Development of REACH Generic Exposure Scenarios for Substances Used as Coformulants in Plant Protection Products

Integr Envir Assess & Manag

Bonifay²,

Krass

et al. 2020

Self Cite

The European Registration, Evaluation, Authorisation and Restriction of Chemicals (REACH) regulation requires that quantitative environmental risk assessment is carried out for hazardous substances used as coformulants in plant protection products (PPPs), if registered above 10 t/y. The European Crop Protection Association (ECPA) has developed generic exposure scenarios and specific environmental release categories (SpERCs) to support these risk assessments. The SpERCs offer refinements to the default release factors defined in environmental release categories (ERCs) and are intended to be used with nested multimedia mass balance models as part of the assessment of regional predicted environmental concentrations. Based on the application method of PPPs, 2 scenarios were defined for which SpERCs were developed: 1) spraying of PPPs and 2) direct application of granular products or treated seeds to soil. The SpERC for spray applications includes release factors to air and soil that depend on the vapor pressure of the coformulant. Calculations are presented to support the subSpERCs describing the transition from nonvolatile to volatile behavior. The most recent version of the spray application SpERC defines a release factor for surface water and more conservative release factors to soil compared with previous versions. Use of the ECPA SpERCs allows the coformulant emissions from PPPs to be fully accounted for in the regional‐scale environmental risk assessment for a given substance, along with all other sources of emissions. Qualitative and quantitative justification for the ECPA‐derived SpERCs is presented and serves as the background documentation to the online European Chemicals Agency (ECHA) SpERC factsheets. The approach developed here whereby regional‐scale SpERCs are used in combination with a customized local‐scale exposure model is potentially applicable for other sectors that are required to conduct exposure assessments outside the scope of the standard environmental REACH models. Integr Environ Assess Manag 2020;16:472–480. © 2020 Syngenta Crop Protection AG. Integrated Environmental Assessment and Management published by Wiley Periodicals, Inc. on behalf of Society of Environmental Toxicology & Chemistry (SETAC)

Section: Methodsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

REACH Specific Environmental Release Categories for Plant Protection Product Applications

Integr Envir Assess & Manag

Bonifay²,

Krass

et al. 2020

Self Cite

“…These activities have been translated into REACH use descriptors (ECHA, 2010), and standardized in GES for professional workers (farmers) and consumers (‘amateurs’) in Table 1. The rationale behind the use mapping, use descriptor assignment, and GES development has been described elsewhere (Dobe et al ., 2017). OWB was explicitly developed to provide the conservative dermal and inhalation exposure estimates required for each contributing scenario listed in Table 1.…”

Section: Methodsmentioning

confidence: 99%

“…Dobe et al . (2017) describe the practical considerations made in creating additional specific contributing scenarios versus broadening the applicability domain of an exposure model, by taking into account additional tasks.…”

Section: Methodsmentioning

confidence: 99%

“…The European Crop Protection Association (ECPA) has developed standardized generic exposure scenarios (GES), which enable manufacturers and downstream users of substances used as co-formulants in plant protection products (PPP) to readily assess their use in an efficient manner (Dobe et al ., 2017). To minimize the number of GES and support efficient supply chain communication, a worker exposure model with a suitably broad applicability domain was required to provide conservative exposure predictions for these GES.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

REACH Worker Exposure Model for Co-formulants Used in Plant Protection Products

Mostert¹,

Bonifay²,

Annals of Work Exposures and Health

et al. 2018

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BackgroundSubstances used as co-formulants in plant protection products (PPP) may require registration under Regulation (EC) No. 1907/2006 (REACH), and additionally where an exposure assessment is required, this must take into consideration the specifics of the PPP use.ObjectivesThis work reports a customized screening level model developed to support human health risk assessment of operators, workers, and bystanders (OWB) for co-formulants used in PPP. The OWB model was designed to closely integrate with REACH generic exposure scenarios (GES) for PPP developed by the European Crop Protection Association (ECPA). The use of these tools in combination is expected to lead to a more standardized and hence efficient risk assessment of co-formulants. This study describes the basis for OWB exposure predictions as well as benchmarking against relevant REACH exposure models for equivalent tasks. The benchmarking was carried out to gain some insight into the initial assumption that the most commonly used tier 1 REACH model would be more conservative than the specific PPP models used for regulatory risk assessments under PPP legislation.MethodExisting exposure models with regulatory acceptance for the most common types of PPP and their professional and consumer uses were selected. The German BBA model was used to assess spray applications. Granule and seed dispersal was assessed using the US Environmental Protection Agency (EPA) Pesticide Handlers Exposure Database (PHED). ECETOC TRA was employed to assess exposure during certain tasks performed in seed treatment, not covered by these PPP models. Where the underlying models featured multiple exposure determinants, the exposure was calculated for all permutations, and the worst-case exposure selected and reported for use in risk assessment. The PPP models are based on measured data collected during actual application of PPP; hence, the worst-case exposure predicted was expected to reflect a realistic worst case for these tasks.ResultsOWB was implemented as an Excel spreadsheet. Exposure models, parameters, and exposure and risk estimates are reported in a REACH-compliant output format to facilitate the registration of co-formulant uses. As would be expected, benchmarking OWB against the PPP-specific exposure models demonstrated equivalence with the worst-case prediction from these underlying PPP models. For the scenarios modelled, the tier 1 ECETOC TRA gave more conservative predictions than OWB. The reduction in conservatism is attributed to the underlying PPP models being based on measured data collected specifically during the use of PPP, compared to the data underlying ECETOC TRA, based mainly on industrial workplace uses.ConclusionsOWB provides inhalation and dermal exposure estimates for co-formulants used in PPP which are equivalent to the worst-case estimates from existing specialized PPP exposure models based on measured data. OWB has simplified information requirements in comparison to higher-tier REACH or PPP models. Use of OWB in combination with the defin...

Environmental exposure assessment of co‐formulants in plant protection products under REACH

McMillan¹,

Bonifay²,

Integr Envir Assess & Manag

et al. 2023

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It is a regulatory requirement to assess co‐formulants in plant protection products (PPP) under the European Registration, Evaluation, Authorisation and Restriction of Chemicals (REACH) legislation. The standard environmental exposure assessment framework for chemicals under REACH is a multicompartmental mass‐balanced model and, at the local scale, is designed for use with urban (wide dispersive) or industrial (point source) emissions. However, the environmental release of co‐formulants used in PPP is to agricultural soil and indirectly to waterbodies adjacent to a field and, for sprayed products, to the air. The Local Environment Tool (LET) has been developed to assess these specific emission pathways for co‐formulants in a local‐scale REACH exposure assessment, based on standard approaches and models used for PPP. As such, it closes a gap between the standard REACH exposure model's scope and REACH requirements to assess co‐formulants in PPP. When combined with the output of the standard REACH exposure model, the LET includes an estimate of the contribution from other nonagricultural background sources of the same substance. The LET is an improvement over the use of higher tier PPP models for screening purposes because it provides a simple standardized exposure scenario. A set of predefined and conservatively selected inputs allows a REACH registrant to conduct an assessment without requiring detailed knowledge of PPP risk assessment methods or typical conditions of use. The benefit to the co‐formulant downstream user (formulators) is a standardized and consistent approach to co‐formulant assessment, with meaningful and readily interpretable conditions of use. The LET can serve as an example to other sectors of how to address possible gaps in the environmental exposure assessment by combining a customized local‐scale exposure model with the standard REACH models. A detailed conceptual explanation of the LET model is provided here together with a discussion on its use in a regulatory context. Integr Environ Assess Manag 2023;00:1–11. © 2023 BASF SE, Bayer AG et al. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC)