Standard Operating Procedures for Residential Pesticide Exposure Assessment
The Standard Operating Procedures for Residential Pesticide Exposure Assessment (Residential SOPs) are instructions for estimating exposure resulting from the most common non-occupational pesticide uses including lawn and garden care, foggers, and pet treatments. They are an important tool for the Pesticide Program because they provide:
- guidance for exposure assessors who are responsible for the residential non-dietary component of the risk assessment process;
- a description of the methods used to evaluate pesticide chemicals in a straightforward and user-friendly fashion; and
- a framework for future research directed at improvements in the residential assessment process for pesticides.
The current version of the Residential SOPs (referred to as the 2012 Residential SOPs) can be downloaded below.
- Residential SOPs (entire document)-Revised October 2012
The residential SOP document provides background, data analysis, and assessment characterization. Based on that, the following spreadsheets can be used to perform the calculations. Users should be familiar with the SOP document prior to use of the spreadsheets. These versions are interim and will be updated following feedback from users.
- Residential Handler (all SOPs) (xlsx)(1 pg, 79 K)
- Lawns/Turf SOP (xlsx)(1 pg, 68 K)
- Gardens and Trees SOP (xlsx)(1 pg, 39 K)
- Outdoor Fogging/Misting Systems SOP (xlsx)(1 pg, 53 K)
- Insect Repellents SOP (xlsx)(1 pg, 32 K)
- Indoor Environments SOP (xlsx)(1 pg, 97 K)
- Treated Pets SOP (xlsx)(1 pg, 29 K)
- Impregnated Materials SOP (xlsx)(1 pg, 41 K)
- Treated Paints & Preservatives SOP (xlsx)(1 pg, 30 K)
Incorporation of the 2012 Residential SOPs Into the Evaluation of New Pesticide Registrations and Registration Review
Many of the Agency’s existing pesticide registration decisions relied on previous versions of the Residential SOPs to assess residential pesticide exposures. As the Agency evaluates new pesticide registration actions and conducts Registration Review, the 2012 Residential SOPs will be used to evaluate residential exposures.
One of the advantages of the 2012 Residential SOPs is the inclusion of data analyses that have been performed with more complete or appropriate statistical procedures, including, when sufficient data were available, distributional analysis to evaluate a more complete range of potential exposure. Currently, the Agency plans to continue to use point-estimates deterministically in our standard exposure assessments which evaluate short-term (up to 30 days), intermediate-term (up to 6 months), and long-term (greater than 6 months) durations as well as lifetime exposures for potentially carcinogenic chemicals. For these exposure assessments, the Agency believes arithmetic means are appropriate. However, with the additional capability to examine “high-end” exposures, the Agency plans to develop guidance on assessing acute residential exposure and risk, in coordination with staff toxicologists. Once developed, we will update the Residential SOPs to include appropriate values for such assessments.
The Residential SOPs use the most reliable scientific data available. Some of this data is proprietary and subject to the protections established in the Federal Insecticide Fungicide and Rodenticide Act (FIFRA). Companies who rely on such data to support a registration of a pesticide product will be required to comply with the data protection provisions of FIFRA and the Agency’s regulations. Pesticide registrants may opt to conduct and submit their own studies for the purpose of supporting product registration.
For various stakeholders, it is important to consider the potential impacts on exposure estimates as the Agency begins to transition from the 1997 SOPs to the 2012 SOPs. In some cases, the 2012 Residential SOPs result in higher exposure estimates and in other cases they result in lower exposure estimates when compared with the 1997 SOPs. These impacts are ultimately the effect of using more scientifically reliable methodologies and data. Despite the differences in exposure estimates for some scenarios, the Agency believes that the 2012 Residential SOPs, which utilize more current and more extensive scientifically reliable data and exposure assessment methodologies, result in health protective exposure estimates and are an improvement of the 1997 SOPs.
Some examples of scenario changes are discussed below. (For more details, a full explanation of each scenario is available in the 2012 Residential SOP document).
- The turf SOP results in higher dermal exposure estimates and lower incidental oral (i.e., hand-to-mouth) exposure estimates. The higher dermal exposure estimates are the result of post-application exposure data that better reflect actual activities. The lower hand-to-mouth exposure estimates are due to a new algorithm that was modified from the EPA’s Stochastic Human Exposure and Dose Simulation (SHEDs) Model, which better reflects the activities involved in the non-dietary ingestion scenarios (e.g., loading of residues on hands and removal processes).
- The indoor environments SOP results in lower dermal and incidental oral exposure estimates using the 2012 SOPs compared to the 1997 SOPs. The lower dermal exposure estimates result from refinements of exposure methods to account for differences between the types of indoor application (e.g., broadcast versus crack and crevice) and also newer available indoor exposure data which better reflect the transfer of residues from indoor surfaces. The lower hand-to-mouth exposure estimates are due to the use of the modified SHEDs algorithm, as explained above.
- The pet SOP results in lower dermal and incidental oral exposure estimates using the 2012 SOPs compared with the 1997 SOPs. The lower dermal exposure estimates are due to incorporation of new post-application petting studies which more accurately represent the pesticide residues available for transfer from treated fur. The lower incidental oral exposure estimates are due to the use of the modified SHEDs algorithm as explained above.
Developed by the Health Effects Division of EPA’s Office of Pesticide Programs in the 1990s, pursuant to the Food Quality Protection Act (FQPA) requiring consideration of non-dietary non-occupational exposures for the purposes of aggregate pesticide exposure estimates, the Residential SOPs were first presented to the FIFRA Science Advisory Panel (SAP) in 1997 with additional FIFRA SAP review in 1999. They have since been used with various updates to data sources and methodologies, including a supplemental document in 2001. See Overview of Issues Related to the Standard Operating Procedures for Residential Exposure Assessment.
The 2012 Residential SOPs represents a substantial revision to those used since the 1990s. This revision:
- Evaluates and incorporates interim updates and revisions since 1997;
- Reflects a comprehensive search and analysis of more current and reliable exposure data for the purposes of informing standard algorithm inputs; and
- Updates or revises standard exposure assessment methods.
The Agency presented a draft version of the 2012 Residential SOPs to the FIFRA SAP in 2009. The charge to the Panel was to ensure that additional data were identified, additional exposure sources were formally incorporated, and the use of updated information was accomplished in a scientifically credible manner. Following the 2009 review, the Agency incorporated comments from the SAP and other stakeholders including the California Department of Pesticide Regulation and Canada’s Pest Management Regulatory Authority. Additionally, for applicable exposure factors, the Agency incorporated the recently revised Exposure Factors Handbook: 2011 Edition.
The Agency views the Residential SOPs as a “living document” subject to revision based on new or more contemporary data or other information. As such, the Agency plans on conducting its own periodic reviews of the SOPs to consider any new information and, if appropriate, revise the document to reflect its incorporation.
To provide feedback or request additional information, please email the Residential SOP team.