Occurrence and impact of polychlorinated dibenzo-p-dioxins/dibenzofurans in the air and soil around a municipal solid waste incinerator

To assess the influence of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans（PCDD/Fs） on the environment in the vicinity of municipal solid waste incinerators（MSWIs）, we determined the levels of PCDD/Fs in air and soil samples collected around a MSWI, which is the largest in China. The International Toxicity Equivalency Quantity（I-TEQ） concentrations of PCDD/Fs in air samples were from 0.0300 to 1.03 pg I-TEQ/m^3（0.445–13.6 pg/m^3）, with an average of 0.237 pg I-TEQ/m^3, while in soil samples they ranged from 0.520 to 3.40 pg I-TEQ/g（2.41–88.7 pg/g） with an average of1.49 pg I-TEQ/g. The concentrations of PCDD/Fs in air and soil samples were comparable to other areas, and Pe CDFs were the dominant contributors, which was different from stack gas homologue patterns. Multivariate statistical analysis showed that PCDD/Fs emission from the MSWI did not directly affect the profiles of PCDD/Fs in air and soils, so that vehicles and unidentified emission sources should be considered. The daily inhalation levels of PCDD/Fs for children（0.0110 to 0.392 pg I-TEQ/（kg·day） and adults（0.00600 to 0.221 pg I-TEQ/（kg·day） near the MSWI were lower than the tolerable daily intake of 1.00 to 4.00 pg WHO-TEQ/（kg·day）, but in winter the values were higher than in summer. These results can be used as basic data for assessing the risk of PCDD/Fs exposure in residents living around this MSWI, and more monitoring programs and studies should be carried out around MSWIs.