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AHETF Scenario Design and Field Study Protocol for Mixing and Loading of Pesticide Products in Water-Soluble Packaging. Jeff Evans Kelly Sherman Office of Pesticide Programs. 1. AHETF Status Recap. June 2008: HSRB reviewed the closed-cab airblast scenario
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AHETF Scenario Design and Field Study Protocol for Mixing and Loading of Pesticide Products in Water-Soluble Packaging Jeff Evans Kelly Sherman Office of Pesticide Programs 1
AHETF Status Recap June 2008: HSRB reviewed the closed-cab airblast scenario Fall 2008: AHETF conducted 2 closed-cab airblast field studies October 2008: HSRB reviewed the remaining field study protocols for the closed-cab airblast scenario HSRB reviewed the scenario design document and field study protocols for the open-cab airblast scenario Summer 2009: AHETF plans to conduct several closed-cab and open-cab airblast field studies 2
What’s Familiar about this Proposal? • No change to AHETF Governing Document or most SOPs • Design objectives, sample size and rationale, and cluster configuration are all similar to other AHETF scenarios reviewed • Protocol procedures related to ethical conduct are similar, but all issues raised by EPA and HSRB have all been addressed
What’s Different about this Proposal? • Monitors Mixer-Loaders; crop is unimportant • Scenario covers mixing dry pesticides in water-soluble packets (WSPs) with water, and loading the solution into various types of equipment for application as liquid sprays • Liquid sprays may be applied to virtually all types of crops, using a wide range of application equipment, in all areas of the U.S. • New Format for AHETF – a single protocol covers all five proposed field study sites • 12 new or updated SOPs • One new surrogate – acephate
AHETF Scenario Design and Field Study Protocol for Mixing and Loading of Pesticide Products in Water-Soluble Packaging:Science AssessmentJeff EvansHealth Effects Division 5
Scenario Definition • Mixing/Loading soluble or wettable powder pesticides enclosed in water-soluble packets (WSP) • Scenario supports assessing WSP mixing/loading for many crops under 3 sub-scenarios: • Mixing of WSPs directly into the tank used for the pesticide application • Mixing of WSPs into a "pre-mix" tank at the same concentration to be applied to the crop • Mixing of WSPs into a tank as a concentrated solution/suspension that must be further diluted and transferred to the final application tank
EPA Position on Scenario Definition • We agree with the AHETF plan to informally diversify these general equipment types • Each of the three sub-scenarios must be monitored at least once within each cluster • Diversity will be achieved—randomly or purposively—by assigning mixer/loaders to Amount-active-ingredient-Handled (AaiH) strata within each cluster • The proposal for 25 subjects in 5 clusters of 5 subjects each is appropriate for this scenario
Regulatory Requirements for PPE • Minimum Personal Protective Equipment (PPE) permitted by the Worker Protection Standard for acephate and carbaryl when engineering controls are used is chemical-resistant gloves • Other attire includes: long sleeved shirt, long pants, shoes, socks • In case of emergency (e.g., bag rupture) other PPE: coveralls, chemical-resistant footwear, and respirators must be available
Water-Soluble Packets Packets containing dry flowable product
Packets may also be placed into a variety of holding tanks, either fully diluted for use or as a concentrated solution for later further dilution and transfer to a spray tank
Lynn County, OR Russ Glover To accompany a variety of application scenarios
Proposed Surrogate Pesticides • EPA accepts the AHETF’s selection of acephate and carbaryl as surrogates • They are widely used and available in water soluble packets • They are used on a wide range of crops on farms of many sizes and types such that all AaiH strata can likely be filled in each cluster • They have reliable analytical methods, have been successfully used as surrogates in other AHETF studies, and are known to have the required stability under field study conditions
Proposed AaiH Strata • All exposure durations will be at least 4 hours • Each subject will mix/load at least 3 tanks of spray mixture • Five strata of AaiH in each cluster: • 5 to 17 pounds ai handled • 18 to 55 pounds ai handled • 56 to 182 pounds ai handled • 183 to 603 pounds ai handled • 604 to 2,000 pounds ai handled (limit use of acephate to 700 pound AaiH)
Conclusions of Science Assessment • The Field and Laboratory QA/QC aspects are robust • The Scenario is well defined • This protocol has addressed the technical aspects of applicable exposure monitoring guidelines • Draft - EPA Series 875 Group A - Applicator Monitoring Test Guidelines • OECD Applicator Guidelines • Good Laboratory Practices (GLPs) (40CFR Part 160) • Limit AaiH of acephate to 700 pounds
AHETF Scenario Design and Field Study Protocol for Mixing and Loading of Pesticide Products in Water-Soluble Packaging:Ethics Assessment Kelly Sherman Human Research Ethics Reviewer Office of Pesticide Programs 22
Value to Society • Exposure data for workers who mix and load pesticides contained in water-soluble packets are needed to support EPA risk assessments • Studies conducted under this protocol will constitute the entire exposure data set for this scenario in the Agricultural Handler Exposure Database (AHED®) • Knowledge likely to be gained will be used to estimate dermal and inhalation exposure from use of a wide range of agricultural pesticides available in water-soluble packets 23
Recruiting and Consent • Equitable subject selection • Fully informed choice • Fully voluntary choice • Respect for subjects 24
Risks, Benefits, and Risk-Benefit Balance • Risks have been fully identified and effectively minimized • Residual risks to subjects will be low • Risks to subjects are reasonable in light of potential societal benefits 25
Independent Ethics Review • The Independent Investigational Review Board (IIRB) of Plantation FL: • Reviewed and approved the protocol and informed consent materials • Is independent of the sponsors and investigators • Is registered with OHRP • Is seeking accreditation from AAHRPP • IIRB’s “Human Research Protection Program Plan” was included among the LNX-002 materials 26
EPA Review • No deficiencies relative to 40 CFR 26, subparts K and L, or to FIFRA 12(a)(2)(P) • All issues identified in previous EPA and HSRB reviews have been satisfactorily addressed • 21/24 issues addressed in the Scenario Design and Field Study Protocol (dated 1/16/09) • 3 remaining issues addressed in the AHETF’s Response to EPA’s Science and Ethics Review (dated 5/12/09) 27
Representativeness • Concern: Are study participants representative of the target population of growers and commercial applicators? • Past AHETF efforts to address concern were unsuccessful • New AHETF Proposal: • Characterize eligible growers – both those willing and unwilling to participate • Ask experts with local knowledge to assess characteristics of willing and unwilling growers in terms of representativeness • EPA View: AHETF proposal is effective and ethically acceptable
Presentation of Individual Exposure Data • Concern: Workers who learn that their exposure is lower than average might become complacent or adopt riskier behavior • AHETF proposal: • Letter conveying the importance of diligence in the handling of pesticides, regardless of the worker’s individual exposure levels • Graphics depicting exposure distribution across body parts for the individual worker and the group average • EPA brochure describing safe practices for pesticide handlers • EPA View: AHETF proposal is effective and ethically acceptable
Localization of Spanish Translations • Concern: Spanish translations should reflect specific terminology and wording common to the study locale • AHETF proposal: • Modify documents as appropriate to meet local needs • Contact people in different regions of the country who provide pesticide safety training to Spanish-speaking agricultural workers • Ask reviewers to suggests changes in wording that would improve understanding in their geographic area • Ask reviewers to suggest translations for certain agricultural terms • EPA View: AHETF proposal is effective and ethically acceptable
Applicable Ethical Standards Proposal for third-party research involving intentional exposure of human subjects to a pesticide, with the intention of submitting the resulting data to EPA under the pesticide laws The primary ethical standards applicable to the conduct of this research are 40 CFR 26, Subparts K and L 31
Conclusions of Ethics Assessment • Protocol meets the applicable requirements of 40 CFR part 26, subparts K and L
Charge Questions If proposed field study protocol AHE120 is revised as suggested in EPA’s reviews and if the research is performed as described: 1. Is the research likely to generate scientifically reliable data, useful for assessing the exposure of handlers who mix and load soluble or wettable powder pesticides in water-soluble packaging? 2. Is the research likely to meet the applicable requirements of 40 CFR part 26, subparts K and L? 33