Exposure, carcinogens

WATTENBERG L (1981) Inhibition of carcinogen-induced neoplasia by sodiiun cyanate, tert-butylisocyanate and benzyl isothiocyanate administered subsequent to carcinogen exposure . Cancer Res, 41, 2991-4. 

One human carcinogenicity exposure study was located. This study did not find convincing associations between exposure to hydraulic fluid and the incidence of cancer at a specific site (Siemiatycki et al. 

For some toxicants (particularly carcinogens) exposures at any level are not permitted. These toxicants have zero thresholds. 

For applications in the diagnostics and biomarker area, 8-oxo-7,8-dihydro-2,-deoxyguanosine (8-oxoGuo) was measured as an oxidation stress biomarker in urine samples from smokers and non-smokers (Hu et al. 2006). When 100, uL of samples (10 times dilution) were used, a detection limit of 5.7 pg/mL (2.0 fmol) was achieved. The cycle time was 10 min per sample. The application was used for clinical scale. A similar approach was used for the detection of N7-methylguanine, another carcinogen exposure biomarker in human urine (Chao et al. 2005). 

Perry, P.E. and Evans, H.J. (1975). Cytoitological detection of mutagen/carcinogen exposure by sister chromatid exchange. Nature 258 121-125. 

Benowitz NL, Hall SM, Stewart S, Wilson M, Dempsay D, Jacob P 111 (2007) Nicotine and carcinogen exposure with smoking of progressively reduced nicotine content cigarette. Cancer Epidemiol Biomarkers Prev 16 2479-2485... 

The lARC has determined that there is sufficient evidence of carcinogenicity of BNA in humans and animals. Because of demonstrated high carcinogenicity, exposure by any route should be avoided. 

Arsine is a dangerously acute toxicant and a carcinogen. Exposure to 250 ppm for 30 minutes can be fatal to human. 

Zhang, et al. Evaluation of carcinogen exposure in people who used reduced exposure tobacco products. J Natl Cancer Inst 2004 96(11) 844-852. NT002 Patel, P.S., M. H. Shah, F. P. ]ha, et al. Alterations in plasma lipid profile patterns in head and neck cancer and oral precancerous conditions. Indian J Cancer 2004 41(1) 25-31. 

In view of the various possible pathways for nitrosation of amines as well as of amine derivatives (amides, ureas, carbamates, etc. ), it is not unexpected then for N-nitroso compounds to be found in many different areas of the human environment (11). It is possible that N-nitroso compounds may represent a carcinogenic exposure which most people experience on a daily basis. The list of items that have now been demonstrated to have measurable levels of various N-nitroso compounds present within them has grown considerably over the past decade (, 11, 12). A portion of this list would include air, water, soil, cheese, meats, fish, eggs. 

Ashby, J. and Paton, D. (1993) The influence of chemical structure on the extent and sites of carcinogenesis for 522 rodent carcinogens and 55 different human carcinogen exposures. Mutat. Res., 286, 3-74. 

Suspected human carcinogen exposures should be carefully limited to levels as low as reasonably achievable below the TLV. h OSHA threshold of 1500 lbs (680 kg). 

Carcinogen exposure is largely due to lifestyle, such as cigarette smoking, but occupation is an important source of exposure to carcinogens. Table 4.4 lists some occupational chemical hazards and the cancers associated with them. 

Carcinogen in mice.2 Lowest toxic doses (mice) at 2 mg/kg (subcutaneous), 4 mg/kg/15 weeks (oral) and 240 mg/kg/15 weeks (skin).3,4 Animal carcinogen reasonably anticipated to be human carcinogen. Exposure by all routes should be carefully controlled to the lowest possible levels.4... 

Syrian hamster embryo (SHE) cell transformation assay (In vitro) (SHE cells are used to evaluate the potential of a wide range of agents to induce morphological transformations. Following carcinogen exposure (1-7 days), SHE cells display a multistage pattern of neoplastic progression similar to that observed in vivo)... 

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