United States Prevention, Pesticides EPA 738-F-00-16

Environmental Protection and Toxic Substances October 2000

Agency (7508C)

 

Propetamphos Facts

EPA has assessed the risks of propetamphos and reached an Interim Reregistration Eligibility

Decision (IRED) for this organophosphate (OP) pesticide. Provided that the risk mitigation measures

outlined in this document are adopted, propetamphos fits into its own “risk cup”; that is, its aggregate

risks are within acceptable levels. Propetamphos is also eligible for reregistration, pending a full

reassessment of the cumulative risk from all OPs. 

Propetamphos is an insecticide used indoors

for the control of insects, such as ants, cockroaches,

fleas and termites. Propetamphos residues in food

and drinking water do not pose risk concerns. 

Additionally, risks are low to workers who mix, load,

and apply propetamphos at commercial and

residential use sites. There are also no environmental

risk concerns. However, there are post-application

risk concerns for adults, and especially children

entering areas treated with propetamphos. With

mitigation canceling all residential use, propetamphos

fits into its own “risk cup”. With other mitigation

measures, propetamphos’ worker risks also will be

below levels of concern for reregistration.

EPA is reviewing the OP pesticides to

determine whether they meet current health and safety

standards. OPs need decisions about their eligibility

for reregistration under FIFRA. Additional OPs with

residues in food, drinking water, and other nonoccupational exposures also must be reassessed to

make sure they meet the new Food Quality

Protection Act (FQPA) safety standard. 

EPA’s next step under the Food Quality Protection Act (FQPA) safety standard is to complete

a cumulative risk assessment and risk management decision encompassing all the OP pesticides, which

share a common mechanism of toxicity. The interim decision on propetamphos cannot be considered

final until this cumulative assessment is complete. Further risk mitigation may be necessary at that time. 

The OP Pilot Public Participation Process

The organophosphates are a group of

related pesticides that affect the functioning of the

nervous system. They are among EPA’s highest

priority for review under the Food Quality Protection

Act. 

EPA is encouraging the public to

participate in the review of the OP pesticides. 

Through a six-phased pilot public participation

process, the Agency is releasing for review and

comment its preliminary and revised scientific risk

assessments for individual OPs. (Please contact

the OP Docket, telephone 703-305-5805, or see

EPA’s web site, www.epa.gov/pesticides/op .)

EPA is exchanging information with

stakeholders and the public about the OPs, their

uses, and risks through Technical Briefings,

stakeholder meetings, and other fora. USDA is

coordinating input from growers and other OP

pesticide users. 

Based on current information from

interested stakeholders and the public, EPA is

making interim risk management decisions for

individual OP pesticides, and will make final

decisions through a cumulative OP assessment.
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The propetamphos IRED was made through the OP pilot public participation process, which

increases transparency and maximizes stakeholder involvement in EPA’s development of risk

assessments and risk management decisions. EPA worked extensively with affected parties to reach

the decisions presented in this IRED document, which concludes the OP pilot process for

propetamphos. 

Uses

• Propetamphos is an OP insecticide used indoors for the control of insects, primarily ants,

cockroaches, fleas, and termites. Propetamphos may be applied at indoor residential, medical,

commercial, and industrial buildings and equipment, such as homes, apartments, stores, schools,

hospitals, offices and factories. It may also be used in food service establishments where there

is no contact with food, and where no processing, packing, or warehousing of food occurs. 

• Total annual usage is low, and estimated at 90,000 pounds active ingredient. The typical rate of

dilution varies from 0.5% to 1.0% active ingredient solution. Propetamphos is applied as a

water dilution through a compressed air sprayer, often with a low pressure hand wand.

Health Effects

Propetamphos 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 

• Dietary exposures from food are not of concern for the entire U.S. population, including infants

and children, provided food is removed or covered prior to an area being treated. Because

propetamphos is only used indoors, exposure from drinking water sources is not expected. 

• Risks are low, but still of concern for workers who mix, load, and apply propetamphos at

commercial and residential use sites.

• Risks are of concern for adults, and especially children, from combined dermal, inhalation, and

(for children only) oral routes of post-application exposure from re-entering areas treated with

propetamphos.

• Because propetamphos is used indoors, exposure to the environment is not expected, and

therefore, ecological risks are not of concern to the Agency.

In order to support an IRED for propetamphos, the following risk mitigation measures are

necessary:
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• To mitigate dietary (food) risks:

• for use in food service establishments, all food must be either covered or removed prior

to the area being treated.

• To mitigate worker risks:

• reduce the maximum rate of dilution from 1.0% to 0.5% active ingredient solution;

• applicators must wear personal protective equipment consisting of a long-sleeve shirt,

long pants, shoes and socks, and chemical-resistant gloves; and 

• only protected handlers may be in the area during applications.

• To mitigate non-occupational risks to persons re-entering treated areas (post-application risks):

• cancel all residential uses;

• prohibit use in structures children and the elderly occupy, such as or including homes,

schools, day-cares, hospitals, nursing homes (except for areas of food service when

food is covered or removed prior to treatment);

• cancel all spot, broadcast, and termiticide treatment; and 

• restrict the method of application to crevice treatment only, as defined in OPPTS

860.1460 Food Handling.

Next Steps

• Numerous opportunities for public comment were offered as this decision was being

developed. The Propetamphos IRED, therefore, is issued in final (see www.epa.gov/REDs/ or

www.epa.gov/pesticides/op ) without a formal public comment period. The docket remains

open, however, and any comments submitted in the future will be placed in this public docket.

• To effect risk mitigation as quickly as possible, time frames for making the changes described 

in the Propetamphos IRED are shorter than those in a usual RED. All labels need to be

amended to include the above mitigation and submitted to the Agency within 90 days after

issuance of this IRED.

• For propetamphos, tolerances for residues in food commodities will remain in effect and

unchanged until a full reassessment of the cumulative risk assessment for all OP pesticides is

completed. Upon completion of the cumulative risk assessment, EPA will issue its final

tolerance reassessment decision for propetamphos and may request further risk mitigation

measures. For all OPs, raising and/or establishing tolerances will be considered once a

cumulative assessment is completed.