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Gross violation

Gross violation Serious violations of environmental norms by pesticide manufacturers came to our notice through this shocking account by researchers from the department of zoology, Delhi University. They visited Chinhat Industrial Area near Lucknow and found stark evidence of toxic waste containing residues of hexachlorocyclohexane (HCH) being disposed of by the units through a drain and also at a dump some distance away. The researchers found high levels of HCH in various soil and water samples they tested.

This kind of research is a rarity. Although we keep hearing about waste from pesticide industry contaminating the environment, hard empirical data and specific case studies are hard to come by. How did this study come about? "We have been working, for a long time, on methods to decontaminate HCH waste and wanted to test them at an actual site,' informs Rup Lal, professor at the Molecular Biology Laboratory, who headed the team of researchers. "We knew of the industries that manufactured HCH and decided to visit them. Although we expected to find a dump, what we did not expect was dumping happening on such a large-scale on government land,' Lal adds. One thing led to another and Lal's team unearthed a deadly secret.

Research related to pesticides is mostly limited to measuring their levels in various kinds of samples (such as of water and soil), including farm produce. But this research is different. "We have gone to the source of HCH contamination and learnt how it actually happens,' says Lal. He says his team will be on the job for the next few years. But this time to try and decontaminate the affected area.

This study exposes what is horribly wrong in our regulation of pesticides and polluting industries. As Lal puts it, "Manufacturing one tonne of the pesticide lindane generates nine tonnes of highly toxic and persistent waste.' It's about time we learn where all that waste is going. Their account follows:
Human life seems cheap to the Indian pesticide industry. Why else would the manufacturers of toxic chemicals adopt a highly apathetic attitude as they set all environmental rules and norms aside? Even those who profess interest in safeguarding the environment remain largely ignorant of how grave a problem pollution is.

We visited industrial units in Chinhat, Lucknow in October 2004 which manufacture hexachlorocyclohexane (hch), a pesticide used extensively and indiscriminately in agriculture and against mosquitoes in health programmes for over 50 years now. This has caused widespread contamination of our food commodities and the environment. The problem was highlighted in a leading newspaper last year and also in a report published by the Centre for Science and Environment, New Delhi, which found mineral water and even soft drinks contaminated with the chemical.

The pesticide is produced by adding chlorine to benzene in the presence of ultraviolet light. The reaction produces a mixture of four isomers (which are variants with same chemical constitution but different physical and/or chemical properties) called alpha (a)-, beta (b)-, gamma (g)- and delta (d)-hch in the ratio 70, 12, 10 and 8 per cent respectively. Among these, only g-hch, or lindane, has the insecticidal property but its separation from other isomers requires several steps to be carried out. Thus, for purely economical reasons, two forms of hch have been extensively used in India: lindane and technical hch, which is a mixture of the four isomers.

But in 1997, a partial ban on lindane restricted its use to 500 tonnes annually. After lindane is extracted, the other isomers are treated as waste that, albeit toxic, is dumped in the open. Also, chemical industries in India continue to make technical hch for exports and this is also sometimes sold to farmers.

What we face now are two types of hch contamination: (1) low levels of contamination of soil system and (2) high level of contamination due to the disposal of a-, b-and d-hch at the production sites. The gradual leaching out of toxic chemicals from disposal sites are proving hazardous for people living in the vicinity.

Highly toxic
All the four hch isomers are resistant to metabolic and microbial degradation, and so pose a serious problem of environmental contamination. The compact spatial structure of b

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