Indian researchers, for the first time, have found that endosulfan, an organochlorine pesticide, causes DNA damages in animals. They have revealed that mice and rats exposed to endosulfan suffer from DNA damage and genomic instability, and impaired DNA damage response.
The results were published on 4 August 2016 in the journal, Carcinogenesis.
Key highlights of the study
• A team of researchers led by Professor Sathees Raghavan from the Department of Biochemistry, IISc, Bengaluru revealed that endosulfan breaks in DNA strands and disturbs the damage response mechanism found in cells, which leads to compromised DNA strand repair.
• Mice and rats exposed to endosulfan generated reactive oxygen species, a potent DNA damaging agent.
• The reactive oxygen species, in turn, caused DNA damage in the form of breaks in DNA strands.
• The broken DNA strands generally tend to repair themselves by rejoining. However, endosulfan treatment was found to cause extensive processing of broken DNA, which leads to increased and long deletion in the strands.
• Endosulfan also increased the damage by promoting erroneous repair of the broken DNA strands. Erroneous repair will lead to undesirable genome level changes leading to genomic instability, which may cause cancer and genetic abnormalities.
• Five animals per group were studied and the experiment was repeated many times.
• Three different concentrations of endosulfan were tested on animals and four doses of each concentration were given at 24 hours interval.
• Even the highest dosage of 3 mg per kg of body weight used in the experiments is well below the lethal concentration of 12 mg/kg body weight.
• Lungs and testes of the animals were used for the study. These two organs show very proficient DNA repair mechanism.
What is endosulfan?
• Endosulfan is an off-patent organochlorine insecticide.
• Endosulfan sulfate is a product of oxidation containing one extra O atom attached to the S atom.
• Endosulfan became a highly controversial agrichemical due to its acute toxicity, potential for bioaccumulation, and role as an endocrine disruptor.
• Because of its threats to human health and the environment, a global ban on the manufacture and use of endosulfan was negotiated under the Stockholm Convention in April 2011.
• The ban took effect in mid-2012, with certain uses exempted for five additional years.
• More than 80 countries, including the European Union, Australia, the United States of America had already banned it or announced phase-outs by the time the Stockholm Convention ban was agreed upon.
• It is still used extensively in India, China, and a few other countries.
• It is produced by Makhteshim Agan and several manufacturers in India and China.
Now get latest Current Affairs on mobile, Download # 1 Current Affairs App