C6Cl6

Hexachlorobenzene, with the chemical formula C6Cl6, is a chlorinated aromatic hydrocarbon. It is a colorless crystalline solid with a distinct odor, though it is often found as a powder. Historically, hexachlorobenzene was used as a pesticide, particularly as a seed dressing to protect against fungal diseases. It was also employed as a fungicide and a wood preservative.

The production of hexachlorobenzene typically involves the chlorination of benzene. Due to its persistent nature and potential for bioaccumulation, its use has been significantly restricted or banned in many countries. Hexachlorobenzene is considered a Persistent Organic Pollutant (POP) under the Stockholm Convention, an international treaty aimed at eliminating or restricting the production and use of POPs.

Exposure to hexachlorobenzene can occur through ingestion, inhalation, or skin contact. Health effects associated with exposure can include liver damage, thyroid problems, and skin conditions like chloracne. It is also considered a probable human carcinogen. Due to its persistence in the environment, it can remain in soil and water for extended periods, posing a long-term risk to ecosystems and human health. Research continues to monitor its environmental presence and potential long-term impacts.