US CUE16 Replies to MBTOC Final Page 1

NOMINATING PARTY : The United States of America

DATE: MARCH 20 , 201 4

FILE NAME: USA CUE16 STRAWBERRY FRUIT IN CALIFORNIA

AND HAM FACILITIES

BRIEF DESCRIPTIVE TI TLE : U.S. Response to M BTOC March 6 , 201 4 Questions on Strawberry Fruit and Ham Facilities

SITE NAME (OPEN FIEL D): Strawberry Fruit in California Dry Cured Meat Products

NOMINATING PARTY CONTACT DETAILS:

Contact Person: Federico San Martini, Ph.D.

Title: Foreign Affairs Officer

Address: Office of Environmental Policy

U.S. Department of State 2201 C Street, N.W. Room 2657 Washington, D.C. 20520 U.S.A. Telephone: (202) 647

- 3819

Fax: (202) 647

- 1052

E

- mail: SanMartiniFM@state.gov

CONTACT OR EXPERT(S) FOR FURTHER TECHNICAL DE TAILS:
Contact/Expert Person: Yu

- Ting Guilaran

Title: Director

Address: Biological and Economic Analysis Division Office of Pesticide Programs U.S. Environmental Protection Agency 1200 Pennsylvania Avenue, N.W. Mailcode 7503P Washington, D.C. 20460 U.S.A. Telephone: (703) 308

- 0 052

Fax: (703) 308

- 7042

E

- mail: Guilaran.Yu

- Ting@epa.gov

BACKGROUND The United States government nomination is for 3,240 kilograms of methyl bromide to fumigate aged country hams in 27 facilities and for 231,540 kilograms of methyl bromide to fumigate strawberry fruit fields in California

. In ham houses

, t he pest of concern is Tyrophagus putrescentiae, the ham mite (also called cheese mite and mold mite), which infests the aging

hams and renders them unsalable in the United States. No alternatives have yet been identified to control this pest under U.S. conditions though research into alternatives cont inues

. In California for strawberry fruit this nomination is for areas in California where a transition period

is needed for the use of broadcast 100% chloropicrin, in fields with high pest pressure, inUS CUE16 Replies to MBTOC Final Page 2

particular, with Macrophomina and Fusarium or where 1,3

- dichloropropene (1,3

- D) use is limited by township caps. This sector will complete its transition to alternatives by the end of 2016, in time for the 2017 use

- season

.

Strawberry Fruit MBTOC Question 1. The quantity of MB requested for 2015 is 373,660 Kg to treat 2198 ha. For 2016, this quantity has been reduced to 231,540 Kg for the treatment of 1,362 ha. What alternatives are used on the non nominated area (836 ha).

U.S. Reply Primarily 1,3

- dichloro propene and chloropicrin or straight chloropicrin at rates up to 392 kg/ha is used in these transitioned, non

- nominated areas. The transition from methyl

bromide has resulted from extensive work by California strawberry specialists and growers

to find the most effective rates, application methods, tarps, and other means of managing pests formerly managed by methyl bromide

. In addition, time was required for developing safe and effective procedures to use straight chloropicrin at the recently

- allowed higher use

rates. Non

- chemical means (e.g., ASD, steam) as described in the nomination are being studied, but not necessarily commercially used at present.

MBT OC Question 2

. What does the party mean by “ a shift in the production away from sensitive sites” Are these sites the full amount of the nomination for 2016 (Appendix 1)?

U.S. Reply

Sensitive sites include areas near schools, nursing homes, and residential developments

where due to recent label changes the use of fumigants would require larger buffers, lower rates, or additional methods to reduce soil emissions (different tarps or water seals). Th e U.S nomination is for areas where there is a cr itical need for methyl bromide to treat fields 1) where a transition period is needed for the use of broadcast 100% chloropicrin in fields with high pest pressure, in particular, with Macrophomina and Fusarium and 2) where 1,3

- D is limited by township caps and 3) are not new production areas

. Sensitive sites are a

subset of area where methyl bromide is a critical need.

Dry Cure d Pork

MBTOC Question 1. It is understood by MBTOC that previous research efforts in the US have partly focused on determining when and where the mite infestation come from in order to avoid their introduction onto the hams. Could you please clarify?

U.S. Reply

The ham mite is a domesticated pest that has adapted to living on human food in or near human habitats and it no longer has a “wild” habitat. In that regard

, the ham mite is like the German cockroach, house fly, Norway rat and other common cosmopolitan stored

- product

pests

. Research by Dr. Phillips at Kansas State University has developed a trap that can detect the presence of ham mites and monitor mite numbers over space and time to provideUS CUE16 Replies to MBTOC Final Page 3

information for pest control decisions. Despite the best efforts to minimize their introduction

such as sanitation, clearing areas around the ham houses, etc. mites are still found in ham

facilities

.

Rega rding the ultimate source s of mites with in a ham facility from year to year , they most likely are already living in non

- treated , or surviving i n poorly treated or difficult to treat

areas , or outside of the building. One would hope that early infestation of a new facility is

rare
, but when it does happen the mites were likely brought inside with shipments of food or transported on equipment that came from a mite

- infested area

. Even newly constructed

facilities have developed problems with mites ( see question 6).

MBTOC Question 2. Are the MB treatments of the ham houses sublethal in the first place so that surviving mites can attack again or are the mites continually exported from outside?

U.S. Reply Methyl bromide treatments are never intended to be sublethal since m ite s that escape a lethal dose of methyl bromide can multiply to be at pest status much faster than mites introduced from outside the facility. F acilities take precautions to e nsure effective fumigations (see question 3) ; the main source of introduction of mites is from the outside. New hams are continually introduced into the aging rooms and this proc ess allows for the introduction of new mites into the facility. Question 1 addresses the potential source s of

mite infestations. Current research is developing IPM tools so that ham facilities can become less dependent on regular fumigation, and work is also aimed at providing

effective methyl bromide alternatives that can be used when IPM determines a n effective fumigation is needed.

MBTOC Question 3. If survivors are the reason, is it possible to modify the treatment and possibly the internal construction of the houses?

U.S. Reply

H am producers are using the best sealing, fumigation, and IPM processes possible for control of mites. The reoccurring mite problem appears to be due to re

- introduction (see question 1)

. The best possible fumigation treatment occurs when there are continuous improvements to the application of the fumigant, to the structure, and practices of the applicators. The building being fumigated must be as gas tight as possible. Permanent sealing of certain structural components must be done, and temporary sealing with tape and

caulk needs to be well

- inspected and effectively applied before treatment. All closed spaces (e.g., clo sets, storage cabinets, stairwells, etc.) must be opened to allow gas to spread. The temperature should be 21 o C (70 o F) or warmer and gas concentrations should be remotely monitored at many locations within the building, high and low, so that more gas can be added remotely when/if concentrations drop before the treatment ends. U.S. dry

- cured ham producers make every effor t to follow these practices to minimize their need for and emissions of methyl bromide.

MBTOC Question 4. Has the party considered additional heat during the fumigation to help fully eradicate all present mites and stages?

U.S. ReplyUS CUE16 Replies to MBTOC Final Page 4

T he summer or agin g room (where the mite s are typically found) is typically held at approximately 29 o C (85 o F) which is generally considered a high temperature for fumigations

. Further i ncreasing the temperature in the curing or aging rooms will negatively impact the quality, taste and texture of the ham. Increasing the temperature for a short duration (72 hours) during the fumigation process has been shown to be beneficial in

some situations (e.g. flour mills, food processing plants, etc.)

. However, it would be very

difficult to heat up the ham facility without increasing the temperature in the curing and aging rooms. See description of curing process below.

Steps in the Curing Process

Step 1 (Winter Room)

-- Ham is typically salted and sugared using a dry rub method on Day 1 and Day 15. The temperature is approximately 3.3 o C ( 38 o F) with low humidity. Sometime between days 42

- 50, the salt and sugar are scraped and rubbed off of the ham.

The hams ar e then moved to the spring room. In this room, the high salt content and low

temperature is sufficient to keep insect pest pressure to a minimum.

Step 2 (Spring Room)

-- After being removed from the winter room, the hams are wrapped in cotton netting an d placed in the spring room for only 10

- 15 days before being

moved to the summer room . The temperature is approximately 10

- 13 o C ( 50

- 55 o F) at 50% humidity. The humidity is very important at this stage and it is monitored closely. Most hams are eq ualized in the spring room. Equalization is a process whereby the salt cure penetrates from the surface of the ham, through the skin, and to the inner portion of the ham. There are no insect problems here due to the low temperature and the limited

amount of time that the hams are in this room.

Step 3 (Summer or Aging Room)

– Hams are next moved to the summ er (or aging room) for up to 18 to 24 months . The temperature is maintained between 27

- 32 o C ( 80

- 90 o F) at 55% humidity. These conditions are very important to develop an intense, concentrated

flavor and aroma. As the ham ages, the moisture content of the ham will decrease, the salt content increases, and the chances of bacterial action become limited. I f desired, smoking of the hams may occur here, or in a separate “smoke house”. Since the temperature and humidity are higher in this room, conditions are ideal for pest pressure. It is at this stage that the application of methyl bromide is necessary.

MBTOC Question 5. Has a HACCP program been considered/implemented to av oid

reinfestation of the hams?

U.S. Reply The research discussed in question 1 was designed in part to better understand how mites are introduced into ham facilities. We plan to use the results of this and other research to implement a mite IPM plan as part of the Hazard Analysis Critical Control Point (HACCP)

program. HACCP is a systematic preventive approach to food safety required in certain

U

. S

. food industries. HACCP plans look at every possibl e process and location in a food plant that could allow entry of pathogens or otherwise cause unsaf e food or loss or spoilage of food, identify the critical points (place and/or time) in the process that a set

- back canUS CUE16 Replies to MBTOC Final Page 5

occur, and instil special monitoring or inspection at the critical point so that problems can be avoided or readily corrected.

For pr evention or resolution of ham mite problems

, the USDA

- funded research in Kansas and Mississippi aims to develop an integrated pest management, IPM, program specific for

the ham mite that can be incorporated into the HACCP plan

. IPM programs are like

HACCP programs , but HACCP is generally broader in its application to both food safety and pest management. Mite IPM that are currently used involve th o rough sanitation t o remove existing mite infestation s and food debris that can support mites, regular cleanin g of floors and shelves to reduce mites, possible application of residual pesticide sprays on floors, walls and other surfaces to kill mites walking across them, monitoring mite populations with traps, as well as monitoring temperature, lighting and relati ve humidity for conditions that are conducive to mites. When traps indic a t e that mites have reached an action threshold then fumigation must be done effectively. The IPM monitoring and sanitation can help to develop a pest HACCP plan for each facility th at may include high risk areas needing regular cleaning or certain rooms over others that tend to have more mite problems. The goal of the USDA supported research is to develop a soun d IPM program with effective eradication tools (e.g. fumigation with met hyl bromide alternatives) so that mites are kept well below the action threshold.

MBTOC Question 6. Has the party considered the construction of new ham houses that are modified so that mite infestation can be reduced and fumigation efficacy improved? Potentially control may be possible with the use of single isolated compartments that are used like

qua rantine compartments in the same plant. Is this possible and/or h as it been considered?

U.S. Reply Unfortunately, even the construction of a new plant or the use of separate storage rooms

has not prevented mite infestations. One new facility opened in 2 008 in Kentucky suffered

ham mite outbreaks the first year even when no old hams were moved into the facility. That particular facility has wall surfaces which are all washable, is securely sealed

, has concrete

floors , and does not hav e trees around the ne w facility

, all of which were not sufficient to eliminate mite outbreaks. However, the number of methyl bromide fumigations per year

has decreased from four to two and are applied only when mites are observed. Another

company in Virginia with separate st orage rooms has seen no difference in infestation

rates.

MBTOC Question 7. The US has previously presented to MBTOC the potential for protecting the ham pieces by enveloping them with mite proof enclosure like fine gauze. Has this technique progressed or been considered commercially?

U.S. Reply

Various studies have demonstrate d that fine mesh metal or nylon screening with openings less than 0.066 mm, but preferably less than 0.053 mm

, can exclude most to all mobile life stages of the ham mite, though a trial using such screens on dried hams to prevent mite

infestation has been planned but not yet undertaken . Recent funding from USDA will allow the Kansas group to test the potential for fine mesh screen to prevent mite infestation of clean ham pieces.US CUE16 Replies to MBTOC Final Page 6

However, even if an effective screening system is shown to be physically pos sible to protect individual hams

, the application of such a practice commercially will require additional process steps to be tested (e.g.

, wrapping the ham, ha ng ing without damaging the mesh, and the process of mesh removal without damaging the ham )

. In addition to the cost

of the m esh materi al , there are unknown additional processing costs and the possibility of unforeseen sanitation problems . Mite IPM and disinfestation would still need to be practiced in a l l facilities to manage mites that are not dir ectly on aging hams but rather on

food debris or other spaces. Future research will investigate such issues.

MBTOC Question 8. The CUN also mentioned that Phosphine tested in the laboratory was effective against all stages of mites within the label rate s of the fumigant and dried meats are already listed on the application label (page 5). Magnesium Phosphide was chosen over Aluminium Phosphide because it produces twice as much hydrogen phosphide but corrosion in electrical switches of fans, wirings and e quipment in the holding areas was present 21 days after fumigation. Future work needs to be done to address the corrosion problem (page 6).

U.S. Reply Yes, initial work on ham mite control determined that phosphine gas, hydrogen phosphide applied at 25 o C is very effective at controlling all stages of ham mites well within label application rates. However, phosphine gas by itself is corrosive to metals like copper,

silver

, and gold, and the so

- called metallic salt solid formulations that have ammonium

c ompounds generated along with phosphine are more corrosive than pure phosphine due to the ammonium compounds. T he high temperature and relative humidity in the summer

room are also potentially conducive to increased rates of corrosion. Techniques to prot ect
structures fr o m corrosion, as well as efficacy of non

- corrosive fumigants as alternatives to both phosphine and MB, are being researched now under the current USDA project in Kansas and Mississippi. See question 9 for future planned work

.

MBTOC Quest ion 9. What is your future plan to prepare ham production facilities for the corrosion potential of phosphine gas?

U.S. Reply

While t he scientists in the Kansas

- Mississippi collaboration are not experts in chemical

caused corrosion, discussions with fumigators experienced in phosphine and corrosion prevention suggest a course of action. Of the various formulation s of phosphine available

, the cylinder

- based gases should be the least corrosive. Thus either ECO 2 Fume TM , which is less than 2% phosphine wi th 98+% carbon dioxide, or VaporPhos TM , that quickly release s 99% phosphine and rapidly blends it with air

, will be used in trials at ham facilities. Cylinder

- based phosphine lacks the corrosive ammoniums and also can be quickly applied to the target conce ntration, and adjusted throughout the course of a fumigation to maintain desired doses. Additionally and very importantly, the building will be a carefully inspected by the experienced fumigators to locate all potential corrosion sites and then protect th ese from phosphine gas. Numerous techniques, such as bagging and positive

- ventilating

machines or protecting sensitive spaces with CO 2 , or coating electrical junctions with oils or other gas

- impermeable materials, will be used. The university researchers will work closely with special fumigators to carefully evaluate corrosion prevention and insecticidal improvements. A long

- term goal is to consult with industrial engineers and constructionUS CUE16 Replies to MBTOC Final Page 7

experts on ways to re

- engineer ham facilities to isolate sensitive metal fixtures from the fumigated spaces and to also provide guidance for new construction to be phosphine

- safe.

MBTOC Question 10. Similarly, has magnesium phosphide, which has proven to be effective in controlling all stages of mites, been considered for use in the aging rooms where electrical switches to the fans subjected to corrosion could be covered/protected?

U.S. Reply As p er question 8 and 9 above the U.S. researchers recommend that no metallic phosphide formulations be used in any ham facility, and if phosphine is chosen over other fumigants that guidelines developed for corrosion protection be us ed

.

MBTOC Question 11. In view of the research findings reported in the CUN, has the party considered a transition plan for this sector and what is it?

U.S. Reply The United States country ham producers continue to look for technically and economically

feasible alternatives fo r the control of mites. In addition to the research just cited, please

refer to the Critical Use Nomination for our research on non

- fumigant chemicals to control

ham mites. While significant progress has been made, t o date, such an alternative has not yet

been identified but we remain committed to continue our research efforts to find such

alternatives and to minimize emissions of and the need for methyl bromide.