agra,ahmedabad,ajmer,akola,aligarh,ambala,amravati,amritsar,aurangabad,ayodhya,bangalore,bareilly,bathinda,bhagalpur,bhilai,bhiwani,bhopal,bhubaneswar,bikaner,bilaspur,bokaro,chandigarh,chennai,coimbatore,cuttack,dehradun,delhi ncr,dhanbad,dibrugarh,durgapur,faridabad,ferozpur,gandhinagar,gaya,ghaziabad,goa,gorakhpur,greater noida,gurugram,guwahati,gwalior,haldwani,haridwar,hisar,hyderabad,indore,jabalpur,jaipur,jalandhar,jammu,jamshedpur,jhansi,jodhpur,jorhat,kaithal,kanpur,karimnagar,karnal,kashipur,khammam,kharagpur,kochi,kolhapur,kolkata,kota,kottayam,kozhikode,kurnool,kurukshetra,latur,lucknow,ludhiana,madurai,mangaluru,mathura,meerut,moradabad,mumbai,muzaffarpur,mysore,nagpur,nanded,narnaul,nashik,nellore,noida,palwal,panchkula,panipat,pathankot,patiala,patna,prayagraj,puducherry,pune,raipur,rajahmundry,ranchi,rewa,rewari,rohtak,rudrapur,saharanpur,salem,secunderabad,silchar,siliguri,sirsa,solapur,sri-ganganagar,srinagar,surat,thrissur,tinsukia,tiruchirapalli,tirupati,trivandrum,udaipur,udhampur,ujjain,vadodara,vapi,varanasi,vellore,vijayawada,visakhapatnam,warangal,yamuna-nagar

Benzene Hexachloride

BHC is one of various stereoisomers of 1,2,3,4,5,6-hexachlorocyclohexane. It is formed by the light-induced addition of chlorine to benzene. One of these isomers is the insecticide lindane, also known as Gammexane.

  • The insecticidal properties of benzene hexachloride were identified in 1944 with the -isomer.
  • -isomer is 1,000 times more toxic than any of the other diastereomers formed in the reaction.
  • The orientations of the chlorine atoms with respect to the carbon ring are the structural variations between these individuals.
  • When chlorine is added to benzene, it produces a mixture of several stereoisomers of 1,2,3,4,5,6-hexachlorocyclohexane.
  • The -isomer (20–25 percent of this mixture), is more soluble in certain solvents than the other isomers and can thus be separated from them.
  • Benzene hexachloride, which is more volatile as compared to DDT, kills insects faster but for a shorter timespan.

Benzene Hexachloride Preparation

  • In the presence of sunlight and in the absence of oxygen and substitution catalysts, chlorine combines with benzene to form hexachlorocyclohexane.
  • Photochlorination can be used to create lindane from benzene and chlorine.
  • The resulting product, benzene hexachloride, contains isomers, of which only the -isomer is desired.
  • The gamma-isomer is obtained by treating the reaction mixture with methanol or acetic acid, which dissolves only the alpha and beta isomers easily.

Properties of Benzene Hexachloride

Benzene hexachloride


Molar mass/molecular mass

290.814 g/mol


1.89 at 66°F

Boiling point


Melting point 


Harmful effects of Benzene Hexachloride

  • Lindane has been found to build up in the food chain.
  • Animals and humans consume foods grown in soils contaminated with lindane.
  • Fish and other marine life are exposed to waters contaminated with lindane.
  • Exposure to high levels of lindane in fish and mammals can result in acute poisoning and dysfunction of the nervous system.
  • Chronic exposure may have a negative effect on liver functions of humans.
  • Lindane is no longer permitted to be used as smoke fumigators inside closed spaces, and its use as an insecticide is prohibited in many countries.
  • Although, the use of BHC as topical lice-fighting ointments is permitted.

Adverse effects

  • A wide range of adverse reactions to lindane pharmaceuticals have been reported, such as skin irritation,seizures and, in rare cases, death.
  • Burning sensations, dryness, itching, and rash are the most common side effects.
  • While serious side effects are uncommon and almost always the result of misuse, adverse reactions have occurred when used properly.
  • As a result, the FDA requires a so-called black box warning on lindane products, which explains the risks of lindane products and how to use them properly.
  • The black box warning emphasises that lindane should not be used on premature infants or individuals with known uncontrolled seizure disorders
  • It should be used with caution in infants, children, the elderly, and people with other skin conditions (e.g., psoriasis, dermatitis), as they may be at risk of serious neurotoxicity.


  • The gamma isomer of hexachlorocyclohexane ("-HCH") is lindane.
  • Aside from lindane pollution, there are some concerns about the other isomers of HCH, i.e. alpha-HCH and beta-HCH, which are significantly more toxic than lindane, lack its insecticidal properties, and are byproducts of lindane production.
  • In the 1940s and 1950s, lindane producers piled these isomers in open heaps, contaminating the ground and water.
  • Since then, the International HCH and Pesticide Forum has been formed to bring experts together to address the containment of these sites.
  • Modern lindane manufacturing practises include the treatment and conversion of waste isomers to less toxic industrial chemicals. This process is known as "cracking."
  • Today, only a few production plants remain operational around the world to accommodate lindane's public-health applications and declining agricultural needs.
  • Lindane has not been produced in the United States since the mid-1970s, but it is still imported.
Talk to our expert
Resend OTP Timer =
By submitting up, I agree to receive all the Whatsapp communication on my registered number and Aakash terms and conditions and privacy policy