A quantitative screening-level approach to incorporate chemical exposure and risk into alternative assessment evaluations

Integrated environmental health assessment: Proposed approaches to exposure during chemical incidents

An integrated environmental health exposure assessment (IEHA) refers to the integration of human biomonitoring data (HBM) and environmental measurements and aims to optimize the exposure assessment process. Due to lack of data, this approach remains an issue during chemical incidents. This study aims to explore integrated exposure approaches for assessing human health risks during chemical incidents. Based on the Preferred Reporting Items of Systematic reviews and Meta-Analyses statement, a literature analysis was performed. A level of confidence ranging from 1 to 4 was established to define the quality and strength of data used to undertake an IEHA approach. Twenty-seven articles (n = 18) and texts (n = 9) from Europe (41%) and the United States (37%) were analyzed. Among the 18 scientific articles, 61% (n = 11) presented a quantitative approach and 17% (n = 3) presented a qualitative approach. Quantitative approaches must be based on accurate data, coupled with predictive models. Of all the scientific papers, 40% (n = 7) responded to a confidence level greater than or equal to 2. Uncertainties detected through the integrated exposure approaches were related to input data, analytical methods, and HBM reference value interpretations. During chemical incidents, direct measurements were the most relevant data. Few scientific studies have developed an integrated approach during emergency situations. However, when this was used, they presented a high level of confidence by defining levels of exposure that support decision-making processes. Despite the multiple approaches, there was a lack of guidelines allowing an integrated risk assessment to be performed during an emergency chemical exposure. Integr Environ Assess Manag 2024;20:481-497. © 2023 SETAC.

Informed substitution of hazardous chemicals through the lens of California's Safer Consumer Products Alternatives Analysis: Best practices, challenges, and opportunities

California adopted the Safer Consumer Products (SCP) regulations in 2013, which mandate that companies that manufacture specific products containing designated chemicals of concern complete an Alternatives Analysis. Alternatives Analysis is a process to avoid regrettable substitution by identifying, comparing, and selecting safer alternatives based on technical functions, hazards, exposure pathways, life-cycle multimedia impacts, and economic impacts. The SCP Alternatives Analysis builds upon and expands existing frameworks for alternatives assessments (AAs). The aim of this study was to identify practices from AA that facilitate the robust assessment of alternatives and that align with SCP requirements and identify gaps in the practice. We evaluated completed AAs for methods regarding transparency and careful documentation of information sources, data gaps, uncertainty, criteria, and justification for decision-making. The AAs in this review demonstrate some of the challenges in the field. Most AAs have a constrained scope and only consider chemical substitutes rather than a broad array of functional alternatives. Their scopes were also limited in the hazard endpoints that were evaluated. This was most noted with ecotoxicity endpoints, which were generally confined to aquatic toxicity. The majority of AAs do not explicitly explain their decision-making methods or adequately discuss tradeoffs across the adverse impacts. The AAs also lack the analysis in the exposure, life-cycle impacts, and economic impacts that are required in the SCP Alternatives Analysis process. Further, we recommend strategies and research opportunities to address these challenges and strengthen the practice of AAs. Integr Environ Assess Manag 2022;18:1007-1019. © 2021 SETAC.

Phthalate Plasticizers in Children's Products and Estimation of Exposure: Importance of Migration Rate

Plasticizers are added to diverse consumer products including children's products. Owing to their potential for endocrine disruption, the use of phthalate plasticizers is restricted in many children's products. In this study, exposure to five phthalate esters (dibutylphthalate, di(2-ethylhexyl) phthalate (DEHP), diethyl phthalate, di-isobutyl phthalate, and diisononyl phthalate (DINP)) and an alternative (di-ethylhexyl adipate) was assessed by the use of children's products based on chemical analysis of 3345 products purchased during 2017 and 2019 in Korea. Plasticizers were found above the detection limits in 387 products, and DEHP and DINP were the two most predominantly detected plasticizers. Deterministic and probabilistic estimation of the margin of exposure at a screening level revealed that the use of children's products might be an important risk factor. However, it is also highly likely that the exposure could be overestimated, because the migration rate was estimated based solely on the content of plasticizers in children's products. Chemical migration is a key process determining the absorption of plasticizers from products; thus, further refinements in experimental determination or model estimation of the migration rate are required.

Qualitative approach to comparative exposure in alternatives assessment

Most alternatives assessments (AAs) published to date are largely hazard-based rankings, thereby ignoring potential differences in human and/or ecosystem exposures; as such, they may not represent a fully informed consideration of the advantages and disadvantages of possible alternatives. Building on the 2014 US National Academy of Sciences recommendations to improve AA decisions by including comparative exposure assessment into AAs, the Health and Environmental Sciences Institute's (HESI) Sustainable Chemical Alternatives Technical Committee, which comprises scientists from academia, industry, government, and nonprofit organizations, developed a qualitative comparative exposure approach. Conducting such a comparison can screen for alternatives that are expected to have a higher or different routes of human or environmental exposure potential, which together with consideration of the hazard assessment, could trigger a higher tiered, more quantitative exposure assessment on the alternatives being considered, minimizing the likelihood of regrettable substitution. This article outlines an approach for including chemical ingredient- and product-related exposure information in a qualitative comparison, including ingredient and product-related parameters. A classification approach was developed for ingredient and product parameters to support comparisons between alternatives as well as a methodology to address exposure parameter relevance and data quality. The ingredient parameters include a range of physicochemical properties that can impact routes and magnitude of exposure, whereas the product parameters include aspects such as product-specific exposure pathways, use information, accessibility, and disposal. Two case studies are used to demonstrate the application of the methodology. Key learnings and future research needs are summarized. Integr Environ Assess Manag 2018;00:000-000. © 2018 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals, Inc. on behalf of Society of Environmental Toxicology & Chemistry (SETAC).

Combining in Silico Tools with Multicriteria Analysis for Alternatives Assessment of Hazardous Chemicals: A Case Study of Decabromodiphenyl Ether Alternatives

Alternatives assessment is applied for minimizing the risk of unintentionally replacing a hazardous chemical with another hazardous chemical. Central challenges are the diversity of properties to consider and the lack of high-quality experimental data. To address this, a novel alternatives assessment procedure was developed based on in silico data and multicriteria decision analysis (MCDA) methods. As a case study, 16 alternatives to the flame retardant decabromodiphenyl ether were considered. The hazard properties included persistence (P), bioaccumulation potential (B), toxicities (T), and mobility in water (M). Databases were consulted and 2866 experimental data points were collected for the target chemicals; however, these were mostly replicate data points for some hazard criteria for a subset of alternatives. Therefore, in silico data and three MCDA strategies were tested including heat mapping, multiattribute utility theory (MAUT), and Elimination Et Choix Traduisant la REalité (ELECTRE III). The heat map clearly showed that none of the target chemicals are hazard-free, whereas MAUT and ELECTRE III agreed on ranking the "least worst" choices. This study identified several challenges and the complexity in the alternatives assessment processes motivating more case studies combining in silico and MCDA approaches.

Impact of European chemicals regulation on the industrial use of plasticizers and patterns of substitution in Scandinavia

REACH aims at promoting the safe use of chemicals in Europe, inter alia by identification and regulation of substances of very high concern (SVHCs). Once identified, SVHCs need to be substituted by safer alternatives. However, substitutes are frequently not safer than the substances that they replace but rather show similar hazard profiles, resulting in regrettable substitution. This paper investigates the impact of chemicals regulation on substitution of chemicals by analyzing time trends in the industrial use of chemicals from 2000 to 2014 in Scandinavia. It is shown that the use of ten water-relevant SVHCs decreased by about 90% in the considered period in Sweden as compared to a control group of unregulated substances which decreased by only 20%. A closer inspection of the use of 23 highly used plasticizers revealed that the use of regulated phthalate plasticizers decreased while the use of non-phthalate plasticizers increased. A first comparison of hazardous properties showed that during the 15-years period chemical substitution drastically reduced the chemical hazard burden of plasticizers in Scandinavia for both, the environment and human health. This study shows that regulation and the related discussion on chemicals safety have significantly reduced the chemical hazard burden from plasticizers in Scandinavia since the year 2000. It is assumed that similar trends can be found for the whole European Union. To combat regrettable substitution, mitigation options are suggested, including information-based tools for the identification of safer alternatives and an improved accessibility of information on production volumes and uses of chemicals to allow for an improved assessment of chemical's risk.