Chemical Processing Notebook: How Formaldehyde Processors Should Prepare for Shifting EPA Requirements

Formaldehyde has become a symbolic target of sorts as industry and regulators test the limits of U.S. chemical risk evaluation under the Toxic Substances Control Act, or TSCA. I reported on the U.S. Environmental Protection Agency's updated risk calculation draft on formaldehyde released Dec. 3 and reaction to its potential implications.

One interview that didn't make the article was a discussion with David Brew, a senior toxicologist with TRC Companies Inc. TRC provides environmental and engineering consulting services to various industries, including the chemical sector. I wanted to know how evolving formaldehyde regulations could impact safety precautions and practices within chemical processing operations.

The interview was informative enough to warrant its own article. The questions were in response to a LinkedIn post Brew published following the EPA draft announcement. 

With the 60-day comment period closing Feb. 2, Brew suggested organizations take several steps to prepare. While the Trump-led EPA is looking to ease some restrictions, Brew noted in his LinkedIn post that the memorandum confirms unreasonable risk remains the agency's conclusion and now places acute sensory irritation at the center of TSCA risk and future risk management decisions. He recommended that organizations begin mapping high-exposure tasks and formaldehyde peaks, compile available exposure data, conduct gap identification by comparing EPA's draft levels with existing limits, and submit focused, evidence-based comments that propose technically feasible risk management options.

Here's the email interview with Brew in its entirety.

CP: Can you expand on what that mapping process should entail and what, specifically, companies should be looking for?

DB: When we talk about mapping high-exposure tasks, we mean understanding exposures associated with each task and the length of time it is performed, not just monitoring eight-hour time-weighted averages (TWAs). To properly address this concern, organizations should consider a structured walkthrough of where formaldehyde is expected to be at each facility (i.e., raw material storage, charging and mixing, curing or pressing, downstream finishing, maintenance and waste handling).

To anticipate future regulatory requirements, companies should consider identifying the specific tasks where formaldehyde-containing solutions, resins or articles are handled, especially when formaldehyde vapor is present. Examples of these include opening containers or transfer lines, manual charging to reactors or mix tanks, molding or spraying resins, opening or unloading hot presses or drying ovens, paper rolling and drying, board cutting and drying, cleaning and maintenance of equipment and other startup or shutdown non-steady-state activities. For each of those tasks, it is important to understand how often and how long each task occurs, how close an operator or bystanders are to the source and what mitigation controls are in place (e.g., local exhaust, enclosures, automation, respiratory protection).

Historically, occupational exposure monitoring programs have focused on a limited set of eight-hour TWA samples collected for regulatory compliance, such as Occupational Health and Safety Administration (OSHA) standards, with relatively few short-term or other task-based measurements. More recently, EPA’s TSCA risk evaluation work has derived risk-only occupational exposure values that are intended to inform future risk-management decisions. EPA has calculated risk-only occupational exposure values of 0.17 ppm for acute sensory irritation and 0.11 ppm for eight-hour TWA and cancer in the TSCA risk evaluation materials. However, EPA has now calculated a revised draft acute occupational exposure value of 0.3 ppm based on sensory irritation that applies to all acute durations and serves as the short-term exposure benchmark. EPA states that managing acute sensory irritation at this level is protective of other effects, including cancer.

Therefore, companies will need to stay informed on emerging regulations. If EPA carries this value forward into risk management, more targeted, task-based monitoring at the highest-intensity activities is important to understand whether those short-term peaks are controlled.

CP: Based on your experience, are companies typically above or below the EPA's proposed limits right now?

DB: The answer to this question is highly facility-specific and depends on the particular processes, tasks and control measures in place at a given site. Historically, many facilities have focused on OSHA standards: 0.75 ppm as an eight-hour TWA and 2 ppm as a 15-minute short-term exposure limit (STEL) for formaldehyde. In 2016, the Frank R. Lautenberg Chemical Safety Act amended TSCA and created today’s risk-evaluation and risk-management framework for existing chemicals, including formaldehyde. Consequently, industries are required to understand both OSHA’s standards and EPA’s TSCA risk evaluations and any resulting risk-management rules, wherever applicable. All of [EPA’s] risk-only occupational benchmarks are lower than OSHA’s current 0.75-ppm TWA and 2-ppm STEL.

Any enforceable limits in a future [TSCA] Section 6 risk-management rule could differ once feasibility and other non-risk factors are considered. Facilities that were designed around OSHA exposure limits will likely need to re-evaluate their routine operations.

In practice, the limitation in many occupational exposure datasets is less about full-shift averages and more about the lack of short-term, task-based data for the highest-intensity activities. Maintenance personnel, contractors and other workers who are not formally classified as “formaldehyde operators” can still experience brief, elevated exposures when systems are opened or disturbed.

Under EPA’s updated TSCA approach, where a 0.3-ppm acute occupational exposure value based on sensory irritation is used as a short-term benchmark and applied across durations, those short-duration peaks become a central focus of the risk discussion, not just the daily time-weighted average.

CP: Is EPA tightening exposure limits by focusing on acute irritation, or are the new thresholds actually more lenient than current standards?

DB: The 0.3-ppm acute occupational exposure value that EPA is now proposing is higher than the earlier TSCA risk-only occupational exposure values of 0.17 ppm (acute) and 0.11 ppm (chronic), but all of these TSCA values remain lower than OSHA’s 0.75-ppm TWA and 2-ppm STEL.

EPA’s TSCA risk evaluation already concluded that formaldehyde presents an unreasonable risk to workers and consumers under its conditions of use; the updated draft risk calculation memorandum does not change that conclusion but revises the acute hazard value and risk calculations.

After EPA published the final TSCA risk evaluation for formaldehyde in January 2025, the agency released an Updated Draft Risk Calculation Memorandum, which requested public comment on an updated acute inhalation point of departure of 0.3 ppm and a corresponding revised draft occupational exposure benchmark. EPA states that this value is protective for all inhalation durations and effects, including cancer. It will inform TSCA risk-management decisions going forward. This value is more closely in line with other exposure limits like American Conference of Governmental Industrial Hygienists’ STEL and several EU occupational exposure limits.

Because EPA’s 0.3 ppm value is lower than OSHA’s numerical limits, some sites that currently comply with OSHA’s standards may require additional controls to align with TSCA’s acute benchmark. Conceptually, the updated memorandum places acute sensory irritation and short-term peaks at the center of TSCA’s risk calculation, making short-duration, high-intensity tasks key drivers for risk and for any eventual risk-management measures.

In practical terms, that points toward risk-management measures that emphasize task design and possible engineering controls to satisfy emerging TSCA risk-management requirements.