Hexachlorobutadiene (HCBD)

Hexachlorobutadiene (HCBD) is a synthetic halogenated aliphatic compound that contains chlorinated hydrocarbons. Its widespread environmental presence could be attributed to process of chemical production and emission from industrial activities and waste treatments where HCBD is unintentionally produced. Considering its toxicity, persistence, bioaccumulation, and long-range transport abilities, Stockholm Convention listed HCBD in 2015 as POPs under Annex A and in 2017; it was further listed in Annex C for unintentional formation and emission control. This chapter summarizes HCBD’s main characteristics, formation pathways and sources, occurrence in various environmental compartments, and various exposure risks and related ecological effects. Many animal studies have proven that this toxic compound damages the liver and kidney, raising cancer concerns. Aquatic organisms can bioaccumulate HCBD, affecting higher trophic level creatures. Controlling unintentional emissions by using Best Available Techniques (BAT) and implementing remediation measures by implementing Best Environmental Practices (BEP) reduces HCBD contamination. Understanding hexachlorobutadiene (HCBD) behavior, fate, and toxicology promotes environmental stewardship and protects people and ecosystems. Research attention is needed in studying the environmental risks associated with contamination of HCBD with other environmental pollutants.