The Environment Agency is considering prosecuting Huntsman Polyurethanes over emissions of benzene, a carcinogenic chemical with no safe exposure level, from its Teesside plant. The potential legal action follows a change to the site's emissions-control process that led to benzene being periodically released directly into the air, raising concerns from campaigners about health risks to workers and the local community and highlighting wider scrutiny of the plastics industry's environmental record.

Huntsman decommissioned a benzene-reducing process in 2023 and replaced it with a third-party method that has "periodically paused", allowing emissions to rise from 13 tonnes in 2022 to 17 tonnes in 2024, according to EA records, despite the regulator being aware of the issue since 2023. A March 2026 inspection found several permit breaches, and modelling ordered by the EA showed "significant" breaches of legally binding air quality standards, with one scenario exceeding the 24-hour benzene limit by 933%. Huntsman insists it remains "fully compliant" with its permit, while the EA says predicted concentrations stay below environmental standards but is still weighing further enforcement action alongside health agencies.