United States
                       Environmental Protection
                       Agency
Prevention, Pesticides
and Toxic Substances
(7508C)
EPA738-F-00-013
November 2000
SEPA   Oxamyl  Facts
               EPA has assessed the risks of oxamyl and reached an Interim Reregistration Eligibility Decision
         (IRED) for this carbamate pesticide.  With the risk mitigation measures required, oxamyl fits into its
         own "risk cup"-- its individual, aggregate risks are within acceptable levels.  Oxamyl also is eligible for
         reregistration, pending a full reassessment of the cumulative risks.
               Used on several vegetables, fruits, and non-
         food items, oxamyl residues in food and drinking
         water do not pose risk concerns for the general
         population. Although oxamyl showed potential
         aggregate risks to children (1-6 years), the Agency
         does not expect risks to children due to the rapid
         reversibility of cholinesterase inhibition.  Oxamyl has
         no residential uses, and fits into its own "risk cup."
         With required mitigation measures, oxamyl worker
         and ecological risks are believed to be significantly
         reduced.

               EPA's next step under the Food Quality
         Protection Act (FQPA) is to complete a cumulative
         risk assessment and risk management decision
         encompassing carbamate pesticides that share a
         common mechanism of toxicity. The interim decision
         on oxamyl cannot be considered final until this
         cumulative assessment is complete. Further risk
         mitigation may be required at that time.

               EPA is reviewing the carbamate pesticides to
         determine whether they meet current health and safety
         standards.  Carbamates need decisions about their
         eligibility for reregistration under FIFRA.  Additional carbamates with residues in food, drinking water,
         and other non-occupational exposures also must be reassessed to make sure they meet the new FQPA
         safety standard.

               The oxamyl interim decision was made through an abbreviated public participation process,
         which increases transparency and maximizes stakeholder involvement in EPA's development of risk
          The Carbamate Public Participation Process

                The carbamates are a group of related
         pesticides that affect the functioning of the nervous
         system.  EPA considers them a high priority for
         review under the Food Quality Protection Act.
                EPA encourages the public to participate
         in the review of the carbamate pesticides.  The
         Agency released the preliminary scientific risk
         assessments for review and comment earlier and is
         now releasing the revised scientific risk
         assessments for oxamyl and its interim
         reregistration decision. The Docket telephone is
         703-305-5805, or see EPA's web site,
         www.epa.gov/pesticides/reregistration/oxamyl/
                EPA is exchanged information with
         stakeholders and the public about oxamyl to
         address the uses and risks through stakeholder
         meetings, conference calls, and other fora. USDA
         coordinated input from growers and other oxamyl
         pesticide users.
                Based on current information from
         interested stakeholders and the public, EPA is
         making interim risk management decisions for
         individual carbamate pesticides, and will make final
         decisions through a cumulative carbamate
         assessment.

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assessments and risk management decisions. EPA worked with affected parties to reach the decisions
presented in this interim decision document.

Uses

       A systemic and contact insecticide/acaricide and nematicide, oxamyl is a restricted use
       pesticide used on apples, bananas, carrots, celery, citrus, cotton, cucumbers, eggplants, garlic,
       ginger, muskmelon (including cantaloupe and honeydew melon), onion (dry bulb), peanuts,
       pears, peppers, peppermint, pineapples, plantains, potatoes, pumpkins, soybeans, spearmint,
       squash, sweet potatoes, tobacco, tomatoes, watermelons, yams.  Oxamyl is also used on
       Non-bearing apple, cherry, citrus, peach, pear, and tobacco.

      Approximately 800,000 of oxamyl active ingredient (a.i.) are applied annually.  Although cotton
       accounts for most of the usage,  600 thousand pounds a.i. oxamyl is used on only 7 percent of
       total cotton acreage. Oxamyl is applied 1-2 times per season when it is used, usually at a rate
       of about 0.4 pounds a.i. per acre. For most other crops, oxamyl is generally applied 1 to 2
       times per season around 1 Ib. ai/A. Rates as low as 0.2 Ib ai/A may be used.

       There are no residential uses.

Health Effects

       Oxamyl can cause cholinesterase inhibition in humans; that is, it can overstimulate the nervous
       system causing nausea, dizziness, confusion, and at very high exposures (e.g., accidents or
       major spills), respiratory paralysis and death.
Risks
       Acute dietary risks from food and drinking water are below the level of concern for all
       segments of the population, except childrenl-6 years old.

       Chronic dietary risks were not assessed for oxamyl due to the rapid reversibility of ChEI.

       The Agency believes the acute aggregate (food and water) risks to children (1-6 years) is
       largely an overestimated risk concern because the assessment does not account for the rapid
       reversibility of ChEI, which occurs within 2 to 3 hours.  The Agency believes the results from
       an ongoing drinking water study will confirm the assessed risks.

       The current occupational assessment indicates risk concerns for all use scenarios at the current
       maximum label rate. Post-application risks for workers entering treated fields are generally not

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       of concern under the current restricted entry intervals (REI), except for hand-harvesting of
       citrus tree crops.

      However, the Agency believes that implementing the mitigation measures which includes rate
       reductions, engineering controls, additional personal protective equipment, and several
       voluntary cancellations will effectively reduce exposure and risk to a level that is not of concern
       to the Agency. The Agency is also increasing the REI for hand-harvesting of citrus tree crops
       and expects the risks to be reduced to level that is not of concern.

       There may be some acute and chronic risks to avian and mammalian species, as well as,
       potential concerns for endangered species of freshwater invertebrates.  However, the Agency
       believes that the mitigation measures summarized below and the "restricted" use classification
       will reduce potential ecological the risks and adequately mitigate risks.

Risk Mitigation

       To mitigate risks to handlers and workers:

               Reduce maximum aerial application rate to 1.0 Ib ai/A for foliar applications on all
               crops except cotton.
              Reduce maximum chemigation application rate to 2.0 Ib ai/A for all crops except
               cotton.
               Reduce maximum rate to 0.5 Ib ai/A for cotton, except for AZ and CA (1.0 Ib ai/A
               with closed systems); and reduce maximum seasonal rate to 3.0 Ib. ai/A/year.
              Reduce maximum soil application rate to 4.0 Ib ai/A for all crops, except mint and
               pineapple, which must be reduced to 2.0 Ib ai/A.
               Reduce seasonal maximum  applications for all crops to 8 per crop and incorporate all
               groundboom soil treatments by water or mechanical means.
              Require enclosed cockpits for aerial applicators and closed mixing/loading systems in
               CA and AZ for cotton use at 1  Ib. ai/A.
               Maintain PPE for all uses (baseline and coveralls, chemical resistant shoes, socks,
               chemical resistant gloves, chemical resistant apron, head gear for airblast, and an
               organic vapor respirator).

       Also, the registrant has decided to voluntarily cancel the following uses:

              Seed piece dip (yams).
               Soybean use.
               Soil broadcast treatment for cotton.

       To mitigate the ecological risks:

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              Measures mentioned above are expected to affect the ecological concerns.

Next Steps

      The oxamyl IRED is being issued in final (see www.epa.gov/REDs/ or
       www.epa.gov/pesticides/reregistration/oxamyll without a formal comment period.  The docket
       remains open, however, and any comments submitted will be considered in any future actions.

       To effect risk mitigation as quickly as possible, the Agency is requiring that all labels must be
       amended to include the above mitigation and submitted to the Agency within 90 days after
       issuance of this IRED.

       The registrant must submit the final results of the drinking water study by the year 2001.

      When the cumulative risk assessment for carbamates, including oxamyl is complete, EPA will
       issue its final tolerance reassessment decision for oxamyl and may require further risk mitigation
       measures. Similarly, the Agency may reconsider any part of this interim decision based on new
       information which may come to the Agency's attention.  The Agency will revoke fourteen
       tolerances because there are either no registered uses or because the commodity is no longer
       considered a significant feed item; and decrease three tolerances because available data
       supports the decrease. Raising/or establishing new tolerances will be considered once a
       cumulative assessment is completed.

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