Organochlorine insecticides made their appearance on the market in the 40s. The first use was made of them was in the fight against malaria, generalized commercial synthesis after the end of World War II.
This first generation of synthetic insecticides began with the DDT, which was extensively tested in the United States since 1942. Then it happened several products such as aldrin, chlordane, dieldrin, endrin, heptachlor, lindane, etc.
DDT (common name for the dichloro difeniltricloroetano) quickly gained popularity due to its high insecticidal activity, broad-spectrum, high and relatively low residual risk to warm-blooded animals (acute oral LD50: 250 mg / kg.). Besides its use as an agricultural insecticide was used as an insecticide domestic and environmental sanitation (control of mosquito vectors of malaria).
In Argentina, the use of DDT was banned in June 1974, but only for export products. Later, DDT was removed from the market but allowed the use of other chlorinated products for the domestic market.
DDT, and lindane gamexane are banned for use in veterinary medicine. However, there are human louse to contain them and are still sold in our pharmacies. About two years ago, is totally banned the use and sale of products containing heptachlor in the country.
This family of insecticides has had its pros and cons. Among the advantages are the excellent results that provide certain products but, on balance, these results are more important than the damage they cause to the environment and living organisms and could be summarized as follows:
This first generation of synthetic insecticides began with the DDT, which was extensively tested in the United States since 1942. Then it happened several products such as aldrin, chlordane, dieldrin, endrin, heptachlor, lindane, etc.
DDT (common name for the dichloro difeniltricloroetano) quickly gained popularity due to its high insecticidal activity, broad-spectrum, high and relatively low residual risk to warm-blooded animals (acute oral LD50: 250 mg / kg.). Besides its use as an agricultural insecticide was used as an insecticide domestic and environmental sanitation (control of mosquito vectors of malaria).
Resistance to organochlorine insecticides
Many of the major pests (spider mites, caterpillars capulleras, etc) soon showed a hereditary capacity to generate resistance to DDT and other organochlorine insecticides that succeeded him. This was produced by the transformations that the product in living organisms. Thus: a compound breaks down into antitoxin, produced by insects. This power is transmitted from generation to generation, resulting in immunity to DDT.Chemical stability of insecticides
Organochlorine insecticides have very high chemical stability and its molecules remain unchanged for a long time in the environment. Some bodies metabolize these compounds very slowly. Consequently, they accumulate and persist for long periods. They accumulate in the grass affecting the entire food chain, moving the animals. They accumulate in the fat of animals, where they are removed very slowly and even in milk fat when cows have grazed in areas treated with these insecticides.The aggression of agrochemicals
The whole mechanism of "aggression" to the environment led the United States cancel the use of DDT in 1973. Nowadays, most organochlorine pesticides are banned in many countries worldwide.In Argentina, the use of DDT was banned in June 1974, but only for export products. Later, DDT was removed from the market but allowed the use of other chlorinated products for the domestic market.
DDT, and lindane gamexane are banned for use in veterinary medicine. However, there are human louse to contain them and are still sold in our pharmacies. About two years ago, is totally banned the use and sale of products containing heptachlor in the country.
Action Form
They act by contact and ingestion and some of them (such as lindane and chlordane) have fumigant action. In the body, do not change the conduction of stimuli between neurons as they organophosphate nerve endings acting on enhancing the release of neurotransmitters. Thus, effects of excitement, shock and subsequent death.This family of insecticides has had its pros and cons. Among the advantages are the excellent results that provide certain products but, on balance, these results are more important than the damage they cause to the environment and living organisms and could be summarized as follows:
- High residual
- Failure to adhere to the ground and the ability to filter webs
- Assimilation in human and animal fatty tissues
- Causal liver and lung disorders
- Irreversible damage in the case of poisoning
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