Carcinogenesis occupational

Symposium on Toxicology, Carcinogenesis, and Human Health Effects of 1,3-Butadiene (265). Detailed comparisons of various personal monitoring devices are available (266), and control of occupational exposure to 1,3-butadiene has been reviewed (267). ... 

Huff JE, McConnell EE, Haseman JK, et al. 1988. Carcinogenesis studies results of 398 experiments on 104 chemicals from the U.S. National Toxicology Program. In Maltoni C., Selikoff I.J., ed. Annals of the New York Academy of Sciences. Living in a Chemical World Occupational and Environmental Significance of Industrial Carcinogens. Vol. 534, New York, NY New York Academy of Sciences, 1 -30. 

Observations from the field of occupational medicine also created interest among biologists in the field of experimental carcinogenesis -the laboratory study of cancer development - that is the topic of Chapters 5 and 6. 

Most of the data located concerning the health effects of heptachlor and heptachlor epoxide in humans come from case reports and occupational epidemiology studies of workers engaged either in the manufacture or application of pesticides. There is some information on people who have consumed heptachlor-contaminated food or dairy products, but no adverse health effects have been related to these exposures. The occupational studies involve exposures that are predominantly inhalation with contributions from dermal exposure, whereas all the animal studies were conducted using oral or intraperitoneal exposures. The occupational and case reports provide no quantitation of dose or duration of exposure, which makes it impossible to determine with any precision the effect levels for humans. There are no data that indicate that heptachlor or heptachlor epoxide are carcinogenic to humans. However, human studies are limited by the long latency period of carcinogenesis and by ascertainment and follow-up biases. 

Stokinger HE Occupational carcinogenesis. In Clayton GD, Clayton FE (eds) Patty s Industrial Hygiene and Toxicology, 3rd ed, rev, Vol. IIB, Toxicology, p 2893. New York, Wiley-Interscience, 1981... 

PTFE implanted subcutaneously in animals has induced local sarcomas, suggesting a foreign body reaction rather than chemical carcinogenesis the lARC has determined that there is insufficient evidence to assess the carcinogenic risk, especially with regard to occupational exposure in humans. ... 

It has been postulated that sulfuric acid may produce tumors by direct genotoxic effects of lowered pH or may promote carcinogenesis by inducing chronic tissue irritation. lARC has determined that there is sufficient evidence that occupational exposure to strong inorganic acid mists containing sulfuric acid is carcinogenic to humans. ... 

Spiegelhalder, B. and Preussmann, R. (1983). Occupational nitrosamine exposure. 1. Rubber and tyre industry, Carcinogenesis 4,1147. 

However, the mathematics describes an idealized situation, and the real situation in vivo may not be so straightforward. For example, with carbon monoxide, as already indicated, the toxicity involves a reversible interaction with a receptor, the protein molecule hemoglobin (see chap. 7 for further details of this example). This interaction will certainly be proportional to the concentration of carbon monoxide in the red blood cell. However, in vivo about 50% occupancy or 50% carboxyhemoglobin may be sufficient for the final toxic effect, which is cellular hypoxia and lethality. Duration of exposure is also a factor here because hypoxic cell death is not an instantaneous response. This time-exposure index is also very important in considerations of chemical carcinogenesis. 

Nagano, K., Nishizawa, T, Yamamoto, S. Matsushima, T. (1998) Inhalation carcinogenesis studies of six halogenated hydrocarbons in rats and mice. In Chiyotani, K., Hosoda, Y Aizawa, Y, eds, Advances in the Prevention of Occupational Respiratory Diseases, Amsterdam. Elsevier, pp. 741-746... 

K., Enomoto, M. Sakabe, H. (1994) Two-year toxicological and carcinogenesis studies of 1, 4-dioxane in F344 rats and BDFl mice. Drinking studies. Proceedings on the Second Asia-Pacific Symposium on Environmental and Occupational Health, Environmental and Occupational Chemical Hazards (2), Kobe University, pp. 193-198... 

Chovil AC. 1979. Occupational lung cancer and smoking a review in the light of current theories of carcinogenesis. Chem Manuf Assoc J 121 548-555. 

M. Sorsa in H. Vainio, M. Soria, and K. Hemminki, eds., Occupational Cancer and Carcinogenesis, Hemisphere Publishing Corporation, Washington,... 

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