[Occurrence, Distribution, Source, and Health Risk Assessment of Polybrominated Diphenyl Ethers in Surface Soil from the Shen-Fu Region, Northeast China].

The Shen-Fu region is an important urban area in northeast China. We report on a study of the distribution of polybrominated diphenyl ethers (PBDEs) in representative topsoil from this region. In the summer of 2016, 72 soil samples from three cities (Shenyang, Fushun, and Shen-Fu New City) were collected, which covered four land use types:urban, rural residential, cultivated, and woodland. We report on the concentrations, compositions, and distributions of 14 PBDEs in soil and explore their sources, and additionally undertake human exposure analysis and health risk assessments. The results showed that the concentration of ∑14PBDEs in the topsoil ranged from 0.279-50.719 ng·g-1(dry weight), with a mean of (10.466±9.246) ng·g-1. The concentrations of PBDEs was ranked for the cities as:Fushun > Shenyang > Shen-Fu New City > background, and for different land use types as:urban land > rural residential land > cultivated land > forest. Deca-PBDE had the highest proportion of all congeners, accounting for 81.25%-89.23% of all PBDEs. Source analysis indicated that commercial Deca-PBDE was the main source, contributing 66.06% of the total Deca-PBDE according to principal component analysis/multiple linear regression (PCA-MLR). Among five different age groups assessed for exposure, children in Fushun had the highest exposure dose:(20.98±25.01) ng·(kg·d)-1. In terms of different land types, the highest exposure dose was for children living in urban areas:(18.54±20.27) ng·(kg·d)-1. The non-oncogenic health risks in the Shen-Fu region are of a relatively low level.

[Pollution Characteristic and Risk Assessment of Polycyclic Aromatic Hydrocarbons in the Groundwater of Shen-Fu New City in the Hunhe River Basin].

To protect the safety of water used by the residents in Shen-Fu New City, which is undergoing the process of urbanization, 49 groundwater samples were collected along the Hunhe River Basin and 16 US EPA priority control polycyclic aromatic hydrocarbons (PAHs) were analyzed. The occurrence, distribution characteristics, sources, and potential health risk of drinking the groundwater were also assessed in this study. The results show that PAHs were detected in all samples. The concentration of PAHs ranges from 4.38 to 2005.02 ng·L-1, with an average value of (414.64±526.13) ng·L-1. Based on the comparison of the concentration level with that of other regions, the results in this study indicate a higher pollution level. The 3-4 ring PAHs are dominant; the average value was (190.93±238.96) ng·L-1 and (140.01±234.69) ng·L-1, respectively, accounting for 80% of the total PAHs. The distribution of PAHs in the groundwater is affected by the land use types. The concentration of PAHs is higher when the land use type is cultivated land, while it is lower when it is forest land. The source of PAHs was identified using Principal Component Analysis-Multiple Linear Regression (PCA-MLR). It was revealed that 36.26% of the PAHs are due to incomplete combustion of petroleum and gas, 32.72% are due to coal combustion, 28.17% originate from petroleum spills, and 2.87% are due to traffic emissions. The cancer risk levels releated to drinking the groundwater range from 5.55×10-10 to 5.65×10-6 and 13.60% of the values is in the range of 10-6-10-4. The levels are higher than the baseline of the acceptable risk, indicating the potential cancer risk. More attention should be paid to the quality of the groundwater.

[Sources and Risk Assessment of Polycyclic Aromatic Hydrocarbons from the Urbanization Process of Topsoil].

To study the effects of urbanization on concentration, sources, and health risks of polycyclic aromatic hydrocarbons (PAHs), 95 topsoil samples were collected from Liaoning Province. For this assessment, 21 PAHs were analyzed via gas chromatography-mass spectrometry and discussed. The results show the total concentrations of the 21 PAHs in background, Shen-Fu, Shen-Yang, and Fu-Shun were 1496.76 µg·kg-1, 3000.50 µg·kg-1, 8705.11 µg·kg-1, and 8178.90 µg·kg-1, respectively, which is positively correlated with the urbanization levels. Diagnostic ratios and PMF modal analysis indicate that the sources of the PAHs in soils were most likely coal combustion and traffic combustion (petroleum combustion). The main sources of PAHs in the four areas were petrochemical combustion (41.0%), coal combustion (64.4%), traffic combustion (67.5%), and traffic combustion (62.0%), that is, with the urbanization process, human activity (mainly traffic combustion) gradually become the major contributor of PAHs to the environment. Health risk assessment showed that the risk of cancer exposure through soil digestion and skin exposure was higher. There is a higher health risk from PAHs in urban soils, and the health risks associated with children and adolescents are greater than with other residents, requiring more attention.