Cancer known carcinogens

Martin CN, MeDermid AC, Gamer RC. 1978. Testing of known carcinogens and noneareinogens for their ability to induee unseheduled DNA synthesis in HeLa cells. Cancer Res 38 2621-2627. 

There is no conclusive evidence from epidemiological studies that mercury increases cancer risk in humans. In the few studies in which increases have been reported, concomitant exposure to other known carcinogens has confounded the results. The lARC has determined that there is inadequate evidence in humans for the carcinogenicity of mercury and mercury compounds. In animals there is inadequate evidence for carcinogenicity of metallic mercury and limited evidence for the carcinogenicity of mercuric chloride. 

An increased risk of death from bladder cancer (33 vs. 22.7 expected) was reported in 40,000 rubber and cable workers who had mixed exposures to many rubber additives, including PBNA, but not to known carcinogens. In contrast to this study, no significant increases in overall or site-specific cancer was detected in a cohort of 2410 rubber chemical manufacturing workers, who were employed at a factory in north Wales, United Kingdom, between 1955 and 1984. ... 

Other types of studies summarized include experiments in which the agent or mixtme was administered in conjunction with known carcinogens or factors that modify carcinogenic effects studies in which the end-point was not cancer but a defined precancerous lesion and experiments on the carcinogenicity of known metabolites and derivatives. 

Based on current evidence, the International Agency for Research on Cancer (IARC) has stated (IARC 1984) that the available epidemiological studies provide limited evidence that certain exposures in the aluminum production industry are carcinogenic to humans, giving rise to cancer of the lung and bladder. A possible causative agent is pitch fume. It is important to emphasize that the potential risk of cancer in the aluminum production industry is due to the presence of known carcinogens (e.g., PAHs) in the workplace and is not due to aluminum or its compounds. 

Toxicity Benzidine is a well-known carcinogen in animals and humans. It has been classified by the IARC as a group 1 carcinogen. Workers exposed to benzidine have demonstrated increased risk of bladder cancer.67... 

Chromium(VI) RfD (oral) Oral cancer classification Carcinogenic risk from inhalation exposure Inhalation cancer classification 3x1 O 3 mg/kg/day D—not classified 1.2x1 O 2 pg/m3 A—known human carcinogen IRIS 2000b... 

Whether any one of the contaminants or mixture of contaminants of food introduced by cooking, if any, is responsible for some cancers is not currently known and awaits further research. What is clear is that cooking food in certain ways will introduce known carcinogens, such as polycyclic aromatic hydrocarbons, heterocyclic amines, and acrylamide into our diet. By avoiding this style of cooking any risk can be minimized. 

Even when animals are given significant doses of potent known carcinogens, however, not all develop tumours, even inbred mice, due to biological variation in the various factors and stages required for development of a tumour. Humans show much greater variation, and therefore the incidence of cancer could be much lower on the whole, although some individuals could be more sensitive. 

Two other chemicals and one mixture failed this initial screen benzene, 1,3-butadiene, and VOCs. Benzene is a known carcinogen. It poses a one-in-a-million excess cancer risk at a concentration of 0.12 /rg/m for a lifetime exposure. Air modeling results show the concentration of benzene at the refinery boundary is 2.0 At the nearest residence, this concentration is 1.5 jug/m. 1,3-... 

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