METHYL BROMIDE CRITICAL USE RENOMINATION FOR POSTHARVEST -- DRY CURED PORK PRODUCTS

NOMINATING PARTY: The United States of America

FILE NAME USA CUN12 POST HARVEST -- DRY, CURED PORK PRODUCTS

BRIEF DESCRIPTIVE TITLE OF NOMINATION: 

Methyl Bromide Critical Use Nomination for Post Harvest Use on Dry Cured Pork Products 

(Submitted in 2010 for 2012 Use Season) 

STRUCTURE, COMMODITY OR OBJECT TREATED: 

This sector is for the production of cured meat products, such as country hams. These are 

produced primarily in the southern U.S. This sector has no known viable alternative currently 

available. 

QUANTITY OF METHYL BROMIDE REQUESTED IN EACH YEAR OF 

NOMINATION: 

TABLE 1: QUANTITY OF METHYL BROMIDE REQUESTED IN EACH YEAR OF NOMINATION

YEAR NOMINATION AMOUNT (KILOGRAMS) 

2012 3,730 

(Details on this page are requested under Decision Ex. I/4(7), for posting on the Ozone Secretariat website under 

Decision Ex. I/4(8).) 

In assessing nominations submitted in this format, TEAP and MBTOC will also refer to the original nomination on 

which the Party’s first-year exemption was approved, as well as any supplementary information provided by the 

Party in relation to that original nomination. As this earlier information is retained by MBTOC, a Party need not 

re-submit that earlier information. 

NOMINATING PARTY CONTACT DETAILS:

Contact Person: John Thompson 

Title: Division Director 

Address: Office of Environmental Policy 

 U.S. Department of State 

 2201 C Street, N.W. Room 2658 

 Washington, D.C. 20520 

 U.S.A. 

Telephone: (202) 647-9799 

Fax: (202) 647-5947 

E-mail: Thompsonje2@state.gov 

Following the requirements of Decision IX/6 paragraph (a)(1) United States of America has determined that the 

specific use detailed in this Critical Use Nomination is critical because the lack of availability of methyl bromide for 

this use would result in a significant market disruption. ■ Yes  No 

USA CUN12 POST HARVEST -- Dry, Cured Pork Products Page 1 
 

Signature Name Date 

Title: 

CONTACT OR EXPERT(S) FOR FURTHER TECHNICAL DETAILS: 

Contact/Expert Person: Jack Housenger 

Title: Division 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) 308-8200 

Fax: (703) 308-7042 

E-mail: Housenger.jack@epa.gov 

 

LIST OF DOCUMENTS SENT TO THE OZONE SECRETARIAT IN OFFICIAL NOMINATION PACKAGE: 

1. PAPER DOCUMENTS: 

Title of paper documents and appendices 

No. of pages Date sent to Ozone 

Secretariat 

USA CUN12 Post Harvest Dry, Cured Pork Products 

2. ELECTRONIC COPIES OF ALL PAPER DOCUMENTS: 

*Title of each electronic file (for naming convention see notes above) 

No. of 

kilobytes 

Date sent to Ozone 

Secretariat 

USA CUN12 Post Harvest Dry, Cured Pork Products 

* Identical to paper documents 

USA CUN12 POST HARVEST -- Dry, Cured Pork Products Page 2 
METHYL BROMIDE CRITICAL USE RENOMINATION FOR POSTHARVEST -- DRY CURED PORK PRODUCTS

1. SUMMARY OF NEED FOR METHYL BROMIDE AS A CRITICAL USE 

Currently there are no viable alternatives to methyl bromide for the dried meat industry: heat 

would alter the product, and phosphine may not control mites, a major pest. Sulfuryl fluoride 

received federal registration and has been tested for efficacy against the mites and other pests of 

cured meat products. Although mortality of the red-legged ham beetle occurred at levels below 

maximum rates of sulfuryl fluoride, the same cannot be said for the ham mites (Phillips, et al., 

2008). Control of the ham mites took three times the legal limits of sulfuryl fluoride (Phillips, et 

al., 2008). At the time of this nomination there are no known registered alternatives for use on 

hams in the U.S. that provide the same level of pest control as methyl bromide. 

This industry is cooperating with university researchers to find technically and economically 

feasible alternatives to methyl bromide. In the meantime, this industry is using IPM techniques 

to manage their pest populations. All use sanitation to keep their curing facilities clean. Several 

companies have modified their buildings to make them more gas-tight. Some companies are 

eliminating grass, trees, and shrubs from their buildings and replacing it with gravel, as 

suggested by researchers last year. Many use pheromone traps; however, these traps only used 

for monitoring purposes at this time (Arthur and Phillips, 2003). 

This industry currently has no viable chemical alternative available. Although its IPM measures 

may have reduced the number of times fumigation is needed in some facilities, it has not 

eliminated the need for fumigation. Therefore, methyl bromide remains critical to this industry. 

TABLE 2. NOMINATION AMOUNT 

 Gwaltney of 

Smithfield 

National Country 

Ham Association 

 Nahunta Pork 

Center 

American Assoc. 

of Meat 

Processors 

 Sector Total / 

Average 

Quantity Requested for 2011: Amount (kgs) 709 726 91 2,204 3,730 

Quantity Recommended by 

MBTOC/TEAP for 2011 : Amount (kgs) 709 726 91 2,204 3,730 

Amount (kgs) 709 726 91 2,204 3,730 

Volume (1000 m3) 42 56 5 110 213 

Rate 17 13 19 20 18 

Transition from 2011 Baseline 

Adjusted Value Percentage (%) 0% 0% 0% 0% 0%

Amount (kgs) 709 726 91 2,204 3,730 

Volume (1000 m3) 56 42 5 110 213

Rate 17 13 18 20 18

HAM

Quantity Approved by Parties for 

2011:

Quantity Required for 

2012 Nomination:

SECTOR

USA CUN12 POST HARVEST -- Dry, Cured Pork Products Page 3 
2. SUMMARIZE WHY ALTERNATIVES ARE NOT FEASIBLE 

This industry currently has no known viable chemical alternative available. Although its IPM 

measures may have reduced the number of times fumigation is needed, it has not eliminated the 

need for fumigation. Therefore, methyl bromide remains critical to this industry. 

3. RESEARCH RESULTS SHOWING EFFICACY OF ALTERNATIVES 

Researchers are investigating control of the arthropod pests on dry cured pork products. In the 

spring of 2007 a proposal was submitted to USDA CSREES Integrated Research, Education, and 

Extension Competitive Grants Program- Methyl Bromide Transitions by several meat scientists 

and an entomologist. This proposal was funded for the next three years. 

There are several objectives to this multiple year research program: First is to determine the 

effectiveness of chemical controls (sulfuryl fluoride, phosphine, and methyl bromide) against all 

life stages of both mold mites (Tyrophagus putrescentiae) and red legged ham beetles (Necrobia 

rufipes). Second objective is to determine the effectiveness of carbon dioxide and ozone against 

all life stages of both mold mites and red legged ham beetles. The third objective is to test the 

effects of sulfuryl fluoride, phosphine and methyl bromide on the quality and safety of the dry 

cured hams. The fourth objective is to conduct an economic analysis of the alternatives 

demonstrated to be technically viable alternatives for methyl bromide in this industry. 

The results of sulfuryl fluoride efficacy investigations on Tyrophagous putrescentiae, ham mite, 

and Necrobia rufipes, red-legged ham beetle, were presented at the 2008 MBAO Conference, in 

Orlando, Fl. The studies included eggs and a mixture of adults and large nymphs of mites and 

the eggs, large larvae, pupae and adults of beetles. The experiments were conducted for 48 hours 

at 23° C at various concentrations of sulfuryl fluoride. The investigators achieved 100% 

mortality of red-legged ham beetle adults and pupae at about 4.0 g/m3

, 100% mortality of larvae 

at 5.7 g/m3

. Eggs of red-legged ham beetles died at 24.0 g/m3 of sulfuryl fluoride, well below 

the maximum label rate (Phillips, et al. 2008). Mortality of ham mites required much higher 

concentrations of sulfuryl fluoride. A concentration of about 100.3 g/m3

 was necessary to obtain 

100% mortality of adults and nymphs under the test conditions. However this concentration 

obtained only a 95% mortality of mite eggs. This is about three times the legal label rate 

(Phillips, et al. 2008) and thus indicates that sulfuryl fluoride is not a viable alternative to methyl 

bromide for controlling ham mites. 

The results of carbon dioxide, phosphine, methyl bromide and ozone efficacy investigations on 

Tyrophagous putrescentiae, ham mite, and Necrobia rufipes, red-legged ham beetle, were 

presented at the 2009 MBAO Conference, in San Diego, CA (Sekhon, et al. 2009a, b; Phillips, 

2009). The studies included eggs and a mixture of adults and nymphs of mites and eggs, large 

larvae, pupae and adults of beetles. The experiments were conducted for variable times at 23° C 

at various concentrations of carbon dioxide, phosphine, methyl bromide and ozone. The 

investigators achieved mortality of all life stages of mites with a concentration of 60 % carbon 

dioxide with 144 hr of exposure (Sekhon, et al. 2009a; Phillips, 2009). However, fumigation 

with carbon dioxide would likely not be applicable since ham structures are not air-tight and 144 

USA CUN12 POST HARVEST -- Dry, Cured Pork Products Page 4 
hr is too long of a time to fumigate the hams. In addition, a carbon dioxide concentration (> 80 

%) with an exposure time of 144 hrs was necessary to cause 100 % mortality for all life stages of 

red legged ham beetles (Sekhon, et al. 2009a; Phillips, 2009). Investigators achieved 100 % 

mortality of all life stages of red legged ham beetles and ham mites with 48 hours exposure of 

400 and 1000 ppm of phosphine, respectively (Sekhon, et al. 2009b; Phillips, 2009). In addition, 

residual phosphine concentrations in dry cured hams that were fumigated for 48 hrs at 1000 ppm 

were below 0.01 ppm, the legal residual limit in stored food products (Sekhon, et al. 2009b), and 

consumer panelists could not detect differences between control and phosphine fumigated 

samples at 1000 ppm (Sekhon, et al. 2009b). Therefore, phosphine can now be considered a 

potential alternative to methyl bromide for controlling arthropod pests of southern dry cured 

hams. However, phosphine fumigation needs to be evaluated at the plant level to evaluate its 

effectiveness and economic feasibility in real world applications. In addition, phosphine has 

some potential shortcomings such as corrosion of metal and potential pest resistance by mites 

which could lead to an increase in required concentrations and exposure times when compared to 

laboratory testing. Phosphine is also not currently registered for use with dry cured hams so 

registration would need to be approved before it could be used by the industry. Ozone also 

showed potential for use as a fumigant. Ozone concentrations of greater than 150 ppm for 48 hrs 

were able to achieve 100 % mortality of ham beetles and mites at the bench top level (Sekhon, et 

al. 2009b; Phillips, 2009). Consumers also could not determine sensory differences between 

control hams and those that were fumigated with ozone at 175 ppm for 48 hrs (Schilling, 2009). 

However, ozone is not able to penetrate surfaces and therefore may not work well in real world 

applications since ham mites could potentially penetrate into meat surfaces and ham beetles bore 

through the meat tissue. Therefore, further testing needs be conducted at the plant level to 

determine if ozone can be considered a potential alternative to methyl bromide. Ozone is also an 

effective sanitizer and would benefit processors as part of their integrated pest management 

program since it would sanitize areas in the plant as well as equipment that could potentially 

harbor bugs and pathogens. 

Researchers also tested the efficacy of methyl bromide against ham mites and red legged ham 

beetles. Researchers determined that concentrations lower than 15 g/m3

 could be used to achieve 

100 % mortality of all life stages for red legged beetles and levels less than 8 g/m3

 could be used 

to achieve 100 % mortality in all life stages of ham mites at the bench top level (Sekhon, et al. 

2009b; Phillips, 2009). This reveals that fumigation levels should be tested at the plant level to 

determine if levels could be decreased from the 24 g/m3

 that is commonly used in the industry. 

This may not be possible at the plant level since many buildings are not air tight but should still 

tested to attempt to reduce methyl bromide use as much as possible. 

One alternative that could be investigated is the method reported from Spain on dipping infested 

hams into a mixture of hot lard and oil at 90o C. U.S. researchers will need to receive more 

details on the methods for oil dipping and then design an experimental protocol to address this 

for efficacy against ham mites and ham beetles, and also for any adverse effect against ham 

products. 

4. REGISTRATION UPDATE 

No new chemicals have been registered nor de-registered since the last nomination. 

USA CUN12 POST HARVEST -- Dry, Cured Pork Products Page 5 
USA CUN12 POST HARVEST -- Dry, Cured Pork Products Page 6 

5. ECONOMIC INFEASIBILITY OF ALTERNATIVES 

An economic analysis was not conducted because this sector has no technically feasible 

alternatives at this time. 

CITATIONS 

Arthur, F. and T. W. Phillips. 2003. Stored-product insect pest management and control, In: 

Food Plant Sanitation eds: Y. H. Hui, B. L. Bruinsma, J. R. Gorham, W. Nip, P. S. Tong, and 

P. Ventresca. Marcel Dekker, Inc., New York, pp. 341-358. 

Phillips, Thomas W., Md. Mahbub Hasaan, M. Jamie Aikins, and M. Wes Schilling. 2008. 

Efficacy of sulfuryl fluoride to control ham mites and red-legged ham beetles. Presentation 

at MBAO, Orlando, Fl. November 12, 2008. 

Phillips, T.W. 2009. Personal Communication. 

Schilling, M.W. 2009. Personal Communication. 

Sekhon, R.K., Schilling, M.W., Phillips, T.W., Hasan, M.M., Aikens, M. J., Mikel, W.B. 2009a. 

Chemical Composition of dry cured hams fumigated with carbon dioxide. 

Sekhon, R.K., Schilling, M.W., Phillips, T.W., Hasan, M.M., Aikens, M.J., Mikel, W.B. 2009b. 

Chemical Composition of dry cured hams fumigated with phosphine.