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POST TIME: 20 September, 2015 00:00 00 AM
Tackling DDT�s long-term effects
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Radhika Singh

Tackling DDT’s long-term effects

A few weeks ago, India entered into an agreement with the UN to end the use of the insecticide DDT by 2020. DDT had been used in agriculture for decades until it was restricted in 1989, but 6,000 tonnes of DDT are still produced annually for the eradication of mosquitoes and other pests. This would be perfectly understandable, except for the simple fact that DDT has become ineffective — in the last decade, most insects have developed a resistance to it. The resulting instinct to simply use greater amounts of DDT or replace it with other harmful Persistent Organic Pollutants (POPs) has infused India’s soil, water and air with a concoction of noxious chemicals. Other insecticides and pesticides that are used specifically for agriculture further contaminate our environment. After it restricted DDT, the government began encouraging the use of other POPs that were potentially even more harmful, such as HCH (later banned in 1997), endosulfan (later banned in 2011) and then lindane (restricted in 2012). Rather than acknowledge that the makeup of all POPs render them intrinsically harmful, the government seems to be promoting different POPs in turn until each is found to have tangible toxic effects. Perhaps this is due to the fact that India is the second largest producer of pesticides in Asia and the fourth in the world. Samples of drinking water across India show high concentrations of HCHs, endosulfan isomers and DDT metabolites. Laws in India do permit some level of these substances in food and water, but these amounts are many times higher than those allowed in the West. DDT doses in food, for instance, are permitted to be seven times higher than doses in the European Union; lindane doses are allowed to be a 100 times higher and endosulfan doses 40 times higher (and 200 times higher for water). The air in Indian cities has also been recorded to contain the highest concentration of HCHs in the world.
The pervasive presence of DDT and other POPs is a consequence of their slow degradation. DDT-infused indoor insecticide spray used thirty years ago still lingers on the walls of homes. Crops that are grown in fields that were sprayed with DDT in the last decades show substantial traces of the insecticide. Unfortunately, the degradative products of some POPs are also highly toxic.

The writer is an environmentalist