The actions address different parts of chemical safety review. One is an interim framework using three-dimensional human airway tissue and digital modeling to assess respiratory irritation from certain surfactants. The other is the internationally recognized Globally Harmonized System, or GHS, mixtures equation, which can help estimate acute oral toxicity for some pesticide formulations from data on their ingredients.

This is a change in review methods, not a new consumer-safety standard. The announcement does not impose a product ban, announce a recall, change an exposure limit or declare all soaps, detergents, cleaners or pesticides safe or low-risk.

How the surfactant method works

Surfactants are chemicals that help liquids mix, spread or wet surfaces. They are used in consumer products such as soaps, detergents and cleaners, as well as in industrial and workplace settings.

EPA’s August 27 technical memorandum describes an interim approach for certain new chemical substances that uses MucilAir, a three-dimensional human airway epithelial tissue model. EPA exposed the human-derived tissue to five concentrations of each reference chemical for 24 hours and evaluated biomarkers associated with respiratory irritation, including inflammatory signals, cell damage, barrier integrity and cilia activity.

The initial reference chemicals are Triton X-100, a nonionic surfactant, and oleoyl sarcosine, an anionic surfactant. EPA says it will expand the approach as additional data become available for structurally diverse surfactant analogues.

After deriving points of departure from the tissue experiments, EPA used its Multiple-Path Particle Dosimetry, or MPPD, version 2.0 model to estimate human-equivalent concentrations. In plain language, the model helps estimate where inhaled particles may deposit in the respiratory tract under representative particle-size and use scenarios.

EPA’s memorandum says the approach is intended to reduce uncertainty associated with differences between rat and human respiratory systems. It remains an interim method and does not automatically replace every animal study or determine every regulatory decision.

How the pesticide calculation works

The second action concerns the use of the GHS mixtures equation for some pesticide formulations. The equation combines toxicity information for known ingredients to estimate the acute oral toxicity of a finished mixture. That can allow a registrant to ask EPA to replace a traditional acute oral animal study when the formulation is expected to be minimally toxic by the oral route.

The pathway is not a blanket exemption. EPA’s submission materials say registrants must provide formulation details, ingredient data, calculated values and supporting acute-toxicity information. The agency may evaluate the calculation alongside existing animal-study data, and acceptance depends on whether the method fits the product and the evidence is sufficient.

EPA’s strategic-vision materials cite a retrospective analysis of 671 formulations: 620 agrochemical formulations and 51 antimicrobial cleaning products. Across all four EPA acute oral Toxicity Categories, the overall concordance between calculated and observed results was 55%. Concordance rose to 82% for mixtures with predicted LD50 values above 500 milligrams per kilogram and reached 87% for mixtures predicted to fall in acute oral Toxicity Category IV.

Those figures provide validation context for the method. They are not a guarantee that the equation will accurately classify every future pesticide mixture.

Why EPA is moving in this direction

The two approaches fit EPA’s stated goal of eliminating remaining mammalian testing by 2035. The agency says that goal is consistent with its January 2026 recommitment and with the Toxic Substances Control Act’s requirement that EPA promote methods that reduce, refine or replace vertebrate animal testing when they provide information of equivalent or better scientific quality and relevance.

EPA groups these tools under the term new approach methodologies, or NAMs. The category includes human-cell and tissue systems, computer models, read-across methods and calculations based on existing chemical information.

The GHS mixtures equation itself is not new. EPA launched a pilot program in 2016 to evaluate its usefulness for pesticide toxicity assessments, closed the submission period for new data in 2019 and later analyzed the submitted acute oral data. The August 27 announcement places that work within the agency’s current push to expand non-animal methods.

What changes for consumers and workers

Consumers should not expect immediate changes to household-product labels, pesticide instructions or approved uses based on this announcement alone. The agency did not announce a recall, change a product’s legal use or issue a new exposure limit.

Workers and employers should continue following applicable product labels, workplace requirements and safety instructions. Any future effect on workplace controls would depend on the specific chemical, the evidence EPA accepts and the rules or risk assessments governing that use.

Manufacturers and pesticide registrants may gain additional ways to support EPA reviews without commissioning some new animal studies. But those options remain limited by the method’s scope and by EPA’s case-by-case review of submitted evidence.

What to watch next

The next important signals will be EPA technical documents, review decisions and guidance showing whether the surfactant framework expands beyond Triton X-100 and oleoyl sarcosine. For pesticides, watch how often registrants submit GHS-equation calculations and whether EPA accepts them in place of additional acute oral studies for qualifying formulations.

The broader significance is methodological. Selected parts of chemical review are moving toward human-relevant tissue models, digital dosimetry and ingredient-based calculations. The August 27 announcement does not, by itself, change what products consumers may buy or how they must be used.

Sources

• EPA mixtures equation pilot program

Released August 28, 2026, the draft says 19 of the evaluated conditions of use contribute to unreasonable risk for workers. Thirteen of those also contribute to risk for occupational non-users, people who work near a process or product but do not directly handle the chemical. EPA also preliminarily identified unreasonable risk for one consumer cleaner or degreaser use.

The release is not a ban, recall or immediate restriction. It is a draft assessment under the Toxic Substances Control Act, or TSCA. EPA will take public comments, consider scientific peer-review input and then issue a final evaluation.

What chemical is under review?

Trans-1,2-dichloroethylene, identified as CASRN 156-60-5, is a colorless, highly flammable liquid used primarily as a solvent, cleaning agent, degreaser, processing aid and ingredient in some formulations. EPA’s background materials say reported production volume was between 1 million and 5 million pounds per year in the 2024 Chemical Data Reporting cycle.

The evaluation covers uses including industrial and commercial cleaning and degreasing, processing and chemical manufacturing, semiconductor-related operations, propellants and blowing agents, adhesives and sealants, lubricants and greases, refrigerants, spot cleaners and stain removers. EPA evaluates the chemical across its lifecycle, including manufacturing, processing, distribution, use and disposal.

The findings are tied to defined conditions of use and exposure scenarios. They do not mean every product containing the chemical, every semiconductor facility or every worker faces the same level of risk.

Who may face exposure?

Workers may encounter the solvent during manufacturing, processing, distribution, industrial or commercial use and disposal. Occupational non-users may be exposed in nearby work areas even when they do not directly handle the chemical.

EPA’s draft says the preliminary worker and occupational non-user findings are driven primarily by inhalation exposure. The Federal Register notice also describes potential dermal exposure routes, but EPA’s summary says it did not identify unreasonable risk from dermal exposure for workers, occupational non-users or consumers.

Consumers may encounter trans-1,2-dichloroethylene during the intended use of products such as cleaners, degreasers or propellants. The preliminary consumer finding is limited to one cleaner or degreaser use and is based on acute and intermediate non-cancer inhalation exposure.

What EPA found

EPA’s risk-evaluation page says it assessed 25 conditions of use and preliminarily found that 20 significantly contribute to unreasonable risk to human health. Nineteen conditions contribute to risk for workers, and 13 of those also contribute to risk for occupational non-users. One consumer cleaner or degreaser use contributes to the preliminary risk determination.

EPA said five conditions of use did not significantly contribute to the preliminary unreasonable-risk determination. Those included distribution in commerce, disposal, laboratory chemical use, use in semiconductor and photovoltaic processing aids, and consumer use of polymer-foam propellants.

The draft did not preliminarily identify unreasonable risk to the general population, including fenceline communities, or to the environment under the conditions evaluated. That does not mean there is no exposure or no hazard outside those scenarios. It means EPA did not make an unreasonable-risk finding for those categories in this draft analysis.

The assessment also does not establish that every person exposed to the chemical will develop a specific disease. Its conclusions concern modeled and documented exposure and hazard information under particular uses.

Why nothing changes immediately

Existing protections remain in place while EPA completes the review. Releasing the draft does not alter current safeguards, regulations or risk-management measures. The draft itself does not prohibit the chemical, require a recall or impose new controls on businesses or consumers.

Under TSCA, EPA must use the final risk evaluation to determine whether the chemical presents an unreasonable risk under its conditions of use. If the agency continues to find unreasonable risk, it could later propose risk-management measures under Section 6(a). Those measures would be a separate regulatory step, and the draft does not determine what controls EPA might ultimately propose.

What happens next?

Public comments on the draft are due October 26, 2026. The Federal Register notice identifies the EPA docket as EPA-HQ-OPPT-2018-0465 and explains how to submit comments through Regulations.gov.

The draft’s supporting technical documents have also gone through the Science Advisory Committee on Chemicals process. EPA held a preparatory public meeting July 23, 2026, and a SACC meeting August 3-7, 2026, to discuss the technical materials supporting several draft chemical evaluations, including trans-1,2-dichloroethylene.

EPA says it will consider public comments and SACC peer-review input before issuing a final evaluation. For workers and employers involved in solvent cleaning, degreasing, chemical processing or related manufacturing, the key question is whether the preliminary findings survive that review and lead to later proposed controls. For consumers, the immediate takeaway is narrower: a product containing trans-1,2-dichloroethylene is not automatically banned or recalled because of this draft.

Sources

• EPA: Draft TSCA review announcement
• Federal Register: Notice of availability and request for comment
• Bloomberg Law: Semiconductor solvent review

The U.S. Chemical Safety and Hazard Investigation Board said a July 2025 inspection found significant thinning in the carbon-steel shell of G Tank at Nippon Dynawave Packaging’s mill in Longview, Washington. The inspection contractor recommended an internal inspection and repairs and warned of a high likelihood and consequence of failure.

The tank remained in service until it failed on May 26, 2026. The CSB said its investigation is ongoing and has not assigned final responsibility.

What the July inspection found

G Tank was an atmospheric storage tank holding approximately 1.2 million gallons. The July 2025 external-shell inspection found portions of the carbon-steel shell below the calculated minimum safe thickness — the amount of material the tank needed to safely contain its contents under its typical operating conditions.

The contractor recommended that Nippon Dynawave inspect the tank internally and repair the thinned areas. The report described G Tank as “not fit for continued service” unless it was repaired and cited a “high likelihood/consequence of failure,” the CSB said. Those statements were the contractor’s inspection conclusions, not a final federal finding of legal liability.

What happened after the warning

Nippon Dynawave conducted additional external inspections in October 2025 and February 2026. Both found that substantial portions of the shell remained below the calculated minimum safe thickness.

According to the CSB’s investigative update, the tank was not internally inspected or repaired, removed from service, or operated under reduced conditions before the collapse. The agency is examining why the tank remained in service after the initial warning and the two later inspection findings.

How the collapse unfolded

On the morning of May 26, a process upset required the mill to stop sending white liquor from G Tank to its digestor, where the chemical is used in pulp production. White liquor continued entering the tank from the mill’s recausticizing process, however, causing the level to rise to approximately 90% full by 6:22 a.m.

At approximately 7:09 a.m., G Tank catastrophically failed. The CSB said the collapse released approximately 900,000 gallons of extremely hot, highly caustic white liquor, reported at about 200 degrees Fahrenheit, into the surrounding courtyard and nearby buildings, where employees were gathered for morning meetings.

Eleven Nippon Dynawave employees were killed, and three others were seriously injured. Five additional employees and one firefighter suffered injuries that did not require inpatient hospitalization.

Several investigations remain separate

The CSB is examining the company’s mechanical-integrity, inspection and maintenance practices; decisions involving the inspection, repair or replacement of G Tank and other atmospheric storage tanks; operating conditions before the failure; emergency-response procedures; and applicable regulations and industry guidance. The CSB is an independent, nonregulatory federal agency. It does not issue citations or fines, but it can issue safety recommendations.

OSHA’s accident inspection opened on May 26 and remains listed as open. Washington’s Department of Labor & Industries is conducting a separate workplace-safety investigation that includes document reviews, witness interviews and a physical inspection of the site. L&I says it has 180 days by law to complete the investigation, although complex inspections can take the full period. After final findings are issued, the employer has 15 working days to appeal any violations.

Washington’s Department of Ecology is handling a separate environmental process. The agency issued a notice of violation containing an initial determination of 35 environmental violations connected to the release. Ecology said the white liquor reached storm drains, the mill’s wastewater treatment system and the Columbia River, with impacts continuing for up to eight days.

Nippon Dynawave has 30 days to respond or provide additional information before Ecology decides whether to issue a penalty or take other enforcement action. The notice is not itself a final penalty or completed enforcement action. Ecology said it may also seek recovery of state emergency-response costs and assess environmental damage.

What remains unresolved

The new federal update adds a major issue to the investigation: not only how the tank failed, but why it remained in service after an inspection contractor documented wall thinning below the calculated minimum safe thickness and recommended repairs and an internal inspection.

That record does not yet establish criminal, civil or regulatory liability. The CSB has not issued a final root-cause report, and OSHA and Washington Labor & Industries have not completed their workplace-safety investigations. Ecology’s 35 violations remain initial determinations pending the company’s response and the agency’s next action.

Nippon Dynawave has said it is cooperating with the investigations and will not speculate about the root cause before the facts are complete. The next milestones to watch are the final CSB report, OSHA and L&I findings, and Ecology’s response after the company’s 30-day window.

Sources

• U.S. Chemical Safety Board investigation update
• Associated Press report
• OSHA accident inspection record
• Washington Department of Ecology notice

The June 29, 2026 enforcement action centers on a Dec. 27, 2025 incident that OSHA says began when fresh and spent sulfuric acid were mixed, overpressurizing a tank and rupturing a supply line. The agency says about 1 million gallons were released and multiple employees were injured.

Who OSHA cited

The proposed penalties name BWC Terminals LLC, Coastal Environmental Solutions Inc. and One Way Environmental Services LLC. OSHA said BWC hired Coastal for hazardous waste cleanup, and Coastal subcontracted One Way to supply laborers for the remediation work.

OSHA’s penalty breakdown is uneven: One Way faces $3,045,452; Coastal faces $392,501; and BWC faces $82,750. Together, the proposed penalties total $3,520,703.

What OSHA says went wrong

According to the agency, investigators found failures tied to training, respirator protection, hazardous-waste cleanup safeguards and emergency response planning. OSHA said One Way sent workers into the cleanup without adequate training, respirator fit testing or other required safety measures. Coastal was cited for problems including a lack of training, a safety and health program, an emergency response plan and respirator-related deficiencies. BWC was cited for exposing workers to chemical burns, failing to provide hazmat training and having respirator deficiencies.

OSHA said the companies have 15 business days after receiving the citations to comply, request an informal conference or contest the findings before the Occupational Safety and Health Review Commission.

For workers and employers, the case is a reminder that OSHA can pursue facility owners, contractors and subcontractors when cleanup work is sent in without the basics: training, fit-tested respirators and a workable emergency plan. That issue has national relevance because spill response and industrial cleanup often depend on layered contractor chains.

Sources

• U.S. Department of Labor / OSHA release, June 29, 2026
• KPRC 2 Houston report, June 29, 2026
• Bloomberg Law Texas Brief, June 29, 2026