Review/evaluations by government agencies: U.S. National Research Council/National Academy of Sciences (NRC, 1972, 1983, 1988); International Agency for Research on Cancer monographs (IARC, 1983, 1987, 1989); World Health Organization; Environmental Health Criteria (EHC) monographs (e.g., Diesel Fuel and Exhaust Emissions, EHC 171, WHO, 1996); U.S. Department of Health and Human Services, Public Health Services and National Toxicology Program, the Reports on Carcinogens (8th Report, U.S. DHHS, 1998); the California Air Resources Board (1994, 1997, 1998); the California EPA (1997); and the Danish Environmental Protection Agency (e.g., see Nielsen et al., 1994, 1997, 1998).
Other publications include the following: handbooks and collections of chapters on PAHs and
PACs (e.g., Bj0rseth, 1983; Grimmer, 1983b; Bj0rseth and Ramdahl, 1985; White, 1985; Howard et al., 1990; Neilson, 1998); the series Polynuclear Aromatic Hydrocarbons published by Battelle Press (e.g., see Cooke et al., 1982); monographs on polycyclic aromatic hydrocarbons (e.g., Mackay et al. 1992; and Harvey, 1997); chapters dealing with PAHs and PACs in books on atmospheric chemistry and environmental organic chemistry (e.g., in Finlayson-Pitts and Pitts (1986), Schwarzenbach et al. (1993), and Graedel, Hawkins, and Claxton (1986)); review articles on atmospheric reactions and fates of PAHs by Nielsen et al. (1983), Nielsen (1984), Nikolaou et al. (1984), Van Cauwenberghe (1985), Pitts (1987,1993a, 1993b), Baek et al. (1991), Atkinson and Arey (1994), and Arey (1998a).
outline them in Box 10.2 and give examples in Tables 10.1 and 10.2 of how they are generally employed with respect to atmospherically relevant PAHs. The nomenclature for selected N-, O-, and S-atom-functionalized PACs is described briefly in Section A.2.b and examples are found in Tables f0.3-10.5.
The same molecule may appear with different orientations. For example, in the current literature, the structure for the 3-ring PAH phenanthrene is drawn as (IVa), (IVb), or (IVc). While one or more IUPAC rules may be broken, their ring numberings are internally consistent.
Some PAHs may have two hydrogens at a specific carbon position, the Indicated hydrogens. Such an indicated hydrogen should be mentioned by carbon number, even when it is further oxidized to a carbonyl group; consider, for example, 7//-benz[c/e]anthracene (XII) and 7//-benz[<ie]anthracen-7-one (XIII, benzan-throne).
Similarly, the structure of a nitro-PAH lactone found in ambient aerosols and also formed in laboratory irradiations of phenathrene-NOx-air mixtures, 2-nitro-6//-dibenzo[6,<i]pyran-6-one, which is a powerful, direct-acting bacterial mutagen and potent human cell mutagen, is commonly shown as (XI) (Helmig et al., 1992a; Arey et al., 1992; Sasaki et al., 1995, 1997b; Arey, personal communication).
Finally, a possible source of confusion when assigning structures to a given PAH is the "correct" number of the double bonds within the fused rings. The Fries Rule states that "the most stable form of a polynuclear
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