SEHSC Welcomes EPA-Granted Manufacturer-Requested Risk Evaluation of D4

WASHINGTON (October 7, 2020) – Members of the Silicones Environmental, Health and Safety Center (SEHSC), a sector group of the American Chemistry Council (ACC), today welcomed a U.S. Environmental Protection Agency (EPA) decision to grant the industry’s request for a risk evaluation of D4 under the Toxic Substances Control Act. SEHSC is planning to formally notify EPA of its desire that the Agency proceed with the risk evaluation and expects to submit the initial fee payment in a timely manner consistent with the Agency’s rules.

SEHSC’s request notably included a comprehensive and complete draft human health and environmental risk evaluation prepared in accordance with EPA guidance. This risk evaluation includes results from the rigorous D4 environmental monitoring program the silicones industry designed and executed in collaboration with EPA from 2014 to 2017. An independent, peer-reviewed risk assessment that incorporated the monitoring results concluded that D4 poses negligible risk to the environment.

“SEHSC has been steadfast in its support for the risk-based assessments of silicone substances, including D4,” said Karluss Thomas, Senior Director of SEHSC, ACC’s Chemical Products and Technology Division (CPTD). “Proceeding with EPA’s risk evaluation of D4 is further demonstration of that commitment and the industry’s confidence in the safety of D4 for human health and the environment. Based on SEHSC’s thorough risk evaluation submitted to EPA, the scientific evidence continues to confirm that no regulatory restrictions on D4 are warranted. SEHSC looks forward to a timely, transparent, and scientifically sound risk determination for D4 and stands ready to address any technical questions EPA may have as it conducts its D4 risk evaluation.”

Greater than 99 percent of D4 is used as an intermediate to make products that provide vital societal benefits from a variety of industries, including: transportation,  building and constructionhealth care, and electronics. As an intermediate, D4 enables a host of technologies including solar panels and wind turbines that help reduce carbon emissions and improve energy efficiencies.

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