The total ILCR values were
The total ILCR values were summarized by the addition of ingestion, dermal and inhalation. But the contribution of inhalation is nearly million times less than those by ingestion or dermal, and it can hardly influence the total ILCR values. Actually, the cancer risk of inhalation of soil through the mouth and nose cannot be overlooking. Moreover, the traditional approach to PAHs inherently hypothesized that the ILCR of all PAHs were additive eﬀects in a mixture. But the supra-additive and synergistic eﬀects were also possible due to metabolic augmentation (Hermann, 1981). Therefore, above defects should be overcome to as-sess the cancer risk for human beings by rule and line in the future.
In this study, the surface soils were collected from the Shanxi pro-vince of China and analyzed for PAH levels, probable sources and the potential cancer risk. The total concentrations of 15 priority PAHs showed that the heavily contaminated areas were mainly located at Datong, Xinzhou, Changzhi, and Linfen areas. Moreover, the diagnostic ratios suggested that the combustion was the predominant PAHs pol-lution sources in the surface soil. Finally, the potential human cancer risks were estimated by the ILCR model based on BaPeq for the in-dividual PAH as additive eﬀects. The results indicated that the ILCR values were greater than 1 × 10−6 in 16 of 33 sites and followed a decreasing trend of adulthood > childhood > adolescence. Especially, the significantly higher cancer risk occurred at Datong and Xinzhou areas (n = 3, p < 0.05). These results will urge the local government to weaken the coal consumption and turn to the clean Exendin-4 for protecting human health.
This work was financially supported in part by the Scientific and Technical Innovation Foundation of the Higher Education Institutions of Shanxi province, China (2017172); the Development Program for Innovative Team of “1331 Project” of Shanxi Province (201817); the Development Program for Innovative Team of “1331 Project” of Jinzhong University (201707); and the Startup Foundation of Doctors
of Jinzhong University (0001590). We thank all the students from ap-plied chemistry 1501 of Jinzhong University for assistance in soil col-lection.
Appendix A. Supplementary data
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