Why endosulfan, all insecticides are poison

The pathetic plight of the people of Kasaragod in Kerala, in the wake of the endosulfan fiasco, brings into focus an issue which is a ramification of the green revolution. Whatever the technical grounds for its acceptance or rejection, the fear engulfing the minds of people can be removed only if a full-fledged assurance is given on the complete ban on the pesticide. 

Insecticides which kill the worms that destroy crops are seldom selective in their action. Most of them affect other life forms though at a higher dose. An insecticide is basically a poison. By its very mode of action, a poison is detrimental to all life forms; only the dosage to manifest the adverse effects varies.

According to Paracelsus, Swiss physician of the Rrenaissance period, “all things are poison and nothing is without poison. It is the dose that makes a thing not a poison.” Most of the body sprays, phenolic soaps and lotions and even naphthalene balls are known to be carcinogenic. However, we are able to tolerate a low dose of exposure in daily life.

Several external agents are continuously destroying the vital molecules in the body of living forms. But in most cases, especially in higher life forms, these are restored through a repair mechanism. When the repair mechanism is weak or not able to cope with them, different diseases develop. 

In Kasaragod, endosulfan was aerially sprayed from a helicopter. Though effective in uniform dispersal, this procedure is the root cause of the present malady. The droplets of the insecticide would have traversed several kilometres beyond the boundary of the plantation. This would naturally adversely affect other life forms, including humans. Thus, aerial spraying has to be abandoned and spraying with hand machines is more desirable even though it is labour intensive. Spraying has to be carried out after checking with the weather department about imminent rain or cyclone. Both natural events would diminish the effect of the insecticide on the plantation and also carry the poison to undesired locations.

The spray is pointed at insects adhering to the leaves and flowers. But a large quantity of it may fall on other regions and the ground. This may be carried by wind for several days to far-off places. 

Wake-up call

The story of DDT was the wake-up call. Traces of this compound were noticed even among the penguins living in the South Pole, where no spray of DDT was ever carried out. In other words, the spray from the habited land mass has crossed the continental borders and reached almost the entire globe. It has also crossed the placental barrier and new babies are born with DDT contamination. Even the mother's milk contains a small dosage of DDT. This is the fate of a chemical thought to be marvellous in controlling insects and to have contributed immensely to the agricultural revolution of the 1950s and 1960s. The inventor also won the Nobel Prize for contribution thought to be the wonder chemical in the initial years.The banning of DDT was spearheaded by a U.S. researcher who found that this chemical had adversely impacted the life of certain water birds.

Another mode of transport is by water and this may find access to the nearby river. This contamination will have a deleterious effect on marine life. Some of the marine life may accumulate certain chemicals, which may enter the food chain of land animals at a higher dose detrimental to health. Further, bio-magnification to a lethal dose may take place in the higher life forms. The Minamata disease that occurred in Japan is a standing example of such maladies. In this case, marine organisms bio-accumulated mercury that causes nervous diseases. Thus continuous analysis of soil, water and air samples has to be carried out around the area of insecticide spray to understand the imminent impact and retain it within tolerable limits.

Precautions

Even after a ban on endosulfan, it is necessary to resort to other forms of insecticides. Several constraints and precautions have to be exercised in the usage.

• Spraying is a technically skilled job and has to be carried out manually by skilled personnel on the ground. These personnel have to be certified by the Agricultural department.

• They shall wear special protective clothing and respirators. A mere mask is not enough.After the spray, the clothing and respirator have to be cleaned up and stored after packing on the farm itself. It is even desirable to bury the cloth in the plantation itself.

• The personnel have to be fully decontaminated (which includes bathing) before they go home. Children and pregnant women at home are likely to be more susceptible to these poisons.

• Simultaneous scientific investigations on the flora and fauna around the plantation should be carried out throughout the year in addition to the analysis of air, water and soil samples.

• Contamination may spread to waterbodies around the plantation and affect marine life. Land erosion and leaching in the sprayed area have to be arrested with appropriate action.

• If any adverse effect is noticed, the insecticide has to be discontinued. It is not necessary to wait until a human catastrophe of unmanageable magnitude surfaces to rouse the conscience of society. 

Not only endosulfan, but most other insecticides are poison to all forms of life.

Courtesy : The Hindu (Dr. S. Rajendran Pillai)