Carcinogenicity of PAH

Finally, it is important that further research be carried out on the identification and mechanism of action of environmental cocarcinogens and tumor promoters which can enhance the carcinogenicity of PAH. Human exposure to at least trace amounts of PAH is unavoidable. The probability of eventual tumor development may be controlled primarily by repeated exposure to cocarcinogens or promoters. 

The carcinogenicity of PAH with relativelyTigh IP, such as benzo[c]phenanthrene, benz[a]anthracene, chrysene, 5-methyl chrysene and dibenz[a,h]anthracene (Table I), can be related to the formation of bay-region diol epoxides catalyzed by monooxygenase enzymes (j>). However, the most potent carcinogenic PAH have IP < ca. 7.35 eV. 

Carcinogenicity of PAHs, Cancer Potencies, and Potency Equivalence Factors... 

Table 14.3 Critical structural features which can affect the carcinogenicity of PAHs.

Studies on PAHs are largely conducted with specific compounds. For example, many studies that explore the uptake and elimination of PAHs in marine organisms deal with naphthalenes, a major component of petroleum, and carcinogenic PAHs, such as benzo[a]pyrene. Petroleum spills are important acute events hence, it is important to understand the processes that control the bioaccumulation of naphthalene and related compounds. Understanding the mechanics of chronic exposure to PAHs from urban areas is also desirable when assessing the population structure of marine organisms and the possibility of contaminant transfer to humans. Additionally, the carcinogenicity of PAHs is an important concern because some PAHs are biotransformed to reactive metabolites that can interact with DNA. 

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