Genotoxic Polycyclic Aromatic Hydrocarbons Research Articles

GC and GC-MS analysis of polychlorinated dioxins, dibenzofurans and aromatic hydrocarbons in fly ash from coal-burning works

Carcinogenic and genotoxic polycyclic aromatic hydrocarbons (PAHs) were detected in coal fly ash samples. Further analysis of these samples also revealed the presence of highly toxic polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs). The amount of PCDD/PCDF detected were in the parts per trillion (ppt) levels. Although coal fly ash contains a large number of organic compounds, the levels of PCDD/PCDF detected were two to three orders of magnitudes less than what has been observed in municipal solid waste incinerator (MSWI) fly ash samples. To investigate the probable reason for low levels of PCDD/PCDF in coal fly ash samples, catalytic activity tests were conducted using C-13 pentachlorophenol as the precursor. Results indicate that the formation mechanism of PCDD on coal fly ash is analogous to that on MSWI fly ash.

Drosophila wing-spot test: improved detectability of genotoxicity of polycyclic aromatic hydrocarbons

The somatic mutation and recombination tests (SMART) using eyes or wings in the fruit fly Drosophila melanogaster are flexible and sensitive systems for the detection of genotoxicity of individual chemical compounds and complex mixtures. It is of special interest that adults and larvae possess cytochrome P-450-dependent activation systems able to metabolize most promutagens, e.g., nitrosamines, aflatoxins, pyrrolizidine alkaloids, safrole, etc. The polycyclic aromatic hydrocarbons (PAHs) represent a class of promutagens poorly detectable in Drosophila genotoxicity systems. Therefore, new tester strains for the wing-spot test were constructed by introducing chromosomes 1 and 2 from a wild-type strain with increased cytochrome P-450-dependent metabolism linked to a gene on chromosome 2. Previous investigations with the new strains showed their increased detection capability for diethylnitrosamine. Comparative tests with the 3 PAHs benzo[ a]pyrene, benz[ a]anthracene and 7,12-dimethylbenz[ a]anthracene demonstrate, in a reproducible way, that with the new strains all 3 can be detected as active genotoxic compounds. The dose-response curves for all compounds show a plateau with higher exposures. This is interpreted as indicative of a saturation of the cytochrome P-450-dependent activation systems.

Urinary 1-hydroxypyrene as an indicator of human exposure to ambient polycyclic aromatic hydrocarbons in a coal-burning environment

Urinary 1-hydroxypyrene of residents of Beijing, Shenyang and Taiyuan, and workers at two coke plants, a steel plant and control groups was determined using high pressure liquid chromatography. Polycyclic aromatic hydrocarbons (PAHs) of airborne particulates from these cities and coke plants were analyzed using GC-MS; chromatogram profiles, from which 15 chemical compounds were quantified, were similar. The percentage of pyrene and benzo[ a]pyrene in PAHs was fairly constant. Statistical analysis showed significant correlation of urinary 1-hydroxypyrene with the concentration of pyrene and benzo[ a]pyrene in the ambient PAHs; the correlation coefficient was 0.978 and 0.959, respectively. It is suggested that urinary 1-hydroxypyrene can be used as a biological monitoring index for human exposure to genotoxic PAHs from the burning of coal.

Chromosome aberrations in cultured central mudminnow heart cells and chinese hamster ovary cells exposed to polycyclic aromatic hydrocarbons and sediment extracts

1. Genotoxicity experiments were conducted with cultured fish cells to determine if the high frequency of epidermal papillomas observed in lemon sole from Sturgeon Bank, where a sewage treatment plant discharges, could be correlated with contamination of the sediments with chemicals such as 3,4-benzopyrene. 2. The frequency of chromosome aberrations was measured in cultured Umbra limi heart (U1-H) and Chinese hamster ovary (CHO) cells following exposure to the polycyclic aromatic hydrocarbons (PAH) 3,4-benzopyrene (BP), 1,2,5,6-dibenzanthracene (DBA), 1,2-benzanthracene (BA), and pyrene (PY), activated using S9 prepared from rainbow trout liver. 3. An increase in the chromosome aberration frequency was only observed following exposure to fish S9-activated BP in both cell lines. 4. Following exposure of the cells to both Sturgeon Bank and Spanish Bank sediment extracts, it was determined that a higher level of toxic and genotoxic activity was associated with the Sturgeon Bank sediments. 5. Since the detection of PAH genotoxicity requires the presence of S9, and since a higher level of genotoxic activity was noted following sediment extract exposures with no S9 present, this suggests that the extracts contain a complex mix of chemicals, some of which express genotoxic activity. 6. An assessment using the micronucleus test failed to indicate in vivo genotoxicity in fish collected from Sturgeon and Spanish Banks. 7. It was, therefore, difficult to associate the observed sediment genotoxicity with the previously noted high incidence of epidermal papillomas in lemon sole from this area.