EPA Releases Draft Risk Evaluation for Dibutyl Phthalate (DBP) for Public Comment and Peer Review

In June 2025, the U.S. Environmental Protection Agency (EPA) released its draft risk evaluation for dibutyl phthalate (DBP), also known as 1,2-benzenedicarboxylic acid, 1,2-dibutyl ester (CAS No. 84-74-2) under the Toxic Substances Control Act (TSCA). The draft, and its technical support documents, are now open for a 60-day public comment period and scheduled for peer review by the Science Advisory Committee on Chemicals (SACC) from August 4–8, 2025. 

EPA designated DBP as a High-Priority Substance in December 2019 due to potential risks to human health and the environment. The draft evaluation is part of the agency’s ongoing review process under TSCA to determine whether existing chemicals present an unreasonable risk under current conditions of use (COUs). 

Key Findings from the Draft Risk Evaluation   

EPA’s preliminary determination concludes that DBP presents an unreasonable risk of injury to human health from 20 worker-related COUs, 4 consumer COUs, and one environmental COU. These findings are based on exposure scenarios that do not account for the use of personal protective equipment (PPE). However, the report notes that PPE could potentially reduce exposure and mitigate risks. 

Importantly, the agency did not identify unreasonable risks to the general population or from cumulative exposure across conditions of use. Additionally, no unreasonable risk was found for the 19 other COUs considered in the evaluation. 

Background and Use of DBP   

DBP is a colorless to pale yellow oily liquid, primarily used as a plasticizer in adhesives, sealants, paints, and coatings. Data from EPA’s 2016 Chemical Data Reporting indicates that U.S. production and import volumes of DBP range from 1 million to 10 million pounds per year. 

EPA's risk evaluation considers various COUs, including: 

• Use in adhesives and sealants 

• Paints and coatings 

• Laboratory chemicals 

• Commercial and consumer products such as floor coverings, furniture, lubricants, and light sticks 

Public Involvement   

Stakeholders can submit comments on the draft risk evaluation through docket EPA-HQ-OPPT-2018-0503 at regulations.gov. EPA encourages active participation from industry, environmental groups, and the public to inform its final risk determinations. 

Further engagement is expected as EPA finalizes the evaluation to ensure transparency and scientific rigor in the chemical safety process under TSCA.