| Abstrakt: |
Probabilistic risk assessment was conducted to evaluate health risks caused by eight volatile organic compounds (VOCs) (benzene, toluene, xylene, ethylbenzene, styrene, formaldehyde, acetaldehyde, and acrolein) in five commuting modes (car, air-conditioned bus, non-air-conditioned bus, subway, and bicycle) in Guangzhou. Monte Carlo method and the contribution to variance method were applied to obtain the more scientific evaluation results and the more influential variables. The results revealed that the carcinogenic risk of air-conditioned bus and car were the highest, followed by bicycle, non-air-conditioned bus, and subway. The probability of the risk exceeding 10-6 was approximately 90%, 62%, 62%, 91%, and 92%, respectively. Moreover, the noncarcinogenic risk of air-conditioned bus and car were the highest, followed by non-air-conditioned bus, bicycle, and subway. It indicated that subway, non-air-conditioned bus, and bicycle are better commuting choices for city dwellers to reduce health risks and alleviate traffic pressure. Formaldehyde, benzene, and acrolein contribute to a significant proportion in health risk and should be the prior controlled organic pollutants. Sensitivity analysis suggests that exposure time is the most influential parameter for carcinogenic and noncarcinogenic risk, followed by concentrations of VOCs in air and exposure duration. [ABSTRACT FROM AUTHOR] |
