Chrysene, atmosphere

Photolytic. Based on structurally related compounds, chrysene may undergo photolysis to yield quinones (U.S. EPA, 1985) and/or hydroxy derivatives (Nielsen et al, 1983). The atmospheric half-life was estimated to range from 0.802 to 8.02 h (Atkinson, 1987). Behymer and Hites (1985) determined the effect of different substrates on the rate of photooxidation of chrysene using a rotary photoreactor. The photolytic half-lives of chrysene using silica gel, alumina, and fly ash were 100, 78, and 38 h, respectively. 

Under atmospheric conditions, a low rank coal (0.5-1 mm particle size) from Spain was burned in a fluidized bed reactor at seven different temperatures (50 °C increments) beginning at 650 °C. The combustion experiment was also conducted at different amounts of excess oxygen (5 to 40%) and different flow rates (700 to 1,100 L/h). At 20% excess oxygen and a flow rate of 860 L/h, the amount of chrysene emitted ranged from 127.9 ng/kg at 950 °C to 1,186.0 ng/kg at 750 °C. The greatest amount of PAHs emitted were observed at 750 °C (Mastral et ah, 1999). 

Figure 1. Gas chromatogram of PAH in a work atmosphere a, particulate PAH b, gaseous PAH. The peak identities are 1, naphthalene 2, 2-methylnaphthalene 3, 1 -methylnaphthalene 4, biphenyl 5, acenaphthene 6, dibenzofuran 7, fluorene 8, 2-methylfluorene 9, 1-methylfluorene 10, dibenzothiophene 11, phenanthrene 12, anthracene 13, methylphenanthrene/methylanthracene 14, methylphenan-threne/methylanthracene 15, 2-methylanthracene 16, 4,5-methylenephenanthrene 17, methylphenanthrene/methylanthracene 18,1-methylphenanthrene 19, fluoranthene 20, benzo(def)dibenzothiophene 21, pyrene 22, ethylmethylenephena-threne 23, benzo(a)fluorene 24, benzofb)fluorene 25, 4-methylpyrene 26, meth-ylpyrene 27, 1-methylpyrene 28, benzothionaphthene 29, benzo(c)phenanthrene 30, benzophenanthridine 31, benzo(2i)anthracene 32, chrysene/triphenylene 33, benzo(b)fluoranthene 34, benzof])fluoranthene 35, benzo(k)fluoranthene 36, ben-zo(c)pyrene 37, benzofa)pyrene 38, perylene 39, indenof 1,2,3-cd)pyrene 40, dibenz(a, /a,h)anthracenes 41, benzofghi)perylene 42, anthanthrene 43, coro-...

Humoral immunity was monitored in male iron foundry workers in Poland (Szczeklik et al. 1994). Coke oven workers (199) were compared to cold-rolling mill workers (76). The groups were similar with respect to age, length of employment, and smoking habits. The results showed that coke oven workers, exposed to high concentrations of atmospheric PAHs, including fluoranthene, perylene, pyrene, benzo[a]pyrene, chrysene, benz[a]anthracene, dibenz[a,h]anthracene, and... 

Several other studies provide evidence that atmospheric concentrations of particle-phase PAHs are higher in winter than in summer. In a 1981-82 study conducted in the Los Angeles area, atmospheric concentrations of 10 PAHs (anthracene, fluoranthene, pyrene, chrysene. benz[a]anthracene. combined benzo[a]pyrene and perylene, benzo[b]fluoranthene. benzo[k]fluoranthene. 

Figure 7.13 Results obtained for the atmospheric microwave-assisted extraction of various polycyclic aromatic hydrocarbons from contaminated soil, and comparison with those obtained from Soxhlet extraction , Soxhlet , aMAE 1, naphthalene 2, acenaphthylene 3, acenaphthene 4, fluorene 5, phenanthene 6, anthracene 7, fluoranthene 8, pyrene 9, benz[a]anthracene 10, chrysene 11, benzo[fr, ]fluoranthene 12, benzo[a]pyrene 13, indeno[l,2,3-cd]pyrene 14, benzo[gfe ]pyrene [1] (cf. DQ 7.10).

PROBABLE FATE photolysis very little specific data, but photolysis may claim some of the dissolved compound, atmospheric and aquatic photolytic half-life 4.4-13 hrs, subject to near surface, direct photolysis with a half-life of 4.4 hrs, if released to air, it will be subject to direct photolysis, although adsorption may affect the rate, reaction with photochemically produced hydroxyl radicals gives an estimated half-life of gas phase crysene of 1.25 hrs oxidation chlonne and/or ozone in sufficient quantities may oxidize chrysene, photooxidation half-life in air 0.802-8.02 hrs hydrolysis not an important process volatilization probably too slow to compete with adsorption as a transport process, will not appreciably evaporate sorption adsorption onto suspended solids and sediment is the dominant transport process if released to soil or to water, expected to adsorb very strongly to the soil biological processes short-term bioaccumulation, metabolization and biodegradation are the principal fates... 

Polycyclic aromatic hydrocarbons (PAH) in atmospheric particles have received a great deal of attention because of the known carcinogenic effects of some of these compounds. The most prominent of these compounds is benzo(a)pyrene and other examples are benz(a)anthracene, chrysene, benzo(e)pyrene, benz(e)acephenanthrylene, benzo(j)fluoranthene, and indenol. Some representative structures of PAH compounds are given as follows ... 

Polycyclic aromatic hydrocarbons are ubiquitous in the atmosphere. Maximum concentrations often occur in urban areas, resulting primarily from engine exhaust and other forms of combustion. These processes produce compoimds that may be carried across continents and oceans, particularly in highly industrialized areas of the northern hemisphere (Simoneit and Mazurek, 1981). High molecular weight PAH, such as fluoranthene, pyrene, chrysene, benz[a]anthracene, benzofluoranthenes, benzo[a]pyrene, and benzo[e]pyrene are commonly encountered in urban atmospheres (Simoneit and Mazurek, 1981). Low molecular weight PAH are also widely distributed and include unsubstituted and alkyl naphathalene, phenanthrene, acenaphthene, and fluorene. PAH react in the upper atmosphere with NO to form nitro-derivatives, which are mutagenic. 

Das et al. reported a synthetic method of chrysene framework 46 by hydrative dimerization of o-alkynylacetophenone 11 with PtCl2 catalyst in a CO atmosphere (Scheme 15.17). The tandem catalysis comprises an initial selective hydration of the alkyne, followed by chemoselective dimerization of diketone intermediates [29]. Kuznetsov and Verin reported the synthesis of chrysene framework by dimerization of benzopyrylium salts [30]. 

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