−Summary of the Interim Report−
Nonylphenol

August 2003

National Institute of Technology and Evaluation
Study Group for Risk Assessment & Management of Nonylphenol

1.

Introduction

Nonylphenol (NP) is mainly used as binders for ink and an intermediate material for production of
nonylphenolethoxylate (NPE), which is one of the surfactants used in cleaning agents. And NP is also used
as intermediate of anti-oxidants for rubber. However, it is a substance that has raised public concern for its
toxic effect on fish and its suspected endocrine disrupting characteristics.
Given these concerns, international organizations such as the OECD and EU as well as domestic
governmental agencies have issued various assessment reports on the toxicity of NP, and a number ofindustries have taken voluntary actions to refrain from using NP where possible.
Therefore, it is an important task to gather scientific information so that appropriate management of NP
is implemented while not losing sight of its benefits. In order to achieve this goal, it is necessary to clarify
the current status of the production, use, and disposal of NP, the concentrations in the environment and thelevel of ecological risk in Japan, as well as to assess the risk in detail so that specific management measures
can be proposed.
In November 2001, the National Institute of Technology and Evaluation (NITE) established the Study
Group for Assessment and Management of Nonylphenol with the aim of gathering information. The groupconsists of experts from industry, academia and local government authorities.
The interim report includes the following information: information on the identification of NP; material
information such as physico-chemical properties; the results of the assessment of known hazards and therisk of NP as provided by domestic organizations (such as the Ministry of Economy, Trade and Industry(METI) and Ministry of the Environment (MOE)) and overseas organizations (such as EU, U.S.EPA,
Environment Canada, Health Canada); the amounts of NP produced, imported, and exported (from 1997 to
2001) and the amounts used by each industrial field and application (from 1995 to 2000); the amounts of
NPE produced, imported, and exported (2000) and the amounts used by each industrial field andapplication (from 2000 to 2001); concentrations of NP and NPE in the atmosphere, rivers (from 1998 to2001), and sediments of rivers (1998 to 2001); concentrations of NP in lakes, seawater, and undergroundwater (1998 to 2001); the environmental monitoring data on the concentrations of NP, NPE, andnonylphenoxycarboxylic acid (NPEC) in treated sewage water and sludge (1998 to 2001); Pollutant
Release and Transfer Register (PRTR) data on NP and NPE for 2001; the emission scenario that estimates
the amounts of NP and NPE released into the environment over their life cycles; estimation of theconcentrations of NP in rivers obtained from the water system exposure model that complements theenvironmental monitoring data; status of voluntary actions taken to NPE by related industries including theJapan Surfactant Industry Association; and case examples of actions taken to NP and NPE by Aichi
Prefecture and Osaka Prefecture.
Seven meetings of the Study Group have been held since November 2001, and invaluable data were
presented by the group members. It seems to contribute to risk assessment by collecting the necessary
information for the in-depth risk assessment.
This report summarizes the interim report prepared by the Study Group.

12.

General information

The interim report provides information on chemical identification, general information, and physicochemical properties, as well as the degradation pathway of NPE in the environment, since the main use of
NP is in the production of a surfactant, NPE.
NP is synthesized by the reaction of phenol with propylene trimers, giving para-substituted isomers as amajor product. NP has a melting point of -10℃, a boiling point of 293-297℃, and is a highly viscous liquidwith a light yellow color. When conducting risk assessment of NP, it is good practice to take into accountboth NP and NPE, since NP is the starting material and one of the resulting degradation products of NPE
after release into the environment.

3.

Existing reports on hazard and risk assessment

Results of hazard and risk assessment conducted in Japan and overseas are reviewed and summarized
below.
3.1 Existing Japanese assessment reports
3.1.1
Existing Japanese assessment reports
The following Japanese assessment reports are reviewed.
1) METI, Management Committee and Examination Committee of Chemical Substance Council (2002),
Hazard assessment of some chemical substances which have been “suspected to be endocrine
disrupters”
2) Chemicals Evaluation and Research Institute (CERI) (2002), Initial Risk Assessment Report for
Chemical Substances (A preliminary version) No.1, Nonylphenol (sponsored by NEDO)
3) MOE (2002), Study Group for Endocrine Disrupting Chemical Substances, “Report on the test resultsof the endocrine disrupting effects of nonylphenol in fish”
4) MOE (2002), ENVIRONMENTAL RISK ASSESSMENT OF CHEMICALS
3.1.2
Conclusions of the assessments
The following conclusions were reached in the assessment reports.
1) Individual assessment report by METI
No further testing is required at present for human health because enough information to identify theeffects of NP on the endocrine and reproductive system is available. Alternatively, risk reduction
measures based on the risk assessment shall be taken into account since NP shows reproductive anddevelopmental toxicities leaving endocrine disrupting effects out of consideration.
2) Initial Risk Assessment Report (A preliminary version) by CERI
The following conclusions regarding human health and the environment were reached:・In-depth risk assessment for human health are not necessary at present.
・It is necessary to conduct in-depth risk assessment for aquatic organisms in the environment based on
detailed information related to the effects on aquatic organisms and the behavior and concentrationsof NP and NPE in the environment.
3) Report on the test results of the endocrine disrupting effects of nonylphenol on fish by MOE
The following conclusion regarding the environment was reached:It is possible that NP may have some influence on the ecosystem through its endocrine disrupting
effects on fish in Japanese waterways.
4) ENVIRONMENTAL RISK ASSESSMENT OF CHEMICALS issued by MOE・The following conclusions regarding human health and the environment were reached:
No conclusion was reached regarding the effects on human health of drinking tap water and2

underground water.
There is need for an in-depth risk assessment for the freshwater environment, and for further
information on the seawater environment. It is possible that NP in seawater may have someinfluence on the environment.
3.2 Existing risk assessment reports compiled outside JapanThe following risk assessment reports were reviewed.
3.2.1
Risk assessment reports compiled outside Japan
1) European Union (EU) (2001), European Union Risk Assessment Report. 4-Nonylphenol (branched)and Nonylphenol.
2) USEPA (1996), RM-1 Document for para-nonylphenol.
3) Environmental Canada and Health Canada (2000), Canadian Environmental Protection Act, Priority
Substances List, Assessment Report, Nonylphenol and its ethoxylates.
3.2.2
Conclusions
The following conclusion regarding the environment was reached:
1) EU Risk Assessment Report (Extract of conclusion iii) applied to the surface water compartment
・There is a need for limiting the risks; risk reduction measures which are already being applied shallbe taken into account. This conclusion applies to the aquatic (surface water) compartment for thefollowing life cycle stages (as well as to regional concentrations derived from all sources):
・Production of NP;
・Production of phenol/formaldehyde resins;
・Production of epoxy resins;
・Production of other plastic stabilizers;
・Production of phenolic oximes;
・Production of NPE;
・Formulation of NPE; and・NPE use in all applications (i.e. agriculture; captive use by the chemical industry; civilengineering; electrical engineering; industrial and institutional cleaning; leather processing; metal
extraction and processing; mineral fuel and oil industry; paint production and use; photographic
industry; polymer industry; pulp, paper and board industry; textile industry).
2) US EPA RM-1 Document
・4-NP is acutely and chronically toxic to aquatic organisms. Overall, the risks due to acute andchronic effects on pelagic organisms do not appear to be widespread. But there are some impacted
areas where both pelagic and benthic organisms could be affected. This risk assessment only
addressed the risks of 4-NP. Although the parent, NP 1&2-EOs, and its degradated carboxylic acidare less toxic by at least an order of magnitude, in some areas there may be additive risk due to thepresence of all of the compounds.
・4-NP and the ethoxylates are weakly estrogenic.
・4-NP has a low to moderate bioconcentration potential in freshwater fish. There are reports of higher
BCF potential in marine fish and invertebrates.
・Although not readily biodegradable under laboratory condition, 4-NP is not as persistent as once
thought. This is based on actual measurements. Publicly Owned Treatment Works in the U.S. seemto have a very high efficiency in removing 4-NP.
3) Environmental Canada and Health Canada Priority Substances List, Assessment Report
・NP and its ethoxylates from untreated or partially treated textile mills that discharge directly to theaquatic environment occur at levels that are likely to cause harmful effects on aquatic organisms.
Additionally, discharges from municipal wastewater treatment plants and pulp and paper mills
3contribute NP and NPEs to the environment at levels that are of concern at a limited number of sites.
Although, based on current use and treatment practices, the risk to the aquatic environment of
NP/NPEs in municipal effluents is not high, the concentrations in the environment, especially nearoutfalls, may approach levels of concern.
・The potential for adverse effects due to exposure to NP/NPEs is generally associated with industrial
and municipal effluents in Canada. The increased use of NPEs or related alkylphenols in the future
could lead to more widespread concern for the effects of these chemicals. The use of NP/NPEs in
Canada, therefore, should be managed to minimize their exposure and threat to Canadianecosystems.

4.

Status of production and use

The production volume of NP in 2001 was 16,110 tons, of which 6,279 tons was exported, while 1,861
tons was imported. Production has been tending to decrease year by year.
Approximately 60% of the NP production is used in the production of surfactants (NPE). Approximately
40% is used in the production of anti-oxidants for rubber, phenol resins used in laminated sheets, the binder
for inks, and stabilizers for epoxy resins. NP was formerly used as an additive for plastics, but is not being
used for plastics produced in Japan at present.
The Study Group reviewed information on the use of NPE that may have effects on the ecosystem. NPE
is produced by the reaction of NP with ethylene oxide. In 2000, 26,127 tons of NPE were produced inJapan. Imports and exports were 532 tons and 13,147 tons, respectively. Domestic consumption was 13,512
tons used as a nonionic surfactant.
NPE is widely used in various fields of industry as a surfactant due to its excellent properties. In 2001,
about 2,700 tons of NPE were used as an emulsion polymerization and dispersing agent in the rubber andplastic industry, which is the largest user of NPE. About 2,100 tons were used as emulsifying agents for
cutting and rolling in the machinery and metal-working industry, while about 2,000 tons were used as aprofessional cleaning agent, and about 1,800 tons were used as a cleaning agent, lubricant, and level dyeing
agent in the textile industry. In addition to these major applications, NPE is used in various industrial fields
for such applications as a spreading agent for agricultural chemicals and fertilizers and a water reducing
agent in the construction and civil engineering industry. NPE has not been used in household detergents
since 1998 due to the voluntary actions implemented by industry.

5.

Environmental monitoring

The national government and local governments have measured the concentrations of NP and NPE in
local rivers and in water discharged from sewage treatment plants etc.
5.1 Concentrations in the atmosphere
Only a limited number reports on NP concentrations in the atmosphere are available. It may be possiblethat NP evaporates into the atmosphere where the concentration of NP in the surface water is high, but it israre for NP to be transferred to a remote place in the atmosphere. On the other hand, NPE does not easily
evaporate and the distribution ratio in the atmosphere is considered to be very low.
5.2 Concentrations in rivers
It was observed that the concentrations of NP and Nonylphnol n-ethoxylates (NPnEOs) in rivers tended
to decrease in the period from 1998 to 2000. NP had been detected at concentrations in a range of nd toseveral μg/L. Concentrations of NPE and NPEC were higher than those of NP. This indicates that the4released NPE is decomposed stepwise and generates intermediate products.
5.3 Concentrations in sediments in rivers
NP had been detected at concentrations in a range of nd to several thousands μg/kg, and NPE had been
detected at concentration in a range of several μg/kg to several tens μg/kg in river sediments. The
concentrations of NP tend to be higher than those for NPnEOs (n＝1 to 4).
5.4 Concentrations in lakes, seas, and underground water
The concentrations of NP in lakes were nd to 0.2μg/L in 2000, with a trend towards decreasing
concentrations in the period from 1998 to 2000.
The concentrations of NP in seas were nd to 0.1μg/L in 2000, and concentrations have been gradually
decreasing in the period from 1998 to 2000.
The number of underground water samples in which NP was detected decreased in the period from 1998
to 2000, and it was not detected at all in the 25 sampling spots in 2000.
5.5 Concentrations in treated sewage water and sludge
In treated sewage water, NP was detected at concentrations in a range of nd to several μg/L, and
NPnEOs (n=1 to 4) were detected at concentraitons in a range of nd to several tens μg/L. The
concentrations of NPnEOs (n=1 to 4) were higher than those of NP at many sewage treatment plants.
During the sewage treatment process, NPEC was found to be generated from NPE.

6.

PRTR data

6.1 Outline of the releases and transfers of NP
The total for releases and transfers reported by 116 facilities in 30 prefectures which produce, process or
use NP was approximately 160,000 kg in FY2001. The breakdown of the total is 538 kg discharged to theatmosphere, 2,484 kg into public water systems, 4 kg to the soil, 156,640 kg transferred off-site as waste
and 20 kg transferred to sewage.
The estimate releases of outside notification were 11,203 kg from listed industries (i.e. from small andmedium enterprises (SME)).
6.2 Outline of the releases and transfers of NPE
The total for releases and transfers reported by 411 facilities in 39 prefectures which produce, process or
use NPE was about 1,196,521 kg in FY2001. The breakdown of the total is 11,396 kg discharged to theatmosphere, 295,196 kg into public water systems, 4 kg to the soil, 606,415 kg transferred off-site as waste
and 282,772 kg transferred to sewage.
The estimate releases of outside notification were 729,488 kg/y from listed industries (i.e. from SME),
946,899 kg from non-listed industries and 83,931 kg from households in a total of 47 prefectures.

7.

Emission Scenario

An emission scenario for NP and NPE was developed based on the data which are the amounts of use by
applications obtained from NP manufactures and Japan Surfactant Industry Association (JSIA) described in
Chapter 4 and PRTR data described in Chapter 6 in order to estimate the amount released into water at eachstage of the life cycle, including production, formulation, and use.
Two methods were employed to estimate releases of NP and NPE.
One was estimation of the amounts of release to water using emission factors based on the expert
5judgment and applying the factors to the amounts of use by applications obtained from NP manufactures
and JSIA.
Another was estimation of the amounts of release to water by redistributing PRTR data by industry
categories to the applications set by JSIA.
The table below shows the amounts of NP and NPE released into water estimated by these two methods.
Table Amounts of NP and NPE shipped by application
and amounts used and released into water bodies
Amount released

Life cycle stage, applications

Amountused
in 2001(tons)

Method 1

notification

outsidenotification＊

16,1100.00030.003

0formulation and processing

6,400＊＊−

2

11

production

14,455

−

0.6

0

−

0.6

−

NPE

formulation and processing

Products
containing
NPE

Method 2(PRTR data)

production

NP

Industrialuse(tons/y)Rubber and plastics industry
Machinery and metal-working
industry
Textile industry
Industrial & Institutional
cleaners＊
Agricultural chemical industry(biocide, fertilizer, andfeedstuff etc)＊
Civil engineering andconstruction industry
Paint and ink industry

2,726

30

0.04

86

2,136

23

20

38

1,853

20

60

250

2,068

870

−

550

983

410

−

410

912

10

0.09

4.4

798

0

0

1.7

Laundry industry

577

240

3

230

Paper and pulp industry

548

6.0

200

4.1

Leather industry
Cosmetic and pharmaceuticalindustry＊
Petroleum and fuel industry

287

3.2

2

1.1

252

110

−

73

198

0

0.005

20

Food industry

175

1.9

−

1.3

IT-related industry

48

0.53

−

−

Environmental preservation

17

0.19

−

−

Others

877

9.6

0.8

91

* It is assumed that all the estimate releases of outside notification from listed and non-listed industries are made into
aquatic environments.
** FY2000−: Not investigated.
(NP: nonylphenol, NPE: nonylphenolethoxylate)6By comparing the amounts of release of NP and NPE obtained by the two different methods, it is seenthat there are large discrepancies between the results of rubber and plastic industry; civil engineering andconstruction industry; Laundry industry; and paper and pulp industry. This means that further investigationof facts is required to obtain more accurate estimation for the amounts of release.
Since the comparison between the amounts used by applications and those of release shows that theratios of release from the paper and pulp industry; I & I cleaners; agricultural chemical industry andcosmetics and pharmaceuticals industry are high, it is necessary to further investigate the actual status of
use in these applications depending on the effects of NP and NPE on the environment.
In addition, it is further necessary to elucidate the conditions of NP and NPE at sewage treatment plants
and waste treatment sites to clarify the total life cycle of these substances.

8.

Concentration calculation using models

Since the observation sites and actual observation times are limited for NP exposure data, the data thathave been gathered are not sufficient for the ecological in-depth risk assessment. In order to save labor andcosts required for large-scale monitoring, analysis using a computer model (AIST-SHANEL) has been
undertaken in an attempt to estimate the concentrations of NP in the aquatic environment.
The distribution of NP in the Tama River was analyzed in detail from geographical and seasonal
perspectives, revealing that estimated NP concentrations using the computer model were higher thanobserved concentrations, indicating that some modifications to the parameters are required.

9.

Voluntary actions taken by industry

Since there are concerns about the risk NP poses to the aquatic environment, Japanese industries havetaken voluntary actions to replace as much NPE as possible with polyoxyethylene alkyl ether (AE). Suchefforts will result in limiting the use of NPE only for those applications for which there is no substitutebecause of its beneficial properties.

10.

Case examples of actions taken by local governments

Actions taken by the local governments in Aichi and Osaka have been reviewed as case examples. Bothlocal governments continue to monitor the concentrations of substances, including NP, in surface water andin sediments because these concentrations were found to be high in the investigation conducted by thecentral government.
The Aichi prefectural government has established a policy based on the results of own investigation andthe views of MOE. In accordance with the policy, Aichi prefectural government continues to monitor
concentrations in the environment as well as compiling scientific information by gathering data fromgovernmental institutes and other organizations. In particular, the Aichi prefectural government has taken aleadership role with respect to business firms located along the Nikko River, where NP was detected at
higher concentrations in the study of 1998, in order to reduce the use of surfactants containing NPE and to
replace NPE with other feasible substitutes.
In the meantime, the Osaka prefectural government is gathering information on endocrine disruptors andis cooperating with the central government in a nationwide study. The Osaka prefectural government also
intends to ascertain the facts about releases of NP and NPE by utilizing the PRTR data, and to takemeasures to keep NP concentrations in the aquatic environment lower than the predicted no effectconcentration, if necessary.

7

—Summary of the interim report—
Nonylphenol
August 2003: 1st printing of 1st edition in JapaneseNovember 2007: Translating Japanese to English

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