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High levels of perfluoroalkyl substances (PFASs) were observed in rural areas near a fluorochemical industrial park (FCIP) in the Yangtze River Delta region. The concentrations of total PFAS (∑PFASs) in soil, surface water, groundwater, and rainwater were in the range of 0.6-64.6 ng/g dry weight, 15.6-480.9, 4.8-614.6, and 13.4-542.2 ng/L, respectively. PFASs in rainwater and groundwater were higher than in surface water. The influence of the FCIP on rural soils extended to a distance of approximately 4 km based on the changes in PFAS compositions. The impact on surface water is mainly through direct river flow connected with contaminated sources, which may extend farther than 7 km in the case of unrestricted flow but much shorter distance for unconnected rivers. The penetration of PFASs in groundwater aquifers can extend as far as ca. 6 km, while direct water flow is the main transport route for PFASs. The influence radius of the FCIP can be as far as 60 km due to atmospheric precipitation.

The Yangtze River drainage basins are China’s most important economic development zones and also the locations of several large-scale fluorine chemical industries. In order to reveal the contribution from the tributaries at the dividing point between the middle and lower reaches of the Yangtze River with respect to perfluorinated substances (PFASs), 17 PFAS compounds in surface water, groundwater, and tap water samples were analyzed in the tributary system of the Jiujiang section of the Yangtze River. The total concentrations of PFASs in the surface waters ranged from 7.8 to 586.2 ng/L. High proportion of short-chain compound PFBS in surface waters in Nanchang City, Poyang Lake, and the Yangtze River was observed which is likely of WWTPs’ origin.

Compared to the low-altitude areas, high-altitude regions have low air temperature and relatively high snow precipitation. These climatological characteristics will affect the environmental behavior of persistent organic pollutants (POPs) in such a special geographical environment, leading to cold-trapping of certain POPs in these areas. Ruoergai highland prairie in the eastern edge of the Qinghai-Tibetan Plateau was selected to study the distribution characteristics of organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) in aerosols and gas phase samples collected in two seasons of 2011 and measured by isotope dilution-HRGC/HRMS method. OCPs and PCBs in the Ruoergai air were at low levels compared with the adjacent populated areas such as Lanzhou and Chengdu. Higher concentrations of POPs in aerosol and gas phase were observed in winter than in summer, showing the impact of monsoon on the transport of POPs to this region. Northwesterly winds in winter may transport OCPs and PCBs from industrial and agricultural areas in the northwestern China. HCB, α-HCH, and PCB 28 were the predominant compounds found in the air. Soil to air fugacity ratios show that Ruoergai soils behave as a secondary source of the relatively volatile compounds (HCHs, α-endosulfan, PCB 28 and 52) to the atmosphere during summer and behave as a sink of atmospheric DDTs due to the OC-rich soils as well as lower temperatures. Similar 206Pb/207Pb and 208Pb/207Pb ratios in Ruoergai aerosols to those of aerosols of Lanzhou and ores in Qinghai, Xinjiang, Kazakhstan, and Russia may indicate that the aerosol sources were mainly related to air mass passing over the neighboring regions and countries.

Perfluoroalkyl acids (PFAAs) are widely used as multi-purpose surfactants or water/oil repellents. In order to understand the contamination level and compositional profiles of PFAAs in aqueous environment in textile, leather, and paper making industrial areas, surface waters and tap waters were collected along the watershed of the Qiantang River where China's largest textile, leather, and paper making industrial bases are located. For comparison, surface water and tapwater samples were also collected in Hangzhou and its adjacent areas. 17 PFAAs were analyzed by solid phase extraction-high performance liquid chromatography-tandem mass spectrometry. The results show that the total concentrations of PFAAs (ΣPFAAs) in the Qiantang River waters ranged from 106.1 to 322.9 ng/L, averaging 164.2 ng/L. The contamination levels have been found to be extremely high, comparable to the levels of the most serious PFAA contamination in surface waters of China. The PFAA composition profiles were characterized by the dominant PFOA (average 58.1% of the total PFAAs), and PFHxA (average 18.8%). The ΣPFAAs in tap water ranged from 9.5 to 174.8 ng/L, showing PFAA compositional pattern similar to the surface waters. Good correlations between PFAA composition profiles in tap waters and the surface waters were observed.

The contamination status of perfluoroalkyl substances (PFASs) were investigated in 64 tapwater samples collected from 17 cities and 45 surface water samples from adjacent areas in the eastern China. The total PFAS concentrations in tapwater ranged from 1.4 to 175 ng/L; relatively higher PFAS levels were observed in samples collected from the Yangtze River Delta region, which was similar to the geographical distribution pattern of PFAS levels observed in rivers and lakes. The highest total PFASs in tapwater was found in Changshu, where several fluorine-related industries are located, whereas the lowest was observed in Beijing. Significant positive correlations between PFAS compositions in tap water sample and their source waters were noted. Several industries such as paper, textile, and leather industries may contribute to the contamination of PFASs in tapwater.

Environmental problems have been caused by mining of ion-absorbed rare earth in South China, where chemical pollution in soil has been the most serious issues. There are rare earth mines in Longnan, Jiangxi Provence, South China as study object, where the investigation, sampling have been carried out and all samples were tested and analyzed. The results supported that key problems of polluted soil restoration in rare earth mining area are soil bad acidification and serious NH4+-N,NO3--N,NO2--N pollution. Limited factors of polluted soil restoration of rare earth mining area are presented. It is believe that adjusting pH values and denitrifying of the polluted soil in rare earth mining area and revegetation are feasible plan for soil restoration in rare earth mining area.

Near-surface atmospheric aerosols were collected at sampling frequency of 3 d per week for one year from August 2009 to July 2010 in Laoshan District, Qingdao, located in the mid-latitude coastal region of East Asia monsoon region. The samples were analyzed for cosmogenic nuclide beryllium-7 ( 7 Be), organochlorine pesticides (OCPs), and polychlorinated biphenyls (PCBs). The annual average 7 Be concentration was 6.83 ± 0.40 mBq m −3 , with the variation range from 1.52 to 14.58 mBq m −3 . The maximum and minimum levels were observed in September and May, respectively. Autumn and spring were the seasons with high 7 Be concentrations and summer was the lowest 7 Be season. Enhanced wet precipitation may have caused lower 7 Be observed in summer when southeasterlies were prevailing. Higher 7 Be concentrations in autumn 2009 were caused by the abnormal atmospheric circulation. Concentrations of HCHs, DDTs, and PCBs followed a trend of being lower in summer and higher in winter. Higher chlorinated PCB isomers were predominant in winter and lower chlorinated PCB isomers were predominant in summer. ∑OCPs generally showed positive correlations with 7 Be but were interrupted by the “spring leak maximum” episode for 7 Be in the atmosphere in April when the stratosphere–troposphere exchange was enhanced, and in December when abnormally high HCHs were observed. No significant correlation was found between 7 Be and PCBs except for PCB28. Seasonal oscillations in 7 Be and the ratios of POP/ 7 Be were observed.

A high-volume air sampler and a high-resolution gamma-ray spectrometer have been used to measure the activity of 7Be in near-surface atmospheric aerosols at sampling frequency of 3 days week for 1 year from August 2009 to July 2010 at Beijing in the mid-latitude region of East Asia monsoon. The measurements indicate that the average concentration of 7Be was 8.39 ± 0.49 mBq m−3, which was significantly higher than values reported for other cities in the East Asia monsoon region and in the world during the same period. The maximum and minimum of the weekly means of 7Be concentration were observed in September and May, respectively. The 7Be concentrations varied in accordance with the monsoon phases. Low but frequent wet precipitation may have caused lower 7Be observed in July when southeasterly was prevailing. Higher seasonal mean of 7Be concentrations in autumn could be attributed to the abnormal atmospheric circulation in autumn 2009.

At the temperature of 18.0-22.3 degrees C, biological carriers were produce from pure SRB and zeolite by the embedding immobilized method, and a sulfate-reducing biological filter filled with filter carriers was built to treat cadmium-containing wastewater. Experimental research on removal efficiency of Cd2+, COD and SO4(2-) in wastewater by the biological filter was carried out after SRB domestication. Results show that cadmium can be removed satisfactorily from wastewater using SRB by the biological filter filled with sulfate-reducing bacteria. When the filtration rate was 0.4 m x h(-1) and the cadmium concentration in wastewater was not more than 15 mg x L(-1), the processing efficiency was the best. In the formal running period, the removal rates of Cd2+, COD and SO4(2-) by the biological filter were more than 99%, 75% and 50%. The effluent Cd2+ concentration was less than 0.1 mg x L(-1), which could meet the cadmium emission requirements in the wastewater quality standards for discharge to municipal sewers (CJ 343-2010). The removal of Cd2+, COD and SO4(2-) by biological filter mainly occurs in the top 60 cm of the filter bed during stable operation. When the filtration rate was less than 0.6 m x h(-1), Cd(2+) can be removed by the biological filter with high efficiency and stability.