tools, statistical good tools, statistical bad tools, and times also helps - I
mean now we have better tools than before. That's for the first point [change of tape] biological and
statistical answer and significance. I mean when you have two differences between, for example,
LD
50 for Fantasia and, or, OK, two varieties of nectarine which is 10 milligram by cubic metres and
the overlap, the confidence limits, is maybe 11.36 and the other one is 11.45, you say statistically it's
different, but biologically speaking it's not different. But the problem is that statistically we can make
the difference biologically we cannot make the difference. We can imagine that there is no
difference, but we cannot prove without any further trials. That's the problem.
Chairman
10.187 We now have an additional question to whomever wants to answer it. We have discussed
quite with some length already the impact of sorp tion. Now the Panel would like to know a little bit
more about this. First, how is the sorption test conducted and how feasible would it be to test sorption
values for each variety? And has this been done in any of the studies before the Panel? Dr. Ducom?
Dr. Ducom
10.188 Sorption tests may be carried out very easily, I guess, for the people who are used to make
trials on perishables or stored products. I mean, the interest is that it could be made without insects

and just after the crop, the time exactly when fumigation has to take place. That means, for example,
for the apples – the paper we have not time to read exactly from Kawakami-san – when you carry out
experiments on apples some are cropped maybe in August or September, others in October. We put
all them in the [cold chamber] fridge, in the, ok in the fridge, and the reaction may be different. If you
do trials at the August for the August harvest, [or wait until] October and November, each one in his
ripeness time or in the time where fumigation has to take place, maybe two months later, for each one,
but not three months for one [may lead to different results]. And with enough fruit I guess we could
have some good answers on sorption and maybe also try to know what the factors which make a high
sorption are; maybe it's due to proteins, I don't know, of the nature of the skin, I don't know. That's
the research program could that could be allowed to find the factors which can influence the sorption.
Chairman
10.189 Ok, and the last part of our question was has this been done in any of studies before the
Panel?
Dr. Ducom
10.190 No I don't think so, not by itself. But maybe in Kawakami-san ['s paper] I don't know.
Chairman
10.191 Ok, Mr. Taylor?
Mr. Taylor
10.192 Thank you Mr. Chairman. One or two comments. You mention how a sorption test was
carried out. Well by exposing the commodity in question to a known concentration and the
concentration of the methyl bromide is measured very accurately over a period of time to see to what
extent the gas concentration falls. Another way of course, an additional way, is to measure to see if
there are reaction products and to see whether there are bromide residues within a commodity treated.
So there are several ways to actually test to what degree a particular commodity will absorb the gas.
There are quite well known methods by which accurate levels of sorption can be tested. I mean, we
have to appreciate that some of the sorption is permanent where the actual gas reacts with a
commodity, a sort of chemical reaction which leads to the bromide residues. On the other hand, some
of the sorption is reversible and the gas will be eventually released again from the product. But
certainly techniques such as these have been conducted over many years so there should be no
problem in actually conducting these trials. As Dr. Ducom said, to determine the sorption of fumigant
would not involve insects in these test, just the gas and the commodity, and from these tests to see to
what extent there is a difference between varietie s as between commodities, and to determine just to
what extent this is an important factor and whether the level of sorption is very high or very little
difference exists between the two. Thank you.
Chairman
10.193 Thank you very much so, and also, to Mr. Taylor the last part of our question, has this been
done in any of the studies before the Panel?
Mr. Taylor
10.194 I don't recall having seen this having been done, just on a variety by variety basis in which we
could actually say this variety absorbs this much and another variety absorbs a different value or the
same value. I don't recall having seen this being done specifically on a sorption test basis for different
varieties.

Chairman
10.195 Ok, but do I understand correctly then your answer is that there exist methods, established
methods to do such tests and that the results are rather reliable?
Mr. Taylor
10.196 Yes, I think that's correct, yes. This work could certainly be conducted I'm sure either in
Japan or the US and their research programs could conduct this technique if they were minded to do
so.
Chairman
10.197 OK. Thank you very much. Now I turn to our question number nine which is rather lengthy.
We have been made aware of a so-called CxT value and now we try to test whether we have
understood anything. And so the question reads as follows: It is the Panel's understanding that
quarantine efficacy for a certain pest at a certain stage can be obtained by determining the
concentration of the fumigation in the chamber and the time the pest is exposed to it by determining a
fixed CxT value, that is to say that if a codling moth is fumigated for a certain amount of time at a
certain concentration the test will die. If the fumigation process can be monitored so that the
concentration of the gas is maintained at the required level during the required period time varietal
differences, such as sorption, as well as any other factors would not affect quarantine efficacy and
probit 9 mortality would be ensured. Is this understanding correct? Would such process be
technically and economically feasible?
Dr. Ducom
10.198 Yes and yes. Ok.
Chairman
10.199 Yes, I would also ask the other experts. Mr. Taylor?
Mr. Taylor
10.200 Thank you, Chairman. Yes I have to agree with Dr. Ducom. In many cases of course of
fumigation of other situations, such as the treatment of flour mills, there is regular monitoring, as we
call it, of the fumigant level. It may be necessary to increase the fumigant concentration by adding
more fumigant for example, because of some factor, maybe leakage, etc., so I mean this is certainly
something that can be done, and is done, and if this type of technology was employed whereby the
concentration is monitored regularly and it is found to reach the required level, in other words, you
will end up with the CxT product value that you have said is necessary, then this will be an effective
treatment and I mean so this is technically feasible. I will reserve judgment on the economic
feasibility to those that know more about the topic than myself. But probably it is. I would think it to
be probably technically and economically feasible.
Chairman
10.201 Thank you. Dr. Heather?
Dr. Heather
10.202 To the first part of the question, yes, I believe so. To the second part, I'd have to defer to my
colleagues who know more, who have more practi cal experience of fumigation, but I am aware that
grain in my home State is controlled by the use of a CxT approach rather than an outright dose.

Chairman
10.203 Ok, thank you. That was most helpful so I conclude that more or less the Panel has
understood what you have said. Ok, then I have one last question at this stage and this is of another
character and it reads as follows: Does the risk assessment conducted by Japan for preventing the
introduction of codling moth provide scientific basis to ban the import of the products in dispute? I
repeat, does the risk assessment conducted by Japan for preventing the introduction of codling moth
provide scientific basis to ban the import of the products in dispute?
Dr. Heather
10.204 I would agree that codling moth is of sufficient importance as a pest and the risk to Japan,
which does not have this insect, is major and, yes, on that basis they are entirely [justified]. Their
conclusion that it's a pest which requires an initial ban on importations [I would agree] to be quite
appropriate.
Chairman
10.205 Ok, Dr. Ducom and Mr. Taylor, do you want to add?
Dr. Ducom
10.206 I am not an expert on pest risk analysis and therefore I cannot answer.
Chairman
10.207 Ok. Mr. Taylor?
Mr. Taylor
10.208 I would agree with Dr. Heather that certainly it does seem as if there is sufficient risk from the
pest to ensure that measures are taken to keep it out but I would not like to go so far as to say that it's a
ban on the import of the commodities. I wouldn't like it to be recorded that I would say that. I would
certainly say that the risk analysis seems to be sufficient to make sure that the pest is kept out but I
would repeat that I would not like it to be taken dow n in perpetuity that I had said that the products
therefore ought not to be allowed in. But I would say that obviously the Japanese government
obviously wants to make sure that the measures that they take to keep the pest out are as good as can
be possibly effected.
Chairman
10.209 Ok. Dr. Heather?
Dr. Heather
10.210 If I could add to my comment. The initial reaction is prohibition. This is a normal quarantine
regulatory approach and then there is conditional admission which usually depends on a treatment. I
think conditional was the word Japan uses, it's quite appropriate. So this was my intent to say that
initially prohibition and then some measures are required.
Chairman
10.211 Ok. Thank you very much. That was most helpful.

10.212 Now I want to inform you that it is the intention of the Panel to still ask some, I would say,
short, and I hope, simple questions which are of a confirmatory nature. That means that we have tried
to understand the scientific and technical background for this dispute and now we want to get
confirmation or not confirmation by the experts, but before I present those, I would say, confirmatory
questions, we need some time. So I announce a coffee break of, say, 15 minutes and I hope that the
experts could use those 15 minutes in preparing their answer to the question by United States which is
still outstanding. Ok, could we agree so? So, 15 minutes.
[break]
Chairman
10.213 ... for the delegations, United States and Japan, whether you still have some additional
questions you want to present to the experts? This is the last, ok, last opportunity for that. And after
that I will give the floor to the experts one by one for any concluding remarks they want to make.
After that I will announce lunch break. After the luncheon we will reconvene again and then, as I
announced at the beginning of the meeting, the Pane l has the intention to present some, I would say,
confirmatory questions to the experts, whether we have understood some of the scientific and
technical facts in a correct way. Can we follow this procedure? Ok.
10.214 Ok, so first we take the United States' question. Perhaps you could repeat the question
because at least I have not, I cannot quite recollect what it was!
United States (Mr. Hirsh)
10.215 Give me one more chance at it. We refer you to the recent study by Japan included in Japan's
Exhibit 36. With respect to apples the author stat es on the final page of the study, quote, the factors
affecting the different CxT products were not specified in the test. For example, it appears that there
were no controls for length of time in storage maturety of fruit and fruit size. In addition, we
reviewed the CxT product data in Table 3 and Table 5, in particular the data for the Mutsu and Fuji in
each table which indicates that the two are not statistically different in Table 5 but they are
statistically different in Table 3. In light of the uncontrolled factors in this study and the inconsistent
data, is Japan's conclusion warranted that the differences in CxT values noted in Table 5 were, quote,
obviously attributed to varietal differences?
Chairman
10.216 Ok, now I give the floor to the experts. Dr. Heather?
Dr. Heather
10.217 It was a little difficult to decide who should answer this. Taking the statistical differences
first we've noted that the method used is a Tukey's multiple range test which is a statistical test I
believe appropriate to comparing results of trials rather than treatments within trials and statistics are
better explained by a biometrician but I would not be surprised to see a difference proven or shown,
not proven, shown, in one case and absent in another. This is just one of those aberrations that is
possible when you analyze data so that's part of it.
10.218 The second part, if I'm right, was where the author obviously attributed the differences to
varietal characteristics. We are of the opinion that it is not possible to attribute them solely to varietal
characteristics on the evidence that's present in this paper. It may well be true but it requires, it would

require… to reach that firm conclusion would require more information. The age of the fruit which
was involved, it would be normal to treat fruit which was freshly harvested but then again it would
also be possible to have involved fruit which had been harvested for some time and which was
subsequently determined to export it so that it is not an unreasonable, it's not unreasonable to store
fruit for a while before fumigating it but it would have been nice to have a small scale test to show the
difference between freshly harvested and stored frui t so it's more the scope of the experiment. Do I
have one more other question to answer?
United States (Mr. Hirsh)
10.219 I think that was it.
Dr. Heather
10.220 Thank you very much. I would like to congratulate the authors of this paper. Really, it's a
very comprehensive piece of work and our only, the only exception we take to it is that some of the
conclusions have gone perhaps a little further than we believe the data supported.
United States (Mr. Hirsh)
10.221 Thank you very much.
Chairman
10.222 Thank you. Taking into account the time I had to change the procedure I proposed. So
before the lunch-break I will present one additional question by the Panel to the experts. And after
that we will break and that will give the partie s also the opportunity to consider any additional
questions you wanted to present and also gives opportunity to the experts to consider what kind of
concluding remarks you want to present.
10.223 Ok. So I will now present one question by the Panel and after that we have heard the reply
we will break for lunch. This question here again I think I need some, I need to give some
explanation to the experts. You know that the sc ope of this dispute does not cover only the four
products, apples, cherries, nectarines and walnuts, but also apricots, plums, pears and quince, even if
we have not received any material from either party concerning those four other products. So now the
Panel wants to ask you the following question: To the best of your knowledge is what you have stated
about varietal differences concerning apples, cherries, nectarines and walnuts, would that also be valid
for apricots, plums, pears and quince?
Dr. Heather
10.224 Yes.
Chairman
10.225 All? All answered yes. Ok, that was clear and short. And now we can break for lunch and
we will continue at three o'clock, thank you.
[lunch break]

Chairman
10.226 .... outlined before the lunch-break the procedures would now be that I first give the floor to
the United States if they have any additional questions still to the experts, then to Japan for the same
purpose, then the Panel still has one small question to present to the experts. After that I will give the
floor to the experts in alphabetical order for any concluding remarks, and after as a grand finale I will
present some so-called confirmatory questions to the experts from the Panel. Ok. So, I now give the
floor to the United States.
United States (Mr. Hirsh)
10.227 Thank you Mr. Chairman. We have no additional questions.
Chairman
10.228 Thank you. Japan?
Japan (Mr. Yokota)
10.229 Thank you Mr. Chairman. We have three additional questions related, all of them related to
questions from Panel number nine, so I'll pass the floor to Mr. Sanatani to ...
Chairman
10.230 Ok. You're welcome. Could you take them one by one?
Japan (Mr. Sanatani)
10.231 Allow me to speak in Japanese. This is our follow-up questions, or rather confirmation to the
additional question number nine from the Panel. There are three points.
10.232 The first point: Regarding the method described in the point nine, or question nine, when the
pest is directly exposed to the fumigant, we understand that model dosage may be constant.
Assuming there is a difference of sorption amongst the varieties in order to maintain a certain CxT
value and therefore to kill the codling moth we would probably need to change the dosage or the
duration of the time of the exposure depending on the varieties. And this is our understanding but was
this the understanding on the part of the experts when they answered or commented on this point?
Dr. Heather
10.233 Yes, it's my understanding that either dose or time could be varied but in my reading on this
topic and my experience, my contacts with colleagues who have worked in detail on it, I understand
it's most unwise to work towards the end of the spectrum on either time or dose.
Mr. Taylor
10.234 Yes, I agree certainly with Dr. Heather's comments. I would have thought that there might be
such a situation, if I could just mention a rather similar situation. In some countries cut flowers are
fumigated with methyl bromide and the dosage is metered in and I think there are situations where the
time would be fixed, but it may also be possible to monitor the concentration and a small amount of
gas is injected automatically, if necessary, in orde r to keep the concentration at the level required.
And I also mentioned earlier that this is certainly the sort of situation existing in flour mills, so as to
maintain the concentration that has been predetermined while keeping a fixed time. This was the way
I assumed that fumigation would probably be done but of course the time or the concentration could
be the variable factor. It would seem to me that fixing the time would be better, particularly if it's a

perishable commodity where time is relatively important and therefore, if possible, to have the
concentration as a variable and, as I've said, situations exist where automatic injection can take place
to maintain the concentration which has been calculated to be necessary.
Chairman
10.235 Dr. Ducom?
Mr. Ducom
10.236 I want to just add something. It may be not necessary to add some methyl bromide or to
increase the time. If by habit we know exactly for that variety or that commodity and that load, or
that packaging and so, we can maybe have the same kind of things we have now, I mean dosage at the
departure, but this dosage may be one time 48, for example, and one time - because it's another variety
or another boxes - it's 52 and so on without any change after but with checking CxT. Just what I
mean, it's not necessarily obliged to add some methyl bromide or time. We can adjust if you know
exactly the product and where we are working.
Chairman
10.237 Ok, thank you. The next question from Japan?
Japan (interpreted Mr. Sanatani)
10.238 The second question relates to the method described in question number nine. Is this relating
to the laboratory level or is this also including the commercial scale level or it refers to both
situations?
Dr. Heather
10.239 My expectation is that it would refer to the commercial operation, the operational situation
rather than laboratory although it may well be necessary to look at it first at the laboratory level, but it
would be an operational procedure.
Chairman
10.240 I understand that the question is does there exist commercial applications already now or only
on the laboratory level?
Dr. Heather
10.241 My knowledge is only with grain where I know the grain bulks are being fumigated by
monitoring the CxT product but I don't know of any fruit but that does not mean that that's not being
done because methyl bromide is not widely used for fruit in my country.
Chairman
10.242 Ducom?
Dr. Ducom
10.243 In fact, it's necessary to have a confirmatory test with CxT for one variety, exactly like with
insects. But for all other varieties at laboratory but maybe not six or seven or 14 apples, maybe much
more, but at the laboratory level could be done on all other varieties.

Chairman
10.244 Thank you. Now I turn back to Japan.
Japan (interpreted Mr. Sanatani)
10.245 What we are discussing here, if including the commercial scale level, then various conditions
are different such as the air tightness or methyl bromide dispersion speed and homogeneity. All these
conditions may differ between the laboratory vis-à-vis the commercial scale level. What's your
comment on these points?
Mr. Taylor
10.246 Yes, thank you for your question. I agree that they're may well be a number of variables,
certainly at the commercial level. Temperature may be a variable so it is something we should
certainly calculate into our design of dosing and I think one of the reasons why it might be necessary
to have some sort of monitoring coupled to an injection system is that, on a commercial scale, in order
to achieve the predetermined CxT product we would need to be able to take account of these
differences and, as I say, I know certainly in flour mills there are systems where automatic monitoring
and automatic dosing can take place. It would be possible to programme into the system such a
design that would take account of these differences such as you quite rightly mention, for example
leakage, which could account for losses which may vary from time to time, depending on the degree
of sealing attained in a chamber. One would hope that these losses would not be too great. But
certainly I think at the level of quarantine efficacy we might certainly need, if we were working on
CxT values, to be able to take account of these differences and an automatic system I hope would take
care of these variables. Thank you.
Chairman
10.247 Thank you Mr. Taylor. Any other comments to this? Dr. Ducom?
Dr. Ducom
10.248 Just one comment. Temperature is normally given. You have to work at a given temperature
but for gas-tightness of the chamber we can check before. The Japanese know that and USA too.
And for homogeneity we know that we can do that wi th fans adapted to the size of the chamber. We
can do that.
Chairman
10.249 Thank you, Dr. Ducom. Japan you have still the floor.
Japan (interpreted Mr. Sanatani)
10.250 This would be our last question. If the CxT value is one of the useful indicator of the efficacy
of fumigation I think Japan agrees to this in the ar g u m e n t s o f a r . H o w e v e r , w h e n i t c o m e s t o t h e
mode of action of methyl bromide it is not completely clarified yet, so besides the atmospheric
concentration of the fumigants which is described in the CxT value, there are other factors that would
affect the efficacy such as the structure of the surface and the contents. There are many unknown
factors. So we wonder if the CxT value alone could really guarantee the efficacy of the pest control.
This may attach upon very much of the expert matters so I would like to call on our expert to expand
on this.

Japan (interpreted Mr. Kawakami)
10.251 In case of the grain I understand the fumigation time duration is very long, or relatively long,
so that would take care of most of the problems and that's our understanding. But in case of fruits we
have to do the fumigation in a relatively short period of time and so that could produce some
problems and with regards to the pest insects inside of the fruits, besides the sorption we have to look
at the penetration factor as well. As mentioned earlier the surface structure and mode of action, how
they would interact or how those pests residing within inside of the fruit meat, how that and the
methyl bromide interact, so I would like the experts to share with us your knowledge on these matters.
Chairman
10.252 Thank you. Dr. Ducom?
Dr. Ducom
10.253 I cannot understand this mode of action problem. I don't know of any data on the problem
created by something you call mode of penetration. When we are working on CxT value, we are
working for efficacy. For example if we work the fifth instar larvae of codling moths, we can run that
with just one dose at the beginning or with the CxT value, and then we can do a confirmatory test with
that. It doesn't matter if the insect is inside and if the CxT inside the apple is different than the CxT
outside, the correlation between both is always the same. It's the same, for example, for wood to kill
an insect inside the gallery in the wood. It's always about, for example, for methyl bromide like 20 °,
it's 200 [grams per cubit meter] or something like that, but the CxT above, the ambient CxT must be
something like 1,000 to kill at 200 inside the gallery. It's the same for apples. I mean nevertheless it
doesn't matter if the insect is in the apple or outsi de, the CxT in the confirmatory tests will take take
into account. And the problem of surface in context I cannot understand. I cannot understand the
question. It was a question I would like to have asked before. I cannot understand the arguments and
I don't see any scientific data on that.
Chairman
10.254 Any other experts want to expand to this, or not? Ok, if that concludes the questions from the
Japanese delegation I now turn to the United States delegation. Do you have any follow-up questions
to this?
United States (Mr. Hirsh)
10.255 We've no follow-up questions.
Chairman
10.256 Thank you. Then I will take up one small question which the Panel still wants to present to
the experts and it is simply does anything in the apples study submitted by Japan, which was
discussed earlier during this day, change any of your earlier opinions as to the relevance of varietal
differences for quarantine efficacy? Dr. Heather?
Dr. Heather
10.257 I don't think there is anything in the apple study which impinges on this. Apples are unique in
that they have a combined treatment of cold and of methyl bromide and both of these are quite
efficacious in their own way. Perhaps I should say at this stage there was a question also from Japan
as to why I believe that apples would not differ very much amongst themselves varietally. The reason
for this is that cold treatment as a contributing tr eatment to the codling moth control does not have a
sorption problem so there should not be the same degree of variation between varieties of apples

because of this cold treatment factor that you would find in a treatment which relied only on methyl
bromide.
Chairman
10.258 Thank you very much. That was very useful for the Panel also. Dr. Ducom?
Dr. Ducom
10.259 Just one comment. This study was very interesting but the problem is that it was made on
apples, which were not at the same stage of storage because some were one month in storage and
others had three month's storage – so the variety is not the only factor which can change the value we
can read. So in practice that means that varieties may be a factor but maybe not very important and
maybe some other factors influence that data. The problem of all these studies is that they are just
descriptive studies. We take some apples, or peaches, or nectarines, and we look at the concentration
but the reason why it differs, we don't know. There is no fundamental work on that and we can just
say this works, or it does not work and so on.
Chairman
10.260 Ok, thank you. I now think that we can move to the concluding remarks by the experts and as
I promised I will give the floor alphabetical order, that means first to Dr. Ducom.
Dr. Ducom
10.261 Thank you Mr. Chairman. The work was very intensive, mainly for me because it's in
English. But I don't know if our work will be taken into account by both parties because the fact that
variety can or cannot be an important factor could be clarified just by studies and not only by talking
between people of good civility or something. A nd that's why it was important to talk about it, but
my feeling is that some study are to be made by US, I guess, or people who want to [export to] go in
Japan on each variety, something easy to do, and maybe Japan has to accept some rules. And the last
point, I am very, my concern is for example the last question they [Japan] ask for, if structure and
context makes a difference insects mode of action, that is new and for me it makes no sense and is a
problem for me.
Chairman
10.262 Thank you Dr. Ducom. Dr. Heather please?
Dr. Heather
10.263 Thank you Mr. Chairman. We are very fortunate, Mr. Taylor and myself, that Dr. Ducom's
name starts with a "D" so he has set the scene for us very well. The only comment that I would like to
add to that is one that methyl bromide is what I would like to call a very robust treatment. It has the
capacity, the reserve capacity, to overcome many small variations which will occur in operation.
Some of these may be fruit variations, others will be operational processes. This is why it has been
such a successful treatment over the years so in terms of the confidence which countries have in using
methyl bromide, it is a very good treatment. I think this needs to be taken into account and we should
not be too distracted, I think is the word I should use, about apparent differences in measurement of
some of the parameters that were involved because it is the overall efficacy that works and this has
been, I think, very well demonstrated in the large scale trials under discussion here and also on the
many other commodities that both Japan and the United States have worked on over the years. Thank
you.

Chairman
10.264 Thank you Dr. Heather. Mr. Taylor?
Mr. Taylor
10.265 Perhaps not for the record or for the minutes or whatever we're saying of this meeting, I find it
interesting that here I am talking about effectivene ss of methyl bromide, etc. when in the last three
countries I've been to in the last few weeks I've been talking about nothing but alternatives to methyl
bromide and trying to find alternatives which will allow us to phase out methyl bromide quickly and
easily, but this of course is not proving an easy task, and for the quarantine and pre-shipment use this
is going to be a very difficult task.
10.266 But coming back more to the situation at hand I think one of the things that has come out
from this meeting which I have found extremely interesting is that we do need more information
before we can say categorically that variety in fruit is a major factor affecting the efficacy of
treatment. I think we're all agreed that sorption is one of the major factors involved and, I think that,
as Dr. Ducom said earlier, one of the things that should be done is the testing of samples just with
methyl bromide [no insects to be involved] to s ee if we can determine the extent to which these
varieties do absorb methyl bromide. Also it would be nice to try and relate any differences we find to
chemical or physical characteristics more definitely.
10.267 And the other thing that I would like to sa y in conclusion that I found one of the most
interesting parts of the meeting came in question nine when the Panel asked us if, in that statement,
whether their understanding of what we were talking about was in fact the case. I think it is clear we
are saying here that if you have the right amount of gas for the right amount of time it will kill the pest
because basically that's what fumigation's all about. It doesn't matter which gas you're using. If you
have the lethal concentration for the required time this will kill the pest and that's really what we want
to try and achieve, so this long and somewhat co mplicated discussion about CxT products is in fact
very relevant because if we do achieve the desired CxT product in a commercial treatment we should
end up with an efficacious treatment which should satisfy the requirements for quarantine. I would
conclude there Mr. Chairman. Thank you.
Chairman
10.268 Thank you very much Mr. Taylor. I now proceed to the final set of questions by the Panel. I
would call this a confirmatory testing of the understanding of the Panel. However this is not a large
scale confirmatory test but just a small scale confirmatory test, and because these questions are all
phrased, yes, and I ask that this to be distributed to the experts so that you can look on them and also
to the parties, because these are phrased in a way that we ask for your confirmation of our
understanding, of course we would be most happ y if you could answer just "yes" but if our
understanding is not correct then of course you have to elaborate in which respect our understanding
has not been correct. And because these five questions are inter-linked we decided to distribute them
in writing for you because otherwise if we had presented them one by one the questions could have
been misunderstood. So I hope you take these five questions in combination, as linked together. And
I now give you some time to consider this. And you may of course discuss with each other if you can
reach a consensus reply.
[break]

Chairman
10.269 Ok, and I will read the questions one by one and ask your responses. And as to the parties
you will have the opportunity to comment on these questions and the answers tomorrow. Ok, first,
considering your responses to the Panel's questions it is the Panel's understanding that there are
differences which may be relevant for quarantine purposes between varieties of the products in
dispute, is this understanding correct? Dr. Heather?
Dr. Heather
10.270 My understanding, my belief is not that there are differences but there may be differences. I
don't believe that the occurrence of the differences has been proven and that they may be relevant for
quarantine purposes. So there are two sets of uncertainties in my mind in this statement. There's no
certainty that even if differences exist that they are relevant for quarantine purposes between varieties
of the products in dispute.
Chairman
10.271 Thank you. Dr. Ducom?
Dr. Ducom
10.272 Maybe, yes.
Chairman
10.273 Ok, Mr. Taylor?
Mr. Taylor
[Mr. Taylor gestured his confirmation of the other experts' answers]
Chairman
10.274 Ok, thank you. The second question is: It is also the Panel's understanding that the question
whether these differences are significant for quarantine purposes cannot be determined on the basis of
the evidence before the Panel. Do you agree?
Mr. Taylor
10.275 Yes.
Chairman
10.276 Dr. Heather?
Dr. Heather
10.277 Essentially yes, with the proviso of those double uncertainties that I referred to in the first
one.
Chairman
10.278 Ok, Dr. Ducom?

Dr. Ducom
10.279 Yes.
Chairman
10.280 Yes? Ok. Then the third question: To the extent that differences between varieties are
significant for quarantine purposes, is the Panel's understanding correct that they are mainly or even
exclusively related to different levels of sorption of the fruit? Dr. Heather?
Dr. Heather
10.281 Could I defer to the fumigation specialist on this one please?
Chairman
10.282 Ok. Of course. No need that everyone answers to every question, only within the limit of
your competence of course. Dr. Ducom?
Dr. Ducom
10.283 Yes. Just two points. The first, we don't need any insects and the second one, we can, we
must, we have to do that, at the time when the fumigation has to be made.
Chairman
10.284 Ok, thank you. Mr. Taylor?
Mr. Taylor
10.285 I agree.
Chairman
10.286 You agree. Thank you.
10.287 Now, the most lengthy question no. 4. In respect of the products at issue it is the Panel's
understanding that the degree of varietal differences which have an effect on quarantine efficacy may
vary between products. For instance, we have stated that methyl bromide is absorbed particularly by
oils and fats and that the oil content of walnuts which is a varietal factor has a significant effect over
sorption of methyl bromide. Hence it is the Panel's understanding that in the specific case of walnuts
varietal differences in respect of oil content may affect quarantine treatment to a greater extent than
varietal differences for the other products in dispute. Is this understanding correct? Dr. Heather?
Dr. Heather
10.288 Again on the effect of the oils I would like to defer to Mr. Taylor and Dr. Ducom. But could I
please raise the point that walnuts are unique amongst all the commodities which we have been
considering at this meeting. They have this oil problem which to my knowledge is not shared by any
of the fruits and so they are a commodity which needs to be differentiated against, rather than the
varietal problem.
Chairman
10.289 Thank you. Mr. Taylor?

Mr. Taylor
10.290 Thank you Mr. Chairman. Obviously the points that Dr. Heather just mentioned are very
relevant. And the distinct differences between the fruit and the walnuts, so in my view I would have
thought that the Panel's understanding of this situation is correct.
Chairman
10.291 Thank you. Dr. Ducom, do you want to add?
Dr. Ducom
10.292 Just to add that we have at least for walnuts the reason why the sorption exists and if we had
something like that for apples and nectarines we should be in a good way.
Chairman
10.293 Ok, thank you Dr. Ducom. And now the last question, it is also the Panel's understanding that
an added buffer of 10-20% will with a high probability cover any varietal differences of apples,
cherries and nectarines but that this may not be the case for walnuts. Is this understanding correct?
Dr. Heather?
Dr. Heather
10.294 Again, even for walnuts, the work was not done on a single variety, it was done on a number
of varieties so it's not just the 10-20%, it's also the fact that you had a spread of samples or
representation of walnuts as a commodity. Apart from that, yes.
Chairman
10.295 Ok. Dr. Ducom?
Dr. Ducom
10.296 Why not 30, 40, 5% like I said before? I mean,..
Chairman
10.297 ... No, 10-20 because that is what......
Dr. Ducom
10.298 Ok, but why not 10-20, why not? But the quest ion, the answer is that when question is
answered the question of 10-20 will be answered too? I mean we don't know if 10-20% [is high
enough], we can imagine it's large enough but there is no scientific proof of that. The only proof
could be to have some sorption data on other varieties to say, oh it's must too high and so on. In
practice 10-20 may work, but it may not work. It seems to work because all the data of the
confirmatory tests made by the USA work but we don't know for the rest.
Mr. Taylor
10.299 I have nothing to add to that.

Chairman
10.300 Thank you, Mr. Taylor. That concludes our session for today. I will once more thank very
much the three experts. Your contribution has been most helpful. I think that the Panel now can work
on a much more solid basis as to the scientific and technical facts which we have to take into account.
Of course now we have to go further and take into account the legal aspects. And that's our job, but
anyway, it is impossible to tackle the legal aspects without having a correct understanding of the
underlying scientific and technical issues. So once more very much thanks for your excellent
contribution, and I also want to thank the parties for their questions which have also facilitated the
understanding of the Panel of the relevant issues in this case and I invite the parties to the second
substantive meeting tomorrow morning at 10 o'cloc k and this will be in Room F. So Room F
tomorrow morning at 10 o'clock. Ok, thank you very much and the meeting is adjourned.