Tioxic and genotoxic evaluation of the airbone nitro-PAHs using Microtox and Mutatox test

• Main Authors: Hsi-Tsung Lin, 林錫聰
• Other Authors: Ta-Chang Lin
• Format: Others
• Language: zh-TW
• Published: 2001
• Online Access: http://ndltd.ncl.edu.tw/handle/51954022709116584902

碩士 === 國立成功大學 === 環境工程學系 === 89 === Nitrated polyciclic aromatic hydrocarbons (nitro-PAHs) are of concern due to their direct mutagenic activity and carcinogenicity. Their toxicity has been found to be far greater than that of unsubstituted polycyclic aromatic hydrocarbons. The semivolatile organic compounds collected from the ambient air was fractionated according to polarity to five fractions. Among them the majority of nitro-PAHs was found in fraction III. This study was to investigate the acute toxicity and genotoxicity of nitro-PAHs by MicrotoxTM assay and MutatoxTM assay. Microtox results show that some of the nitro-PAHs standards exhibited low acute toxicity. In MutatoxTM assay, nitro-PAHs standards were primarily found to be direct-acting mutagenic. We further subfractionated fraction III, which contained nitro-PAHs, into four subfractions. In gas-phase extracts, subfraction III-2 and III-3 contained the majority of the nitro-PAHs. While in particulate-phase extracts, most nitro-PAHs were found in subfraction III-3 and III-4. The direct-acting mutagenicity was found in subfractions which contained nitro-PAHs. It is proposed that nitro-PAHs contributes the main direct-acting mutagenicity. In urban atmosphere, the crude extract of fraction III was shown to be more toxic than the sum of the four subfractions in both gas-phase and paticulate-phase extract . This implies that synergistic effects are involved in the acute toxicity in fraction III. Finally, the genotoxicity data did not parallel the Microtox results in this study, indicating that potentially long-term genotoxic agents may not be revealed by short-term toxicity assays.