Chlorinated Cyclodiene Insecticide Research Articles

Theoretical study of fluorinated bioisosteres of organochlorine compounds as effective and eco-friendly pesticides.

Chlordane is a worldwide banned organochlorine insecticide because of its hazard to animal and human health. It is also a persistent organic pollutant, which can affect either the soil or the aquatic life. The same applies to other chlorinated cyclodiene insecticides, such as dieldrin and aldrin. In turn, organofluorine compounds have a widespread use in agriculture. Therefore, density functional calculations and docking studies showed that the bioisosteric replacement of chlorines in the above-mentioned compounds by fluorines improves some physicochemical parameters used to estimate the toxicity and environmental risk of these compounds, as well as the ligand-enzyme (GABAA receptor-chloride channel complex) interactions related to their insecticidal activity. This work is an effort to provide an improved new class of organofluorine pesticides.

Biodegradability and biodegradation pathways of chlorinated cyclodiene insecticides by soil fungi.

An aerobic dieldrin-degrading fungus, Mucor racemosus strain DDF, and two aerobic endosulfan-degrading fungal strains, Mortierella sp. strains W8 and Cm1-45, were isolated from soil contaminated with organochlorine pesticides. Strain DDF degraded more than 90% dieldrin during 10-days of incubation at 25°C and showed the production of a small amount of aldrin trans-diol. Moreover, strain DDF reduced levels of aldrin trans-diol while producing unknown metabolites that were determined to be aldrin trans-diol exo- and endo-phosphates. On the other hand, Mortierella sp. strains W8 and Cm1-45 degraded more than 70% and 50% of α and β-endosulfan, respectively, over 28 days at 25°C, in liquid cultures containing initial concentrations of 8.2 µM of each substance. Only a small amount of endosulfan sulfate, a persistent metabolite, was detected in the both cultures, while these strains could not degrade endosulfan sulfate when this compound was provided as the initial substrate. Both strains generate endosulfan diol as a first step in the degradation of endosulfan, then undergo further conversion to endosulfan lactone.

Gas phase pyrolysis of endosulfan and formation of dioxin precursors of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/F)

This article reports the results of a computational and experimental study on the thermal degradation of endosulfan, a broad-spectrum chlorinated cyclodiene insecticide. The objective of the study was to identify its decomposition pathways, and to gain an understanding of the mechanism of formation of toxic species including polychlorinated dibenzo-p-dioxins (PCDD) and polychlorinated dibenzofurans (PCDF) and their precursors. We implemented pyrolysis experiments in a tubular reactor and identified the pyrolysis products and demonstrate good qualitative agreement between the experimental species measurements and quantum chemical calculations. A sampling system intercepted the gaseous products exiting the reactor which were analysed by FTIR spectroscopy and trapped (at −10°C) volatile organic compounds (VOC) generated from the thermal decomposition of endosulfan were analysed by GC/MS. Decomposition commences at about 573K in a flow reactor at a residence time of 5s. The initial primary decomposition reaction of endosulfan involves a retro Diels–Alder elimination to form hexachlorocyclopentadiene (HCCP) and 4,7-dihydro-1,3,2-dioxathiepine-2-oxide (2HDTO). Under these conditions, 2HDTO decomposes via two competing reaction channels, both eliminating SO2. At reaction temperatures of 663K and above, fission of a Cl atom results in the formation of endosulfan radical, which promotes further decomposition of endosulfan via a low barrier free radical pathway. As the temperature increases further, we observe a rise in secondary products including pentachlorocyclopentadiene (PCCP), tetrachlorostyrene (TCS) and pentachlorostyrene (PCS). At 823K, chlorinated benzene products were identified comprising pentachlorobenzene and isomers of tetrachlorobenzenes which are known precursors for polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans PCDD/PCDF under oxidative conditions. Under oxidative conditions (10% oxygen), PCDD/PCDF congeners are formed, dominated by mono- to octa- chlorinated dibenzofurans and tetra- to octa- chlorinated dibenzo-p-dioxins.

Amelioration Effect of Emblica officinalis Extract on Ovary in Endosulfan Induced Swiss Albino Mice

Background: In the present time use of pesticides has become very common by the farmers for the better yield of crops. Endosulfan, a chlorinated cyclodiene insecticide, is widely and very liberally used in agricultural sector. But it has created deleterious effects on human health. Objective: In the present study amelioration effect of Emblica officinalis (E. officinalis) extract on ovary in Endosulfan induced Swiss albino mice was studied. Materials and Methods: Three groups were formed, each with six mice. The control group of mice received distilled water as drinking water. The second group was exposed to Endosulfan @ 3 mg/kg body weight daily for 6 weeks by Gavage method. The third group was exposed to Endosulfan @ 3 mg/kg body weight daily for 6 weeks followed by 6 weeks exposed to E. officinalis (100 mg/kg body weight) extract. Animals were sacrificed after the schedule treatment. Results and Discussion: Light microscopic observations showed various histopathological deformities in sections of treated ovary and improper development of follicle such as detached ova Original Research Article Sinha and Kumari; BJPR, 11(2): 1-9, 2016; Article no.BJPR.17669 2 and degeneration of follicular cells due to Endosulfan exposure were also found. The present studies also indicate that alterations were found to be significantly ameliorated in E. officinalis extract treated group. Conclusion: It may be concluded from this study that E. officinalis have a potent capacity to control Endosulfan induced toxicity.

ChemInform Abstract: Studies on the Dechlorination and Detoxification of Organochlorine Compounds. Part 2. Chlorinated Cyclodiene Insecticides and the Polychlorinated Insecticide ′Mirex′.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Melatonin protects against endosulfan‐induced oxidative tissue damage in rats

Endosulfan is a chlorinated cyclodiene insecticide which induces oxidative stress. In this study, we investigated the possible protective effect of melatonin, an antioxidant agent, against endosulfan (Endo)-induced toxicity in rats. Wistar albino rats (n = 8) were administered endosulfan (22 mg/kg/day orally) followed by either saline (Endo group) or melatonin (10 mg/kg/day, Endo + Mel group) for 5 days. In other rats, saline (control group) or melatonin (10 mg/kg/day, Mel group) was injected for 5 days, following corn oil administration (vehicle of endosulfan). Measurement of malondialdehyde (MDA) and glutathione (GSH) levels, myeloperoxidase (MPO) activity and collagen content were performed in liver and kidney. Furthermore, aspartate aminotransferase (AST), alanine aminotransferase (ALT), blood urea nitrogen (BUN), and creatinine levels, lactate dehydrogenase (LDH) activity were measured in the serum samples, while tumor necrosis factor-alpha (TNF-alpha), interleukin-beta (IL-beta) and total antioxidant capacity (AOC) were assayed in plasma samples. Endosulfan administration caused a significant decrease in tissue GSH and plasma AOC, which was accompanied with significant rises in tissue MDA and collagen levels and MPO activity. Moreover, the proinflammatory mediators (TNF-alpha and IL-beta), LDH activity, AST, ALT, creatinine and BUN levels were significantly elevated in the endosulfan-treated rats. On the other hand, melatonin treatment reversed all these biochemical alterations induced by endosulfan. Our results suggest that oxidative mechanisms play an important role in endosulfan-induced tissue damage and melatonin, by inhibiting neutrophil infiltration, balancing oxidant-antioxidant status and regulating the generation of inflammatory mediators, ameliorates oxidative organ injury as a result of endosulfan toxicity.

Effect of tween 80 added to the soil on the degradation of endosulfan by Pseudomonas aeruginosa

Endosulfan, a chlorinated cyclodiene insecticide is of environmental concern because of its apparent persistence and toxicity to many non target organisms. Endosulfan is hydrophobic and persists in soil for more than a year. To overcome the problem of hydrophobic and limited availability, surfactants play a major role in soil remediation. In the present study, the effect of Tween 80 added to the soil on the degradation of endosulfan by Pseudomonas aeruginosa at different pH (7.0 and 8.5) was studied. The addition of synthetic surfactant Tween 80 enhanced the solubility and degradation of endosulfan. A significant degradation (94%) was observed in pH 8.5 and Tween 80 added soil; the bacterial population in the treatment unit T8 was 75 × 109 CFU/g of soil. The unit T4 inoculated at pH 8.5 showed 86 % alpha and 60 % beta endosulfan degradation, the bacterial population was 73 × 108 CFU / g of soil. The degradation of both the isomers were observed and accompanied with formation of endodiol and endosulfan sulfate.

STEREOSELECTIVE METABOLISM OF ENDOSULFAN BY HUMAN LIVER MICROSOMES AND HUMAN CYTOCHROME P450 ISOFORMS

Endosulfan (6,7,8,9,10,10-hexachloro-1,5,5a,6,9,9a-hexahydro-6,9-methano-2,3,4-benzo(e)dioxathiepin-3-oxide) is a broad-spectrum chlorinated cyclodiene insecticide. This study was performed to elucidate the stereoselective metabolism of endosulfan in human liver microsomes and to characterize the cytochrome P450 (P450) enzymes that are involved in the metabolism of endosulfan. Human liver microsomal incubation of endosulfan in the presence of NADPH resulted in the formation of the toxic metabolite, endosulfan sulfate. The intrinsic clearances (CL(int)) of endosulfan sulfate from beta-endosulfan were 3.5-fold higher than those from alpha-endosulfan, suggesting that beta-endosulfan would be cleared more rapidly than alpha-endosulfan. Correlation analysis between the known P450 enzyme activities and the rate of the formation of endosulfan sulfate in the 14 human liver microsomes showed that alpha-endosulfan metabolism is significantly correlated with CYP2B6-mediated bupropion hydroxylation and CYP3A-mediated midazolam hydroxylation, and that beta-endosulfan metabolism is correlated with CYP3A activity. The P450 isoform-selective inhibition study in human liver microsomes and the incubation study of cDNA-expressed enzymes also demonstrated that the stereoselective sulfonation of alpha-endosulfan is mediated by CYP2B6, CYP3A4, and CYP3A5, and that that of beta-endosulfan is transformed by CYP3A4 and CYP3A5. The total CL(int) values of endosulfan sulfate formation catalyzed by CYP3A4 and CYP3A5 were consistently higher for beta-endosulfan than for the alpha-form (CL(int) of 0.67 versus 10.46 microl/min/pmol P450, respectively). CYP2B6 enantioselectively metabolizes alpha-endosulfan, but not beta-endosulfan. These findings suggest that the CYP2B6 and CYP3A enzymes are major enzymes contributing to the stereoselective disposition of endosulfan.

Biodegradation of the organochlorine insecticide, endosulfan, and the toxic metabolite, endosulfan sulfate, by Klebsiella oxytoca KE-8

Biodegradation of endosulfan, a chlorinated cyclodiene insecticide, is generally accompanied by production of the more toxic and more persistent metabolite, endosulfan sulfate. Since our reported endosulfan degrader, Klebsiella pneumoniae KE-1, failed to degrade endosulfan sulfate, we tried to isolate an endosulfan sulfate degrader from endosulfan-polluted soils. Through repetitive enrichment and successive subculture using mineral salt medium containing endosulfan or endosulfan sulfate as the sole source of carbon and energy, we isolated a bacterium capable of degrading endosulfan sulfate as well as endosulfan. The bacterium KE-8 was identified as Klebsiella oxytoca from the results of 16S rDNA sequence analysis. In biodegradation assays with KE-8 using mineral salt medium containing endosulfan (150 mg l(-1)) or endosulfan sulfate (173 mg l(-1)), the biomass was rapidly increased to an optical density at 550 nm of 1.9 in 4 days and the degradation constants for alpha- and beta-endosulfan, and endosulfan sulfate were 0.3084, 0.2983 and 0.2465 day(-1), respectively. Analysis of the metabolites further suggested that K. oxytoca KE-8 has high potential as a biocatalyst for bioremediation of endosulfan and/or endosulfan sulfate.

Development of a monoclonal immunoassay selective for chlorinated cyclodiene insecticides.

Organochlorine pesticides still generate public health concerns because of their unresolved health impact and their persistence in living beings, which is demanding appropriate analytical techniques for their monitoring. In this study, an enzyme-linked immunosorbent assay based on monoclonal antibodies (MAbs) for the detection of an important group of organochlorine pesticides, the cyclodiene group, has been developed. With this aim, several hapten-protein conjugates, characterized by exposure of the common hexachlorinated bicyclic (norbornene) moiety and differing in the linking structure to the carrier protein, were prepared. From mice immunized with these conjugates, several MAbs with the ability to sensitively bind the majority of cyclodienes were obtained. Among them CCD2.2 MAb displaying the broadest recognition to cyclodiene compounds (endosulfan, dieldrin, endrin, chlordane, heptachlor, aldrin, toxaphene: I(50) values in the 6-25 nM range) was selected for the assay. Interestingly, this MAb showed certain stereospecificity toward other polychlorinated cycloalkanes because the gamma-isomer of hexachlorocyclohexane (lindane) was also very well recognized (I(50) value of 22 nM). This immunoassay is potentially a very valuable analytical tool for the rapid and sensitive determination of cyclodiene insecticides and related compounds, which in turn may contribute to the understanding of the biological activities and of the overall environmental impact of these persistent organic pollutants.

Dieldrin stimulates biliary excretion of 14C-benzo[a]pyrene polar metabolites but does not change the biliary metabolite profile in rainbow trout (Oncorhyncus mykiss).

Activities of hepatic microsomal and cytosolic epoxide hydrolases, accumulation of dieldrin in liver, and in vivo metabolism and disposition of the polycyclic aromatic hydrocarbon (PAH), benzo[a]pyrene (BP), were examined in rainbow trout pretreated with dieldrin, a chlorinated cyclodiene insecticide. Rainbow trout were fed 0.3 mg dieldrin/kg/day for 9 weeks and the same dose of dieldrin for 9 weeks, followed by 3 weeks on control diet (12 weeks). Fish then received an intraperitoneal (ip) challenge dose of 14C-BP (10 micromol/kg). Dieldrin pretreatment significantly elevated the concentration of 14C-BP in bile (142% and 200% at 9 and 12 weeks, respectively), but not liver or fat. Extraction of bile subsamples confirmed dieldrin pretreatment significantly stimulated total biliary excretion of 14C-BP polar metabolites (244% and 221% at week 9 and 12, respectively). The complex metabolism of BP characterized the in vivo state of the CYP system, UDP-glucuronyltransferases, and sulfotransferases. Bile was extracted and then hydrolyzed by beta-glucuronidase and arylsulfatase to regenerate BP metabolites conjugated by phase II enzymes. Evaluation of biliary polar metabolite profiles of 14C-BP revealed no significant differences between control and dieldrin-fed fish. There was no selective enhancement of any particular metabolite, or formation of a novel metabolite with dieldrin pretreatment. This research confirmed that enhanced biliary excretion, following chronic dieldrin exposure, was not explained by induction of xenobiotic metabolizing enzymes. The results are consistent with induction of hepatic intracellular trafficking proteins in dieldrin-fed fish.

Effect of endosulfan on ovarian compensatory hypertrophy in hemicastrated albino mice

Endosulfan, a chlorinated cyclodiene insecticide, was administered orally at 1.5, 3, 6, and 9 mg/kg per day to normal hemicastrated virgin mice for 15 consecutive days to examine the effect on ovarian function. Sham-operated and hemicastrated control mice were administered a similar volume of olive oil. The vaginal smear and body weight of the mice were recorded daily and mice were sacrificed on day 16. The remaining left ovary, uterus, kidney, adrenal, liver, thymus, and thyroid were removed and weighed. The left ovary from each animal was serially sectioned and stained for histologic studies. The hemicastrated control mice had a 40.5% increase in weight of the remaining left ovary and a significant increase in healthy and atretic follicles when compared with sham-operated controls. The remaining left ovaries of mice treated with 1.5 mg endosulfan had a 37.2% increase in weight with no significant difference in ovarian weight and or in the healthy and atretic follicles when compared with hemicastrated olive oil-treated controls. However, treatment with 3, 6, and 9 mg endosulfan resulted in weight increases in the remaining left ovary of only 14.9, 7.4, and 0.8% and a significant decrease in healthy follicles with a concomitant increase in the number of atretic follicles compared to the olive oil-treated controls. There was no significant change in the number of estrous cycles or the duration of each phase of the estrous cycle with 1.5 and 3 mg/kg per day endosulfan. However, there was a significant decrease in the number of estrous cycles, and the duration of estrus and metestrus with a concomitant significant increase in the duration of the diestrus phase with 6 and 9 mg/kg per day endosulfan treatment when compared with hemicastrated olive oil-treated controls. There were no significant change in body weight or the weights of the uterus, kidney, adrenal, liver, thymus, or thyroid after endosulfan treatment. These observations show that endosulfan treatment caused a significant decrease in compensatory ovarian hypertrophy. An increase in the number of atretic follicles and disruption of the estrous cycle may have been due to a direct effect on the ovary or to effects on the hypothalamo–hypophysial–ovarian axis.

Selective induction of the CYP3A family by endosulfan and DNA-adduct formation in different hepatic and hepatoma cells

Endosulfan, a chlorinated cyclodiene insecticide, is known to cause a significant enhancement of altered hepatic foci in rats and to be a potent inhibitor of gap-junctional intercellular communication in vitro. Both of these features are common to many tumor promoters. However, long-term studies in rodents provide no evidence that it is carcinogenic or genotoxic. In the present study, endosulfan genotoxicity is evaluated and the formation of DNA adducts is investigated in three types of cultured hepatic cells (rodent, bird, and human). DNA-adduct formation in response to endosulfan treatment is measured by the 32P-postlabelling method. The results have shown a high genotoxicity of endosulfan only in rat and human cells. Therefore, to better understand these findings and because nothing is known about the xenobiotic-metabolizing enzymes involved in endosulfan metabolism, we have attempted to identify the cytochromes P450 induced, which can transform endosulfan into reactive intermediates capable of interacting with DNA. To examine if endosulfan induces CYP1A-, CYP2B-, or CYP3A-family transcripts, we measured transcript levels by Northern blot and RT-PCR analyses. Endosulfan appears to selectively induce expression of the CYP3A gene family. It is a potent inducer of CYP3A1 mRNA in rat and is also shown, by RT-PCR. to increase the CYP3A7 transcript level in Hep G2 human hepatoma cells. In contrast, in fetal quail hepatocytes, CYP3A is not expressed and no endosulfan-DNA adducts are formed.

Protracted neurotoxicity from chlordane sprayed to kill termites.

Over 250 adults and children were exposed to chlordane when the wooden building surfaces and soil around an apartment complex were sprayed in 1987. Two hundred-sixteen adults had neurobehavioral functions measured and completed questionnaires for symptom frequency, mood status, confounding factors, and medical, rheumatic, and respiratory disorders in 1994. Measurements included simple and choice reaction time, balance, blink reflex latency, color vision, cognitive, perceptual motor, memory, and recall functions. We analyzed 216 exposed and 174 referent adults. Age, educational level, weight, height, and gender ratio were similar for the exposed and referent groups. Performance of balance, reaction times, Culture Fair, digit symbol, verbal recall, and trail-making were significantly impaired in exposed persons compared to referents. Mood-state scores were elevated, as were the frequencies of respiratory, neurobehavioral, and rheumatic symptoms. In contrast, long-term memory function was similar in both groups, consistent with its status before exposure. There was no identified bias or confounding factors. Chlordane exposure was associated with protracted impairment of neurophysiological and psychological functions. The central nervous system is the most important target of chlorinated cyclodiene insecticides. Human exposure should be prohibited.

The Relevance of Fat Content in Toxicity of Lipophilic Chemicals to Terrestrial Animals with Special Reference to Dieldrin and 2,3,7,8-Tetrachlorodibenzo- p-dioxin (TCDD)

Lipophilic chemicals such as chlorinated hydrocarbon insecticides and other persistent chemicals such as 2,3,7,8-tetrachlorodibenzo- p-dioxin (TCDD) are fat soluble chemicals and are readily bioconcentrated in animal fat depots. The modifying role of the body fat content in the toxicity of chlorinated cyclodiene insecticides to insects and in the toxicity of TCDD to different mammals was investigated. The single oral acute 30-day LD 50 data of TCDD in different mammals are presented and correlated with their total body fat content. A two linear regression equation with log/log values was obtained. It is concluded that the storage of TCDD and other related lipophilic and persistent chemicals in lipids of organisms is, in a sense, a detoxication mechanism by which the compounds are removed from sites of action and/or receptors. Therefore, terrestrial organisms such as insects and mammals with higher total body fat content can accumulate and tolerate higher chlorinated hydrocarbon insecticide and TCDD doses than organisms with lower fat content. The different sensitivity of mammals of various species, strains, body weight, sex, age, etc. to acute toxicity of TCDD and related lipophilic persistent chemicals can mainly be explained by differences in total body fat content.

Inhibitory effects of endosulfan on gap junctional intercellular communication in WB-F344 rat liver cells and primary rat hepatocytes.

The chlorinated cyclodiene insecticide endosulfan is a potent inhibitor of gap junctional intercellular communication (GJIC) in vitro, a property shared by many tumour promoters and suggested to indicate an intrinsic tumour-promoting potential. However, endosulfan did not act as a tumour promoter in an altered hepatic foci assay in the rat in vivo, and ambiguous results regarding the carcinogenic potential of endosulfan have emerged from long-term studies in rodents. In the present study the GJIC-inhibitory potentials of the two isomers of endosulfan were investigated in WB-F344 rat liver epithelial cells and primary rat hepatocytes. The results show that both isomers are inhibitors of GJIC. However, beta-endosulfan (ENDO beta) is a more potent inhibitor of GJIC in primary rat hepatocytes than alpha-endosulfan (ENDO alpha), whereas the two isomers were equally potent as inhibitors of GJIC in WB-F344 rat liver cells. In primary rat hepatocytes membrane-permeant dibutyryl cyclic AMP (dB-cAMP) counteracts the inhibitory effect of ENDO beta without affecting the effect of ENDO alpha. However, in WB-F344 rat liver cells dB-cAMP failed to prevent the inhibitory effects of either ENDO alpha or ENDO beta. In addition, studies in WB-F344 rat liver cells show that ENDO alpha beta does not decrease the intracellular cAMP concentration. Thus, it is unlikely that ENDO alpha beta or its isomers and metabolites inhibit GJIC by lowering the intracellular cAMP concentration. Furthermore, comparison of the effective doses and recovery times imply that GJIC in WB-F344 rat liver cells is more sensitive to treatment by ENDO alpha beta, its isomers and metabolites than GJIC in primary rat hepatocytes. Thus, the present results demonstrate significant differences between primary rat hepatocytes and WB-F344 rat liver cells in the response of their GJIC to endosulfan.

The insecticide endosulfan and its two stereoisomers promote the growth of altered hepatic foci in rats.

The non-genotoxic, chlorinated cyclodiene insecticide endosulfan was studied for its ability to act as a tumour promoter in a two-stage, altered hepatic foci bioassay in male Sprague-Dawley rats. Two stereoisomers of endosulfan, alpha-endosulfan (ENDO alpha) and beta-endosulfan (ENDO beta) were used, as well as a commercially-occurring mixture of the alpha- and beta-isomers (ENDO alpha beta). The animals were initiated by intraperitoneal injection of nitrosodiethylamine 24 h after a two-thirds-partial hepatectomy. Five weeks later the animals were transferred to diets containing 30, 100 and 300 p.p.m. of either ENDO alpha beta, ENDO alpha or ENDO beta. The study was terminated 25 weeks after initiation and the development of foci of gamma-glutamyltranspeptidase-positive hepatocytes was evaluated by stereological methods. The results show that endosulfan and its two stereoisomers promote the development of altered hepatic foci, suggesting that endosulfan is a tumour-promoting agent acting by clonal expansion of initiated cells.

Studies on the dechlorination and detoxification of organochlorine compounds II. Chlorinated cyclodiene insecticides and the polychlorinated insecticide ‘mirex’

AbstractIn the first paper on the dechlorination of organochlorine compounds, results were reported for polychlorinated biphenyls and polychlorinated naphthalenes, using the Ni2B in‐situ catalytic dechlorination technique. In the present study, the work has been extended to the dechlorination and detoxification of some chlorinated polycyclic hydrocarbons belonging to a cyclodiene insecticide group (dieldrin, aldrin and endrin). In addition, a cage‐structured polychlorinated insecticide, ‘mirex’, has also been investigated. During the dechlorination process, intermediates were detected by GC/MS and identified by their characteristic mass fragments and retention in mass.

ChemInform Abstract: POLARIZATION AND POLARIZABILITY STUDY OF SOME CHLORINATED CYCLODIENE INSECTICIDES

Chemischer InformationsdienstVolume 8, Issue 8 Physical Organic Chemistry ChemInform Abstract: POLARIZATION AND POLARIZABILITY STUDY OF SOME CHLORINATED CYCLODIENE INSECTICIDES K. E. CALDERBANK, K. E. CALDERBANKSearch for more papers by this authorR. K. PIERENS, R. K. PIERENSSearch for more papers by this author K. E. CALDERBANK, K. E. CALDERBANKSearch for more papers by this authorR. K. PIERENS, R. K. PIERENSSearch for more papers by this author First published: February 22, 1977 https://doi.org/10.1002/chin.197708055AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Volume8, Issue8February 22, 1977 RelatedInformation

Polarisation and polarisability study of some chlorinated cyclodiene insecticides

The dipole moments and molar Kerr constants are reported for Aldrin, Dieldrin, Isodrin, Endrin, the keto-isomer of Endrin, Heptachlor, and Heptachlor cis-oxide as solutes in carbon tetrachloride. These data are used to obtain polarity and polarisability parameters for the structurally significant groups present.