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Lee JH, Kim I, Seok H, Park I, Hwang J, Park JO, Won JU, Roh J. Case report of renal cell carcinoma in automobile manufacturing factory worker due to trichloroethylene exposure in Korea. Ann Occup Environ Med 2015; 27:19. [PMID: 26240754 PMCID: PMC4522957 DOI: 10.1186/s40557-015-0068-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2014] [Accepted: 06/29/2015] [Indexed: 01/20/2023] Open
Abstract
BACKGROUND The aim of this paper was report first case of renal cell carcinoma developed in a worker who worked in an automobile manufacture line which handles trichloroethylene in Korea. CASE PRESENTATION To clarify the relationship between the onset of renal cell carcinoma in 52-years old male worker and the exposure to trichloroethylene, document studies and work environment measurement were done. Past work environment exposure data were reviewed and medical history and surgery records of the worker were also reviewed. The patient had no personal risk factor related to renal cell carcinoma except for his smoking habit of quarter a pack per day for twenty years, and since trichloroethylene was not part of measurement criteria, past work environment risk assessment data could not verify the exposure. The exposure level is deduced by analyzing material exposure level of work environments which has similar processes in data from revised research of chemical exposure standard and work environment validity assessment. Evaluation Committee of Epidemiologic Survey decided that there are relevant relationship between the exposure and the disease, though we do not have exact data during that period, most experts agree that in every factories they used trichloroethylene without any direction. CONCLUSIONS From the relevant medical history and the results of the usage of trichloroethylene in the relevant industries, and initial discovery of renal cell carcinoma at health inspection sonogram in 2001, it can be concluded that suggests significant causal relationship between the exposure to trichloroethylene and renal cell carcinoma onset, thus reporting it to be the first domestic case declared to be occupational disease.
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Affiliation(s)
- June-Hee Lee
- Graduate School of Public Health, Yonsei University, 50 Seongsanno (134 Sinchon-dong), Seodaemun-gu, Seoul, South Korea ; The Institute for Occupational Health, Yonsei University College of Medicine, Seoul, South Korea
| | - Inah Kim
- Department of Occupational and Environmental Medicine, Hanyang University College of Medicine, Seoul, South Korea
| | - Hongdeok Seok
- Graduate School of Public Health, Yonsei University, 50 Seongsanno (134 Sinchon-dong), Seodaemun-gu, Seoul, South Korea ; The Institute for Occupational Health, Yonsei University College of Medicine, Seoul, South Korea
| | - Inhyo Park
- Graduate School of Public Health, Yonsei University, 50 Seongsanno (134 Sinchon-dong), Seodaemun-gu, Seoul, South Korea
| | - Jungho Hwang
- The Institute for Occupational Health, Yonsei University College of Medicine, Seoul, South Korea
| | - Jae-Oh Park
- Occupational Safety and Health Research Institute, Korea Occupational Safety and Health Agency, Ulsan, South Korea
| | - Jong-Uk Won
- Graduate School of Public Health, Yonsei University, 50 Seongsanno (134 Sinchon-dong), Seodaemun-gu, Seoul, South Korea ; The Institute for Occupational Health, Yonsei University College of Medicine, Seoul, South Korea ; Department of Preventive Medicine and Public Health, Yonsei University College of Medicine, Seoul, South Korea
| | - Jaehoon Roh
- Graduate School of Public Health, Yonsei University, 50 Seongsanno (134 Sinchon-dong), Seodaemun-gu, Seoul, South Korea ; The Institute for Occupational Health, Yonsei University College of Medicine, Seoul, South Korea ; Department of Preventive Medicine and Public Health, Yonsei University College of Medicine, Seoul, South Korea
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Umezu T, Shibata Y. Different behavioral effect dose-response profiles in mice exposed to two-carbon chlorinated hydrocarbons: influence of structural and physical properties. Toxicol Appl Pharmacol 2014; 279:103-12. [PMID: 24910396 DOI: 10.1016/j.taap.2014.05.012] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2014] [Revised: 04/30/2014] [Accepted: 05/27/2014] [Indexed: 11/24/2022]
Abstract
The present study aimed to clarify whether dose-response profiles of acute behavioral effects of 1,2-dichloroethane (DCE), 1,1,1-trichloroethane (TCE), trichloroethylene (TRIC), and tetrachloroethylene (PERC) differ. A test battery involving 6 behavioral endpoints was applied to evaluate the effects of DCE, TCE, TRIC, and PERC in male ICR strain mice under the same experimental conditions. The behavioral effect dose-response profiles of these compounds differed. Regression analysis was used to evaluate the relationship between the dose-response profiles and structural and physical properties of the compounds. Dose-response profile differences correlated significantly with differences in specific structural and physical properties. These results suggest that differences in specific structural and physical properties of DCE, TCE, TRIC, and PERC are responsible for differences in behavioral effects that lead to a variety of dose-response profiles.
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Affiliation(s)
- Toyoshi Umezu
- Center for Environmental Measurement and Analysis, National Institute for Environmental Studies, Tsukuba, Ibaraki 305-8506, Japan.
| | - Yasuyuki Shibata
- Center for Environmental Measurement and Analysis, National Institute for Environmental Studies, Tsukuba, Ibaraki 305-8506, Japan.
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Keil DE, Peden-Adams MM, Wallace S, Ruiz P, Gilkeson GS. Assessment of trichloroethylene (TCE) exposure in murine strains genetically-prone and non-prone to develop autoimmune disease. JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH. PART A, TOXIC/HAZARDOUS SUBSTANCES & ENVIRONMENTAL ENGINEERING 2009; 44:443-453. [PMID: 19241258 DOI: 10.1080/10934520902719738] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
There is increasing laboratory and epidemiologic evidence relating exposure to trichloroethylene (TCE) with autoimmune disease including scleroderma and lupus. New Zealand Black/New Zealand White (NZBWF1) and B6C3F1 mice were exposed to TCE (0, 1, 400 or 14,000 ppb) via drinking water for 27 or 30 weeks, respectively. NZBWF1 mice spontaneously develop autoimmune disease while B6C3F1 mice, a standard strain used in immunotoxicology testing, are not genetically prone to develop autoimmune disease. During the TCE exposure period, serum levels of total IgG, and autoantibodies (anti-ssDNA, -dsDNA, and -glomerular antigen [GA]) were monitored. At the termination of the study, renal pathology, natural killer (NK) cell activity, total IgG levels, autoantibody production, T-cell activation, and lymphocytic proliferative responses were evaluated. TCE did not alter NK cell activity, or T- and B-cell proliferation in either strain. Numbers of activated T-cells (CD4+/CD44+) were increased in the B6C3F1 mice but not in the NZBWF1 mice. Renal pathology, as indicated by renal score, was significantly increased in the B6C3F1, but not in the NZBWF1 mice. Serum levels of autoantibodies to dsDNA and ssDNA were increased at more time points in B6C3F1, as compared to the NZBWF1 mice. Anti-GA autoantibodies were increased by TCE treatment in early stages of the study in NZBWF1 mice, but by 23 weeks of age, control levels were comparable to those of TCE-exposed animals. Serum levels anti-GA autoantibodies in B6C3F1 were not affected by TCE exposure. Overall, these data suggest that TCE did not contribute to the progression of autoimmune disease in autoimmune-prone mice during the period of 11-36 weeks of age, but rather lead to increased expression of markers associated with autoimmune disease in a non-genetically prone mouse strain.
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Affiliation(s)
- Deborah E Keil
- Clinical Laboratory Sciences Program, University of Nevada-Las Vegas, Las Vegas, Nevada, USA.
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Gilbert KM, Blossom SJ, Pumford NR. Comments on "Lifetime exposure to trichloroethylene (TCE) does not accelerate autoimmune disease in MRL+/- mice. JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH. PART A, TOXIC/HAZARDOUS SUBSTANCES & ENVIRONMENTAL ENGINEERING 2009; 44:116-122. [PMID: 19085602 DOI: 10.1080/10934520802656584] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
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Lefrou L, Barbieux JP, Barbieux C, Metman EH. [Cystic pneumatosis of the colon and professional trichloroethylene exposure]. GASTROENTEROLOGIE CLINIQUE ET BIOLOGIQUE 2007; 31:1072-1073. [PMID: 18176359 DOI: 10.1016/s0399-8320(07)78337-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Affiliation(s)
- Laurent Lefrou
- Service de gastroentérologie, Hôpital Trousseau, CHU de Tours, 37044 Tours Cedex 9
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Guengerich FP, Cai H, Johnson WW, Parikh A. Reactive intermediates in biological systems: what have we learned and where are we going? ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2002; 500:639-50. [PMID: 11765010 DOI: 10.1007/978-1-4615-0667-6_96] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Affiliation(s)
- F P Guengerich
- Department of Biochemistry and Center in Molecular Toxicology, Vanderbilt University School of Medicine, Nashville, TN 37232, USA
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7
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Wang RS, Nakajima T, Tsuruta H, Honma T. Effect of exposure to four organic solvents on hepatic cytochrome P450 isozymes in rat. Chem Biol Interact 1996; 99:239-52. [PMID: 8620572 DOI: 10.1016/0009-2797(95)03673-3] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Changes of cytochrome P450 isozymes in livers of rats after exposure to four solvents at 4000 ppm for 6 h, were studied by enzyme assays and immunochemical detection using antibodies to cytochrome P450 isozymes. Toluene, benzene and trichloroethylene (TRI) exposure resulted in a significant increase in the activities of nitrosodimethylamine demethylase (152%, 134% and 118%) and 7-pentoxyresorufin O-depentylase (14-, 5- and 2.5-fold), respectively. 1,1,1-Trichloroethane (TCE) showed little effect on the activities of the enzymes. Anti-CYP2E1 and anti-CYP2B1/2 inhibitable activity of toluene side-chain oxidase was significantly enhanced in toluene-, benzene- and TRI-treated rats. Anti-CYP2C11 inhibitable activity was greatly reduced as compared with control. The change in CYP2E1 and CYP2C11 was confirmed by the increase and decrease in the activities inhibited by 4-methylpyrazole and cimetidine, respectively. Western blot analysis revealed that the increase in peak area of bands recognized by anti-CYP2E1 was consistent with toluene inhibition results. CYP2B1/2 was not detectable in control rats, but it was strongly induced by toluene, followed by benzene and TRI. Some increases in the peak areas of bands recognized by anti-CYP2A1 and CYP-4A1 were also observed in the three solvents exposed rat microsomes. Little immunoreactivity was found with anti-CYP1A1 in all microsomes, and no obvious change in peak area of bands recognized by anti-CYP3A and anti-CYP2C13 was observed. TCE exposure showed little effect on these bands. The formation of phenol and hydroquinone from benzene was enhanced to different degree by toluene, benzene and TRI. The hydroxylation of testosterone at 6 beta and 7 alpha was increased by benzene, and benzene and TRI, respectively. However, the metabolism at 16 alpha and 2 alpha was profoundly suppressed by the solvents except TCE. These results showed that the four solvents have different effects on specific cytochrome P450 isozymes and on the metabolism of both endogenous and exogenous substances.
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Affiliation(s)
- R S Wang
- Department of Occupational Diseases, National Institute of Industrial Health, Kawasaki, Japan
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Kligerman AD, Bryant MF, Doerr CL, Erexson GL, Evansky PA, Kwanyuen P, McGee JK. Inhalation studies of the genotoxicity of trichloroethylene to rodents. Mutat Res 1994; 322:87-96. [PMID: 7519326 DOI: 10.1016/0165-1218(94)00013-1] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Trichloroethylene (TCE) (CAS No. 79-01-6) is an industrial solvent used in degreasing, dry cleaning, and numerous other medical and industrial processes. Controlled inhalation studies were performed using male C57BL/6 mice and CD rats to determine if TCE can induce cytogenetic damage in vivo. Animals were exposed in groups of five to target concentrations of either 0, 5, 500, or 5000 ppm TCE for 6 h. Tissue samples were taken between 18 and 19 h post exposure. Peripheral blood lymphocytes (PBLs) in rats and splenocytes in mice were cultured and analyzed for the induction of sister-chromatid exchanges, chromosome aberrations, and micronuclei (MN) in cytochalasin B-blocked binucleated cells. Bone marrow polychromatic erythrocytes (PCEs) were analyzed for MN. The only positive response observed was for MN in rat bone marrow PCEs. TCE caused a statistically significant increase in MN at all concentrations, inducing an approximate fourfold increase over control levels at 5000 ppm. TCE was also cytotoxic in rats, causing a significant concentration-related decrease in the ratio of PCEs/normochromatic erythrocytes. This study indicates that there may be species-specific cytogenetic effects attributed to TCE inhalation exposure. In follow-up studies, CD rats were exposed for 6 h/day over 4 consecutive days to either 0, 5, 50 or 500 ppm TCE. No statistically significant concentration-related increases in cytogenetic damage were observed. While the MN frequencies in the 4-day study were comparable to those at the equivalent concentrations in the 1-day study, they were not significantly elevated due to an unusually high MN frequency in the controls. A subsequent replication of the 1-day 5000 ppm TCE exposure with rats again showed a highly significant increase in MN frequencies compared to concurrent controls.
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Affiliation(s)
- A D Kligerman
- Department of Genetic Toxicology, US Environmental Protection Agency, Research Triangle Park, NC 27710
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Okamoto T, Shiwaku K. Fatty acid composition in liver, serum and brain of rat inhalated with trichloroethylene. EXPERIMENTAL AND TOXICOLOGIC PATHOLOGY : OFFICIAL JOURNAL OF THE GESELLSCHAFT FUR TOXIKOLOGISCHE PATHOLOGIE 1994; 46:133-41. [PMID: 7987071 DOI: 10.1016/s0940-2993(11)80042-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Temporal variations in chronic effects of inhalated 300 ppm trichloroethylene (TCE) on the fatty acid composition in rats were investigated to clarify influences of TCE on the fatty acid metabolism of serum, liver and brain, including synaptosome, myelin and mitochondria fractions on weeks 0, 4, 8, 12 after exposure and on week 4 after rehabilitation started following 12 weeks exposure. On week 4, rats exposed to TCE had significantly lighter body weight, lighter epididymal fat pads weight and heavier liver weight compared with controls. In liver and serum, increases in 16:0, 18:0, 18:1n-9, 20:2n-6, 20:3n-6 and 20:4n-6 and decreases in 18:2n-6, 18:3n-6, 18:3n-3, 20:5n-3, 22:5n-3 and 22:6n-3 were also observed. The differences between the exposure and the control groups in the fatty acid composition in liver and serum, except for 18:1n-9 and 18:2n-6, did not enhance from week 4 after TCE exposure. In brain, significant changes of fatty acid composition caused by TCE appeared as decreases in 18:2n-6 and 22:5n-3, and increases in 20:4n-6 and 22:4n-6 during the whole exposure period. Changes of fatty acid composition in brain occurred in the same manner as in serum and liver phospholipids, except that 18:1n-9 was elevated in mitochondria. Changes in brain were slighter and appeared later than those in liver and serum. TCE had a strong effect on the fatty acid composition of mitochondria in neural cells.(ABSTRACT TRUNCATED AT 250 WORDS)
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Affiliation(s)
- T Okamoto
- Department of Environmental Medicine, Shimane Medical University, Japan
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Abstract
Evidence has been accumulating that several classes of compounds are converted by glutathione conjugate formation to toxic metabolites. The aim of this review is to summarize the current knowledge on the biosynthesis and toxicity of glutathione S-conjugates derived from halogenated alkenes, and hydroquinones and quinones. Different types of toxic glutathione conjugates have been identified in detail; (i) conjugates which are converted to toxic metabolites in an enzyme-catalyzed multistep mechanism and (ii) conjugates which serve as a transport form for toxic quinones will be discussed. The kidney is the main, with some compounds the exclusive, target organ for compounds metabolized by these pathways. Selective toxicity to the kidney is easily explained due to the capability of the kidney to accumulate intermediates formed by processing of S-conjugates and to bioactivate these intermediates to toxic metabolites. The influences of other factors participating in the renal susceptibility and influencing human risk assessment for these compounds are discussed.
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Affiliation(s)
- W Dekant
- Institut für Toxikologie, Universität Würzburg, Germany
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Miller DR, Miller LP. Acute lymphoblastic leukemia in children: an update of clinical, biological, and therapeutic aspects. Crit Rev Oncol Hematol 1990; 10:131-64. [PMID: 2193648 DOI: 10.1016/1040-8428(90)90004-c] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Affiliation(s)
- D R Miller
- Department of Pediatrics, Northwestern University Medical School, Chicago, Illinois
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Abstract
1,1,2-Trichloroethylene (TCE) is a widely used halogenated solvent, produced in hundreds of millions of kg each year for industrial purposes. Occupational and environmental exposure of human populations to TCE has been reported in industrialized areas. Long-term carcinogenicity studies in rodents demonstrate that exposure to high doses of TCE results in the induction of liver and lung tumors in the mouse, and tumors of the kidney and the testis in the rat. An indirect mechanism, based on the stimulation of liver peroxisome proliferation by TCE metabolites, was proposed to explain species differences in TCE hepatocarcinogenicity. Mutagenicity studies indicate that TCE is weakly active both in vitro, where liver microsomes produce electrophilic TCE metabolites, and also in vivo in mouse bone marrow, where high rates of micronuclei, but no structural chromosome aberrations, are found. Among TCE metabolites, trichloroacetic acid was reported to be carcinogenic to mouse liver. Furthermore, both trichloroacetic acid and chloral hydrate were found to be genotoxic in vivo, inducing structural and numerical chromosome abnormalities, respectively.
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Affiliation(s)
- R Crebelli
- Istituto Superiore di Sanità, Rome, Italy
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Nagaya T, Ishikawa N, Hata H. Sister-chromatid exchanges in lymphocytes of workers exposed to trichloroethylene. Mutat Res 1989; 222:279-82. [PMID: 2922011 DOI: 10.1016/0165-1218(89)90144-4] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
To detect mutagenic effects of trichloroethylene (TCE) on humans, sister-chromatid exchanges (SCEs) were analyzed in lymphocytes of 22 workers occupationally exposed to TCE and 22 matched controls. Although urinalysis in the workers revealed their obvious exposure to TCE, no increase in SCE frequencies was found in lymphocytes of the workers. SCE analysis in lymphocytes could not detect mutagenic effects by occupational exposure to TCE on humans.
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Affiliation(s)
- T Nagaya
- Department of Public Health, Gifu University School of Medicine, Japan
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Hobara T, Kobayashi H, Kawamoto T, Iwamoto S, Sakai T. The absorption of trichloroethylene and its metabolites from the urinary bladder of anesthetized dogs. Toxicology 1988; 48:141-53. [PMID: 3341043 DOI: 10.1016/0300-483x(88)90096-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
In order to examine the absorption of trichloroethylene (TRI) and its metabolites from the urinary bladder of dogs, we injected TRI and its metabolites, i.e., chloral hydrate (CH), free trichloroethanol (F-TCE), trichloroacetic acid (TCA) and conjugated trichloroethanol (Conj-TCE), into the urinary bladder of anesthetized dogs, and measured the agents and their respective metabolites in the blood or serum, urine and bile. The percentage of water absorbed from the urinary bladder was 10-20% 2 h after the administration of all substances. The percentage of agents absorbed was 60-70% for the TRI and TCA groups, and 50-60% for the CH, F-TCE and Conj-TCE groups 2 h after administration. The combined urinary and biliary excretion rates of the absorbed materials from the urinary bladder 2 h after administration were 46% for F-TCE, 30% for CH, 6% for Conj-TCE and 0.5-1.0% for TRI and TCA. Urinary re-excretion rates of the total excreted amounts were 65-70% in TRI, CH and F-TCE groups, about 50% in TCA and 99% in Conj-TCE group. It is possible that all of the substances administered, particularly F-TCE, are metabolized to Conj-TCE in the urinary bladder.
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Affiliation(s)
- T Hobara
- Department of Public Health, Yamaguchi University School of Medicine, Ube, Japan
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Kimbrough RD, Grandjean PA. Risk assessment: extrapolation to individual risk. BASIC LIFE SCIENCES 1988; 43:245-53. [PMID: 3365221 DOI: 10.1007/978-1-4684-5460-4_23] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Affiliation(s)
- R D Kimbrough
- Centers for Disease Control, U. S. Department of Health and Human Services, Atlanta, Georgia 30333
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Affiliation(s)
- D R Miller
- Northwestern University Medical School, Division of Hematology, Children's Memorial Hospital, Chicago, Illinois 60614
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Hobara T, Kobayashi H, Kawamoto T, Iwamoto S, Sakai T. Intestinal absorption of trichloroethylene in dogs. Toxicol Appl Pharmacol 1987; 91:256-65. [PMID: 3672525 DOI: 10.1016/0041-008x(87)90106-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
In order to examine the intestinal absorption of trichloroethylene (TRI), we developed the intestinal circulation system of dogs and administered TRI solution at three concentrations (0.1, 0.25 and 0.5%) to the three parts of the intestinal tract (jejunum, ileum, and colon) of the operated dogs. We measured TRI and its metabolites, free-trichloroethanol, trichloroacetic acid, and conjugated trichloroethanol, in serum or blood, urine, bile and circulating solutions. The absorption rates of TRI from the intestine were 50-70% of the administered volume of TRI 2 hr after administration in all groups, and all parts of intestine readily absorbed TRI. Moreover, there were no significant differences in the absorption rates of TRI and water between the jejunum and ileum, and ileum and colon, respectively. The excretion rates of TRI and its metabolites in urine and bile were very low (0.1-0.4%) compared with the volume of absorbed TRI from the intestine 2 hr after administration in all groups. The high degree of absorption of TRI should be considered when threshold limits for TRI in the drinking water, the surface water, and the ground water are established.
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Affiliation(s)
- T Hobara
- Department of Public Health, Yamaguchi University School of Medicine, Ube, Japan
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Abstract
This review discusses reasons why animal cancer tests cannot be used to predict absolute human risks. Such tests, however, may be used to indicate that some chemicals might be of greater concern than others. Possible hazards to humans from a variety of rodent carcinogens are ranked by an index that relates the potency of each carcinogen in rodents to the exposure in humans. This ranking suggests that carcinogenic hazards from current levels of pesticide residues or water pollution are likely to be of minimal concern relative to the background levels of natural substances, though one cannot say whether these natural exposures are likely to be of major or minor importance.
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Whittemore AS. Comment. J Am Stat Assoc 1986. [DOI: 10.1080/01621459.1986.10478312] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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