Qualitative Approach to Comparative Exposure in Alternatives Assessment

Abstract

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).

Advancing Alternatives Assessment for Safer Chemical Substitution: A Research and Practice Agenda

“…Of particular interest is the development of methods for evaluating and comparing chemicals that may not meet criteria for persistent, bioaccumulative, and toxic substances but are continuously used and released into the environment in such large quantities that exposure to humans and ecosystems is constant (for example, some phthalates). Recent articles by Fantke et al (2016), Mason et al (2018), and the Health and Environmental Sciences Institute (Greggs et al 2019, in this issue) represent efforts to develop approaches for integrating exposure considerations into the AA process that could serve as points of departure for future guidance developed by government, scientific, or professional bodies.…”

Life cycle based alternatives assessment (LCAA) for chemical substitution

“…We multiply the chemical amount in the given product by the product intake fraction (PiF) to yield consumer exposure doses via all relevant exposure pathways. 8,23,24 Heat maps displaying exposure doses as a function of the product category-specific factors driving variability in exposure, can be used to identify a suitable space 46 CF j = GWP 100,j × EF j,e a Focus on those life cycle stages that differ between the product containing the harmful chemical versus the same product containing an alternative. b Focus on those impact categories that are relevant for the given chemical: if bioactive (e.g.…”

“…However, current frameworks suffer from inconsistencies in data and models applied, from relying on qualitative or semi-quantitative indicators, and from the lack of effectively and efficiently addressing exposure and life cycle impacts. 4,[6][7][8][9][10] More specifically, quantifying exposure to chemicals in consumer products, and evaluating life cycle impacts associated with for example climate change, human and ecosystem toxicity, and water resources use, are commonly considered too complex and time-consuming. 11,12 History shows that ignoring the quantification of the various exposures and life cycle impacts may leave important trade-offs and problem-shifting unaddressed and can thus lead to regrettable substitutions.…”

Building a European exposure science strategy

“…Compared with toxicology, however, exposure science is still ill developed as an independent discipline [2,4]. Yet, it has become an indispensable element in various science and policy frameworks, from policy analysis to sustainability assessment [5][6][7][8][9][10][11][12][13], and has been proposed as an important component in chemical substitution [14,15]. Although many regulations and studies focus on exposure to chemicals, assessing and managing exposure to other stressors is increasingly acknowledged.…”