Beta-hexachlorocyclohexane

Beta-hexachlorocyclohexane (β-HCH) is an organochloride compound that is classified as a persistent organic pollutant (POP). It is an isomer of hexachlorocyclohexane (HCH), a chemical that was widely used as an insecticide and pesticide until it was banned due to its toxicity and persistence in the environment.

Chemical Structure and Properties

Chemical structure of beta-hexachlorocyclohexane

β-HCH has a molecular formula of C₆H₆Cl₆. It is a white, crystalline solid with a slight, characteristic odor. It is virtually insoluble in water but highly soluble in organic solvents, fats, and oils.

Production and Use

β-HCH is not produced intentionally but is a byproduct in the production of the insecticide lindane (γ-HCH). The use of lindane has been severely restricted due to its toxicity and persistence in the environment. However, large amounts of β-HCH were produced as waste and have contaminated the environment.

Health Effects

Exposure to β-HCH can occur through ingestion, inhalation, or skin contact. It is a neurotoxin and can cause a variety of symptoms including headache, dizziness, nausea, and seizures. Long-term exposure can lead to liver damage and possibly cancer. β-HCH is also an endocrine disruptor, meaning it can interfere with the body's hormonal system.

Environmental Impact

β-HCH is highly persistent in the environment and can remain in soil and water for many years. It can bioaccumulate in the food chain, leading to high concentrations in predatory animals. It is also capable of long-range transport and can be found in regions far from where it was produced or used.

Regulation

Due to its toxicity and persistence, β-HCH is listed as a POP under the Stockholm Convention. This international treaty aims to eliminate or restrict the production and use of persistent organic pollutants.

See Also

• Persistent organic pollutant
• Hexachlorocyclohexane
• Lindane
• Endocrine disruptor
• Stockholm Convention