Polycyclic Aromatic Hydrocarbons Evaluation of Sources and Effects (1983) / Chapter Skim
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3 ATMOSPHERIC TRANSFORMATIONS OF POLYCYCLIC AROMATIC HYDROCARBONS
3 ATMOSPHERIC TRANSFORMATIONS OF POLYCYCLIC AROMATIC HYDROCARBONS
Pages 97-144
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From page 97... ...
At lower SO2 concentrations more relevant to ambient pollution, PAHs do not appear to react readily with SO2. Hughes et al.37 observed no reaction between SO2 at parts-per-million concentrations and BaP or pyrene adsorbed on silica gel, alumina, and coal fly ash.
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From page 98... ...
Product studies are in good agreement, and the chemical distribution of PAR phototransformations in the adsorbed state closely resembles that obtained in the bulk-liquid phase. However, reactivity reportedly varies widely as a function of substrate, and that makes it difficult to extrapolate laboratory studies to the ambient atmosphere.
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From page 99... ...
PAHs deposited in the pure form on cellulose TLC plates exhibit short half-lives, from 23 min for anthracene to about 20 h for BaP.45 On Whatman paper, pure PAHs appear more resistant to photooxidation; egg., the half-life for perylene is about 2 d, compared with only 4 h on cellulose TLC plates. In the adsorbed state, PAHs appear to be much more resistant to photooxidation, with losses of only 10Z on soot after 48 h of irradiation.17 On fly ash, only modest photodecomposition rates (up to 20%)
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From page 100... ...
Although the evaluations of these methods are in the early stages, it was found that statistical modeling does not depend on source emission data, if the ambient-air measurement data base is large. In 1981, Daisey and Kneipl3 reported that it was possible to use multivariate regression models of ambient-air data for apportioning the contributions of emission sources to airborne particulate organic matter.
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From page 101... ...
The 1972 NRC report Particulate Polycyclic Organic Mattered estimated that heat and power generation produced BaP at SOO metric tons/yr; refuse-burning, at 600 tons/yr; coke production, at 200 tons/yr; and motor vehicles, at 20 tons/yr. BaP has often been used as a surrogate in estimating source contributions of complex mixtures of PAHs.
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From page 102... ...
The major contributors were the inefficient combustion of coal in residential furnaces, coke ovens, and refuse fires. This is in close agreement with the NRC report Particulate Polycyclic Organic Matter, which stated that 90% of the annual nationwide BaP emission was attributable to coal- and wood-fired residential furnaces, coal-refuse fires, and coke production.
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From page 103... ...
They determined that the automotive contribution to Detroit ambient BaP was only 5-42%, with typical BaP concentrations 3 times as high as in Los Angeles.
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From page 104... ...
o In ~ a, c' ~··· oron ~on p4 tar: c)
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From page 105... ...
~ o mI-, - ·~o ~ Anal 'V D C`.
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From page 108... ...
it In o ce o a' :^ 3 SO o As C)
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From page 109... ...
TABLE 3-5 Heterogeneou~ Photo-oxidation and Ozonolys is Hal f-Live~ of PAHs on TLC Platesa Half-Life, h Ozonolys is in Dark PAH Anthracene Benz ~ a ~ anthracene ~2~ -J 1.23 2.88 Dibenz ~ ah ~ anthracene 2 . 71 Dibenz ~ ac ~ anthracene 3 .82 .
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From page 110... ...
TABLE 3-6 Reaction of Adsorbed PAHs with Nitrogen Dioxide PAH-NO2 Nitro Reaction Nitro Derivative Effect of Half-life,a Derivatives Yield Substrate PAH d Identified Measured Investigated _ Phenanthrene 30 Mononitro, b isomer not specifiedb Anthracene __ 9-Nitroc ? d Fluoranthene 27 3-Nitroband b _ 8-nitrob Chrysene 26 6-Nitrob~c b c __ __ Pyrene 14 l-Nitrob,C,e 6,c,e c,e and dinitroe Benzo[a]
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From page 111... ...
TABLE 3- 7 Yields of Nitro PAHs as Function of Substratea Nitro-PAH yield, ~g/100 ~ g of PAR I-Ni troDYrene Dark UV Light Daylight Subs bate Carbon 0.45 O 38 Alumina, deactivated 2.4 2.3 Alumina, activated 1.9 2.0 Fly ash Silica gel aData from Jiger and Hanus .
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From page 112... ...
T.ABLE 3-8 Influence of Substrate on Photo-Oxidation of PAH Half-life, h, ~ Destruction in 48 hb Pure PAH on Pure PAH Loss, %, Cellulose on Whatman Adsorbed Adsorbed on PAH TLC Platea Paper on Soot Fly AshC . Anthracene Benz E a ~ anthracene 0.2 4.2 Dibenz [ate]
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From page 113... ...
k TABLE 3-9 Benzo [a Jpyrene Content of Urban Aira Benzo~a] pyrene Content, ng/m3 Location Spring Summer Fall Winter New York: Commercial 0.5-8.1 0.7-3.9 1.5-6.0 0.5-9.4 Freeway 0.1-0.8 0.1-0.7 3.3-3.5 0.7-1.3 Residential 0.1-0.6 0.1-0.3 0.6-0.8 0.5-0.7 Detroit: Commercial 7.2 -- -- 5.0-17.0 Freeway -- 4.0-6.0 3.4-7.3 9,2-13.7 Residential -- 0.2 -- 0.9-1.8 Atlanta 2.1-3.6 le 6-4 ~ 0 12-15 2.
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From page 114... ...
TABLE 3-10 At. Benzota~pyrene Concentrations in Pretoria, Johannesburg, Durban, and Other Large Citiesa Benzo[a]
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From page 115... ...
ED ~ ~ ~Go ~of e ~·· .
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From page 116... ...
soot from kerosene flame, (middle) urban air particles, and (bottom)
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From page 117... ...
Peak Identifications 2 Biphenyl 4 Acenaphthylene 8 Fluorene 10 C14H8 14 Phenanthrene 15 Anthracene . 18 Methylphenanthrene 19 4H-Cyclopenta[def]
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From page 118... ...
FIGURE 3-3 . Total PAH abundance in the various Pettaquamscut t River sediment core sections vs .
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From page 119... ...
Most structures given as examples of possible isomers. Reprinted with permission from Van Vaeck et al.;36 copyright 1980, John Wiley & Sons Ltd.
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From page 120... ...
6 -Nib ochrys ene FIGURE 3-5. Nitro products identified in heterogeneous reactions of PAN with nitrogen dioxide.
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From page 122... ...
FIGURE 3-6. Products of heterogeneous photooxidation of anthracene on atmospheric particulate matter.
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From page 123... ...
l hi, o tl At, fOT 1 1, 6-Dione ~0 3,6-Dione 11 o o 11 6, 12-Dione POOH [~C OOH ~20 A~ydride 7H-Benz He] anthracene - 7 - one 3 ~ 4 -d icarboxyl ic acid FIGURE~3-7.
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From page 124... ...
second ring, primary particulate matter introduced by man; outermost ring, secondary material formed in atmosphere. Elemental carbon added to seco22 ring.
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From page 125... ...
During baking of these electrodes, volatile components are produced from anthracite ore base. Reprinted with permission from Bjorseth; 6 copyright Ann Arbor Science Publishers, Inc.
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From page 127... ...
Component Location Total particulate mass, ug/m3 215 131 102 40 Benzene solubles. ug/m3 21.7 13.2 8.3 2.6 Lead,pg/m3 ~.35 2.50 1.97 0.50 Traffic density X 10-3,vehiCIe mi/mi2/day 200 130 95 8 PAN, ng/m3 Coronene 6.4 3.2 2.8 0.20 Pyrene 2.0 1.4 3.8 0.18 fluoranthene 1.9 0.8 3.4 0.12 "nz(~ anthracene 1.1 0.8 3.
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From page 128... ...
, 10-5 Mi/Da/Mi2 (5) 0.75 1.2 1.5 1.5 2.0 1.2 0.65 0.4 0.8 1.05 0.95- 0.95 0.9 Sample Yields, Gym' Suspended Particulate Matter Geom.
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From page 129... ...
Reactivity of polycyclic aromatic hydrocarbons adsorbed on soot particles. Atmos.
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From page 130... ...
Polynuclear Aromatic Hydrocarbons: Chemistry and Biological Effects. 4th International Symposium.
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From page 131... ...
Detection and characterization of nitro derivatives of some polycyclic aromatic hydrocarbons by fluorescence quenching after thinlayer cl~romatography: Application to air pollution analysis.
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From page 132... ...
Oxidative transformations of polycyclic aromatic hydrocarbons adsorbed on coal fly ash. Science 207:763-765, 1980.
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From page 133... ...
Theoretical considerations of the adsorption of polynuclear aromatic hydrocarbon vapor onto fly ash in a coal fired power plant, pp .
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From page 134... ...
Van Cauwenberghe. Cascade impactor measurements of the size distribution of the major classes of organic pollutants in atmospheric particulate matter.
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From page 135... ...
The purposes of this chapter are to describe the biologic activity of various kinds of polluting emission and some of their PAH components and to attempt to relate the toxic impact of such emission to its content of specific PAHs. (See Chapter 3 for discussion of particle size and respiratory uptake, Chapter 6 for discussion of PAH transfer in tissues, and Chapter 9 for recommendations.)
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From page 136... ...
reported little change in pulmonary resistance or in airway reactivity to a carbachol aerosol in conscious sheep exposed for 30 min to diesel-exhaust particles. Battigelli7 exposed human volunteers for up to 1 h to diesel exhaust at total hydrocarbon concentrations of 2-6 ppm (comparable with the environment in railroad shops)
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From page 137... ...
Laurie and Boyes97 measured the somatosensory and visual evoked potentials in control rats and rats that had been exposed to diesel exhaust during neonatal life. Although only small abnormalities were noted in the visual evoked potential, significantly longer latencies for all the peaks of somatosensory evoked potential were seen in the exposed rats.
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From page 138... ...
The numbers of lymphoid cells that produced IgM antibody to sheep red cells were determined in lymph nodes and spleen 7 d after inoculation with the sheep red cells. Only minimal or no effects on the induction of immunity were observed.
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From page 139... ...
After treatment of mice with 3-methylcholanthrene (3-MC) , dibenz~ah~anthracene, or BaP, a prolonged depression of the immune response to sheep red cells was noted; the noncarcinogens BeP and anthracene were ineffective in this regard.l07'l63 The effects of the PAHs have been reviewed by Baldwin,4 who reported a good correlation between degree of immunosuppression and carcinogenicity.
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From page 140... ...
In general, these batteries include the evaluation of three or more end points from the following list: toxic effects, mutagenesis, DNA damage and repair, chromosomal alteration, and neoplastic transformation. TOXIC EFFECTS Toxicity is usually manifested by such end points as cell death, increase in generation time, decrease in respiration, decrease in rate of macromolecular synthesis, and release of particular cell-bound proteins.
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From page 141... ...
Examples of genetic markers that use mutagenesis as the end point are given in Table 4-5. The bacterial systems are best exemplified by the Salmonella typhimurium test strains developed by Ames et al.3 This system measures the reversion rate to histidine prototrophy in five test strains that carry specific frameshift and base-pair substitutions at the his locus and a series of mutations at the other loci to make the bacteria more sensitive to chemically induced mutation.
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From page 142... ...
Such cells as C3HlOTl/2 and BALB/3T3 have also been used in mutagenesis studies; these cells have easily detectable hydrocarbonmetabolizing activity.36~92 However, they are hypotetraploid, may not detect some recessive mutations, and may not detect some mutations that are expressed codominantly.95 These cells express a high degree of contact inhibition and low saturation density and thus can be used in bioassays of neoplastic transformation. Recent studies have suggested that such cells can be used to detect simultaneously the mutagenic and transforming capacities of test chemicals.35 Primary cell strains and in vivo-derived cells have been used in mutagenesis assays; although they have high PAH-metabolizing capacities and are diploid, the difficulty in growing, handling, and evaluating data from these mixtures of cells is an important disadvantage.120 DNA DAMAGE AND REPAIR Assays for DNA damage and repair have also used both bacterial and mammalian cells.
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From page 143... ...
The second method involves the incorporation of 5-BUdR into lymphocyte cultures during mitogen-induced activation in vitro; this has been used in the human studies mentioned above. Good baseline data on the incidence and variation of SCE in humans now exist.l8 SCE has also been shown to persist for several days or even months after~chemical exposure and thus can serve as an index of acute or chronic exposure to chemicals.94~118~161 Comparison of rates of formation of SCE and specific ON.A adducts suggests that, for several types of mutagens, induction of SCE does not necessarily result from a single specific ONA lesion.166 CHROMOSOMAL ABERRATION Assays for chromosomal aberration are also used to monitor for the mutagenic activity of test chemicals.
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From page 144... ...
cell strains,42, 29 established aneuploid rodent cell lines,36~43~64~84 cell lines derived from human tumors,80~138 and cell lines initiated from apparently healthy human tissue.50~85~113~154 Table 4-7 compares properties of some mammalian-transformation systems. These cell lines share the following properties to some degree: They exhibit density-dependent inhibition of cell division and reach a defined saturation density, do not form colonies on soft agar or agarose, and do not give rise to tumors when inoculated into immunosuppressed syngeneic hosts.
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