60- 57-1 Dieldrin

Colorless to light tau solid mild odor melts at 176°C (348°F) vapor pressure 3.1 x 10 torr at 20°C (68°F) iusoluble iu water, moderately soluble iu most orgauic solveuts. 

Highly toxic toxic symptoms similar to these of aldrin affects central nervous system, liver, kidneys, and skin causes headache, dizziness, nausea, vomiting, tremor, ataxia, clonic and tonic convulsions, and respiratory failure oral LD50 value (mice) 38 mg/kg causes liver cancers in animals inadequate evidence in humans RCRA Waste Number P037. 

Exposure to many organochlorine pesticides has been linked to an increased risk of Parkinson s disease. In this context, dieldrin has been the most implicated of all. Dieldrin has been found, during postmortem, in the brain tissues of humans with Parkinson s disease, indicating that it promotes dopaminergic degeneration. Various neurotoxic studies following exposure to dieldrin have been conducted in both cell cultures and animal models. Such studies indicated that dieldrin-induced neurotoxicity 

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A chromatographic analysis for the chlorinated pesticide Dieldrin gives a peak with a retention time of 8.68 min and a baseline width of 0.29 min. How many theoretical plates are involved in this separation Given that the column used in this analysis is 2.0 meters long, what is the height of a theoretical plate ... 

Dieldrin [60-57-1] or l,2,3,4,10,10-hexachloro-l,4,4t ,5,8,8t -hexahydro-6,7-epoxy-l,4- <7o, Aro-5,8-dimethanonaphthalene (34) (mp 176°C, vp 0.4 mPa at 20°C) is formed from aldrin by epoxidation with peracetic or perben2oic acids. It is soluble in water to 27 / g/L. Aldrin and dieldrin have had extensive use as soil insecticides and for seed treatments. Dieldrin, which is very persistent, has had wide use to control migratory locusts, as a residual spray to control the Anopheles vectors of malaria, and to control tsetse flies. Because of environmental persistence and propensity for bio accumulation, registrations in the United States were canceled in 1974. 

Endrin [72-20-8] is l,2,3,4,10,10-hexachloro-l,4,4t ,5,8,8t -hexahydro-6,7-epoxy-l,4- <7o, <7o-5,8-dimethanonaphthalene (35) (mp 245 dec, vp 0.022 mPa at 25°C) and is soluble in water to 23 / g/L. It is produced by a Diels-Alder reaction of hexachloronorbomadiene with cyclopentadiene, followed by epoxidation. This reaction produces the endo,endo isomer of dieldrin, which is less stable and more toxic with rat LD q values of 17.8 and 7.5 (oral) and 15 (dermal) mg/kg. It is used as a cotton insecticide but because of its high toxicity to fish it has been restricted. 

Mode of Motion. The cyclodienes, like lindane and toxaphene, affect the nerve axon produciag hyperactivity, convulsions, prostration, and death. The biochemical lesion is the competitive inhibition of the y-aminobutyric acid (GABA) neurotransmitter binding site of the nerve axon. Spray workers with lengthy exposure to dieldrin have suffered from prolonged and repeated central nervous system disturbances produciag epileptiform coavulsioas. Similar disturbances occurred ia workers heavily exposed to chlordecoae. 

DDT at 0.25—0.75% and dieldrin at 0.05% appHed during dry cleaning or by spraying fabrics with aqueous emulsions of equivalent strength were formerly used extensively as semipermanent fabric protectants. However, these are no longer used because of problems of environmental contamination. 

Polychlorinated Pesticides. A once substantial but now diminished use for DCPD is in the preparation of chlorinated derivatives for further use or synthesis into pesticide compounds (see Insectcontrol technology). Soil permanence and solubiUty of the products in human fatty tissues have considerably restricted the use of these compounds. The more prominent chlorinated pesticides were aldrin, dieldrin, chlordane, and heptachlor, all of which use hexachorocyclopentadiene as a starting material. Aldrin and dieldrin are no longer used in the U.S. Chlordane and heptachlor are stiU produced, but only for export use. 

The concentration of the residues of isomers of HCH, DDT, Eindane, Aldrine, Dieldrine, Heptachlorine and Heptachloroepoxide and Endosulphanes in investigated samples ai e within norms of currently applied Standards while concentration of organochlorine insecticides are greatly below the MAC in range of 0.00-23.53T0 mg/dm . 

Aldrin, chlordecone (Kepone), 2,4-D, DDT and metabolites, dieldrin, endosulfan, endrin, f]- and y-HCH (lindane), linuron, methoxychlor, mirex... 

Much controversy has arisen regarding the ability of mixtures of weakly estrogenic compounds to act synergistically, notably the synergistic potential of mixtures of PCBs or of the insecticides dieldrin and toxaphene. " Recent studies suggest that the action of mixtures is at least additive. "... 

Although eggshell thinning attributable to DDE exposure has occurred in birds in the UK, the lethal and siiblethal effects of the cyclodiene pesticides aldrin, dieldrin and heptachlor are also believed to have contributed to the population effects, particularly in the case of the sparrowhawk and peregrine falcon. Following the withdrawal of DDT and the cyclodienes from use in the UK, Europe and North America, bird of prey populations that were severely affected have shown partial or complete recovery. ... 

In 1974, the Harmonized Monitoring Programme was set up by the Department of the Environment (DoE). The objective was to provide a network of sites at the lower end of catchments, where water quality data could be collected and analysed in a nationally consistent manner, allowing the loads of materials carried through river catchments into estuaries to be estimated and long-term trends in river quality to be assessed. The complete list of substances to be monitored is diverse and specifies about 115 substances. The pesticides aldrin, dieldrin, y-HCH, heptachlor, p,p -DDT and p,p -DDE are included. Figures 1 and 2 show the downward trend of y-HCH and dieldrin over the past 20 years at the Harmonized Monitoring Sites. This confirms that reductions in environmental concentrations have been achieved, particularly over the past 10 years. 

The concentrations of dieldrin show a marked decline throughout the 1980s following the ban on its use. The concentrations of y-HCH have also declined during the same period, but the reduction is not as significant. This is probably due to the fact that y-HCH still has a wide variety of uses in the UK in agriculture. 

Figure 2 Dieldrin in rivers in Great Britain (% distribution of eoneentrations). (Data from Harmonized Monitoring Sites)...

Pesticidal L S DDT BHC Aldrin Dieldrin Pesticides Wood treatment... 

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