Other Insecticides

Angle CR, Mclntire MS, Meile RL Neurologic sequelae of poisoning in children. J Pe-diatr 73 531-539,1968 

Bell A, Jones AT Fumigation with dichlorethyl ether and chlordane hysterical sequelae. Med J Aust 2 258-263,1958 

Brandt VA, Moon S, Ehler J, et al Exposure to endosulfan in farmers two case studies. Am J Ind Med 39 643-649, 2001 

Czegledi-Janko G, Avar P Occupational exposure to lindane clinical and laboratory findings. British Journal of Industrial Medicine 27 283-286, 1970 Espir MLE, flail JW, Shirreffs JG, et al Impotence in farm workers using toxic chemicals. BMJ 1 423-425, 1970 

Gladen BC, Rogan WJ, Hardy P, et al Development after exposure to polychlorinated biphenyls and dichlorodiphenyl dichloroethene transplacentally and through human milk. J Pediatr 113 991-995, 1988 

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Pesticides include the broad categories of insecticides, fungicides, rodenticides, and herbicides. Insecticides in common use fall into three categories. The chloroinsec-ticides have chlorine in their structure. They are less soluble than the other insecticide forms and much less biodegradable (i.e., more persistent). While they are less acutely toxic, several have been identified as potential carcinogens. Carbamatea are a relatively new form of pesticide. They are less persistent and less... 

The reagent sequence is specific for endosulfan and phosphamidon. Other insecticides, e.g. organochlorine insecticides, such as endrin, aldrin, dieldrin, DDT and BHC, organophosphorus insecticides, such as malathion, parathion, dimethoate, quinalphos, phorate and fenitrothion, or carbamate insecticides, such as baygon, car-baryl and carbofuran do not react. Neither is there interference from amino acids, peptides or proteins which might be extracted from the biological material together with the pesticides. 

Mental disturbances have been reported after organophosphate exposure. Neuropsychiatric symptoms occurred in two aerial applicators, one of whom used methyl parathion as well as other insecticides. One of these pilots had high levels of exposure to a mixture containing methyl parathion, toxaphene, and Dipterex when his clothing became saturated when the tank of his aircraft accidentally overflowed. Several months after the accident, the subject complained of anxiety, dizziness, emotional lability, and frequent and severe disagreements with family members and associates. Similar observations had been... 

Inevitably, terrestrial invertebrates are susceptible to the toxicity of OPs used in the field. The honeybee is one species of particular importance, and the use of OPs and other insecticides on agricultural land has been restricted to minimize toxicity to this species. One practice has been to avoid application of hazardous chemicals to crops when there are foraging bees. The use of some compounds, for example, triazophos, has been restricted because of very high toxicity to honeybees. 

The variation in toxicity of common organophosphate insecticides is exemplified in Table 4.29. The range of chlorinated hydrocarbon insecticides (Table 4.30) has, with the exception of Endrin and Isodrin, somewhat lower oral and dermal toxicities. The toxicities of a range of other insecticides, fungicides, herbicides and rodenticides are summarized in Table 4.31. 

Recently a colorimetric test for methoxychlor residues was proposed by Fairing (27). The methoxychlor sample is treated with alcoholic potassium hydroxide, the reaction product is extracted with ether, the ether is removed, and the residue is treated with concentrated sulfuric acid. An intense cherry-red color is developed. No other insecticide has been found to interfere, and the reaction is sensitive to about 5 micrograms of methoxychlor. 

As the value of these two new chemicals for insecticides became more evident, the need for extended experimental and test work was definitely established. It was necessary to determine chemical formulas, work out analytical methods, obtain knowledge of various physical and chemical characteristics, and complete evaluation of insecticidal action as well as toxicity and effect of residues. Toxicity was concerned with not only insects but humans and other warm-blooded animals. Residual studies included information on persistence and type and amount of residue. This information, once accumulated, must be correlated with similar information on other insecticides. 

Field test work with technically pure gamma isomer of hexachlorocyclohexane has been extensive and involved and is being continued. It was necessary to know such factors as insecticidal value in field applications as compared to other insecticides, as well as residual life, residue from the poison standpoint, and residual taste or odor factors. These factors have been worked out on numerous crops and some of the results are dealt wTith in this paper. Because the pure gamma isomer was found to be effective on insects in the soil as well as on insect infestations on plants, its residual life in soil of all types and effects on tuber and root crops were also of major importance. 

In spite of the fact that parathion is such an amazing insecticide, it cannot replace all other insecticides. As a matter of fact, it can be used beneficially with a number of other insecticides and fungicides. 

Tests of dieldrin against cotton pests have not been as extensive, but the Mississippi 1950 Cotton Insect Control Recommendations state that it kills a larger proportion of immature weevils in squares than any other insecticide tested thus far and is considered very promising for cotton insect control (4). 

The aforementioned series of reactions provides a basis for a colorimetric analytical method for Compound 118 in which the commonly used agricultural chemicals do not interfere. The procedure described herein permits the estimation of as little as 10 micrograms of Compound 118, and has been successfully applied to the analysis of this insect toxicant in insecticidal dusts, in film residues on glass and paper, in human and animal urine, and in mixture with other insecticides. Application of this procedure to the determination of Compound 118 in milk and in spray and dust residues on plants appears promising. 

A new insecticide must be compatible with other insecticides, fungicides, and supple-... 

A procedure for the determination of 7-benzene hexa-chloride and DDT in benzene hexachloride-DDT-sul-fur formulations, employing partition chromatography, is described. The procedure has also been applied to the assay of 1,1,1 -trichloro-2,2-bis(p-methoxyphenyl)-ethane in technical methoxychlor. Results of separation of other insecticidal ingredients are discussed. 

The method has been applied to the separation of other insecticidal ingredients. 

Pyrethroid insecticides are generally recognized as potent neurotoxicants that interfere with nerve membrane function by interaction with the sodium channel (Elliott and Janes 1978 Vijverberg et al. 1982 Gilbert et al. 1989 Haya 1989). Synthetic pyrethroids are more toxic against insect pests, up to 10 times more potent in some cases, than other insecticides now in general use (Bradbury... 

Hintzen EP, Lydy MJ, Belden JB (2009) Occurrence and potential toxicity of pyrethroids and other insecticides in bed sediments of urban streams in central Texas. Environ Pollut 157 110-116... 

Pyrethrum has been used as an insecticide for around 150 years, and there has been no other insecticide which has so successfully contributed to the control of sanitary pests. Numerous analogs have been developed by chemists worldwide since the elucidation of the chemical structure of pyrethrins, which are the insecticidal ingredients of pyrethrum. As a result, their application has expanded extensively to various fields. To date, many eminent books have been published by scientists in this field and have contributed to advancing pyrethroid science. 

It is interesting to note that the toxic sodium fluoroacetate (above, p. 11) occurs in the poisonous South African plant gifblaar (Dichapetalum cymosum, PI. I). It has recently been shown that sodium fluoroacetate is a highly effective systemic insecticide, but it is difficult to say exactly how this substance will be applied on a large scale.6 There are many other insecticides containing fluorine and phosphorus, and special precautions must be taken when handling these toxic compounds. 

Among other insecticides may be mentioned systox, first synthesized by Schrader.1 Ripper calls for caution in its use on food crops until more is known about the toxic metabolites. 

Field spray studies have been carried on using benzene hexachloride and similar insecticides. In Brazil benzene hexachloride appeared to have a toxic effect on coffee trees. It has been the source of a bad flavor in coffee in Africa and also in Brazil, which was a further reason for abandoning its use. Work with so-called deodorized benzene hexachloride compounds and other insecticides is now in progress. 

Ivie, G.W. and Casida, J.E. Photosensitizers for the accelerated degradation of chlorinated cyclodienes and other insecticide chemicals exposed to sunlight on bean leaves, / Agric. Food Chem., 19(3) 410-416, 1971a. 

Insects have developed resistance to cyanide, chlorinated hydrocarbons, organophosfiiates, carbamates, synthetic pyrethroids, and other insecticides ( ). This is not surprising vrtien considering the same complex of detoxifying enzymes, mainly r resented by hydrolytic, conjugative, and oxidative enzymes 9) is capable of detoxifying natural toxins as well as man-made materials. This ability is due to apprcpriate enzymes and/or isozymes that results in broad-substrate capabilities. For insects that feed on a wide variety of hosts (polyphagy), the spectrum of toxins that can be dealt with is truly remarkable. 

Beneficial nematodes Insecticide for soil grubs Diazinon, carbaryl, or other insecticide... 

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... 

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