Blood products carcinogenicity studies

Butadiene, a major commodity chemical used in the production of synthetic rubber, is listed as one of 189 hazardous air pollutants under the 1990 Clean Air Act Amendments. Butadiene is a carcinogen in rats and mice, with mice being substantially more sensitive than rats. The extent to which butadiene poses risk of cancer to humans exposed to this chemical is uncertain. The data include in vitro studies on butadiene metabolism using tissues from humans, rats, and mice as well as experimental data and physiological model predictions for butadiene in blood and butadiene epoxides in blood, lung, and liver after exposure of rats and mice to inhaled butadiene (Bond et al., 1996). 

Because there are few data on the results of human exposure to actinides, the health effects of these radioelements are more uncertain than those discussed above for ionizing radiation, radon, and fission products. Americium accumulates in bones and will likely cause bone cancer due to its radioactive decay. Animal studies suggest that plutonium will cause effects in the blood, liver, bone, lung, and immune systems. Other potential mechanisms of chemical toxicity and carcinogenicity of the actinides are similar to those of heavy metals and include (i) disruption of transport pathways for nutrients and ions (ii) displacement of essential metals such as Cu, Zn, and Ni ... 

Sassafras oil, sassafras bark, and safrole (80% of the oil) are prohibited by the FDA as food additives and flavorings because of their carcinogenic properties. A safrole-free extract is available on the market, but studies have shown that the product still produces tumors in rats (Tyler, 1993). Nevertheless, sassafras is touted in herbal home remedy books and continues to be available in health food stores. Sassafras still enjoys a reputation as a spring tonic, stimulant, anti spasmodic, blood purifier, and sudorific (sweat producer), and as a cure for rheumatism, skin diseases, syphilis, typhus, and dropsy (congestive heart failure) (Tyler, 1993). Unfortunately, sassafras seems to be nothing more than a folk medicine for more than 200 yr it has been known to be without therapeutic utility (Tyler, 1994). 

The metabolism of BaP has been studied in various human cell systems including skin epithelial cells, pulmonary alveolar macrophages, and blood monocytes and lymphocytes (7, 135, 180, 205, 365, 418), Epithelial cells metabolized BaP to dihydrodiols, phenols, and quinones in a pattern which differed from that formed by rat liver microsomes. The 7,8-dihydrodiol was formed in appreciable quantities. Pulmonary alveolar macrophages also metabolized BaP to the 7,8-dihydrodiol and converted both BaP and the 7,8-dihydrodiol to products mutagenic to Chinese hamster V79 cells. The proximate carcinogen 7,8-dihydrodiol was also formed by blood monocytes and lymphocytes along with varying amounts of the other dihydrodiols, quinones, and phenols. Monocytes... 

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