Sensitivity Analysis of PM_2.5-Bound Total PCDD/Fs-TEQ Content: In the Case of Wuhu City, China

摘要

During 2015–2017, the atmospheric PM_(2.5), PM_(2.5)/PM_(10), PCDD/Fs, PCDD/F phase distribution and PM_(2.5)-bound total PCDD/Fs-WHO_(2005)-TEQ content in Wuhu and Bengbu were investigated in this study. In addition, the sensitivity analysis for PM_(2.5)-bound total PCDD/Fs-WHO_(2005)-TEQ of Wuhu was also studied. During 2015–2017, the three-year average PM_(2.5) concentration in Wuhu was 53.0 μg m~(–3), and in Bengbu was 61.4 μg m~(–3); the results also showed the annual average PM_(2.5) concentrations of these two cities had declined, but the levels were still far above the WHO annual PM_(2.5) standard (10 μg m~(–3)). In addition, in Wuhu, the PM_(2.5)-bound total PCDD/Fs-WHO_(2005)-TEQ contents in summer (0.166 ng-WHO_(2005)-TEQ g~(–1)) were approximately only 68.8% in magnitude lower than the average value of other three seasons (0.532 ng-WHO_(2005)-TEQ g~(–1)), and that of Bengbu in summer (0.187 ng-WHO_(2005)-TEQ g~(–1)) was approximately 66.7% in magnitude lower than the average value of other three seasons (0.561 ng-WHO2005-TEQ g~(–1)). Sensitivity analysis showed that the PCDD/F concentration was the most positively correlated sensitive factor for PM_(2.5)-bound total PCDD/Fs-WHO_(2005)-TEQ, and when ΔP/P was changed from 0% to +50%, ΔS/S responded from 0% to +106%. The second positively correlated sensitive factor was PM_(10) concentration, and when ΔP/P was changed from 0% to +50%, ΔS/S responded from 0% to +72%. This was followed by atmospheric temperature, and its effect was negatively correlated, when ΔP/P was changed from –50% to +50%, ΔS/S responded from +73% to –112%. The last sensitive parameter was PM_(2.5) concentration, with the impact divided into two stages: when ΔP/P was changed from 0% to+70%, ΔS/S responded from 0% to +33%, but when ΔP/P was changed from +70% to +100%, ΔS/S responded from +33% to +25%.The results of this study provide useful information that can be used to achieve more insights into both atmospheric PM_(2.5) and PCDD/Fs.