Insecticide poisoning chlorinated hydrocarbons

TABLE 4-2. Signs and symptoms of insecticide poisoning Chlorinated hydrocarbon pesticides Acute Chronic... 

Muller had several clues to guide his search. First, he knew from Henri Martin s mothproofing work that a chlorinated hydrocarbon worked as a gastric moth poison. Second, his early experiments showed him that compounds with the group CH2C1 had some insecticidal effect. Third, a 1934 article in the Journal of the Chemical Society of London described the preparation of diphenyltrichloroethane, which Muller found to be somewhat poi-... 

Paul Hermann Muller received a degree in chemistry and worked for the J. R. Geigy Corporation, which later became part of Novartis (McGrayne 2001). Geigy specialized in dyestuffs for woolens. Chemists at the company discovered a chlorinated hydrocarbon compound that protected woolens from clothes moths, but it was a stomach poison. Geigy then searched for other insecticides that killed other pests. Natural insecticides made from plants include pyrethrum from chrysanthemum, rotenone from a tropical... 

The chlorinated hydrocarbons were among the first synthetic insecticide compounds to be used but have fallen into disfavor because of their persistence in the environment. Typical examples of chlorinated hydrocarbon insecticides are DDT, lindane, and to-xaphene. The toxicity of these compounds in small animals is characterized by severe CNS effects, including ataxia and convulsions. Small animals usually get poisoned by being accidentally sprayed or by... 

The pesticides most frequently responsible for equine poisonings are the organophosphate, carbamate, and chlorinated hydrocarbon insecticides. Both the organo-phosphates and the carbamates are acetylcholinesterase inhibitors and present clinical pictures similar to those seen in food-producing animals. Affected horses salivate and sweat profusely and have muscle incoordination and ataxia. The chlorinated hydrocarbons are strong CNS stimulants affected horses become hyperalert, then excited, and, in severe cases, develop convulsions. In almost all instances, the mode of horses being exposed to pesticides is topical. 

The greatest danger from the use of DDT over wide areas arises if water is contaminated. Damage to many forms of life may also occur when aquatic pests are controlled by chlorinated hydrocarbons. This is due to several causes. First, fish are particularly susceptible to DDT poisoning, so that fish deaths due to direct poisoning may occur immediately or soon after the insecticide has been applied. They may extract DDT, present in a low concentration, from the immense amount of water, which is passed through the gills for purposes of respiration. Second, insects and other invertebrates, which are the main food of some fish, may be exterminated, so the fish are starved. Third, the invertebrates may take up amounts of DDT, which are not immediately lethal when fish eats these poisoned animals, the DDT may be retained in the bodies of the fish, which over a period obtain a toxic dose. 

Lotti M, Becker CE, Aminoff MJ, et al Occupational exposure to the cotton defoliants DEF and Merphos. J Occup Med 25 517-522, 1983 Markowitz SB Poisoning of an urban family due to misapplication of household orga-nophosphate and carbamate pesticides. Clin Toxicol 30 295-303,1992 Mayersdorf A, Israeli R, Beer-Sheva I Toxic effects of chlorinated hydrocarbon insecticides on the human electroencephalogram. Arch Environ Health 28 159-163,... 

Gupta PC Neurotoxicity of chronic chlorinated hydrocarbon insecticide poisoning— a clinical and electroencephalographic study in man. Indian J Med Res 63 601-606, 1975... 

The poisonous effect of arsenic has been known since ancient times and its application against insects was recommended as early as the seventeenth century in a book by John Worlidge (Munro, 1946). The use of various inorganic preparations for plant protection increased to several hundred million tons per year by the 1940s, but since then they have been replaced to a considerable extent by chlorinated hydrocarbon insecticides. 

The mode of action of endrin is unknown. The symptoms of poisoning, as for other insecticides of the diene type, are indicative of neurotoxic action. The histopathological pattern of poisoning is the same as that of the other chlorinated hydrocarbon insecticides. 

Neurological Effects. A major incident of occupationally-related illness associated with a pesticide involved Kepone. Kepone is a chlorinated hydrocarbon insecticide used domestically as an ant and roach poison. In 1975, after workers at a plant... 

The organophosphate insecticides, when introduced, about 1945, made a large and welcome addition to what was available. Because a fuller account is given in Section 13.3, it need be said here only that they are nerve poisons which initially act in a quite different way from the pyrethroids and chlorinated hydrocarbons, for they are inhibitors of acetylcholinesterase. The earliest examples, discovered in Germany by Schrader, were as toxic to the spraymen as to the insects. Little by little, adequate selectivity was built into the molecules, and control over their half-life in the field became part of the molecular design also. 

Unlike the chlorinated hydrocarbons and pyrethroids, the organophosphate insecticides tend towards hydrophilicity, and the more hydrophilic types are taken up by plants from the soil. These systemic insecticides have made a great contribution to selectivity because they poison only those insects that bite the plant. The organophosphates were later joined by the similarly acting carbamate insecticides, less hydrophilic but also less persistent. They are described in Section 13.3. 

The introduction of the organo-phosphorus insecticides, about 1945, greatly widened the spectrum of available types. Like the chlorinated hydrocarbons, these are also nerve poisons, but they act in a quite different way, namely by inhibiting esterases. Unfortunately the early examples, discovered in Germany by Schrader, were as toxic for those who sprayed... 

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