By Lynn L. Bergeson and Carla N. Hutton
The U.S. Environmental Protection Agency (EPA) is launching a webinar series in collaboration with the PETA Science Consortium International (PSCI), Institute for In Vitro Sciences (IIVS), and the California Department of Pesticide Regulation (CDPR). According to EPA, the quarterly series will focus on the use of new approach methodologies (NAM), or alternative methods to reduce vertebrate animal testing, for risk assessment within EPA and CDPR. The first webinar in the series will take place on August 23, 2023, from 11:00 a.m.-12:30 p.m. (EDT). The webinar will cover recent updates from the Organization for Economic Cooperation and Development (OECD), including information about its developmental neurotoxicity in vitro test battery. Registration is open.
EPA notes that the Toxic Substances Control Act (TSCA) directs EPA to reduce and replace the use of vertebrate animals in the testing of chemical substances or mixtures to the extent practicable and scientifically justified. EPA must also promote the development and timely incorporation of alternative test methods or strategies that do not require new vertebrate animal testing. In 2018, EPA published a strategic plan to reduce the use of vertebrate animals in chemical testing.
By Lynn L. Bergeson and Carla N. Hutton
Research in the U.S. Environmental Protection Agency’s (EPA) Office of Research and Development (ORD) is organized around six highly integrated and transdisciplinary national research programs that are closely aligned with EPA’s strategic goals and cross-EPA strategies. Each program is guided by a Strategic Research Action Plan (StRAP) developed by EPA with input from its many internal and external partners and stakeholders. In October 2022, EPA published six StRAPs for fiscal years (FY) 2023-2026. EPA states that the StRAP for Chemical Safety for Sustainability (CSS) “is focused on addressing the pressing environmental and health challenge of a lack of sufficient information on chemicals needed to make informed, risk-based decisions.” The StRAP for CSS states that CSS will continue to:
- Develop the science needed to reduce, refine, and replace vertebrate animal testing consistent with EPA policies;
- Accelerate the pace of chemical assessment to enable our partners to make informed and timely decisions concerning the potential impacts of environmental chemicals on human health and the environment; and
- Provide leadership to transform chemical testing, screening, prioritization, and risk assessment practices.
Topic 1, Chemical Evaluation, includes three research areas, including emerging materials and technologies. The StRAP states that emerging materials and technologies often have unique physicochemical properties, warranting specialized approaches for evaluating hazard and exposure, and necessitating an evaluation of the environmental impacts of their use. In addition, investigation of novel products of synthetic biology, genome editing, and metabolic engineering is needed to support risk assessment of emerging biotechnology products. The emerging materials and technologies research area will develop, collate, mine, and apply information on emerging materials and technologies to support risk-based decisions, including potential impacts of disproportionately affected populations. It will address the additional data needed to characterize potential release of and exposure to these chemicals and materials, and subsequent environmental impacts of emerging materials on humans and ecological species. The research area will also address relevant cross-cutting priorities related to cumulative impacts and environmental justice potentially associated with incidental exposures.
By Lynn L. Bergeson and Carla N. Hutton
The U.S. Environmental Protection Agency (EPA) announced on November 10, 2022, that it is requesting nominations of prospective candidates for membership on the Science Advisory Committee on Chemicals (SACC) established under the Toxic Substances Control Act (TSCA). 87 Fed. Reg. 67898. Any interested person or organization may nominate qualified persons to be considered for appointment to the SACC. Individuals may also self-nominate. Nominations are due December 12, 2022.
SACC serves as a scientific peer review mechanism of EPA’s Office of Chemical Safety and Pollution Prevention (OCSPP). According to EPA, SACC provides independent scientific advice and recommendations to EPA on the scientific basis for risk assessments, methodologies, and pollution prevention measures and approaches for chemicals regulated under TSCA. Currently, there are 17 SACC members, with eight membership terms that will expire over the next year.
EPA states that its “rigorous scientific peer review processes ensure all Agency decisions are founded on credible science and data. Science provides the foundation for EPA policies, actions and decisions made on behalf of the American people.”
To be considered, all nominations should include the following information:
- Current contact information for the nominee (including the nominee’s name, organization, current business address, e-mail address, and daytime telephone number);
- The nominee’s disciplinary and specific areas of expertise;
- Research activities;
- Recent service on other federal advisory committees and national or international professional organizations; and
- When available, a biographical sketch of the nominee, indicating current position and educational background.
EPA states that it is seeking nominations from individuals who have demonstrated high levels of competence, knowledge, and expertise in scientific and other technical fields relevant to chemical safety and risk assessment. EPA seeks nominees with expertise in a variety of disciplines and focus areas, including human health and ecological risk assessment, biostatistics, epidemiology, pediatrics, physiologically based pharmacokinetics (PBPK), toxicology and pathology (including neurotoxicology, developmental/reproductive toxicology, and carcinogenesis), and chemical exposure pathways to susceptible life stages and subpopulations (women, children, and other potentially exposed subpopulations).
EPA states that nominees should have backgrounds and experiences that would contribute to the diversity of scientific viewpoints on the committee -- including professional experiences in government, labor, public health, public interest, animal protection, industry, and other groups -- and as the EPA Administrator determines to be advisable (e.g., geographical location; social and cultural backgrounds; and professional affiliations).
By Lynn L. Bergeson and Carla N. Hutton
The U.S. Environmental Protection Agency’s (EPA) New Chemicals Program will host a webinar on October 18, 2022, on EPA’s process for assessing the potential risks of new chemicals under Section 5 of the Toxic Substances Control Act (TSCA) and the types of data EPA considers in this assessment. The webinar will cover examples of quantitative and qualitative data unlikely to be accepted for engineering assessment, considerations EPA makes when evaluating data, and clarifications of common misconceptions in EPA’s new chemical assessments.
As reported in our June 27, 2022, memorandum, in June 2022, EPA announced a broad outreach effort to describe to stakeholders how EPA evaluates engineering data (i.e., data related to environmental release and worker exposure) provided for new chemical submissions and common issues that cause EPA to have to reconduct risk assessments (“rework”). The goal of this effort is to prevent delays of EPA’s new chemical reviews caused by rework.
This will be the second in a series of webinars intended to increase the efficiency and transparency of EPA’s new chemical determinations. As reported in our July 28, 2022, memorandum, in July 2022, EPA hosted the first webinar, analyzing common issues that cause EPA to have to rework risk assessments. Meeting materials are available for those who missed the first webinar.
By Lynn L. Bergeson and Carla N. Hutton
On August 25, 2022, the U.S. Environmental Protection Agency (EPA) announced that registration was open for the 2022 Conference on the State of the Science on Development and Use of New Approach Methods (NAM) for Chemical Safety Testing. EPA notes that there will be limited availability in person at EPA headquarters in Washington, DC, on October 12-13, 2022, and a virtual option will also be available. Conference topics include:
- Variability and Relevance of Traditional Toxicity Tests;
- Evolution of Validation and Scientific Confidence Frameworks to Incorporate 21st Century Science; and
- Breakout groups discussing Variability of Traditional Toxicity Tests, Relevance of Traditional Toxicity Tests, and Feedback on EPA Scientific Confidence Framework.
EPA asks that attendees register for the NAMs conference before October 7, 2022.
On October 18, 2022, EPA will provide training on the Computational Toxicology (CompTox) Chemicals Dashboard, which is part of a suite of databases and web applications developed by EPA to support the development of innovative methods to evaluate chemicals for potential health risks. The computational toxicology tools and data in the Dashboard help prioritize chemicals based on potential health risks. Specifically targeted for decision-makers, the training will provide:
- An overview of the Dashboard content and function;
- Application-oriented use-case demonstrations in the areas of general use, hazard/bioactivity, exposure/absorption, distribution, metabolism, and excretion (ADME)-in vitro to in vivo extrapolation (IVIVE), and chemistry; and
- Opportunities for participatory learning and engagement.
The training will offer information about the latest release of the Dashboard and how it can be used to gather actionable information about chemical properties and risks through case examples, demonstrations, and hands-on exercises. Registration is now open (attendees must register for the training portions individually):
By Lynn L. Bergeson and Carla N. Hutton
The U.S. Environmental Protection Agency (EPA) announced on August 11, 2022, that it updated the Safer Chemical Ingredients List (SCIL), “a living list of chemicals by functional-use class that EPA’s Safer Choice program has evaluated and determined meet the Safer Choice Standard.” EPA added 22 chemicals to the SCIL. EPA states that to expand the number of chemicals and functional-use categories on the SCIL, it encourages manufacturers to submit their safer chemicals for review and listing on the SCIL. In support of the Biden Administration’s goals, the addition of chemicals to the SCIL “incentivizes further innovation in safer chemistry, which can promote environmental justice, bolster resilience to the impacts of climate change, and improve water quality.” According to EPA, chemicals on the SCIL “are among the safest for their functional use.”
EPA also changed the status for one chemical on the SCIL and will remove the chemical from the list in one year “because of a growing understanding of the potential health and environmental effects.” According to EPA, the chemical was originally listed on the SCIL based on data from a closely related substance that EPA marked with a grey square earlier this year. EPA’s process for removing a chemical from the SCIL is first to mark the chemical with a grey square on the SCIL web page to provide notice to chemical and product manufacturers that the chemical may no longer be acceptable for use in Safer Choice-certified products. A grey square notation on the SCIL means that the chemical may not be allowed for use in products that are candidates for the Safer Choice label, and any current Safer Choice-certified products that contain this chemical must be reformulated unless relevant health and safety data are provided to justify continuing to list the chemical on the SCIL. EPA states that the data required are determined on a case-by-case basis. In general, data useful for making such a determination provide evidence of low concern for human health and environmental impacts. Unless information provided to EPA adequately justifies continued listing, EPA then removes the chemical from the SCIL 12 months after the grey square designation.
According to EPA, after this update is made, there will be 1,055 chemicals listed on the SCIL. EPA is committed to updating the SCIL with safer chemicals on a regular basis. EPA states that the SCIL is a resource that can help many different stakeholders:
- Product manufacturers use the SCIL to help make high-functioning products that contain safer ingredients;
- Chemical manufacturers use the SCIL to promote the safer chemicals they manufacture;
- Retailers use the SCIL to help shape their sustainability programs; and
- Environmental and health advocates use the SCIL to support their work with industry to encourage the use of the safest possible chemistry.
EPA’s Safer Choice program certifies products containing ingredients that have met the program’s rigorous human health and environmental safety criteria. The Safer Choice program allows companies to use its label on products that meet the Safer Choice Standard. The EPA website contains a complete list of Safer Choice-certified products.
By Lynn L. Bergeson and Carla N. Hutton
The U.S. Environmental Protection Agency’s (EPA) New Chemicals Program held a webinar on July 27, 2022, to provide an in-depth look at its analysis of common issues that cause EPA to have to reconduct risk assessments (“rework”) of new chemicals. In June 2022, EPA announced a broad outreach effort to describe and to discuss with stakeholders how EPA evaluates engineering data (i.e., data related to environmental release and worker exposure) provided for new chemicals submissions under the Toxic Substances Control Act (TSCA) and common issues that cause EPA to have to rework risk assessments for these submissions. EPA has posted the meeting slides online.
During the webinar, EPA presented an example of a rework case. According to EPA, from its analysis, it observes that:
- Information on material balance parameters, environmental releases, environmental release media, and engineering controls cause nearly 80 percent of all rework;
- In most cases, companies provide additional information that deviates from EPA model defaults and assumptions; and
- Companies often lack understanding on what information is needed for a Section 5 engineering assessment, including the level of detail needed to support their statements relating to environmental release and worker exposure.
As noted in the meeting slides, EPA plans to hold two additional webinars in fall 2022 that will cover:
- How EPA evaluates quantitative and qualitative information, with examples on the level of detail needed to support the submitted information to be accepted by EPA; and
- The types of information commonly missing in Section 5 submissions, how EPA evaluates environmental release information on sites not controlled by the submitter, and their impact on engineering assessment.
More information is available in our July 28, 2022, memorandum.
By Lynn L. Bergeson and Carla N. Hutton
On March 23, 2022, the U.S. Environmental Protection Agency (EPA) held a webinar on “Biofuel Premanufacture Notices: New Chemical Risk Assessment and Applications of Tools and Models.” As reported in our January 24, 2022, blog item, in January 2022, EPA announced an effort to streamline the review of new biobased or waste-derived chemicals that could displace current, higher greenhouse gas (GHG)-emitting transportation fuels. EPA states that to support this effort, it is offering outreach and training to stakeholders interested in biofuels. According to EPA, the bi-weekly webinar series includes reviewing requirements under the Toxic Substances Control Act (TSCA), outlining the streamlined approaches for risk assessments and risk management actions, and providing information on how to navigate the new chemicals premanufacture notice (PMN) process. EPA provided background and outlined the following challenges for each risk assessment conducted:
- Chemistry Assessment:
- Fuel stream and related substances are broad in number and scope, especially with the addition of current biobased and waste feedstock blends; they can be class 1, class 2, or chemical substances of unknown or variable composition, complex reaction products, and biological materials (UVCB) substances;
- Many petroleum-derived fuel streams are on the original TSCA Inventory and there are very little data associated with them; and
- Complete characterization of the new chemical substance is often unavailable;
- Environmental Fate and Transport Assessment:
- Analysis of constituents may not represent the properties of the new chemical substance;
- Engineering Assessment: Environmental Releases:
- EPA’s release assessment analyzes each manufacturing, processing, and use operation and determines the sources/activities that can result in releases to the environment. These release estimates are used to estimate exposure estimates for ecological and human receptors;
- Examples of release data: (1) Measured release data; (2) Measured release data for a “surrogate” chemical; (3) Modeled release estimates; and
- Release estimates have limitations -- examples:
- Lack of appropriate model/method to estimate releases from specific industrial activities (e.g., storage tank emissions); and
- Limitation in certain release models (e.g., limited to a vapor pressure threshold of 35 torr);
- Engineering Assessment: Occupational Exposures:
- The occupational exposure assessment estimates the magnitude, frequency, and duration of exposures to the new chemical substance at the workplace;
- Worker inhalation and dermal exposures are expected throughout the lifecycle of the new chemical substance (e.g., manufacturing, processing, use); and
- Exposure models do not account for some engineering controls (vapor capture/reduction);
- Exposure Assessment: General Population and Consumer Exposures:
- The occupational exposure assessment estimates the magnitude, frequency, and duration of exposures to the new chemical substance for the general population and consumers via inhalation and drinking water pathways; and
- The confidence of the exposure estimates are affected by:
- Assumptions, limitations, and areas of uncertainty in the fate and engineering analyses; and
- Inherent uncertainties of the exposure parameters and assumptions for the estimation of the general population and consumer exposures;
- Hazard Assessment:
- Data on the new chemical substance or an analogous biofuel are preferred, but few submissions include toxicological or composition data;
- EPA often lacks acute/chronic environmental test data on the new chemical substance and the analogous substances; and
- There are challenges in performing read-across approaches and route-to-route extrapolations with analogous substances of variable composition.
For biofuel PMNs, EPA has started generating one report that combines the results of each of the above assessments. The final webinar in the series will be held April 6, 2022, on new chemicals risk management actions, including TSCA Section 5 orders and significant new use rules (SNUR).
By Lynn L. Bergeson
On October 1, 2021, EPA announced a series of virtual meetings of the Board of Scientific Counselors (BOSC) Chemical Safety for Sustainability and Health and Environmental Risk Assessment (CSS HERA) Subcommittee to review recent progress and activities of the Chemical Safety Analytics (CSA) and Emerging Materials and Technologies (EMT) research areas. Meetings are open to the public, and EPA accepted comments until November 3, 2021.
The initial meeting will be held over a two-day period via videoconference on November 4 and 5, 2021, 12:00 p.m. to 5:00 p.m. (EDT). Registration was required by November 3, 2021. The following meetings are also scheduled:
- BOSC Deliberation Videoconference: November 18, 2021, 11:00 a.m. to 2:00 p.m. (EST) -- Registration is required by November 17, 2021.
- Final BOSC Deliberation Videoconference: December 10, 2021, 11:00 a.m. to 2:00 p.m. (EST) -- Registration is required by December 9, 2021.
Meeting times are subject to change.
After reading the article below by Jeffery Morris, former Director of the U.S. Environmental Protection Agency’s (EPA) Office of Pollution Prevention and Toxics (OPPT), we were inspired to post it. We appreciate having the opportunity to share his analysis with our audience.
TSCA as a Gap-Filling Statute: Potentially Exposed and Susceptible Subpopulations
By Jeffery Morris, PhD
In its response to public comments on the scope documents for its next twenty chemical risk evaluations conducted under the Toxic Substances Control Act (TSCA), the US Environmental Protection Agency (EPA) has asserted that TSCA is a “gap-filling statute” for the regulation of chemical substances in the United States (US EPA, Summary of Public Comments Received on the Draft Scopes of the Risk Evaluations for Twenty Chemical Substances Under the Toxic Substances Control Act (TSCA), August 2020, p. 13). This assertion relates to the regulatory nexus between TSCA and other federal statutes. At issue regarding regulatory nexus is whether TSCA’s role is to: (1) fill gaps where issues are not addressed by other laws that regulate chemicals1, (2) serve as the nation’s primary and preeminent statute for chemicals, or (3) operate somewhere between these two positions. Inherent in the TSCA-as-gap-filler position is the view that federal laws should work together to advance the public welfare, and that different environmental statutes have their own strengths in how they govern the impact of chemicals on people and the environment.
TSCA requires the consideration of potentially exposed or susceptible subpopulations in the EPA’s evaluation of chemicals. While TSCA is not the only environmental law with provisions for susceptible or vulnerable subpopulations, the direct, repeated emphasis across multiple sections of the law that the EPA consider potentially exposed or susceptible subpopulations may be unique in US environmental law. Therefore, how the EPA meets this requirement with respect to other laws’ treatment of such populations is an important consideration for regulatory nexus. Key questions regarding regulatory nexus and TSCA’s role are how to go about identifying whether other statutes leave gaps in this area for TSCA to fill and if they do, how those gaps should be filled in the EPA’s chemical evaluations.
The recently released final scope documents and the accompanying response-to-comments document do not fully answer these questions, including regarding comments that have been raised about how the EPA will apply exposure and susceptibility considerations to people living in communities located near high concentrations of chemicals-related activity. My hope is that exploring these questions now can help inform a path forward for further addressing comments the EPA has received on potentially exposed or susceptible subpopulations as the twenty draft risk evaluations are developed, as well as in scope documents for future chemicals brought into the TSCA prioritization process.
In its response to scope document comments, the EPA makes two important statements regarding the regulatory nexus issue as applied to potentially exposed or susceptible subpopulations. The first, on page 13, is that “EPA believes that coordinated action on exposure pathways and risks addressed by other EPA-administered statutes and regulatory programs is consistent with statutory text and legislative history, particularly as they pertain to TSCA’s function as a ‘gap-filling’ statute ….” In the second statement, also on page 13, the EPA adds that “[t]o the extent that specific exposure pathways are not under the jurisdiction of other EPA-administered statutes and associated regulatory programs, EPA plans to evaluate those exposures in the risk evaluations for the individual substances.”
The first statement’s focus on “coordinated action” between laws and regulations with respect to chemical evaluation and management is a crucial consideration for regulatory nexus. Coordination by the EPA’s Office of Chemical Safety and Pollution Prevention (OCSPP), which administers TSCA, with other EPA offices that manage statutes that address chemicals, as well as with other federal agencies that implement laws impacting chemicals, is good government practice. What is missing from the final scope documents, and therefore would be a valuable addition to the chemical-specific dockets, is a detailed description of the type of coordination cited in the response to comments. Ideally, this description would appear in the scope documents, but for these twenty chemicals an addition to the dockets would be helpful. For example, the EPA could strengthen its explanation of whether potential exposures or susceptibilities are based on geography (e.g., exposures are higher in a particular location), biology (e.g., a particular population has a genetic or otherwise biologically based predisposition to suffer adverse effects from exposure to a chemical), or cultural/societal factors (e.g., a cultural or community practice results in exposure potential greater than in the general population, or an attribute of the subpopulation’s location in society, such as having low income or poor access to health care, creates susceptibilities to adverse effects from chemical exposure).
Because some comments on community exposures refer specifically to 1,3-butadiene, it is a useful example to illustrate the challenges and opportunities presented by the coordination the EPA is conducting within the regulatory nexus construct; it also can illustrate what I mean by a detailed description of cross-office coordination on potentially exposed or susceptible subpopulations. This example looks at just one of 1,3-butadiene’s uses: in the production of tires. Under its Clean Air Act (CAA) authority, the EPA’s Office of Air and Radiation (OAR) conducted a Residual Risk Assessment for the Rubber Tire Manufacturing Source Category in Support of the 2020 Risk and Technology Review Final Rule (EPA-HQ-OAR-2019-0392-0047, February 2020) that includes 1,3-butadiene within this source category, among numerous other chemical substances designated as hazardous air pollutants (HAP). This assessment supports a July 24, 2020, final rule, National Emission Standards for Hazardous Air Pollutants: Rubber Tire Manufacturing Residual Risk and Technology Review (EPA-HQ-OAR-2019-0392; FRL 10008-48-OAR, 85 FR 44752, July 24, 2020).
The coordination challenge, therefore, is to crosswalk the CAA review, which covers numerous HAPs within one sector, with a TSCA risk evaluation covering the conditions of use of a single HAP chemical across multiple sectors. On page 49 of the 1,3-butadiene TSCA scope document, the EPA states that air emission pathways are covered under the CAA (Final Scope of the Risk Evaluation for 1,3-Butadiene, EPA Document # EPA-740-R-20-011, August 2020). It would be useful for the 1,3-butadiene record to include a table and/or narrative that describes how, for its TSCA coordination on the consideration of potentially exposed or susceptible subpopulations, OCSPP evaluated the 1,3-butadiene conditions of use against the respective source category-based and any other analyses conducted by OAR that included 1,3-butadiene. Such a crosswalk could serve as a best practice for application of regulatory nexus analysis in the implementation of TSCA. It would also aid in transparency to the public around a very complex but important concept: that although different environmental statutes may use different approaches (e.g., sector or source category versus individual chemical analysis), it is possible to coordinate their respective contributions to chemical evaluation and management so that, if gaps exist, TSCA can play its appropriate role in health and environmental protection.
For instance, OAR’s 2020 final rule states that “the percentage of the population potentially impacted by Rubber Tire Manufacturing emissions is greater than its corresponding nationwide percentage for: African Americans (25 percent for the source category compared to 12 percent nationwide) and below the poverty level (21 percent for the source category compared to 14 percent nationwide)” (page 44759). Strong coordination between TSCA and the CAA would suggest that such information obtained through CAA activities would be helpful to OCSPP in determining how to address the “potentially exposed or susceptible subpopulations” considerations required under TSCA section 6, including as they may apply to TSCA’s gap-filler role in addressing comments to the 1,3-butadiene scope document concerning disproportionate exposure to communities located near high concentrations of chemicals-related activity.
This consideration leads to the EPA’s statement in its response-to-comments document that where there is not overlap with another regulatory jurisdiction, the EPA will evaluate the exposures. Using the above TSCA-CAA coordination example for 1,3-butadiene, a question for OCSPP could be whether the TSCA requirement that the EPA consider potentially exposed or susceptible subpopulations in its risk evaluations is covered by the work done by OAR on 1,3-butadiene, specifically with respect to commenters’ input on community-based impacts. One would assume “covered” to mean that this particular aspect of TSCA’s potentially exposed or susceptible subpopulations requirement has been evaluated and addressed in OAR’s CAA activities, and therefore can be excluded from the 1,3-butadiene risk evaluation. However, if the CAA has not addressed this particular TSCA requirement in a manner or to an extent intended by the best read of TSCA’s language regarding the consideration of those potentially exposed or susceptible subpopulations in a particular chemical risk evaluation, then there exists a gap that TSCA, as a gap-filling statute, should address.
The manner in which a TSCA risk evaluation fills any identified gaps is also important. This again will require careful and transparent coordination and analysis between statutes. In its chemical risk evaluations, EPA would presumably want to fill gaps in ways that meet the specific requirements of TSCA for potentially exposed or susceptible subpopulations, without doing so in a manner that is at odds with other statutes’ treatment of a chemical substance under TSCA evaluation. Not only would this careful gap filling be in general sound government practice, but it also would help avoid difficulties if the risk evaluation identifies unreasonable risks that the EPA determines, under TSCA section 9, should be addressed under a law other than TSCA.
The 1,3-butadiene example shows how greater explanation, preferably in scoping documents, on how the EPA coordinates among its offices and other agencies to make regulatory nexus decisions for TSCA risk evaluations can not only provide greater transparency to the public on individual chemical evaluations, but also can inform broader discussions on regulatory nexus by showing how such coordination can identify gaps that TSCA is best situated to fill. For some chemicals, it may be the case that other statutes have already adequately assessed the risks to potentially exposed or susceptible subpopulations, obviating the need for additional analysis in a TSCA risk evaluation. However, the mere existence of another statute with jurisdiction over a particular environmental pathway or human exposure scenario for a chemical substance subject to TSCA review should not lead to an a priori assumption that there is not an evaluation gap for TSCA to fill. Any assumptions about other statutes’ coverage of TSCA’s chemical evaluation requirements should be explored, tested, and fully described in TSCA chemical scope documents or elsewhere in the risk evaluation record. This is particularly important with potentially exposed or susceptible subpopulations, given TSCA’s unique approach to requiring their consideration in chemical prioritization, evaluation, and management. I would argue that a good starting point for articulating TSCA’s gap-filling role is in the application of these requirements to people living near high concentrations of chemicals-related activity.
1 By “chemicals” I refer in this article to chemicals regulated under TSCA, and not to chemicals that are regulated under other federal statutes, such as pesticides, drugs, and food additives.