To preserve a variety of food and their products, various pesticides or insecticides are used. We are very aware of insecticides like DDT, Aldrin, and BHC, etc. In Assam DDT is still used by the Health Department to control mosquitoes even though the use of DDT was banned outside India many years ago. Besides these insecticides we would like to mention another very important organochlorine insecticide which is called endosulfan.

 

Though the use of endosulfan had already been banned in some developed countries, it is still used in India and China. Endosulfan has come into the limelight because it is highly toxic besides being a major pollutant of the environment.

Endosulfan became a highly controversial agrichemical due to its acute toxicity and role as an endocrine disruptor. Endosulfan toxicity is not only a threat to human health but also to the environment as a whole. A global ban on the manufacture and use of endosulfan was negotiated under the Stockholm Convention in April 2011 which will come into effect in mid 2012. Though the use of endosulfan had already been banned in some developed countries, it is still used in India and China. Endosulfan has come into the limelight because it is highly toxic besides being a major pollutant of the environment.

Endosulfan is used in agricultural fields from which it flows to beel, river through rain water and it not only damages the aquatic plants but also aquatic animals like fish, etc. When we unknowingly consume infected fish, it immediately disrupts the metabolic activities of our body besides the endocrine system.

Endosulfan is an organochlorine insecticide which is at the centre of a world wide controversy because of its acute toxicity. It is generally used to control insect pests including whiteflys, aphids, leafhoppers, Colorado potato beetles and cabbage worms. It is also moderately toxic to honeybees. Endosulfan was developed in 1950 for the first time but in USA it was banned in 2000 and after 11 years i.e.2011, the Supreme Court of India has banned the manufacture, sale and use of the toxic pesticide endosulfan in India. Though the banning of endosulfan was announced, its production and use is still going on. According to the World Health Organization the production of endosulfan world wide was estimated at 9000 metric tonnes in early 1980s and it increased to 12,800 metric tonnes per year in 1900.

 

In Kerala, endosulfan spraying resulted in abnormalities in local children in 2001. In 2006, in Kerala, compensation of rupees 50,000 was paid to the kin of each of the 135 people who were identified as having died as a result of endosulfan use.

Endosulfan is one of the most toxic pesticides in the market today, responsible for many fatal pesticide poisoning incidents around the world. It can act as an endocrine disruptor, causing reproductive and developmental damage both in animals and humans. It is still debated whether endosulfan can cause cancer. Endocrine glands secrete hormones and each hormone has a very important role in growth and development which is interrupted by endosulfan. Numerous in vitro studies have documented its potential to disrupt hormones especially among males.

In India researchers have studied various children from villages in Kerala where endosulfan exposure delays sexual maturity especially among boys. The exposed boys had a high level of endosulfan in their bodies, lower levels of testosterone and delays sexual maturity.

A study of the public health department of California in 2007 found that women who lived near farm fields sprayed with endosulfan during the first eight weeks of pregnancy are several times more likely to give birth to children with autism. There is no epidemiological studies linking exposure to endosulfan especially to cancer in human but in vitro studies have shown that it can promote proliferation of human breast cancer cells.

As endosulfan is used in agricultural fields, it has an indirect role in interrupting the environment. A 2008 report by the National Park Service found that endosulfan commonly contaminates air, water, plants and fish of national parks in the U.S. Endosulfan has also been detected in the dust of the Sahara Desert.

India is the largest user of endosulfan in the world. There are three companies such as Excel crop care, Hindustan Insecticides Ltd. and Coromandal Fertilizer which are producing 4,500 tonnes of endosulfan annually for domestic use besides an additional 4000 tonnes for export.

In Kerala, endosulfan spraying resulted in abnormalities in local children in 2001. In 2006, in Kerala, compensation of rupees 50,000 was paid to the kin of each of the 135 people who were identified as having died as a result of endosulfan use. Chief Minister V.S.Achuthanandan extended free treatment to the victims and requested Prime Minister Dr. Monmohan Singh to ban the use of endosulfan in India. After an intense support from various states of India finally the Supreme Court passed an interim order on May 13th, 2011 and banned the production, distribution and use of endosulfan in India. If the use of endosulfan is completely banned as per the order given by the Supreme Court in the real sense, all living organisms as well as environment will be saved.

Recently, in the last week of June, 2011 at the Rotterdam Convention, India maintained silence at the beginning on listing of endosulfan. However, the Convention agreed in principle to list endosulfan but Cuba would not agree to the listing unless the decision included need for technical and financial assistance. At the end of the Conference it was decided to list endosulfan under annexure III and India also supported this decision.

Dr. Jagadindra Raychoudhury

The author is Associate Professor (Department of Zoology) in B. Borooah College, Guwahati