HCBD (Hexachlorobutadiene)

HCBD (CAS 87-68-3) is a chlorinated compound restricted under TSCA Section 6(h). Used as a solvent, heat transfer fluid, and chemical intermediate. Manufacturing and processing are banned except as a byproduct at or below 1% by weight. Also regulated under EU POPs and the Stockholm Convention.

40 CFR § 751.413; EPA Final Rule (January 2021).

HCBD has the most straightforward restriction: ban on manufacturing/processing with a 1% byproduct exception. Screen chemical inventories for CAS 87-68-3 and confirm no intentional use.

A chlorinated solvents manufacturer produces HCBD as an unintentional byproduct at 0.5%, within the permitted exception.