Although the health effects of individual PAHs/PNAs are not exactly alike, 17 PAHs/PNAs have been identified as being of greatest concern with regard to potential exposure and adverse health effects on humans and are thus considered as a group (profile issued by the Agency for Toxic Substances and Disease Registry). These 17 PAHs/PNAs are Acenaphthene; Acenaphthylene; Anthracene; Benz(a)anthracene; Benzo(a)pyrene; Benzo(e)pyrene; Benzo(b)fluoranthene; Benzo(ghi)perylene; Benzo(j)fluoranthene; Benzo(k)fluoranthene; Chrysene; Dibenz(ah)anthracene; Fluoranthene; Fluorine; Indeno(1,2,3-cd)pyrene;