The U.S. Environmental Protection Agency (EPA) has released draft TSCA risk evaluations for dibutyl phthalate (DBP) and di(2-ethylhexyl) phthalate (DEHP), finding unreasonable risks to human health and the environment. The assessments, published 4 June 2025, are now open for public comment and peer review—setting the stage for sweeping regulatory consequences across supply chains.
Unreasonable risks identified for workers and ecosystems
EPA's preliminary evaluation concluded that DBP poses risks in 25 of 40 analysed conditions of use (COUs), including exposures to workers and consumers, and one to the environment. Meanwhile, DEHP was found to present unreasonable risks in 33 COUs, particularly concerning occupational exposure and multiple environmental release scenarios.
Importantly, the evaluations do not account for the use of personal protective equipment (PPE), though EPA notes PPE may help mitigate some risks. No general population risks were identified under current assumptions, nor were cumulative exposure thresholds exceeded for either substance.
Phthalates under the regulatory spotlight
DBP and DEHP are part of a five-chemical phthalate group under TSCA scrutiny. Alongside these, evaluations are progressing for butyl benzyl phthalate (BBP), diisobutyl phthalate (DIBP), and dicyclohexyl phthalate (DCHP). These substances are commonly used as plasticisers across automotive, medical, consumer, and electronics sectors.
In addition to the two draft evaluations, EPA released several cross-cutting technical support documents (TSDs), including a revised cumulative risk analysis and draft carcinogenicity assessment. These documents are intended to harmonise regulatory decision-making across the group.
Key deadlines and next steps
Public comments are due by 4 August 2025, while comments intended for consideration by the Science Advisory Committee on Chemicals (SACC) must be submitted by 21 July 2025 to the peer review docket (EPA-HQ-OPPT-2024-0551). A virtual peer review meeting will take place from 4–8 August 2025, where evaluations for DBP, DEHP, and DCHP, as well as cross-cutting documents, will be scrutinised.
EPA emphasised that no further peer review will be conducted for BBP and DIBP, as upcoming evaluations will incorporate SACC recommendations from the August session.
Implications across the manufacturing value chain
The findings may have significant regulatory and commercial consequences for sectors reliant on phthalate-based materials. Companies may need to revise their exposure assessments, product formulations, or supply chain transparency measures ahead of final determinations.
Given the risk characterisations and the precedent for future evaluations, this draft release underscores the need for proactive compliance strategies and regulatory engagement across the chemicals and manufacturing industries.
