Chemistry:β-Hexachlorocyclohexane

From HandWiki

β-Hexachlorocyclohexane
Beta-hexachlorocyclohexane.svg
Ball-and-stick model of the beta-hexachlorocyclohexane molecule
Names
Preferred IUPAC name
(1r,2r,3r,4r,5r,6r)-1,2,3,4,5,6-Hexachlorocyclohexane
Other names
β-HCH
β-Benzenehexachloride
β-BHC
Identifiers
3D model (JSmol)
1907338
ChEBI
ChEMBL
ChemSpider
EC Number
  • 206-271-3
KEGG
UNII
Properties
C6H6Cl6
Molar mass 290.83 g/mol
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
☑Y verify (what is ☑Y☒N ?)
Infobox references
Tracking categories (test):

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 since 1985.[1] As of 2009, the Stockholm Convention on Persistent Organic Pollutants classified α-hexachlorocyclohexane 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] β-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 β-BHC. This synonym still persists.

In March 2005, the Italian National Monitoring System on Chemical Residuals in Food of Animal Origin detected levels of the pesticide β-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. β-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

References

  1. 1.0 1.1 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. "[Beta-hexachlorocyclohexane contamination in dairy farms of the Sacco River Valley, Latium, Italy, 2005. A retrospective cohort study]" (in it). Epidemiol Prev 36 (5 Suppl 4): 34–43. 2012. PMID 23139187. 
  5. "Valle del Sacco: a poisoned land". 28 December 2012. http://www.valledelsacco.eu/valle-del-sacco-a-poisoned-land/. 

External links