beta-Hexachlorocyclohexane

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β-hexachlorocyclohexane
Beta-hexachlorocyclohexane.svg
Identifiers
CAS number 319-85-7 YesY
ChemSpider 10468512 YesY
ChEBI CHEBI:28428 YesY
ChEMBL CHEMBL389022 YesY
Jmol-3D images Image 1
Properties
Molecular formula C6H6Cl6
Molar mass 290.83 g/mol
Except where noted otherwise, data are given for materials in their standard state (at 25 °C (77 °F), 100 kPa)
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Infobox references

β-hexachlorocyclohexane (β-HCH) is an organochloride which is one of the isomers of hexachlorocyclohexane (HCH).[1] It is a byproduct of the production of the insecticide lindane (γ-HCH). It is typically constitutes 5-14% of technical grade lindane,[2] though it has not been produced or used in the United States for more than 20 years, i.e. since 1985.[1] As of 2009, the Stockholm Convention on Persistent Organic Pollutants classified (α-HCH) and (β-HCH) as Persistent organic pollutants (POPs), due to the chemical's ability to persist in the environment, bioaccumulative, biomagnifying, and long-range transport capacity.

This pesticide was widely used during the 1960s and 1970s, particularly on cotton plants. Although banned as a pesticide more than 30 years ago, traces of beta-HCH can still be found in water and soil. Animal studies show that organochlorine pesticides, including beta-HCH, are neurotoxic, cause oxidative stress, and damage the brain's dopaminergic system. Human studies show that exposure to beta-HCH is linked to Parkinson's and Alzheimer's disease.[3] Beta-HCH was present in elevated levels in some patients as recently as 2009. It was manufactured by exhausting chlorination of benzene and for this reason was called erroneously beta-BHC. This synnonym still persists.

In March 2005, the Italian National Monitoring System on Chemical Residuals in Food of Animal Origin detected levels of the pesticide beta-hexachlorocyclohexane (ß-HCH) that were 20 times higher than the legal limit of 0.003 mg/kg in bulk milk from a dairy farm in the Sacco River valley. ß-HCH, a lindane isomer and possible human carcinogen, was subsequently found in milk from several neighboring farms. A study was therefore undertaken to evaluate the extent and risk factors for contamination. [4] [5]

See also[edit]

References[edit]

  1. ^ a b Toxicological Profile for Alpha-, Beta-, Gamma-, and Delta-Hexachlorocyclohexane, U.S. Department of Health and Human Services, Agency for Toxic Substances and Disease Registry, August 2005
  2. ^ beta-hexachlorocyclohexane (Beta HCH), Draft Risk Profile, May 2007
  3. ^ Medscape Medical News, Pesticide Exposure Linked to Parkinson's, Alzheimer's Disease, July 2009
  4. ^ [1], Beta-hexachlorocyclohexane contamination in dairy farms of the Sacco River Valley, Latium, Italy, 2005. A retrospective cohort study
  5. ^ [2], Valle del Sacco: a poisoned land

External links[edit]