The carcinogenicity of various polynuclear aromatic hydrocarbons has generally been demonstrated by their ability to act as complete carcinogens in the development of cancers in rodent skin tests. In order to develop proposed acceptable concentration levels for various PAHs in drinking water, we reviewed the studies that formed the basis for determining that these specific PAHs were carcinogenic in animals. We found that the relative potency of these PAHs varied over a range of many orders of magnitude. For example, the carcinogenic strength of benz[a]anthracene (BaA) is found to be about 1/2000th that of benzo[a]pyrene (BaP). We have used the calculated carcinogenic potency of the various PAHs relative to that of BaP as a means for proposing specific acceptable concentration levels in drinking water for each of the specific PAHs. BaP is the only carcinogenic PAH for which EPA has published an acceptable concentration level based on carcinogenicity. Based on the level EPA set for BaP (0.028 micrograms/liter), this methodology has provided for the specific PAHs a determination of proposed acceptable concentration levels quantitatively based on the same data that were used to qualitatively determine them to be animal carcinogens. We have proposed acceptable concentration levels for the carcinogenic PAHs in drinking water that range from 0.03 micrograms/liter for BaP to 6.5 micrograms/liter for BaA. We recommend that acceptable concentration levels for the various PAHs be based on their relative carcinogenic potencies rather than the EPA method of using the potency of only one specific PAH, BaP, to serve as the exposure level determinant for all PAHs. We further suggest that this methodology may be applicable to other classes of carcinogenic compounds. We have also found useful for the determination of acceptable concentration levels for the noncarcinogenic PAHs an analogous methodology based on the relative toxicities of the noncarcinogenic PAHs.

Hi sunnygirl or is it copygirl,

Plagiarising the USA Government's health information now that is pretty brave. When you steal you have to supply a note saying that you have taken their property or they will get angry with you,ie leave their name on it and don't pretend it is your work.



PubMed
U.S. National Library of Medicine
National Institutes of Health

Regul Toxicol Pharmacol. 1989 Jun;9(3):273-83.
Comparative carcinogenicity of the PAHs as a basis for acceptable exposure levels (AELs) in drinking water.
Rugen PJ, Stern CD, Lamm SH.

Consultants in Epidemiology and Occupational Health, Inc., Washington, DC 20007.
The carcinogenicity of various polynuclear aromatic hydrocarbons (PAHs) has generally been demonstrated by their ability to act as complete carcinogens in the development of cancers in rodent skin tests. In order to develop proposed acceptable concentration levels for various PAHs in drinking water, we reviewed the studies that formed the basis for determining that these specific PAHs were carcinogenic in animals. We found that the relative potency of these PAHs varied over a range of many orders of magnitude. For example, the carcinogenic strength of benz[a]anthracene (BaA) is found to be about 1/2000th that of benzo[a]pyrene (BaP). We have used the calculated carcinogenic potency of the various PAHs relative to that of BaP as a means for proposing specific acceptable concentration levels in drinking water for each of the specific PAHs. BaP is the only carcinogenic PAH for which EPA has published an acceptable concentration level based on carcinogenicity. Based on the level EPA set for BaP (0.028 micrograms/liter), this methodology has provided for the specific PAHs a determination of proposed acceptable concentration levels quantitatively based on the same data that were used to qualitatively determine them to be animal carcinogens. We have proposed acceptable concentration levels for the carcinogenic PAHs in drinking water that range from 0.03 micrograms/liter for BaP to 6.5 micrograms/liter for BaA. We recommend that acceptable concentration levels for the various PAHs be based on their relative carcinogenic potencies rather than the EPA method of using the potency of only one specific PAH, BaP, to serve as the exposure level determinant for all PAHs. We further suggest that this methodology may be applicable to other classes of carcinogenic compounds. We have also found useful for the determination of acceptable concentration levels for the noncarcinogenic PAHs an analogous methodology based on the relative toxicities of the noncarcinogenic PAHs.


PMID: 2756174 [PubMed - indexed for MEDLINE]
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[Fundam Appl Toxicol. 1993]
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Cheers