National Toxicology Program

Selected toxicity information from HSDB, one of the National Library of Medicine's databases. ¹

Names (NTP)

• Dieldrin
• 3,4,5,6,9,9-HEXACHLORO-1TA,6ALPHA,7BETA,7ALPHA)-2,7:3,6-DIMETHANONAPHTH(2,3-B)OXIRENE (9CI)

Human Toxicity Excerpts

• ... Pesticide workers in a Shell plant in Holland ... had occupational exposure to dieldrin over periods of up to 12.3 yr with a mean of 6.6 yr. The average time that had elapsed from the end of exposure was 7.4 yr (maximum 16 yr). The average age was 47.4 yr. ... 223 long term workers were involved in this epidemiology study and no permanent adverse effects (including cancer) on workers health were observed. [USEPA; Ambient Water Quality Criteria Doc: Aldrin/Dieldrin p.C-58 (1980) EPA 440/5-80-019]**PEER REVIEWED**
  
• ... After repeated exposures /to dieldrin/ spraymen developed a syndrome indistinguishable from idiopathic epilepsy, except that it ceased when exposure was terminated. [NIOSH; Special Occupational Hazard Review: Aldrin/Dieldrin p.84 (1978) DHEW Pub. NIOSH 78-201]**PEER REVIEWED**
  
• ... Significantly higher C-reactive protein levels /were noted/ in the sera of workers chronically exposed to dieldrin and pentachlorophenol than in controls. Serum levels of gamma 2-globulin were associated with concn of dieldrin in the serum. [NIOSH; Special Occupational Hazard Review: Aldrin/Dieldrin p.93 (1978) DHEW Pub. NIOSH 78-201]**PEER REVIEWED**
  
• In a study of 5 male farmworkers exposed to a mixture of herbicides and pesticides including dieldrin, four were found to have suffered impotence after chronic exposure; sexual function recovered after termination of exposure. [NIOSH; Special Occupational Hazard Review: Aldrin/Dieldrin p.93 (1978) DHEW Pub. NIOSH 78-201]**PEER REVIEWED**
  
• ... Dieldrin, at concn as low as 25 ug/ml, was toxic to ... human kidney cell line B in vitro. [NIOSH; Special Occupational Hazard Review: Aldrin/Dieldrin p.81 (1978) DHEW Pub. NIOSH 78-201]**PEER REVIEWED**
  
• ... unscheduled DNA synthesis in SV40 transformed VA-4 human fibroblasts in vitro with and without an uninduced rat liver activating system using /dieldrin/ ... produces a significant incr in unsceduled DNA synthesis either with or without the activating system at all doses used. [USEPA; Ambient Water Quality Criteria Doc: Aldrin/Dieldrin p.C-44 (1980) EPA 440/5-80-019]**PEER REVIEWED**
  
• At 1, 10, and 30 ug/ml dieldrin caused chromosomal interchanges and rings in human lung cell cultures (WI-38 cells). Cytotoxic studies using WI-38 cells revealed dose-response and time-response relations to dieldrin. [NIOSH; Special Occupational Hazard Review: Aldrin/Dieldrin p.79 (1978) DHEW Pub. NIOSH 78-201]**PEER REVIEWED**
  
• SYMPTOMATOLOGY: (Onset of symptoms between 20 min and 12 hr after ingestion): 1. Malaise, headache, nausea, vomiting, dizziness, and tremors. 2. Clonic and tonic convulsions, sometimes without premonitory symptoms. 3. Convulsive episodes may alternate with periods of severe central nervous depression. Death from respiratory arrest may occur during coma, which commonly outlasts the convulsive phase and may persist for a few days. [Gosselin, R.E., R.P. Smith, H.C. Hodge. Clinical Toxicology of Commercial Products. 5th ed. Baltimore: Williams and Wilkins, 1984., p. III-144]**PEER REVIEWED**
  
• SYMPTOMATOLOGY: 4. During the acute phase, leukocytosis, rise in blood pressure, tachycardia, arrhythmias, metabolic acidosis, and fever have been described; Presumably they represent the consequences of hyperactivity of the sympathetic nervous system. 5. Disturbances of sleep, memory, and behavior may persist for several days or weeks after the acute phase of dieldrin poisoning. 6. Generalized cerebral dysrhythmia persisting for months, and both hematuria and albuminuria of about 2 weeks duration have been described in one aldrin poisoning in man. Transient hematuria occurred on the second day of an acute dieldrin poisoning. [Gosselin, R.E., R.P. Smith, H.C. Hodge. Clinical Toxicology of Commercial Products. 5th ed. Baltimore: Williams and Wilkins, 1984., p. III-144]**PEER REVIEWED**
  
• ... Ocular disturbance so far noted in human beings has been "blurred vision" of undetermined cause, & nystagmus accompanying incoordination & tremor. ... One case is reported of dense central scotomas 20 deg in diameter in both eyes with slight congestion of the nerveheads, in a man who had prolonged & recent intense exposure to a proprietary misture containing dieldrin ... in a wood preservative spray. Deterioration of vision occurred during 2 wk & did not recover in spite of corticosteroid treatment. Whether dieldrin itself was responsible could not be proved. ... A review & discussion of instances of dieldrin poisoning suggest that if dieldrin has serious effects on vision in human beings, this must be rare. [Grant, W.M. Toxicology of the Eye. 3rd ed. Springfield, IL: Charles C. Thomas Publisher, 1986., p. 332]**PEER REVIEWED**
  
• Thirteen volunteers were given dieldrin by mouth for 18 months; in 9 of them the daily dose ranged 10 to 211 ug. None showed evidence of ill health and results of clinical and lab investigations remained within the normal range and showed no significant change. The avg concn of dieldrin in fat was 156 times that in the blood. [Reynolds, J.E.F., Prasad, A.B. (eds.) Martindale-The Extra Pharmacopoeia. 28th ed. London: The Pharmaceutical Press, 1982., p. 836]**PEER REVIEWED**
  
• Vital status and cause of death were assessed for 232 of a group of 233 workers engaged in the manufacuturing and formulation of aldrin, dieldrin, endrin and (for a limited period) telodrin. This group is part of the total exposed population of more than 1000 workers and was selected for follow up on account of the high exposures in the initial years of manufacturing and formulation of the long exposure (mean 11 years) and observation (mean 24 years) periods. Total observed mortality was 25 versus 38 expected on the basis of the death statistics of the male Dutch population. Of the 9 cancer deaths, 3 were caused by lung cancer, while the remaining 6 were each of a different nature. Although in this group exposures have been high and exposure, as well as observation periods, were long enough for meaningful evaluation, this study revealed no indication of a specific carcinogenic activity of aldrin, dieldrin or endrin in manufacturing plant workers exposed to these products. [Ribbens PH; Int Arch Occup Environ Health (56) 2: 75-9 (1985)]**PEER REVIEWED**
  
• Studies of the carcinogenicity, mutagenicity and teratogenicity of insecticides in animals and humans are reviewed. ... Aldrin and dieldrin are of questionable carcinogenicity in animals but do not appear to be mutagenic in humans. [Sternberg SS; Int Encyclo Pharm Ther 113: 561-80 (1984)]**PEER REVIEWED**
  
• A study was conducted to determine whether men suffering from impaired fertility of unknown etiology exhibited increased blood levels of dieldrin. Dieldrin blood residues were measured in 29 infertile males and in 14 matched control subjects at a hospital in Jerusalem, Israel. The patients' ages ranged from 25 to 45 years. The patients exhibited one or more impaired semen characteristics such as decreased spermatozoa count, lower sperm motility, or a greater proportion of morphologically abnormal spermatozoa. The control group, matched by age and smoking habits, consisted of randomly selected patients with minor illnesses. Each of them had at least one child not older than two years of age. None of the subjects had a history of occupational exposure to organochlorine compounds. The dieldrin levels were measured by GC-ECD. The mean concentration of dieldrin in the infertile patients was 3.65 + or - 3.71 ng/g blood serum (range 0 to 15.9 ng/g) compared with 2.69 + or - 2.47 ng/g (range 0 to 7.1 ng/g) in the control group. This difference was not considered statistically significant. [Pines A et al; Arch Environ Contam Toxicol 16: 587-97 (1987)]**PEER REVIEWED**
  
• The lethal dose of dieldrin in man was estimated as 65 mg/kg body wt. ... Dieldrin was less ... toxic by ingestion as by skin absorption. ... Dermal rather than respiratory exposure was the major source of occupational poisoning in man. [Reynolds, J.E.F., Prasad, A.B. (eds.) Martindale-The Extra Pharmacopoeia. 28th ed. London: The Pharmaceutical Press, 1982., p. 836]**PEER REVIEWED**
  
• Dieldrin ... has caused numerous cases of chronic poisoning to workers who have sprayed the compound for several months. Characteristically there is headache, dizziness, and involuntary muscular movements. In severe cases there are epileptic convulsions with loss of consciousness. The only ocular disturbance so far noted in human beings has been blurred vision of undetermined cause, and nystagmus accompanying incoordination and tremor. [Grant, W.M. Toxicology of the Eye. 3rd ed. Springfield, IL: Charles C. Thomas Publisher, 1986., p. 332]**PEER REVIEWED**
  
• In exposed individuals manifesting serum concentrations of dieldrin, who had a range of 4-350 ppb, there was no evidence of hepatic injury ... . Hepatic enzyme activity levels were found to be normal in 233 pesticide applicators exposed occupationally to ... dieldrin ... for a period of 4-12 years. Studies have concluded that long term exposure to aldrin and dieldrin do not produce liver disease detectable by enzyme elevation or hepatic enzyme induction ... . [Sullivan, J.B. Jr., G.R. Krieger (eds.). Hazardous Materials Toxicology-Clinical Principles of Environmental Health. Baltimore, MD: Williams and Wilkins, 1992., p. 1045]**PEER REVIEWED**
  
• Dieldrin causes hypersensitivity and muscular fasciculations which may be followed by convulsive seizures and respective changes in electroencephalogram (EEG) patterns. Symptoms of intoxication include (acute) hyperirritability, convulsions, and/or coma sometimes accompanied by nausea, vomiting, and headache. Chronic intoxication may result in fainting muscle spasms, tremors, and loss of weight. ... Lethal dose for man /was estimated/ to be about 5 grams. [American Conference of Governmental Industrial Hygienists, Inc. Documentation of the Threshold Limit Values and Biological Exposure Indices. 6th ed. Volumes I, II, III. Cincinnati, OH: ACGIH, 1991., p. 456]**PEER REVIEWED**
  
• We investigated whether organochlorine exposure is associated with the incidence of infectious diseases in Inuit infants from Nunavik (Arctic Quebec, Canada). We compiled the number of infectious disease episodes during the first yr of life for 98 breast-fed & 73 bottle-fed infants. Concns of organochlorines were measured in early breast milk samples & used as surrogates to prenatal exposure levels. Immune system parameters were determined in venous blood samples collected from infants at 3, 7, & 12 months of age. Otitis media was the most frequent disease, with 80.0% of breast-fed & 81.3% of bottle-fed infants experiencing at least one episode during the first yr of life. During the second follow-up period, the risk of otitis media increased with prenatal exposure to p,p'-DDE, hexachlorobenzene, & dieldrin. The relative risk (RR) for 4- to 7-month-old infants in the highest tertile of p,p'-DDE exposure as compared to infants in the lowest tertile was 1.87 (95% confidence interval (CI), 1.07-3.26). The RR of otitis media over the entire first yr of life also increased with prenatal exposure to p,p'-DDE (RR, 1.52; CI, 1.05-2.22) & hexachlorobenzene (RR, 1.49; CI, 1.10-2.03). Furthermore, the RR of recurrent otitis media (: 3 episodes) increased with prenatal exposure to these cmpds. No clinically relevant differences were noted between breast-fed & bottle-fed infants with regard to immunologic parameters, prenatal organochlorine exposure was not associated with immunologic parameters. We conclude that prenatal organochlorine exposure could be a risk factor for acute otitis media in Inuit infants. [Dewailly E et al; Environmental Health Perspectives 108 (3): 205-11 (2000)]**PEER REVIEWED**
  
• Several organochlorinated pesticides including ... dieldrin have been reported to cause immune suppression ... in animals. ... We exposed Jurkat/, a human T-cell leukemic cell line,/ cells to varying concns of endosulfan for 0-48 hr & analyzed biochemical & molecular features characteristic of T-cell apoptosis. ... This study reports for the first time that endosulfan can induce apoptosis in a human T-cell leukemic cell line which may have direct relevance to loss of T cells & thymocytes in vivo. Furthermore, our data strongly support a role of mitochondrial dysfunction & oxidative stress in endosulfan toxicity. [Kannan K et al.; Mol Cell Biochem 205 (1-2): 53-66 (2000)]**PEER REVIEWED**
  

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Non-Human Toxicity Excerpts

• MUTAGENICITY: MUTATION RESEARCH 87: 81 (1981). CHINESE HAMSTER LUNG (V79) CELLS IN CULTURE - GENE MUTATION, OUABAIN LOCUS STUDIES: POSITIVE. [GENE-TOX Program: Current Status of Bioassay in Genetic Toxicology. U.S. Environmental Protection Agency, Washington, DC. Office of Toxic Substances and Pesticides. (For program information, contact Environmental Mutagen Information Center, Oak Ridge National Laboratory, Post Office Box Y, Oak Ridge, Tennessee 37830. Telephone (615) 574-7871), p. ]**PEER REVIEWED**
  
• DIELDRIN FED TO MICE (CF1) FOR 2 YR PRODUCED DOSAGE-DEPENDENT INCIDENCE OF HEPATOMAS. IN MALES INCIDENCES WERE: CONTROLS, 7%; ON 0.1 PPM ... 21%; ON 1 PPM ... 28%; & ON 10 PPM ... 53%. IN FEMALES, INCIDENCES WERE: CONTROLS, 4%; ON 0.1 PPM ... 30%; ON 1 PPM ... 42%; & ON 10 PPM ... 62%. [National Research Council. Drinking Water & Health Volume 1. Washington, DC: National Academy Press, 1977., p. 565]**PEER REVIEWED**
  
• SINGLE ORAL DOSES OF APPROX 1/2 ... LD50 DOSES WERE GIVEN ON DAYS 7, 8 OR 9 /OF GESTATION/ IN HAMSTER & ON DAY 9 /OF GESTATION/ IN MOUSE. SIGNIFICANT NUMBER OF DEFECTS ... PRODUCED IN BOTH SPECIES ON ALL DAYS TREATED. MALFORMATIONS IN BOTH SPECIES WERE OPEN EYES, WEBBED FEET & CLEFT PALATE. /DIELDRIN WAS 1 OF PESTICIDES ADMIN/ [Shepard, T. H. Catalog of Teratogenic Agents. 3rd ed. Baltimore, MD.: Johns Hopkins University Press, 1980., p. 87]**PEER REVIEWED**
  
• Dieldrin: ... was admin orally to pregnant sows during periods in the last month of gestation. Doses up to 15 mg/kg produced no fetal changes but the cmpd was detected in the fetal tissues. [Shepard, T.H. Catalog of Teratogenic Agents. 5th ed. Baltimore, MD: The Johns Hopkins University Press, 1986., p. 197]**PEER REVIEWED**
  
• RACCOONS FED DIELDRIN @ 2 & 6 PPM IN DIET PRODUCED 20.0 & 20.2%, RESPECTIVELY AS MANY YOUNG AS DID UNTREATED CONTROLS. LITTER SIZE ... REDUCED. IN FURTHER STUDY, RACCOONS FED DIELDRIN @ 2 PPM HAD ABNORMAL ESTROUS CYCLE, REDUCED OVULATION RATE, REDN OF PREGNANCY TO 25-30% OF THAT OF CONTROLS, INCR RESORPTION OF EMBRYOS ... RACCONS FED ... 2 PPM ... DIELDRIN ... INFLUENCED SPERMATOGENSIS, SPERM QUALITY, & FERTILITY ADVERSELY IN MALE RACCONS. [National Research Council. Drinking Water & Health Volume 1. Washington, DC: National Academy Press, 1977., p. 567]**PEER REVIEWED**
  
• ACUTE SYMPTOMS: TAIL FEATHERS SPREAD & POINTED EITHER UPWARD OR DOWNWARD, HYPEREXCITABILITY, JERKINESS IN GAIT, ATAXIA, DYSPNEA, MYASTHENIA, FLUFFED FEATHERS, IMMOBILITY, TERMINAL WING-BEAT CONVULSIONS OR OPISTHOTONOS. MORTALITIES USUALLY OCCURRED 1-9 DAYS FOLLOWING TREATMENT. /BIRDS; ORAL/ [U.S. Department of the Interior, Fish and Wildlife Service. Handbook of Toxicity of Pesticides to Wildlife. Resource Publication 153. Washington, DC: U.S. Government Printing Office, 1984., p. 31]**PEER REVIEWED**
  
• Fed to male & /female/ Osborne-mendel rats at dietary concn of 29 and 65 ppm ... all concn ... time weighed avg doses. ... Significant difference in combined incidence of adrenal cortical adenoma or carcinoma in low dose females and pooled controls: "Although ... tumor ... found ... is not clearly assoc with treatment ... ." /NCI/ [Clayton, G.D., F.E. Clayton (eds.) Patty's Industrial Hygiene and Toxicology. Volumes 2A, 2B, 2C, 2D, 2E, 2F: Toxicology. 4th ed. New York, NY: John Wiley & Sons Inc., 1993-1994., p. 1530-31]**PEER REVIEWED**
  
• Mutagenic potential ... investigated through direct bacterial tests with and without microsomal activation, host-mediated assay, blood and urine analysis ... micronuclei test, metaphase analysis, and dominant lethal test. Concn ... 0.08, 0.8, & 8 mg/kg/mouse. ... Evaluation of data indicated that dieldrin was negative in all 4 animal tests. [Clayton, G.D., F.E. Clayton (eds.) Patty's Industrial Hygiene and Toxicology. Volumes 2A, 2B, 2C, 2D, 2E, 2F: Toxicology. 4th ed. New York, NY: John Wiley & Sons Inc., 1993-1994., p. 1531-32]**PEER REVIEWED**
  
• In ... teratogenic study, dieldrin and photodieldrin ... admin in doses of 1.5, 3.0, & 6.0 mg/kg/day on days 7-16 of gestation, to DCI mice and CD rats. In mice, highest dose produced incr percentage of supernumerary ribs and decr in number of caudal ossification centers. No changes were observed in rats. [Clayton, G.D., F.E. Clayton (eds.) Patty's Industrial Hygiene and Toxicology. Volumes 2A, 2B, 2C, 2D, 2E, 2F: Toxicology. 4th ed. New York, NY: John Wiley & Sons Inc., 1993-1994., p. 1527]**PEER REVIEWED**
  
• ... Various dietary concn of dieldrin /fed/ to female Swiss-Vancouver mice ... /caused/ dose-related hepatomegaly, incr in cytochrome p450 and microsomal protein, and decr in pentobarbital sleeping time. ... Reported decr in liver glycogen and incr in liver cholesterol in rabbits treated with dieldrin. [Clayton, G.D., F.E. Clayton (eds.) Patty's Industrial Hygiene and Toxicology. Volumes 2A, 2B, 2C, 2D, 2E, 2F: Toxicology. 4th ed. New York, NY: John Wiley & Sons Inc., 1993-1994., p. 1525]**PEER REVIEWED**
  
• ... Significant effects were found in /Swiss Mice/ 1st & 2nd generations and their offspring after feeding ... 3 and 10 ppm ... histological exam ... revealed changes in livers ... and in kidneys, lungs, and brains ... . [Clayton, G.D., F.E. Clayton (eds.) Patty's Industrial Hygiene and Toxicology. Volumes 2A, 2B, 2C, 2D, 2E, 2F: Toxicology. 4th ed. New York, NY: John Wiley & Sons Inc., 1993-1994., p. 1526]**PEER REVIEWED**
  
• 3-18 WK DIETARY ADMIN TO MICE. @ 18 WK SIGNIFICANT INCR IN SPONTANEOUS CELL SPREADING OF POYLMORPHONUCLEAR NEUTROPHILS BUT NOT MACROPHAGES. WITH DECR IN SERUM FIBRONECTIN WAS AN INCR SUSCEPTIBILITY TO TUMOR CELLS. [LOOSE ET AL; BIOL RELEVANCE IMMUNE SUPPR INDUCED GENET, THER ENVIRON FACTORS, (PAP WORKSHOP) 259-74 (1981)]**PEER REVIEWED**
  
• IN RHESUS MONKEYS ADMIN SINGLE ORAL DOSE OF DIELDRIN (20 MG/KG), THERE WAS AN INCR ACCUM OF LIPIDS AFTER 24 HR, PARTICULARLY TRIACYLGLYCEROLS IN ADIPOSE TISSUE, LIVER & KIDNEY. LEVEL IN THE PLASMA DID NOT CHANGE. [AGARWAL ET AL; TOXICOL APPL PHARMACOL 58 (1): 100-4 (1981)]**PEER REVIEWED**
  
• ORAL ADMIN OF A SINGLE DOSE (20 MG/KG) TO RHESUS MONKEYS GREATLY INCR THE INTAKE OF GLUCOSE & THE ACTIVITIES OF BRUSH BORDER SUCRASE, LACTASE, MALTASE & ALKALINE PHOSPHATASE IN INTESTINE COMPARED TO CONTROLS. [MAHMOOD ET AL; CHEM BIOL INTERACT 37 (1-2): 165-70 (1981)]**PEER REVIEWED**
  
• IN RAT DIELDRIN CAN EVOKE PROGRESSIVE INCR IN SEVERITY OF CONVULSIVE RESPONSES (KINDLING) DURING REPETITIVE EXPOSURES THAT CANNOT BE ATTRIBUTED TO SIMPLE ACCUM OF DIELDRIN IN THE BRAIN. CHRONIC EXPOSURE FACILITATES KINDLING PRODUCED BY DAILY ELECTRICAL STIMULATION OF AMYGDALA. [JOY ET AL; NEUROBEHAV TOXICOL 2 (2): 117-24 (1980)]**PEER REVIEWED**
  
• ... Lifetime feeding studies /were conducted with/ Syrian golden hamsters. ... Groups of nearly equal size (ie 32-41 per group) of male & female hamsters were fed a diet containing 0, 20, 60, or 80 mg/kg for up to 120 wk at which time the remaining survivors were killed. While there was no decr in survival at 50 wk, the numbers of females remaining at 70 wk was one-half or less than that of the males. At 90 wk the survival rate was about 10% for all groups except the males of the 180 mg/kg level which had 32% survivors. Both males & females at the low and high doses demonstrated a marked retardation of growth ... There was no significant difference between the % of control animals with tumors & the treated animals with tumors. However, in the treated groups, /the number of tumors per animal was incr over that of controls. Although there was an incr in the number of animals with adrenal tumors, especially males, ... this was not statistically significant. In the animals receiving the high dose of dieldrin, there was one male & one female which had hepatomas. It was also noted ... that there was a dose-related incr in the incidence of hepatic cell hypertrophy in the dieldrin-treated hamsters. [USEPA; Ambient Water Quality Criteria Doc: Aldrin/Dieldrin p.C-55 (1980) EPA 440/5-80-019]**PEER REVIEWED**
  
• Mallory bodies were noted in hepatic tumors following admin for up to 85 wk of a diet containing 10 ppm dieldrin to 50 C3H/He and 62 C57BL/6J6C3F1 male mice. Mallory bodies were seen in 15 of 28 (54%) mice which developed benign hepatic tumors and 33 of 45 (75%) mice with hepatocellular carcinoma, but in only 3 of 39 (8%) mice without hepatic tumors. In mice with tumors the mallory bodies were predominately confined to tumor tissue. ... /They/ were not observed in hepatic tumors of 67 C57BL/6J, 49 C3H/He, or 81 B6C3F1 mice given 12 ug diethylnitrosamine ip on days 0, 3, 9, and 15. ... One control had a tumor with a mallory body. [Meierhenry EF et al; Hepatology 3 (1): 90-5 (1983)]**PEER REVIEWED**
  
• Groups of 10 /white-tailed/ deer & their progeny were given dieldrin at 5 or 25 ppm /for 3 yr/. No signs of overt intoxication were observed, & 9 of 10 adult deer in each group survived the 3 yr. Growth was slower & remained reduced in dieldrin-exposed females that were immature when the study began. Hematologic values & serum protein concn were not significantly related to treatment. Liver-to-body weight ratios were significantly larger in deer given dieldrin at 25 ppm; pituitary glands were smaller & thyroids were larger in deer fed dieldrin. [NIOSH; Special Occupational Hazard Review: Aldrin/Dieldrin p.37 (1978) DHEW Pub. NIOSH 78-201]**PEER REVIEWED**
  
• Morphologic changes & an incr in SER & atypical mitochondria /were observed/ in adult male rats fed technical grade dieldrin at 50 or 100 ppm for 8 wk. [NIOSH; Special Occupational Hazard Review: Aldrin/Dieldrin p.39 (1978) DHEW Pub. NIOSH 78-201]**PEER REVIEWED**
  
• Single doses of dieldrin caused a marked proliferation of smooth endoplasmic reticulum in the liver of rats given 8 mg/kg and in dogs given 2 mg/kg, but caused less marked effects in mice given 0.16-7.5 mg/kg. [NIOSH; Special Occupational Hazard Review: Aldrin/Dieldrin p.39 (1978) DHEW Pub. NIOSH 78-201]**PEER REVIEWED**
  
• ... purified dieldrin /was admin/ at concn between 0.08 & 40 ppm in the diet to Wistar rats for up to 2 yr ... Nonspecific neural lesions, cranial edema, convulsions, & dieldrin residues in the brain /were reported/ in most exposed rats. ... Cranial edema was observed at 0.63 ppm, & cerebral, cerebellar, brainstem, & vascular lesions were noted at all dietary levels. Dieldrin residue levels of 9-11 ppm in the brain were assoc with convulsions. [NIOSH; Special Occupational Hazard Review: Aldrin/Dieldrin p.44 (1978) DHEW Pub. NIOSH 78-201]**PEER REVIEWED**
  
• In 39 to 140 day old female Wistar rats fed dieldrin at 2.5-10.0 ppm in the diet /in a reproductive toxicity study/. Parental mortality /& reduced fecundity was noted at 10 ppm/. Proliferation of reticuloendothelial components & pancreatic ductal cells /were noted/. Fibrinoid degeneration, arteritis, endothelial proliferation, & perivascular edema were observed in small to medium sized arteries. /Convulsions in pups was observed at 2.5 ppm/. [NIOSH; Special Occupational Hazard Review: Aldrin/Dieldrin p.46 (1978) DHEW Pub. NIOSH 78-201]**PEER REVIEWED**
  
• Dieldrin at 1, 2, or 4 mg/kg/day produced hyperplastic goiters in the thyroids of pigeons. ... Visual exam indicated that the thyroids were significantly enlarged & microscopic exam revealed small follicles with decr amount of colloid, epithelial hyperplasia, & vascular congestion. [NIOSH; Special Occupational Hazard Review: Aldrin/Dieldrin p.46-47 (1978) DHEW Pub. NIOSH 78-201]**PEER REVIEWED**
  
• Dieldrin: produces changes in the levels of serum luteinizing hormone. Levels of luteinizing hormone were not affected when the rats were fed dieldrin at 0.7 ppm. At 6.2 ppm, dieldrin produced significant elevations in serum luteinizing hormone. Even in castrated rats, dieldrin (6.2 ppm) caused an incr in the serum levels of this gonadotropin. Dieldrin also caused a slight decr in the ratio of body weight to pituitary gland weight & a small incr in the ratio of bw to prostate gland weight. [NIOSH; Special Occupational Hazard Review: Aldrin/Dieldrin p.54 (1978) DHEW Pub. NIOSH 78-201]**PEER REVIEWED**
  
• 1,500 CF1 mice /were/ segregated into groups containing the following numbers of animals of each sex: 300, 0.01 ppm dieldrin (control); 125, 0.1 ppm; 125, 1 ppm; 200, 10 ppm. At 10 ppm from 9 months onward palpable abdominal masses were detected. 50% of the mice fed dieldrin at 10 ppm were dead at 15 months and 50% in the other groups were at 20 months. Statistically significant and dose-related increases in liver tumors occurred in dieldrin-exposed mice in both sexes ... . Liver tumors included nodular growths of solid cords of parenchymal cells and papilliform and adenoid growths with cells proliferating in confluent sheets with necrosis and incr mitoses. Lung metastases were observed in animals with liver tumors that had the papilliform and adenoid type growth in 12/138 animals. Incidences of pulmonary adenomas and pulmonary carcinomas in males and females exposed to dieldrin at 0.1 and 1 ppm were incr above those in controls. Differences were statistically significant in females. [Walker AIT et al; Food Cosmet Toxicol 11: 415-32 (1972) NIOSH; Special Occupational Hazard Review: Aldrin/Dieldrin p.60 (1978) DHEW Pub. NIOSH 78-201]**PEER REVIEWED**
  
• ... The effects of exposure to dieldrin at 10 ppm were compared in CF1 mice, LACG mice, & in hybrids of the two strains. Forty mice of each sex were used in each treatment group, with groups of 60 controls. Age-adjusted incidence of liver tumors was significantly incr in all six treated groups. The incidence of lung tumors also was incr in all six treated groups, although not significantly so in any one considered alone. However, the incidence of other tumors was significantly incr in treated female CF1 mice. [NIOSH; Special Occupational Hazard Review: Aldrin/Dieldrin p.66-67 (1978) DHEW Pub. NIOSH 78-201]**PEER REVIEWED**
  
• Dieldrin was: neg for mutagenicity in recombination assays with Bacillus subtilis strains H17 Rec+ and M45 Rec-. /It was also/ neg for four strains of Salmonella typhimurium /TA 1535, TA 1536, TA 1537, & TA 1538/ & in two tryptophaneless strains of E coli ... . [NIOSH; Special Occupational Hazard Review: Aldrin/Dieldrin p.79 (1978) DHEW Pub. NIOSH 78-201]**PEER REVIEWED**
  
• ... recrystallized dieldrin caused chromosome damage in bone marrow cells of mice in vivo & in human embryonic cells in vitro. Single ip injections of dieldrin at 1, 30, or 50 mg/kg into STS mice caused pronounced mitotic inhibition & produced twofold to sixfold incr in chromosome abnormalities, primarily breaks & fragments in bone marrow cells; these changes were statistically significant at dose of 1 mg/kg and above. [NIOSH; Special Occupational Hazard Review: Aldrin/Dieldrin p.79 (1978) DHEW Pub. NIOSH 78-201]**PEER REVIEWED**
  
• Recrystallized dieldrin inhibited incorporation of amino acid precursors of DNA, RNA, & protein into Ehrlich ascites tumor cells in vitro. ... Daily injections of dieldrin at 1.5 mg/kg for 5 days into mice inhibited the growth of Ehrlich ascites tumor cells in vivo. [NIOSH; Special Occupational Hazard Review: Aldrin/Dieldrin p.81 (1978) DHEW Pub. NIOSH 78-201]**PEER REVIEWED**
  
• Dieldrin: gave negative results with gene conversion in Saccharomyces cerevisae, back mutation in Serratia marcescens, forward mutation in E coli and forward mutation to streptomycin resistance in E coli. [USEPA; Ambient Water Quality Criteria Doc: Aldrin/Dieldrin p.C-39 (1980) EPA 440/5-80-019]**PEER REVIEWED**
  
• Experimental feeding of dieldrin to rabbits at 60 to 110 mg/kg weekly for 12 wk caused convulsions and apparent "blindness". ... In mice, retinal photoreceptor electrical responses have been disturbed by 20 mg intraperitoneally. [Grant, W.M. Toxicology of the Eye. 3rd ed. Springfield, IL: Charles C. Thomas Publisher, 1986., p. 332]**PEER REVIEWED**
  
• Fish are highly susceptible to dieldrin and pollution of streams must be avoided. Birds are also susceptible and dressed seeds may be regarded as a source of poisoning ... dogs and other animals feeding on the carcasses of poisoned birds may also be affected. [Reynolds, J.E.F., Prasad, A.B. (eds.) Martindale-The Extra Pharmacopoeia. 28th ed. London: The Pharmaceutical Press, 1982., p. 836]**PEER REVIEWED**
  
• Animals were exposed to 0.1, 1, 5, or 10 ppm dieldrin in C-1000 diet. Animals were killed after 1.85, 3, 6, 9, and 14 months of treatment. A linear incr was noted in the proportion of octaploid nuclei over the observaiton period. Dieldrin enhancement of polyploidization was proportional to dietary concn and independent of duration of exposure. A virtually constant ploidy status is suggested at the time of liver tumor formation. ... Tumor formation appears imminent at a constant biological age of mouse liver, and tumor promoters may operate by advancing the biological age of their target organ during the initial phases of treatment. [van Ravenzwaay B et al; Carcinogenesis 8 (2): 265-69 (1987)]**PEER REVIEWED**
  
• The effect of single, sublethal ip injection of dieldrin on the primary antibody response to thymodependent (sheep red blood cells, SRBC) and T-cell-independent (lipopolysaccharide, LPS) antigens were investigated in inbred C57B1/6 mice. Time course studies showed significant suppression of the anti-SRBC IgM and anti-LPS IgM response at 7-24 days and at 4-14 days, respectively, after exposure to 0.6 LD50 of dieldrin. The anti-SRBC IgG response was also suppressed by dieldrin exposure, however, maximal suppressory effect was found at 48 days after the pesticide exposure. Similar patterns of the dieldrin-induced suppression of the primary IgM response to the thymodependent and T cell- independent antigens, in addition to the overall control of cytotoxicity of lymphoid cell populations, suggest rather dysfunction of cellular cooperation during the inductory phase of the immune humoral response. [Bernier J et al; Toxicol Lett 35 (2-3): 231-40 (1987)]**PEER REVIEWED**
  
• Rats were given acute doses (0, 0.5, 1.5, 4.5 mg/kg) of ... dieldrin and subsequently exposed to a series of 40 escapable shocks, identical inescapable shocks, or no shock in an operant chamber. Eight hours later, the subjects were re-exposed in a shuttlebox to footshock which was escapable upon performance of an FR-2 shuttle response. Escape deficits which were related in magnitude to the size of the dieldrin dose were found in the inescapable shock group but not in the escapable shock or no shock groups. The data suggest that experience with the lack of control over stress is critical in determining the behavioral effects of the agent and that the behavioral effects caused by uncontrollable stress may be exacerbated by concurrent exposure to such compounds. [Carlson JN et al; Psychopharmacology 91 (1): 122-6 (1987)]**PEER REVIEWED**
  
• Dieldrin (5 m uM) increased the electron opacity of the cytoplasm and nucleoplasm of cockroach glial cells without inducing such a change in the fine structure of perineurial cells. Mitochondria in nerve cell bodies and neuropile of dieldrin-treated ganglia were swollen with broken cristae and devoid of normal morphological appearance. Dieldrin treatment also caused notable depletion of synaptic vesicles from presynaptic terminals in the neuropile. Depleted terminals accumulated membranous residual bodies and lysosomes indicative of insecticide-induced neuronal deterioration. These ultrastructural alterations were prevented by pretreatment of ganglia with 10 mM Mg 2+, suggesting that the action of dieldrin upon the ganglion was mediated by an increased Ca flux. [Singh GJ; Singh B; Pestic Biochem Physiol 21 (1): 102-26 (1984)]**PEER REVIEWED**
  
• Dieldrin is the only ... /cyclodiene insecticide/ that has produced notable loss of appetite or even complete refusal of food in animals. [Hayes, W.J., Jr., E.R. Laws, Jr., (eds.). Handbook of Pesticide Toxicology. Volume 2. Classes of Pesticides. New York, NY: Academic Press, Inc., 1991., p. 828]**PEER REVIEWED**
  
• Young calves were poisoned by 10 mg/kg of dieldrin given orally, horses and sheep by 25 mg/kg and young pigs by 50 mg/kg. In the diet, 50-100 ppm may kill deer when fed over about a month. In dogs, gross toxic effects were shown by animals receiving more than 0.5 mg/kg daily of dieldrin. Dieldrin is rapidly absorbed through unbroken skin even in powder form. It has poisoned young calves when it has been applied dermally at a concentration of 0.25%, and it has poisoned cattle at 2%, young lamb at 3% and sheep and goats at 4%. Lower concentrations were not toxic, and horses tolerated 1% sprays. [Humphreys, D.J. Veterinary Toxicology. 3rd ed. London, England: Bailliere Tindell, 1988., p. 150]**PEER REVIEWED**
  
• In mice, retinal photoreceptor electrical responses have been disturbed by 20 mg intraperitoneally. [Grant, W.M. Toxicology of the Eye. 3rd ed. Springfield, IL: Charles C. Thomas Publisher, 1986., p. 332]**PEER REVIEWED**
  
• Experimental feeding of dieldrin to rabbits at 60 to 110 mg/kg weekly for 12 weeks caused convulsions and apparent blindness. The nature of this blindness has not been determined. [Grant, W.M. Toxicology of the Eye. 3rd ed. Springfield, IL: Charles C. Thomas Publisher, 1986., p. 332]**PEER REVIEWED**
  
• The promoting activity of dieldrin on the induction of hyperplastic (neoplastic) liver nodules /was studied/ using a short term test system. F344 rats received a single dose (200 mg/kg body weight) of N-nitrosodiethylamine, and 2 weeks later, were treated for 6 weeks with dieldrin in the diet at a concentration of 100 mg/kg. Dieldrin had a weak promoting potential in this test system. [WHO; Environ Health Criteria 91; Aldrin and Dieldrin p.198 (1989)]**PEER REVIEWED**
  
• Macrophages from mice fed 50 mg dieldrin/kg diet had a marked impairment in antigen processing. The effect was statistically significant in Kupffer cells at 50 mg diet, in alveolar and splenic macrophages at 0.5, 5 and 50 mg/kg diet, and in peritoneal macrophages at 5 and 50 mg/kg diet. There was an impairment of in vivo phagocytic clearance in mice receiving 5 or 50 mg/kg diet for 8 weeks but not at 0.5 mg/kg diet. This was related to a decrease in serum fibronectin. Tumor cell killing after challenge with EL-4, P388, or mKSA tumor cells was significantly impaired in mice fed either 1 or 5 mg dieldrin/kg diet. The mean survival time after challenge with FL-4 was reduced by 3 weeks, and with the P388 or mKSA tumor cells impairment was observed after 3 or 18 weeks, respectively. There was not alteration in the oxygen uptake by isolated macrophages either at rest or during phagocytosis, and no effect on phagocytic active or opacity or on chemotaxis in vitro was observed. [WHO; Environ Health Criteria 91; Aldrin and Dieldrin p.212 (1989)]**PEER REVIEWED**
  
• Dieldrin caused immunosuppression in mice. Levels of 1 or 5 mg dieldrin/kg diet were fed to BALB/c mice for 3.5 or 10 wk, & the mice were challenged intradermally with Leischmania tropica. Dieldrin acted synergistically on lethality in a dose and time related manner, indicating an effect on host mechanisms. It also resulted in decr antibody formation to PVP, a T-independent antigen (direct splenic plague assay). The mitogenic response of cultured T cells to phytohaemagglutinin in dosed mice was depressed. Mitomycin C & anti-Thy-1, the mitogenic response. When splenic T cells from treated mice were mixed with T cells from control mice, there was inhibition of phytohaemagglutinin mitogenesis. The data indicated an active cell-mediated suppressor. A soluble macrophage factor from the hepatic Kupffer cells (but not from alveolar or peritoneal macrophages) suppressed the T cell response to phytohaemagglutinin. It was concluded that admin of 5 mg dieldrin/kg diet to mice for 10 wk caused a profound impairment of macrophage antigen processing. [WHO; Environ Health Criteria 91; Aldrin and Dieldrin p.212 (1989)]**PEER REVIEWED**
  
• Susceptibility of early-life stages of rainbow trout /todieldrin was studied/. The test was performed with fertilized eggs before & after water hardening, & with early eye point eggs, late eye point eggs, sac fry, & early fry. No mortality was found in the different early-life stages using concentrations greater than aqueous solubility (> 10 mg/l), except for the early fry where a very low 96 hr LC50 of 0.003 mg/l was found. [WHO; Environ Health Criteria 91; Aldrin and Dieldrin p.166 (1989)]**PEER REVIEWED**
  
• The in vitro exposure of toad embryo tissue (Bufo arenarum) to dieldrin (1X10-5 mole/l) produced an inhibition of acetyl & butyryl cholinesterase activity. In in vivo studies with open-mouth stage embyros, dieldrin produced acetyl cholinesterase inhibition at 0.5X10-6 mole/l. Furthermore, hyperactivity in swimming larvae was observed. [WHO; Environ Health Criteria 91; Aldrin and Dieldrin p.167 (1987)]**PEER REVIEWED**
  
• The decline of populations of peregrine falcon & sparrow hawk in the United Kingdom ... was assoc with the death of breeding adults. This was attributed to dieldrin usage, which correlated well with the decline. [WHO; Environ Health Criteria 91; Aldrin and Dieldrin p.183 (1989)]**PEER REVIEWED**
  
• Groups of weanling male C3H/HE mice were fed a diet containing 10 mg dieldrin/kg diet until an age of 57 wk & then were either admin a control diet (12 mice) or continued on the dieldrin diet (11 mice) for another 10 wk. A third group served as an untreated control group (21 mice). Laparatomies were performed & biopsy specimens taken when about 30% of the mice in each dieldrin treated group had tumors. Further biopsy samples were taken approx 10 wk later. Tumors were observed at the first laparotomy in 6/21 control & 14/23 dieldrin treated animals. At the second laparotomy, adenomas were seen in some animals in which there had been no tumor at the first laparotomy. In the animals in the continuous dieldrin treatment group, there was histological progression from adenoma to hepatocellular carcinoma. Additional hepatocellular carcinomas were observed in some animals autopsied at 2 yr of age. A strong tendency to tumor progression was found in both treated & control mice. [WHO; Environ Health Criteria 91; Aldrin and Dieldrin p.194 (1987)]**PEER REVIEWED**
  
• When groups of male albino rats were fed diets equivalent to 2 mg/kg bw for 6 mo, the alkaline phosphatase, SGPT, SGOT, & LD-hydrogenase activities in the serum were incr after 6 months. The urea content decr after 3 mo, & some other parameters were also changed. The growth of the animals was considerably inhibited. [WHO; Environ Health Criteria 91; Aldrin and Dieldrin p.188 (1989)]**PEER REVIEWED**
  
• Dieldrin decr antibody forming cell responses and incr susceptibility to viral infection in mice. /From table/ [Amdur, M.O., J. Doull, C.D. Klaasen (eds). Casarett and Doull's Toxicology. 4th ed. New York, NY: Pergamon Press, 1991., p. 314]**PEER REVIEWED**
  
• Aldrin & dieldrin & other cyclodiens inhibit the gamma amino butyric acid-induced chloride ion uptake into skeletal muscles & the binding of tritiated dihydropicrotoxinin (anion channel probe) to the membrane. This results in central nervous system excitation & convulsions due to the blocking of gamma amino butyric acid transmitters. [WHO; Environ Health Criteria 91; Aldrin ad Dieldrin p.3.217 (1989)]**PEER REVIEWED**
  
• Dieldrin did not induce dominant lethal mutations in mice or chromosomal aberrations in bone-marrow cells of Chinese hamsters treated in vivi. It induced unscheduled DNA synthesis in transformed human fibroblasts but not in rat hepatocytes; it didn't induce single strand breaks in Chinese hamster V79 cells. Dieldrin inhibited intercellular communication in human and rodent cell systems. It did not induce sex-linked recessive lethal mutations in Drosophila, was not mutagenic to bacteria and did not induce breakage of plasmid DNA. [IARC. Monographs on the Evaluation of the Carcinogenic Risk of Chemicals to Man. Geneva: World Health Organization, International Agency for Research on Cancer, 1972-PRESENT. (Multivolume work)., p. S7 196 (1987)]**PEER REVIEWED**
  
• According to a Canadian study, exposure to certain pesticides may weaken the immune system, resulting in incr susceptibility to infection. ... dieldrin ... may damage the mammalian immune system. [Kavaler, A.R. (ed.). Chemical Marketing Reporter. New York, NY: Schnell Publishing Co., Inc., 1984, p. V230(7) 4]**PEER REVIEWED**
  
• Two cases of dieldrin-type poisoning in dogs have been reported. The animals had probably been fed on wood pigeons killed by dressed seed. The clinical and analytical data from 40 cases suspected dieldrin poisoning in sheepdogs /was reported/. The syndrome was characterized by anorexia, emaciation and involvement of the nervous system. The method of exposure was unknown except in four cases, but the time factor suggested the implication of sheep-deeps, sprays, or dusts. A similar syndrome in puppies has been described. [Humphreys, D.J. Veterinary Toxicology. 3rd ed. London, England: Bailliere Tindell, 1988., p. 150]**PEER REVIEWED**
  
• Poisoning in cats, due to exposure to a wooden floor which had been treated six weeks previously with an anti-woodworm preparation containing dieldrin, has been reported. [Humphreys, D.J. Veterinary Toxicology. 3rd ed. London, England: Bailliere Tindell, 1988., p. 150]**PEER REVIEWED**
  
• Dieldrin is not recommended for use on livestock. Residues limit its application, and it is one of the most toxic chlorinated hydrocarbon insecticides. Young dairy calves are poisoned by 8.8 mg/kg body wt, PO, but tolerate 4.4 mg/kg, while adult cattle tolerate 8.8 mg/kg and are poisoned by 22 mg/kg. Pigs tolerate 22 mg/kg and are poisoned by 44 mg/kg. Horses are poisoned by 22 mg/kg. Because of its effectiveness against insect pests on crops and pasture and consequent low dosage per acre, dieldrin is not likely to poison livestock grazing the treated areas. [Aiello, S.E. (ed). The Merck Veterinary Manual. 8th ed. Merck & Co., Inc., National Publishing Inc., Philadelphia, PA. 1998., p. 2063]**PEER REVIEWED**
  
• A series of experiments on mice .../involving/ ... continuous feeding of recrystallized (>99% pure) dieldrin was found to produce liver-cell tumors, while the incidence of tumors at other sites was either unaffected or decreased in relation to the shorter life span of animals with liver tumors. [IARC. Monographs on the Evaluation of the Carcinogenic Risk of Chemicals to Man. Geneva: World Health Organization, International Agency for Research on Cancer, 1972-PRESENT. (Multivolume work)., p. V5 134 (1974)]**PEER REVIEWED**
  
• Although benign, uterine leiomyomas occur with high frequency & significant morbidity in reproductive-age women, & they present a significant health problem. Leiomyomas develop in the uterine myometrium & are sensitive to ovarian hormones, making them potential target sites for endocrine disruptors. Here we utilize cell lines derived from rat uterine leiomyomas to determine if a panel of 7 organochlorine pesticides have potential agonist activity in myometrial cells using cellular & molecular in vitro assays. The organochlorine pesticides investigated have been previously characterized as having agonist activity in other hormonally responsive tissues, but their effects have not been studied in uterine myometrial cells. In Eker rat leiomyoma-derived cells, HPTE, kepone, & the alpha isomer of endosulfan stimulated proliferation, an effect dampened by the antiestrogen ICI 182,780. In addition, these cmpds stimulated transcription of the vitellogenin estrogen-response element via the ER in a transcriptional reporter gene assay & induced the expression of an endogenous estrogen-responsive gene, the progesterone receptor (PR). This contrasted with the agonist profile of methoxychlor, dieldrin, toxaphene, & endosulfan-beta. These cmpds, unable to stimulate proliferation of uterine leiomyoma cells, did exhibit agonistic activity in these cells at the transcriptional level in the estrogen-sensitive reporter gene assay, & they were also able to upregulate PR message. These data demonstrate that organochlorine pesticides act as estrogen receptor agonists in Eker rat uterine myometrial cells, & they indicate a need for further investigation of the potential tissue-specific agonist activity of these pesticides & their role in the pathogenesis of uterine leiomyoma. [Hodges LC et al.; Toxicol Sci 54 (2): 355-364 (2000)]**PEER REVIEWED**
  
• ... In the last 5 yr, several environmental chemicals have been added to the list of xenoestrogens, including the pesticides toxaphene, dieldrin & endosulphan ... . [Olea Net al.; Eur J Cancer Prev 7 (1): S17-23 (1998)]**PEER REVIEWED**
  

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Human Toxicity Values

• None found

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Non-Human Toxicity Values

• LD50 Rat oral 38.3 mg/kg [NIOSH; Special Occupational Hazard Review: 78-201]**PEER REVIEWED**
  
• LD50 Sheep oral 50-75 mg/kg [NIOSH; Special Occupational Hazard Review: Aldrin/Dieldrin p.32 (1978) DHEW Pub. NIOSH 78-201]**PEER REVIEWED**
  
• LD50 Rat male dermal (20% emulsification concn) 213.8 mg/kg [NIOSH; Special Occupational Hazard Review: Aldrin/Dieldrin p.32 (1978) DHEW Pub. NIOSH 78-201]**PEER REVIEWED**
  
• LD50 Rat female dermal (20% emulsification concn) 119.9 mg/kg [NIOSH; Special Occupational Hazard Review: Aldrin/Dieldrin p.32 (1978) DHEW Pub. NIOSH 78-201]**PEER REVIEWED**
  
• LD50 Rat dermal (50% wettable powder) 213.4 mg/kg [NIOSH; Special Occupational Hazard Review: Aldrin/Dieldrin p.32 (1978) DHEW Pub. NIOSH 78-201]**PEER REVIEWED**
  
• LD50 CAPRA HIRCUS (DOMESTIC GOAT) MALE ORAL 100-200 MG/KG, 6-8 MO OLD [U.S. Department of the Interior, Fish and Wildlife Service. Handbook of Toxicity of Pesticides to Wildlife. Resource Publication 153. Washington, DC: U.S. Government Printing Office, 1984., p. 31]**PEER REVIEWED**
  
• LD50 Rat male oral 47 mg/kg [Hayes, W.J., Jr., E.R. Laws, Jr., (eds.). Handbook of Pesticide Toxicology. Volume 2. Classes of Pesticides. New York, NY: Academic Press, Inc., 1991., p. 828]**PEER REVIEWED**
  
• LD50 Rat female oral 38 mg/kg [Hayes, W.J., Jr., E.R. Laws, Jr., (eds.). Handbook of Pesticide Toxicology. Volume 2. Classes of Pesticides. New York, NY: Academic Press, Inc., 1991., p. 828]**PEER REVIEWED**
  
• LD50 Rat newborn male oral 167 mg/kg [Hayes, W.J., Jr., E.R. Laws, Jr., (eds.). Handbook of Pesticide Toxicology. Volume 2. Classes of Pesticides. New York, NY: Academic Press, Inc., 1991., p. 828]**PEER REVIEWED**
  
• LD50 Rat preweanling male oral 24 mg/kg [Hayes, W.J., Jr., E.R. Laws, Jr., (eds.). Handbook of Pesticide Toxicology. Volume 2. Classes of Pesticides. New York, NY: Academic Press, Inc., 1991., p. 828]**PEER REVIEWED**
  
• LD50 Rat male dermal 90 mg/kg [Hayes, W.J., Jr., E.R. Laws, Jr., (eds.). Handbook of Pesticide Toxicology. Volume 2. Classes of Pesticides. New York, NY: Academic Press, Inc., 1991., p. 828]**PEER REVIEWED**
  
• LD50 Rat female dermal 60 mg/kg [Hayes, W.J., Jr., E.R. Laws, Jr., (eds.). Handbook of Pesticide Toxicology. Volume 2. Classes of Pesticides. New York, NY: Academic Press, Inc., 1991., p. 828]**PEER REVIEWED**
  
• LD50 Rabbit dermal < 150 mg/kg [Hayes, W.J., Jr., E.R. Laws, Jr., (eds.). Handbook of Pesticide Toxicology. Volume 2. Classes of Pesticides. New York, NY: Academic Press, Inc., 1991., p. 828]**PEER REVIEWED**
  
• LD50 Rat acute oral 37-87 g/kg [Montgomery, J.H.; Agrochemicals Desk Reference 2nd ed. Lewis Publishers, Boca Raton, FL 1997, p. 173]**PEER REVIEWED**
  
• LD50 Rat oral 38,300 ug/kg [Lewis, R.J. Sax's Dangerous Properties of Industrial Materials. 9th ed. Volumes 1-3. New York, NY: Van Nostrand Reinhold, 1996., p. 1141]**PEER REVIEWED**
  
• LD50 Rat skin 56 mg/kg [Lewis, R.J. Sax's Dangerous Properties of Industrial Materials. 9th ed. Volumes 1-3. New York, NY: Van Nostrand Reinhold, 1996., p. 1141]**PEER REVIEWED**
  
• LD50 Rat ip 35 mg/kg [Lewis, R.J. Sax's Dangerous Properties of Industrial Materials. 9th ed. Volumes 1-3. New York, NY: Van Nostrand Reinhold, 1996., p. 1141]**PEER REVIEWED**
  
• LD50 Rat iv 9 mg/kg [Lewis, R.J. Sax's Dangerous Properties of Industrial Materials. 9th ed. Volumes 1-3. New York, NY: Van Nostrand Reinhold, 1996., p. 1141]**PEER REVIEWED**
  
• LD50 Mouse oral 38 mg/kg [Lewis, R.J. Sax's Dangerous Properties of Industrial Materials. 9th ed. Volumes 1-3. New York, NY: Van Nostrand Reinhold, 1996., p. 1141]**PEER REVIEWED**
  
• LD50 Mouse iv 10.5 mg/kg [Lewis, R.J. Sax's Dangerous Properties of Industrial Materials. 9th ed. Volumes 1-3. New York, NY: Van Nostrand Reinhold, 1996., p. 1141]**PEER REVIEWED**
  
• LD50 Dog oral 65 mg/kg [Lewis, R.J. Sax's Dangerous Properties of Industrial Materials. 9th ed. Volumes 1-3. New York, NY: Van Nostrand Reinhold, 1996., p. 1141]**PEER REVIEWED**
  
• LD50 Monkey oral 3 mg/kg [Lewis, R.J. Sax's Dangerous Properties of Industrial Materials. 9th ed. Volumes 1-3. New York, NY: Van Nostrand Reinhold, 1996., p. 1141]**PEER REVIEWED**
  

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Absorption, Distribution and Excretion

• ... IN OIL SOLN /IT/ IS ABSORBED VERY READILY THROUGH SKIN, RESP MUCOSA & GI TRACT. [Gosselin, R.E., R.P. Smith, H.C. Hodge. Clinical Toxicology of Commercial Products. 5th ed. Baltimore: Williams and Wilkins, 1984., p. III-143]**PEER REVIEWED**
  
• ... (36)CL DIELDRIN ... RAPIDLY ABSORBED AFTER ORAL ADMIN TO RATS & WEANLING PIGS ... LOCALIZED IN LIVER & FAT DEPOTS, FROM WHICH ... /IT IS/ ONLY SLOWLY EXCRETED. [Parke, D. V. The Biochemistry of Foreign Compounds. Oxford: Pergamon Press, 1968., p. 200]**PEER REVIEWED**
  
• CONCN OF DIELDRIN IN PLASMA OF ... PREGNANT WOMEN RANGED FROM 0.0001-0.0061 PPM, & CONCN IN WHOLE-CORD BLOOD OF NEWBORN BABIES RANGED FROM 0.0002-0.0015 PPM. SIMILAR BLOOD LEVELS IN MOTHERS & NEWBORN BABIES WERE ... REPORTED ... . [IARC. Monographs on the Evaluation of the Carcinogenic Risk of Chemicals to Man. Geneva: World Health Organization, International Agency for Research on Cancer, 1972-PRESENT. (Multivolume work)., p. V5 140 (1974)]**PEER REVIEWED**
  
• WHOLE BODY AUTORADIOGRAPHY OF PREGNANT MICE DOSED IM WITH (14)C DIELDRIN SHOWED ... UPTAKE OF (14)C OCCURRED IN ADIPOSE TISSUE. DIELDRIN CROSSED PLACENTA, & UPTAKE INTO FETAL TISSUES, ALTHOUGH MODERATE, PARALLELED THAT IN MATERNAL TISSUES. [The Chemical Society. Foreign Compound Metabolism in Mammals. Volume 1: A Review of the Literature Published Between 1960 and 1969. London: The Chemical Society, 1970., p. 76]**PEER REVIEWED**
  
• DIELDRIN IS STORED IN ADIPOSE TISSUE, LIVER, BRAIN & MUSCLE OF MAMMALS, FISH & BIRDS, IN ALGAE, PLANKTON, INSECTS, EARTHWORMS & IN EGGS OF MANY BIRD SPECIES. FISH CAN BUILD UP MG/KG CONCN OF DIELDRIN FROM NG/L CONCN IN WATER ... . [IARC. Monographs on the Evaluation of the Carcinogenic Risk of Chemicals to Man. Geneva: World Health Organization, International Agency for Research on Cancer, 1972-PRESENT. (Multivolume work)., p. V5 130 (1974)]**PEER REVIEWED**
  
• IN PLASMA ... DIELDRIN ... ASSOCIATED MAINLY WITH ALPHA- & BETA-LIPOPROTEIN FRACTION. [Spencer, E. Y. Guide to the Chemicals Used in Crop Protection. 7th ed. Publication 1093. Research Institute, Agriculture Canada, Ottawa, Canada: Information Canada, 1982., p. 238]**PEER REVIEWED**
  
• DIELDRIN RESIDUES IN GRAY SEALS SAMPLED DURING BREEDING SEASON. MEAN BLUBBER ORGANOHALOGEN CONCN OF MALES WAS GREATER THAN FEMALES. DIELDRIN WAS DETECTED IN LIVER OF MOTHER/FETUS PAIRS DEMONSTRATING TRANSPLACENTAL MOVEMENT OF THESE RESIDUES. [DONKIN ET AL; SCI TOTAL ENVIRON 19 (2): 121-42 (1981)]**PEER REVIEWED**
  
• SIMPLE CORRELATIONS BETWEEN BRAIN & CARCASS CONCN OF DIELDRIN WERE MOST SIGNIFICANT. BRAIN RESIDUE LEVELS WERE NEG CORRELATED WITH CARCASS LIPID LEVELS & WERE PREDICTABLE WITHIN FACTOR OF APPROX 2. PESTICIDES TESTED VARIED IN PROPENSITY TO ACCUM IN BRAIN. [BARBEHENN KR & REICHEL WL; J TOXICOL ENVIRON HEALTH 8 (1-2): 325-30 (1981)]**PEER REVIEWED**
  
• DERMAL PENETRATION OFLABELED DIELDRIN. HALF LIFE FOR DIELDRIN 71.7 + or - 17.3%. AT 8 HR 82.6% HAD LEFT SITE OF APPLICATION IN MICE WITH SIGNIFICANT RADIOACTIVITY IN STOMACH 1.4%;INTESTINE 8.5%; LIVER 3.1%. EXCRETORY PRODUCTS, PRIMARILY FECES, CONTAINED 3.6%; CARCASS HAD 61.7%. [SHAH ET AL; TOXICOL APPL PHARMACOL 59 (3): 414-23 (1981)]**PEER REVIEWED**
  
• EXPOSURE OF BLUEGILL FISH TO 50 PPB IN STATIC SYSTEM RESULTED IN ABSORPTION OF 73% OF RADIOACTIVITY IN 48 HR. WHEN TRANSFERRED TO CLEAN WATER ONLY 16.20% OF ABSORBED RADIOLABEL ELIM IN 23 DAYS. TWO METAB ISOLATED INCL PENTACHLOROKETONE & ALDRIN-TRANS-DIOL. [SUDERSHAN P, KHAN MAS; PESTIC BIOCHEM PHYSIOL 15 (29): 192-9 (1981)]**PEER REVIEWED**
  
• HUMAN MILK SAMPLES FROM 1436 WOMEN RESIDING IN USA WERE ANALYZED BY GLC FOR PESTICIDES. DIELDRIN WAS FOUND ABOVE THE DETECTION LIMIT (1.0 PPB) IN MORE THAN 80% OF ALL THE SAMPLES COLLECTED. [SAVAGE ET AL; AM J EPIDEMIOL 113 (4): 413-22 (1981)]**PEER REVIEWED**
  
• Dieldrin is slowly excreted in the bile. Samples taken from a pest control operator during surgery contained dieldrin at concn of 24.6 ppm in adipose tissue, 165 ppb in blood serum, and 159 ppb in bile. [NIOSH; Special Occupational Hazard Review: Aldrin/Dieldrin p.27 (1978) DHEW Pub. NIOSH 78-201]**PEER REVIEWED**
  
• 14 aldrin/dieldrin workers exhibited a statistically significant incr over controls in urinary excretion of D-glutaric acid. ... Dieldrin levels in the blood of workers averaged 0.026 ug/ml but were not significantly correlated with D-glutaric acid excretion. [NIOSH; Special Occupational Hazard Review: Aldrin/Dieldrin p.88 (1978) DHEW Pub. NIOSH 78-201]**PEER REVIEWED**
  
• Biliary excretion has been shown for /dieldrin/. [Hayes, W.J., Jr., E.R. Laws Jr., (eds.). Handbook of Pesticide Toxicology Volume 1. General Principles. New York, NY: Academic Press, Inc., 1991., p. 154]**PEER REVIEWED**
  
• Studies using human serum proteins demonstrated that binding of /dieldrin/ ... was primarily to the albumin and lipoprotein fractions and was low-affinity hydropholic binding. [Hayes, W.J., Jr., E.R. Laws Jr., (eds.). Handbook of Pesticide Toxicology Volume 1. General Principles. New York, NY: Academic Press, Inc., 1991., p. 154]**PEER REVIEWED**
  
• ... Dieldrin was below the level of detection in cord blood even though it was present in the blood of mothers indicating a relatively efficient placental barrier to this compound /in humans/. [Hayes, W.J., Jr., E.R. Laws, Jr., (eds.). Handbook of Pesticide Toxicology. Volume 2. Classes of Pesticides. New York, NY: Academic Press, Inc., 1991., p. 839]**PEER REVIEWED**
  
• Dieldrin is eliminated in human urine as at least two neutral polar metabolites. Unchanged dieldrin is not excreted ... . [Hayes, W.J., Jr., E.R. Laws, Jr., (eds.). Handbook of Pesticide Toxicology. Volume 2. Classes of Pesticides. New York, NY: Academic Press, Inc., 1991., p. 839]**PEER REVIEWED**
  
• Dieldrin is absorbed from the GI tract via the hepatic portal vein. ... The high toxicity of dieldrin when applied to the skin is evidence for the rapid absorption of the compound by that route. Hemoglobin is largely but not entirely responsible for binding dieldrin in erythrocytes. ... Dieldrin is relatively slowly absorbed from the small intestine, peak blood levels occurring in rats 2.5 hr after administration. For serum, dieldrin was bound to lipoprotein and globulins and to a lesser extent albumin. [Hayes, W.J., Jr., E.R. Laws, Jr., (eds.). Handbook of Pesticide Toxicology. Volume 2. Classes of Pesticides. New York, NY: Academic Press, Inc., 1991., p. 830]**PEER REVIEWED**
  
• In studies with protein derived from rat blood, binding of dieldrin was shown to be of a nonspecific hydrophobic nature. [Menzie, C.M. Metabolism of Pesticides-Update III. Special Scientific Report- Wildlife No. 232. Washington, DC: U.S.Department of the Interior, Fish and Wildlife Service, 1980., p. 12]**PEER REVIEWED**
  
• A single dose of (14)C-labeled dieldrin was given by stomach tube to Sprague Dawley rats. The dose was quickly absorbed and transported to the liver. Only a portion was metabolized and excreted. The major portion was redistributed and stored in adipose tissue. [Menzie, C.M. Metabolism of Pesticides-Update III. Special Scientific Report- Wildlife No. 232. Washington, DC: U.S.Department of the Interior, Fish and Wildlife Service, 1980., p. 12]**PEER REVIEWED**
  
• In channel catfish (Ictalurus punctatus) exposed continuously to dieldrin, equilibrium between uptake and elimination was reached in 56 days at 13 and 27 ppt but not until after 70 days when the exposure level was 49 parts per trillion. [Menzie, C.M. Metabolism of Pesticides-Update III. Special Scientific Report- Wildlife No. 232. Washington, DC: U.S.Department of the Interior, Fish and Wildlife Service, 1980., p. 12]**PEER REVIEWED**
  
• Aldrin and dieldrin can be absorbed by inhalational, dermal, and gastrointestinal routes. There is a rapid conversion of aldrin to the dieldrin epoxide once absorption has occurred. ... Dieldrin is stored in the fat and during periods of stress, such as weight loss and high fever, can be mobilized to the plasma where it can be metabolized. [Sullivan, J.B. Jr., G.R. Krieger (eds.). Hazardous Materials Toxicology-Clinical Principles of Environmental Health. Baltimore, MD: Williams and Wilkins, 1992., p. 1044]**PEER REVIEWED**
  
• The clinical toxicology of aldrin and dieldrin can essentially be ascribed to dieldrin, since aldrin is rapidly metabolized to dieldrin after absorption in the human body. Once converted, dieldrin is distributed extensively into tissue spaces and accumulates in adipose tissue. Dieldrin is metabolized hepatically, and metabolites are excreted in bile and feces. [Sullivan, J.B. Jr., G.R. Krieger (eds.). Hazardous Materials Toxicology-Clinical Principles of Environmental Health. Baltimore, MD: Williams and Wilkins, 1992., p. 1044]**PEER REVIEWED**
  
• Thirteen volunteers were given dieldrin by mouth for 18 months; in 9 of them the daily dose ranged 10 to 211 ug. ... The avg concn of dieldrin in fat was 156 times that in the blood. [Reynolds, J.E.F., Prasad, A.B. (eds.) Martindale-The Extra Pharmacopoeia. 28th ed. London: The Pharmaceutical Press, 1982., p. 836]**PEER REVIEWED**
  

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Metabolism/Metabolites

• IN MALE RATS & MICE, TRANS-4,5-DIHYDROXY-4,5-DIHYDROALDRIN ... IS FECAL METABOLITE & 4,5-SECO-ALDRIN-4,5-DICARBOXYLIC ACID IS A URINARY METABOLITE OF DIELDRIN. [The Chemical Society. Foreign Compound Metabolism in Mammals Volume 3. London: The Chemical Society, 1975., p. 402]**PEER REVIEWED**
  
• WHEN LABELED DIELDRIN ... ADMIN TO RABBIT VIA STOMACH TUBE, SIX METABOLITES ... ISOLATED ... MAIN METABOLITE ... IDENTIFIED AS ONE OF TWO ENANTIOMORPHIC ISOMERS OF 6,7-TRANS DIHYDROXY-DIHYDRO-ALDRIN (ALDRIN DIOL). [Menzie, C.M. Metabolism of Pesticides. U.S. Department of the Interior, Bureau of Sport Fisheries and Wildlife, Publication 127. Washington, DC: U.S. Government Printing Office, 1969., p. 24]**PEER REVIEWED**
  
• AFTER FEEDING LABELED DIELDRIN TO SHEEP, SIX METABOLITES ... FOUND IN URINE. ... ONE WAS GLUCURONIC ACID CONJUGATE OF TRANS-DIOL & OTHER CONJUGATE CONTAINING GLUCURONIC ACID & POSSIBLY GLYCINE. ... FOUR WERE HEXANE SOL. ONE ... /WAS/ TRANS-DIOL. OTHER ... SYN-EPOXY-HYDROXYDIELDRIN. [Menzie, C. M. Metabolism of Pesticides, An Update. U.S. Department of the Interior, Fish, Wild-life Service, Special Scientific Report - Wildlife No. 184, Washington, DC: U.S. Government Printing Office, l974., p. 16]**PEER REVIEWED**
  
• ... IV TO RHESUS MONKEYS. ... THREE /METABOLITES/ ... IDENTIFIED: 12-HYDROXYDIELDRIN; 4,5-ALDRIN-TRANS-DIHYDRODIOL & GLUCURONIC ACID CONJUGATE OF DIOL. ... PENTACHLOROKETONE ... EXCRETED BY RATS ... RHESUS MONKEYS EXCRETED 9-HYDROXYDIELDRIN. BILE CONTAINED GLUCURONIDE OF 9-HYDROXYDIELDRIN BUT NO PENTACHLOROKETONE. [Menzie, C.M. Metabolism of Pesticides, Update II. U.S. Department of the Interior, Fish Wildlife Service, Special Scientific Report - Wildlife No. 2l2. Washington, DC: U.S. Government Printing Office, 1978., p. 5]**PEER REVIEWED**
  
• When (14)C dieldrin was administered to rats ... as a single dose ... one of the fecal metabolites ... was identified as 6,7-trans-dihydroaldrindiol, and one of the urinary metabolites as hexachlorohexahydromethanoindene-1,3-dicarboxylic acid. [IARC. Monographs on the Evaluation of the Carcinogenic Risk of Chemicals to Man. Geneva: World Health Organization, International Agency for Research on Cancer, 1972-PRESENT. (Multivolume work)., p. V5 139 (1974)]**PEER REVIEWED**
  
• Four metabolic products of dieldrin in rodents include: 6,7-trans-dihydroxy-dihydroaldrin, tricyclic dicarboxylic acid, syn-1,2-hydroxy-dieldrin, and pentachloroketone. [USEPA; Hazard Profile: Dieldrin p.5 (1980)]**PEER REVIEWED**
  
• Time courses (0-100 days) of uptake and metabolism of aldrin and dieldrin added as a subculture to suspension cultures from Phaseolus vulgaris (French bean) root and shoot and Solanom tubersum (potato) tuber were comparable with rapid dieldrin production and delayed appearance of other metabolites. When aldrin and dieldrin were added to cultures 10 or 20 days after subculture, usual extent of conversion of aldrin to dieldrin occurred, but with reduced production of other metabolites. Increased vol of 2-methoxyethanol had detrimental effects on growth and uptake and metabolism. Dieldrin production was maximal during the rapid growth phase and probably independent of other conversions. [Brain KR, Lines DS; Plent Cell Rep 2 (1): 11-4 (1983)]**PEER REVIEWED**
  
• Rats fed 200 ppm dieldrin in the diet showed cellular changes within 24 hours. These changes were correlated with an increased activity of certain enzymes, such as those capable of hydroxylating aniline or catalyzing the o-dealkylation of chlorofenviphos, but activity of ... acid phosphatase or glucose-6-phosphatase did not change. [NIOSH; Special Occupational Hazard Review: Aldrin/Dieldrin p.42 (1978) DHEW Pub. NIOSH 78-201]**PEER REVIEWED**
  
• ... WORKERS WITH OCCUPATIONAL EXPOSURE TO DIELDRIN & ALDRIN EXCRETED 9-HYDROXY-DIELDRIN IN FECES. [IARC. Monographs on the Evaluation of the Carcinogenic Risk of Chemicals to Man. Geneva: World Health Organization, International Agency for Research on Cancer, 1972-PRESENT. (Multivolume work)., p. V5 140 (1974)]**PEER REVIEWED**
  
• The comparative metabolism of dieldrin in rats and in mice receiving a single dose of dieldrin was investigated. Differences were primarily quantitative. Fecal metabolites from the CFE rats included 12-hydroxydieldrin; 4,5-trans- and cis-dihydroaldrindiol and aldrin dicarboxylic acid (or dihydrochlordenedicarboxylic acid). In the rat urine, there were no metabolites with a polarity greater than aldrin dicarboxylic. Mouse urine, however, contained a relatively large amount of polar metabolites. Compounds identified in urine included 12-hydrdoxydieldrin glucuronide and pentachloroketone. In urine of mice, the latter compound appeared only as a trace unless-mice were pretreated with dieldrin. Liver and fat residues were higher in mice than in rats. In rats, however, kidney residues were much higher than in mice. This reflected the presence of pentachloroketone. Tissue residues in mice and rats were highest for fieldrin and ranged up to 3.3 ppm in liver and 66.0 ppm in fat. Maximum residues of other metabolites were: 0.51 ppm 12-hydroxydieldrin; 6.11 ppm pentachloroketone; <0.18 ppm photodieldrin; and 0.020 ppm trans-dihydroaldrin. [Menzie, C.M. Metabolism of Pesticides-Update III. Special Scientific Report- Wildlife No. 232. Washington, DC: U.S.Department of the Interior, Fish and Wildlife Service, 1980., p. 12]**PEER REVIEWED**
  
• Photodieldrin was administered in feed or by injection to male rabbits. Urine and feces were collected for every 24 hr for 9 d. About 10-13% of the administered dose was released by beta-glucuronidase from the aqueous phase of the urine analysis; about 2 to 3% by 1N HCl. In addition to photodieldrin, six metabolites were observed with TLC. Of these, photodieldrin trans-diol and photodieldrin ketone were identified by means of IR and GC-MS. /Photodieldrin/ [Menzie, C.M. Metabolism of Pesticides-Update III. Special Scientific Report- Wildlife No. 232. Washington, DC: U.S.Department of the Interior, Fish and Wildlife Service, 1980., p. 14]**PEER REVIEWED**
  
• In human volunteers ingesting dieldrin, dieldrin concentrations in blood and fat tissue increased in a dose related fashion with the fat tissue to blood ratio being 136:1. ... The concentration of dieldrin in humans reaches a constant concentration and that the amount ingested and absorbed equals the amount metabolized and excreted after a period of time. With the increasing concentration of dieldrin in the liver, the rate of metabolism increases. [Sullivan, J.B. Jr., G.R. Krieger (eds.). Hazardous Materials Toxicology-Clinical Principles of Environmental Health. Baltimore, MD: Williams and Wilkins, 1992., p. 1044]**PEER REVIEWED**
  
• Transplacental passage of dieldrin has been demonstrated in rabbits, rats, pigs, and cows. [IARC. Monographs on the Evaluation of the Carcinogenic Risk of Chemicals to Man. Geneva: World Health Organization, International Agency for Research on Cancer, 1972-PRESENT. (Multivolume work)., p. V5 140 (1974)]**PEER REVIEWED**
  
• The present study provides the evidence that dieldrin is reductively metabolized to aldrin by intestinal bacteria in rats. When dieldrin was incubated with the cecal contents of rats, aldrin, a reduced metabolite of the epoxide, was isolated from the incubation mixture. The metabolite was identified unequivocally by UV & mass spectral comparison with an authentic sample, & on the basis of its TLC & HPLC behavior. The cecal contents of rats exhibited epoxide reductase activity toward dieldrin under anaerobic conditions. However, only marginal activity was observed under aerobic conditions. Four pure strains of intestinal bacteria exhibited epoxide reductase activities to varying degrees under anaerobic conditions. The highest activity was observed in Clostridium sporogenes. Cell-free extracts of the intestinal bacteria in rat cecal contents showed reductase activity when supplemented with both NAD(P)H & FMN under anaerobic conditions. [KITAMURA S et al.; Bio Pharm Bull 22 (8): 880-882 (1999)]**PEER REVIEWED**
  

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TSCA Test Submissions

• None found

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Footnotes

¹ Source: the National Library of Medicine's Hazardous Substance Database, 10/28/2007.