Application of Biodegradable Pesticides in India
261
to bring about such ill effects can be produced in bird and fish tissues by even
a single environmental exposure.
Aldrin, BHC, and heptachlor are very effective soil insecticides because of
their relatively high vapor pressure. Toxaphene was once widely used to control
external parasites on cattle, sheep, and other domestic animals, the advantage
being its ready excretion and hence negligible tissue storage. The use of toxaphene for veterinary purposes is, however, now banned in the United States.
Combination products of toxaphene and DDT have also been phased out in India.
In many countries, the use of DDT has also been banned in view of its residual
effects and suspected carcinogenic potential based on experiments in mice. In
India, it is still permitted along with BHC in the campaign against malaria and
other insect vector-borne diseases.
Keeping in mind the vast area to be covered in India and the compelling
necessity to control malaria, efforts have been made to meet the country's requirements by indigenous production. The current production is around 5000
metric tons, although the installed capacity is 14,000 metric tons. DDT-toxaphene
was also sprayed until recently in the form of Heliotox for the control of cotton
pests. Residues of DDT were analyzed in the seed and lint of cotton and found
to be below the tolerance level of 7 ppm after 4 days. However, when DDT
was applied combined with toxaphene the residues were always higher than when
DDT was applied alone. The rate of disappearance of DDT from sprays of
DDT-toxaphene was much slower than that of DDT from DDT sprays (Anonymous, 1977).
The mechanism of bio- or physicochemical degradation from soil and plants
is poorly understood. The need for intensive research in this area must be emphasized. Considering its magnitude, the problem of persistence of residues in
plants and in fat deposits of man and animals has not yet attracted the attention
of many scientists in India.
The present overview of the situation is prompted by a desire to identify
areas of research out of which remedial action can, it is to be hoped, be devised
to protect plants, soil, animals, and above all humans from the potential hazards
of pesticides and their derivatives and degradation products (Anonymous, 1979b).
10.2. THE PESTICIDE INDUSTRY IN INDIA
The manufacture of pesticides began in India in 1952 with the construction
of a plant for producing BHC. This was followed by a plant for DDT. Among
the South Asian and African countries, excluding Japan, India is the largest
manufacturer of basic pesticidal chemicals. In all, 122 pesticides have been
261
to bring about such ill effects can be produced in bird and fish tissues by even
a single environmental exposure.
Aldrin, BHC, and heptachlor are very effective soil insecticides because of
their relatively high vapor pressure. Toxaphene was once widely used to control
external parasites on cattle, sheep, and other domestic animals, the advantage
being its ready excretion and hence negligible tissue storage. The use of toxaphene for veterinary purposes is, however, now banned in the United States.
Combination products of toxaphene and DDT have also been phased out in India.
In many countries, the use of DDT has also been banned in view of its residual
effects and suspected carcinogenic potential based on experiments in mice. In
India, it is still permitted along with BHC in the campaign against malaria and
other insect vector-borne diseases.
Keeping in mind the vast area to be covered in India and the compelling
necessity to control malaria, efforts have been made to meet the country's requirements by indigenous production. The current production is around 5000
metric tons, although the installed capacity is 14,000 metric tons. DDT-toxaphene
was also sprayed until recently in the form of Heliotox for the control of cotton
pests. Residues of DDT were analyzed in the seed and lint of cotton and found
to be below the tolerance level of 7 ppm after 4 days. However, when DDT
was applied combined with toxaphene the residues were always higher than when
DDT was applied alone. The rate of disappearance of DDT from sprays of
DDT-toxaphene was much slower than that of DDT from DDT sprays (Anonymous, 1977).
The mechanism of bio- or physicochemical degradation from soil and plants
is poorly understood. The need for intensive research in this area must be emphasized. Considering its magnitude, the problem of persistence of residues in
plants and in fat deposits of man and animals has not yet attracted the attention
of many scientists in India.
The present overview of the situation is prompted by a desire to identify
areas of research out of which remedial action can, it is to be hoped, be devised
to protect plants, soil, animals, and above all humans from the potential hazards
of pesticides and their derivatives and degradation products (Anonymous, 1979b).
10.2. THE PESTICIDE INDUSTRY IN INDIA
The manufacture of pesticides began in India in 1952 with the construction
of a plant for producing BHC. This was followed by a plant for DDT. Among
the South Asian and African countries, excluding Japan, India is the largest
manufacturer of basic pesticidal chemicals. In all, 122 pesticides have been