Insecticides Chlordane

A variety of compounds have been evaluated for developmental immunotoxicity. Early work with chlorinated hydrocarbon insecticides revealed that lactating women exposed to the insecticide chlordane, had residues of chlordane in their breast milk.97 A study was performed in mice to determine if chlordane might alter the immune system of mouse pups exposed to chlordane via the dam s milk.98 Female pups displayed... 

No studies were located regarding death in humans after oral exposure to heptachlor or heptachlor epoxide. However, since heptachlor is a major component of the insecticide chlordane, chlordane poisoning can be considered when evaluating heptachlor toxicity data. In the case study of a woman who ingested 6 g of chlordane with suicidal intent and died 9.5 days following ingestion, no information was presented on the composition of the chlordane. Therefore, the amount of heptachlor exposure is unknown, and the effect of other components of chlordane cannot be ruled out (Derbes et al. 1955). 

Roberts, J.R., DeFrietas, A.S.W., and Bidney, M.A.J. Influence of lipid pool size on bioaccumulation of the insecticide chlordane by northern redhorse suckers (Maxostoma macrolepidotimij, J. Fish. Res. Board Can., 34(l) 89-97, 1977. Roberts, M.S., Anderson, R.A., and Swarbrick, J. Permeability of human epidermis to phenolic compounds, /. Pharm. Pharmaa, 29 677-683, 1977. 

All the chlorinated hydrocarbons belonging to this second group of compounds, once used in large amounts, have been banned for use in the U.S. since 1974. They are made by the Diels-Alder reaction, named after two chemists who won the Nobel Prize in 1950 for the discovery of this important reaction. The synthesis of the important insecticides chlordane, heptachlor, aldrin, dieldrin, and endrin are summarized in Fig. 20.4. 

Mahon DC. 1977. Interactions, in rats, between carbon tetrachloride- induced liver cirrhosis and chronic treatment with the organochlorine insecticide chlordane [Abstract]. Dissertations Abstract International 38(9) 4012B. 

Princi F, Spurbeck GH. 1951. A study of workers exposed to the insecticides chlordane, aldrin, dieldrin. Archives of Industrial Hygiene and Occupational Medicine 3 64-72. 

Agricultural chemicals Insecticides [Chlordane Diazinon] Herbicides [H L] [M L]... 

While solid m.p. 95 -96 - C, soluble in organic solvents. An insecticide similar to chlordane. Used to control cotton boll weevil. 

Cyclodienes. These are polychlorinated cycHc hydrocarbons with endomethylene-bridged stmctures, prepared by the Diels-Alder diene reaction. The development of these insecticides resulted from the discovery in 1945 of chlordane, the chlorinated adduct of hexachlorocyclopentadiene and cyclopentadiene (qv). The addition of two Cl atoms across the double bond of the ftve-membered ring forms the two isomers of chlordane [12789-03-6] or l,2,4,5,6,7,8,8-octachloro-2,3,3t ,4,7,7t -hexahydro-4,7-methano-lJT-indene, QL-trans (mp 106.5°C) and pt-tis (32) (mp 104.5°C). The p-isomerhas signiftcantiy greater insecticidal activity. Technical chlordane is an amber Hquid (bp 175°C/267 Pa, vp 1.3 mPa at 25°C) which is soluble in water to about 9 fig/L. It has rat LD qS of 335, 430 (oral) and 840, 690 (dermal) mg/kg. Technical chlordane contains about 60% of the isomers and 10—20% of heptachlor. It has been used extensively as a soil insecticide for termite control and as a household insecticide. 

Experience in the baking industry since World War II has shown that proper use of residual spray materials such as DDT and chlordan will most effectively control these casual invaders. When housekeeping in a bakery is maintained as near perfect as possible, the application of a residual layer of toxic insecticide on areas upon which casual invaders are most likely to travel in seeking harborage will effectively kill the invader individual before it has an opportunity to nest. Experience has borne out this theory in a general way, and specific data are now being collected which will describe it in more scientific terms. 

The total-chlorine method for determining residues of benzene hexachloride, chlordan, and toxaphene has also been used 55) in experiments where it was known that these insecticides had been applied. With benzene hexachloride, which is known to give off-flavor to some crops, it has not been demonstrated that a relation between organic chlorine values and off-flavor exists. In fact, in most cases where off-flavor was attributed to benzene hexachloride, it has not been possible to detect organically bound chlorine. 

Davidow (19), of the Food and Drug Administration, has described a colorimetric method applicable to technical chlordan. The method is based on the observation that when technical chlordan is heated with a mixture of diethanolamine and methanolic potassium hydroxide, a purple color is produced. When known amounts of this insecticide were added to cabbage, pears, and fresh and rancid rat fat, recoveries of 74 to 104% of the insecticide were obtained. However, because two crystalline isomers of chlordan isolated from the technical product do not give a colored reaction product with the reagent, further investigation of the method is being made. The red color obtained when technical chlordan is heated with pyridine, alcoholic alkali, and ethylene glycol monoethyl ether, as described by Ard (2), likewise fails with the crystalline isomers of this insecticide. 

These compounds are much more toxic than chlordan (Table III), and yet are stable toward alkaline reagents (15), being unable to eliminate hydrogen chloride without the formation of a double bond at a bridgehead carbon atom. Thus in this type of compound the conclusion must again be reached that dehydrochlorination with alkali and insecticidal activity have no systematic relationship. 

Methoxychlor [1,1,l-trichloro-2,2-bis(p-methoxyphenyl)-ethane], benzene hexachloride (BHC), chlordan, and toxaphene are chlorinated compounds of recognized importance in the insecticide field. Other chlorinated compounds now undergoing-field testing experiments will, no doubt, soon be added to the list. The need for specific analytical methods is familiar to those concerned with the analysis of formulations containing one or more of the above insecticides. 

Colorimetric methods (3, 6-10), some of which are specific, have been developed for the determination of DDT in small amounts. For benzene hexachloride (hexachloro-cyclohexane), chlordan, and toxaphene, however, specific analytical methods have not been developed, and their residues have been evaluated by the determination of organically bound chlorine. The procedure comprises extraction of the insecticide residue from the sample with benzene or other suitable organic solvent, evaporation of the solvent, treatment of the residue with isopropyl alcohol and metallic sodium, and finally determination by standard methods of the amount of chloride ion formed. 

As Muller had prophesied and indeed hoped, DDT stimulated the discovery of more synthetic insecticides. DDT relatives included chlordane, toxaphene, aldrin, dieldrin, endrin, and heptachlor. Popular substitutes for DDT s family included organophosphates such as parathion, which is a powerful neurotoxin, and carbamates, which are also highly toxic to people. Unlike DDT, parathion and aldicarb have killed and injured many farm workers. Malathion was later developed to be several hundred times less toxic than parathion. 

Overall, insecticides seriously affect invertebrates in the soil, especially insects, but affect microorganisms much less [3,6]. The most toxic OCPs for soil invertebrates are heptachlor and chlordan. They sharply decrease the numbers of almost all invertebrate groups, including insects, earthworms, and ticks [6]. 

Wilson and co-workers [332, 333] have discussed the determination of aldrin, chlordane, dieldrin, endrin, lindane, o,p and p,p isomers of DDT and its metabolites, mirex, and toxaphene in seawater and molluscs. The US environmental Protection Agency has also published methods for organochlo-rine pesticides in water and wastewater. The Food and Drug Administration (USA) [334] has conducted a collaborative study of a method for multiple organochlorine insecticides in fish. Earlier work by Wilson et al. [333, 335] in 1968 indicated that organochlorine pesticides were not stable in seawater. 

Aspila et al. [338] reported the results of an interlaboratory quality control study in five laboratories on the electron capture gas chromatographic determination of ten chlorinated insecticides in standards and spiked and unspiked seawater samples (lindane, heptachlor, aldrin, 5-chlordane, a-chlordane, dield-rin, endrin, p, p -DDT, methoxychlor, and mirex). The methods of analyses used by these workers were not discussed, although it is mentioned that the methods were quite similar to those described in the water quality Branch Analytical Methods Manual [339]. Both hexane and benzene were used for the initial extraction of the water samples. 

Technical chlordane is a mixture of chlorinated hydrocarbons that has been used as an insecticide since its introduction in 1947. Chlordane was the first cyclodiene insecticide to be used in agriculture and was the second most important organochlorine insecticide in the United States in 1976/1977, behind toxaphene, with an estimated annual production of 9 million kg (Nomeir and Hajjar 1987). Chlordane is a leading insecticide in controlling termites, with about 1.2 million homes in the United States alone treated annually for this purpose (Nomeir and Hajjar 1987). 

Chlordane has been detected in both groundwater and surface water at low levels of 0.001 to 0.01 pg/L (USEPA 1988). A high frequency of chlordane detection was noted in seawater samples collected from a Hawaiian marina up to 90% of all samples contained cw-chlordane, and 68% contained trans-chlordane (IARC 1979). Because of chlordane s use as a soil-injected insecticide and its persistence, it has the potential to contaminate groundwater, particularly when it is applied near existing wells (USEPA 1988). 

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