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AbstractThe ubiquitous presence of more than 80,000 chemicals in thousands of consumer products used on a daily basis stresses the need for screening a broader set of chemicals than the traditional well‐studied suspect chemicals. This high‐throughput screening combines stochastic chemical‐product usage with mass balance‐based exposure models and toxicity data to prioritize risks associated with household products. We first characterize product usage using the stochastic SHEDS‐HT model and chemical content in common household products from the CPDat database, the chemical amounts applied daily varying over more than six orders of magnitude, from mg to kg. We then estimate multi‐pathways near‐ and far‐field exposures for 5,500 chemical‐product combinations, applying an extended USEtox model to calculate product intake fractions ranging from 0.001 to ∼1, and exposure doses varying over more than nine orders of magnitude. Combining exposure doses with chemical‐specific dose–responses and reference doses shows that risks can be substantial for multiple home maintenance products, such as paints or paint strippers, for some home‐applied pesticides, leave‐on personal care products, and cleaning products. Sixty percent of the chemical‐product combinations have hazard quotients exceeding 1, and 9% of the combinations have lifetime cancer risks exceeding 10−4. Population‐level impacts of household products ingredients can be substantial, representing 5 to 100 minutes of healthy life lost per day, with users' exposures up to 103 minutes per day. To address this issue, present mass balance‐based models are already able to provide exposure estimates for both users and populations. This screening study shows large variations of up to 10 orders of magnitude in impact across both chemicals and product combinations, demonstrating that prioritization based on hazard only is not acceptable, since it would neglect orders of magnitude variations in both product usage and exposure that need to be quantified. To address this, the USEtox suite of mass balance‐based models is already able to provide exposure estimates for thousands of product‐chemical combinations for both users and populations. The present study calls for more scrutiny of most impacting chemical‐product combinations, fully ensuring from a regulatory perspective consumer product safety for high‐end users and using protective measures for users.

Life Cycle Assessment (LCA) aims to compare environmental impacts of products and services on a functional basis. With life-cycle inventories established, LCA must provide in its Life Cycle Impact Assessment (LCIA) phase impact factors per kg of chemical emission/extracted resources, expressed in term of impacts on human health, ecosystem quality, or resources depletion. In this presentation, we track the development and evolution of LCIA methods over three decades and focus on the role of SETAC in collaboration with the United Nations Environment Program in forming the Life-Cycle Initiative to establish, interpret, and disseminate a globally harmonized LCIA approach. The Initiative has hosted a series of complementary efforts for LCIA consensus building, striving for recommendations and guidance on LCIA methods and factors. SETAC conferences and Pellston Workshops have provided important venues for the Initiative process. Three rounds of SETAC working groups have resulted in category-specific recommendations for developing LCIA impact indicators, taking advantage of broader consensus efforts, such as the World Health Organization, USEPA, and EU health risk assessment efforts. A combination of academic, government, and industry experts have participated in these efforts. As an informative example we will review the development and dissemination of the USEtox global scientific consensus model, which provides LCIA characterization factors for human toxicity and ecotoxicity, and which is now used worldwide. It is the default tool in both the European Union and North America. We conclude by considering future needs and opportunities for LCIA with a focus on the continuing role of SETAC.

Processing of the articles for this web presentation has been supported within the European Commission's 7th framework programme in the project ICT-ENSURE, Literature Information System. http://www.iai.fzk.de/Fachgruppe/GI/litArchive/EnviroInfo/2004Geneva/Volume1-Sh_ring_EnviroInfo_2004/How_to_assess_the_Environmental_State_of_EU_region--a1777.html ; International audience ; EPSILON project is aiming at assessing sustainability of all European regions to provide a quantitative tool for policy decision making. EPSILON will propose a coherent view of the economic, social, institutional and environmental state of a region, taking into account local as well as relationships indicators. EPSILON provides sustainability maps for monitoring & benchmarking of regions at different levels of aggregation of indicators thanks to a GIS integrated computerized model. This paper is focused on presenting EPFL modelling of the environmental dimension within the sustainability model. Its particularities are: The full use of the DPSIR 3 approach to define relevant environmental indicators at the State level. These indicators are structured across environmental themes (Air, Soil, Water and Land). The inclusion of proper environmental interactions across Europe by using results from transboundary fate models such as EMEP. The aggregation of environmental indicators according to scientific backgrounds. Whenever possible, this aggregation relies on the recognition of the relative impact of the pollutants on human health using the DALYs 4 parameters. These DALYs have been derived from the IMPACT2002 model, a multimedia fate and exposure model for the impact assessment of toxic chemicals covering all Western Europe (Pennington et al., 2003a).

Life cycle assessment (LCA) is a framework for comparing products according to their total estimated environmental impact, summed over all chemical emissions and activities associated with a product at all stages in its life cycle (from raw material acquisition, manufacturing, use, to final disposal). For each chemical involved, the exposure associated with the mass released into the environment, integrated over time and space, is multiplied by a toxicological measure to estimate the likelihood of effects and their potential consequences. In this article, we explore the use of quantitative methods drawn from conventional single‐chemical regulatory risk assessments to create a procedure for the estimation of the cancer effect measure in the impact phase of LCA. The approach is based on the maximum likelihood estimate of the effect dose inducing a 10% response over background, ED10, and default linear low‐dose extrapolation using the slope βED10 (0.1/ED10). The calculated effects may correspond to residual risks below current regulatory compliance requirements that occur over multiple generations and at multiple locations; but at the very least they represent a "using up" of some portion of the human population's ability to accommodate emissions. Preliminary comparisons are performed with existing measures, such as the U.S. Environmental Protection Agency's (U.S. EPA's) slope factor measure q1*. By analyzing bioassay data for 44 chemicals drawn from the EPA's Integrated Risk Information System (IRIS) database, we explore estimating ED10 from more readily available information such as the median tumor dose rate TD50 and the median single lethal dose LD50. Based on the TD50, we then estimate the ED10 for more than 600 chemicals. Differences in potential consequences, or severity, are addressed by combining βED10 with the measure disability adjusted life years per affected person, DALYp. Most of the variation among chemicals for cancer effects is found to be due to differences in the slope factors (βED10) ranging from 10−4 up to 104 (risk of cancer/mg/kg‐day).

We employ the intake fraction (iF) as an effective tool for expressing the source‐to‐intake relationship for pollutant emissions in life cycle analysis (LCA) or comparative risk assessment. Intake fraction is the fraction of chemical mass emitted into the environment that eventually passes into a member of the population through inhalation, ingestion, or dermal exposure. To date, this concept has been primarily applied to pollutants whose primary route of exposure is inhalation. Here we extend the use of iF to multimedia pollutants with multiple exposure pathways. We use a level III multimedia model to calculate iF for TCDD and compare the result to one calculated from measured levels of dioxin toxic equivalents in the environment. We calculate iF for emissions to air and surface water for 308 chemicals. We correlate the primary exposure route with the magnitudes of the octanol‐water partition coefficient, Kow, and of the air‐water partitioning coefficient (dimensionless Henry constant), Kaw. This results in value ranges of Kow and Kaw where the chemical exposure route can be classified with limited input data requirements as primarily inhalation, primarily ingestion, or multipathway. For the inhalation and ingestion dominant pollutants, we also define empirical relationships based on chemical properties for quantifying the intake fraction. The empirical relationships facilitate rapid evaluation of many chemicals in terms of the intake. By defining a theoretical upper limit for iF in a multimedia environment we find that iF calculations provide insight into the multimedia model algorithms and help identify unusual patterns of exposure and questionable exposure model results.

In Part 1 of this article we developed an approach for the calculation of cancer effect measures for life cycle assessment (LCA). In this article, we propose and evaluate the method for the screening of noncancer toxicological health effects. This approach draws on the noncancer health risk assessment concept of benchmark dose, while noting important differences with regulatory applications in the objectives of an LCA study. We adopt the central tendency estimate of the toxicological effect dose inducing a 10% response over background, ED10, to provide a consistent point of departure for default linear low‐dose response estimates (βED10). This explicit estimation of low‐dose risks, while necessary in LCA, is in marked contrast to many traditional procedures for noncancer assessments. For pragmatic reasons, mechanistic thresholds and nonlinear low‐dose response curves were not implemented in the presented framework. In essence, for the comparative needs of LCA, we propose that one initially screens alternative activities or products on the degree to which the associated chemical emissions erode their margins of exposure, which may or may not be manifested as increases in disease incidence. We illustrate the method here by deriving the βED10) slope factors from bioassay data for 12 chemicals and outline some of the possibilities for extrapolation from other more readily available measures, such as the no observable adverse effect levels (NOAEL), avoiding uncertainty factors that lead to inconsistent degrees of conservatism from chemical to chemical. These extrapolations facilitated the initial calculation of slope factors for an additional 403 compounds; ranging from 10−6 to 103 (risk per mg/kg‐day dose). The potential consequences of the effects are taken into account in a preliminary approach by combining the βED10) with the severity measure disability adjusted life years (DALY), providing a screening‐level estimate of the potential consequences associated with exposures, integrated over time and space, to a given mass of chemical released into the environment for use in LCA.

Most alternatives assessments (AA) published to date are largely hazard-based rankings, and as such may not represent a fully informed consideration of the advantages and disadvantages of possible alternatives. With an assessment goal of identifying an alternative chemical that is more sustainable, other attributes beyond hazard are also important, including exposure, risk, life-cycle impacts, performance, cost, and social responsibility. Building on the 2014 recommendations by the U.S. National Academy of Sciences to improve AA decisions by including comparative exposure assessment, the HESI Sustainable Chemical Alternatives Technical Committee, which consists of scientists from academia, industry, government, and NGOs, has developed a qualitative comparative exposure approach. Conducting such a comparison can screen for alternatives that are expected to have a higher human or environmental exposure potential, which could trigger a higher-tiered, more quantitative exposure assessment on the alternatives being considered, minimizing the likelihood of regrettable substitution. This talk will demonstrate an approach for including chemical- and product-related exposure information in a qualitative AA comparison. Starting from existing hazard AAs, a series of three chemical-product application scenarios were examined to test the concept, to understand the effort required, and to determine the value of exposure data in AA decision- making. The group has developed a classification approach for ingredient and product parameters to support comparisons between alternatives as well as 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, while the product parameters include aspects such as exposure pathways, use pattern, frequency/duration of use, chemical concentration in product, and use volume, accessibility, and disposal.Key learnings, challenges, and opportunities for further work will also be presented. The views expressed in this presentation do not necessarily reflect the views or policies of the U.S. Environmental Protection Agency.

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.