Carcinogenic Chemicals uptake

There are almost no data available concerning the pharmacokinetics (i.e., the uptake, distribution, metabolisms, and excretion) of chemical carcinogens in humans. Nevertheless, it is possible to make limited assumptions about the pharmacokinetics of carcinogens, based on the results of animal studies conducted with various chemicals, notably polycyclic hydrocarbons such as benzo[a]p3nene. 

A chemical agent may alter the absorption of a cancer causing chemical at the point of entry or at the level of cellular uptake, can alter carcinogenicity. An example of altered absorption may be found in the latency period in the development of subcutaneous neoplasm by the same dose of benzo(rst) pentaphene applied in different vehicles. The latency period was 16 weeks in peanut oil, 37 weeks in lipoprotein, and 62 weeks in Ringer s solution (16). Likewise,... 

If the chemical to be analyzed is toxic, rather than simply carcinogenic, the O2 uptake of the bacteria will decrease. This effect is easily determined and is discussed in greater depth later. 

Several components of tobacco smoke are known to be syneigistically carcinogenic with each other. These include PAHs and catechol [124] and cigarette tar and nitric oxide [125]. Tobacco use, however, is always associated with exposures to other chemicals via environmaital uptake, eating, and occupation. Several studies have demonstrated that the combinalion of tobacco smoking and exposure to other identifiable chemicals results in unanticipated and oihanced carcinogenic effects. Examples of these follow. 

The level of concern for health hazards frequently depends on the chemical form of the metal compounds. This is primarily because the critical influence of chemical form on the uptake of inhaled, ingested, or skin-deposited materials, and can result in substantially different exposure limits for different compounds. For example, the ACGIH TWA TLV for exposure to chromium compounds is most restrictive for insoluble hexavalent chromium compounds (0.01 mg/m ), which are poorly removed from lung following inhalation less restrictive for water-soluble hexavalent compounds (0.05 mg/m ), which are more readily absorbed into the bloodstream following inhalation and least restrictive for the less-reactive trivalent chromium compounds and chromium metal (0.5 mg/m ) (11). Chromic acid and chromate aerosols can be caustic to mucous membranes, and some water-insoluble chrome IV compounds are carcinogens. In addition,... 

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