TSCA Risk Evaluations: Emerging Trends in EPA's Current Draft Reviews

The U.S. Environmental Protection Agency's (EPA) latest draft risk evaluations under the Toxic Substances Control Act (TSCA) provide important insight into how the Agency is currently assessing chemical risks and where it may focus future regulatory efforts. Recent draft evaluations for nine chemicals reveal several notable trends, including a continued emphasis on worker exposures, a limited number of environmental findings, and evolving approaches to risk characterization. 

Current Status of EPA's Risk Evaluations
EPA has released draft risk evaluations for several chemicals in 2026, including 1,1,2-trichloroethane, 1,2-dichloropropane, ethylene dibromide, HHCB, o-dichlorobenzene, p-dichlorobenzene, phthalic anhydride, TBBPA, and trans-1,2-dichloroethylene. Most of these evaluations have completed public comment periods and undergone some form of peer review by EPA's Science Advisory Committee on Chemicals (SACC). 

Under TSCA's risk evaluation provisions, EPA assesses whether a chemical substance presents an unreasonable risk to health or the environment under its conditions of use. If EPA ultimately determines that a chemical presents an unreasonable risk, the Agency proceeds to the risk management phase, where it develops regulations to address identified risks. 

The Numbers Behind the Draft Evaluations
Across the nine pending draft risk evaluations, EPA assessed 201 conditions of use (COUs). Of those, 119 were found to contribute to unreasonable risk. Notably, only one condition of use was identified as contributing to unreasonable risk to the environment, and none were found to contribute to unreasonable risk to the general population. Three of the evaluated chemicals included cancer risks that contributed to EPA's unreasonable risk determinations. 

The number of conditions of use contributing to unreasonable risk varies significantly among chemicals. For example, EPA preliminarily determined in the draft risk evaluation for phthalic anhydride that 38 out of 44 COUs evaluated contribute to unreasonable risk, while only four out of 24 COUs of TBBPA contribute to unreasonable risk. 

Continued Focus on Occupational Exposures
Perhaps the most significant trend emerging from the current draft evaluations is EPA's focus on occupational risks. The overwhelming majority of unreasonable risk findings involve workers and occupational non-users (ONUs), with inhalation exposures in the workplace serving as a primary driver of risk determinations. 

This pattern suggests that manufacturers, processors, and industrial users should continue paying close attention to workplace exposure controls, industrial hygiene practices, and respiratory protection programs. Companies subject to TSCA requirements may find that occupational exposure scenarios receive the greatest scrutiny in future risk evaluations and subsequent risk management actions. 

Cancer Risk Remains an Important Factor
Recently published draft evaluations also indicate that cancer risk continues to play a significant role in EPA's decision-making. Several chemicals received unreasonable risk findings driven, at least in part, by cancer concerns. As EPA continues to refine its risk assessment methodologies, carcinogenicity is likely to remain a key consideration in the Agency's evaluation process. 

Fewer Environmental and General Population Findings
Another notable trend is the relative absence of unreasonable risk findings for environmental receptors and the general population. Among the nine pending evaluations, EPA identified only a single condition of use that contributed to unreasonable risk to the environment and none that contributed to unreasonable risk for the general population. 

While each risk evaluation is highly fact-specific, these results reflect EPA's current focus on occupational exposure scenarios and may provide insight into the Agency's regulatory priorities moving forward. 

HHCB: A Notable Outlier
HHCB is an outlier among the other draft evaluations in that EPA preliminarily concluded that HHCB "does not present an unreasonable risk of injury to human health or the environment under the conditions of use." The Agency's preliminary determination applies broadly to workers, consumers, the general population, including subsistence fishers and Tribal populations, as well as aquatic and terrestrial ecological receptors. 

This outcome contrasts sharply with many of the other draft evaluations and demonstrates that while rare, EPA's review process can—in fact—result in findings of no unreasonable risk when the available data support that conclusion. It is still to be seen whether EPA finalizes the draft risk evaluation for HHCB as proposed and if so, whether the Agency’s final no unreasonable risk determination will be challenged by NGO groups.

Evolving Risk Evaluation Approaches
The current draft risk evaluations also suggest shifts in EPA's analytical approach. According to the draft reviews, margins of exposure (MOEs) are no longer being treated as bright-line indicators for risk determinations. Also, EPA is no longer consistently submitting complete risk evaluations for SACC peer review in the same manner as earlier evaluations but rather, has recently elected to only seek SACC review of technical support documents for some draft risk evaluations. These developments may signal broader changes in how EPA conducts and finalizes risk evaluations under TSCA and could be a potential vulnerability for the Agency in any future legal challenges. 

Looking Ahead
As EPA moves toward finalizing these risk evaluations, several important questions remain. Stakeholders are closely monitoring how the decision in East Fork Enterprises v. EPA may affect pending and finalized evaluations, how EPA will revise the TSCA Framework Rule, and whether the Agency will meet its February 2027 deadline for completing the remaining risk evaluations. Complicating things further, EPA has committed to applying the “whole chemical” approach—which the East Fork court held violates TSCA—until the TSCA Framework Rule is finalized in filings before the court United Steelworkers et al. v. EPA.  

The Agency's final decisions on these policies and approaches may shape the future direction of TSCA implementation and impact compliance obligations for chemical manufacturers, processors, and downstream users for years to come.