beta-hexachlorocyclohexane beta-hexachlorocyclohexane β-hexachlorocyclohexane (β-hch) is an organochloride which is one of the isomers of hexachlorocyclohexane (hch). it is a byproduct of the production of the insecticide lindane (γ-hch). it is typically constitutes 5–14% of technical-grade lindane, though it has not been produced or used in the united states since 1985. 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. β-hexachlorocyclohexane names preferred iupac name (1r,2r,3r,4r,5r,6r)-1,2,3,4,5,6-hexachlorocyclohexane other names β-hchβ-benzenehexachlorideβ-bhc identifiers cas number 319-85-7 y 3d model (jsmol) interactive image beilstein reference 1907338 chebi chebi:28428 y chembl chembl389022 y chemspider 10468512 y echa infocard 100.005.703 ec number 206-271-3 kegg c06988 unii ym80odm9pd y comptox dashboard (epa) dtxsid7020685 inchi inchi=1s/c6h6cl6/c7-1-2(8)4(10)6(12)5(11)3(1)9/h1-6h/t1-,2-,3+,4+,5-,6- ykey: jlyxxmfpniawkq-cdrysyessa-n yinchi=1/c6h6cl6/c7-1-2(8)4(10)6(12)5(11)3(1)9/h1-6h/t1-,2-,3+,4+,5-,6-key: jlyxxmfpniawkq-cdrysyesbr smiles cl1(cl)(cl)(cl)(cl)1cl properties chemical formula c6h6cl6 molar mass 290.83 g/mol except where otherwise noted, data are given for materials in their standard state (at 25 °c , 100 kpa). y verify (what is yn ?) infobox references 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. 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.