a b s t r a c tPerfluoroalkyl acids (PFAAs) are emerging contaminants that have raised great concern in recent years. While PFAAs manufacturing becomes regulated in developed countries, production has been partly shifted to China. Eight fluoropolymer manufacturing facilities located in the South Bohai coastal region, one of the most populated areas of China, have been used to manufacture PFAA-related substances since 2001. The environmental consequence of the intensive production of PFAAs in this region remains largely unknown. We analyzed 17 PFAAs in twelve coastal rivers of this region, and found staggeringly high concentrations of perfluorooctanoic acid (PFOA) ranging from 0.96 to 4534.41 ng/L. The highest concentration was observed in the Xiaoqing River which received effluents from certain fluoropolymer facilities. Principal component analysis indicated similar sources of several perfluoroalkyl carboxylic acids (PFCAs) in all rivers, which indicated that atmospheric transport, wastewater treatment and surface runoff also acted as important supplements to direct discharge to surface water.
In the present study, we investigated concentrations and composition profiles of perfluoroalkyl substances (PFASs) in surface water from the Daling River in different seasons. The highest concentration of ΣPFASs (9540 ng L −1 ) and dominant homologues were found in surface water collected in summer. Perfluorobutanoic acid (PFBA), perfluorobutane sulfonate (PFBS), and perfluorooctanoic acid (PFOA) were the dominant PFASs in four seasons with a total contribution of over 90 %. The discharge of two fluorine chemical industry parks was predicted to be the main contamination source of PFASs in the study area. The daily and annual mass flows were calculated according to data of detected PFAS concentrations and water discharge, and the annual mass loading of PFASs into the Bohai Sea from the Daling River reached to 461 kg year −1 . Hazard assessment indicated that concentrations of PFASs in study area had little risk to aquatic organisms and wildlife. However, the multiple health risk would be relatively high if the water was served as drinking water in the study area.
After global commercialization of short-chain perfluoroalkyl acids (PFAAs) as substitutes to conventional long-chain PFAAs by the major manufacturers, two fluorine industry parks for production of short-chain PFAAs located in the Daling River Basin of northern China have developed rapidly in the last few years. This study provides a systematic assessment of sources, emissions, transportation, and potential risks of the PFAAs in this area. The C4 perfluorobutane sulfonic acid (PFBS) and perfluorobutanoic acid (PFBA) were the predominant short-chain PFAAs in river water, with maximum concentrations of 2.90 and 1.35 μg/L, respectively. Park 1 equipped with a telomerization process was identified to be the source of linear and branched mixtures of PFBS, PFBA, and perfluorooctanoic acid (PFOA), while park 2 with an electrochemical fluorination process (ECF) was identified to be the source of linear and branched mixtures of PFBS and PFOA. Partition coefficients between water and sediment were consistent for C4-C8 perfluoroalkyl carboxylic acids (PFCAs) but directly proportional to C9-C11 PFCAs and perfluoroalkyl sulfonic acids (PFSAs). Analysis on the health risk of PFBS and PFBA suggested that they were not without risk since short chain PFAAs are known to be recalcitrant during water treatment.
a b s t r a c tShort chain perfluoroalkyl acids (PFAAs) have been developed since 2002 by the major manufacturers to replace the conventional C8 and higher homologues, with much of the world production shifted to China in recent years. In this study, we conducted a continuous monitoring program over the period 2011 e2014 with seasonal monitoring in 2013 for PFAAs emitted from two rapidly developing fluorochemical industry parks located in the Daling River Basin, Northern China. The trend of PFAA contamination was identified, dominated by perfluorobutane sulfonic acid (PFBS), perfluorobutanoic acid (PFBA) and perfluorooctanoic acid (PFOA), with the maximum concentrations of 3.78 mg/L, 3.70 mg/L, and 1.95 mg/L, respectively. Seasonal monitoring uncovered the occasional emission of perfluorooctane sulfonic acid (PFOS). Construction trends of new facilities and associated manufacturing capacity of the main products were also analyzed to assess correlations with PFAA emissions. An assessment of the data over the period 2011e2014 found a positive correlation with fluorocarbon alcohol (FCA) production and emission of PFAAs. Groundwater and tap water around the main source indicated that the dominant PFAAs had different diffusion behaviors. PFBS levels were higher in surface water, while PFBA was dominant in groundwater and tap water, with PFOA levels being higher in downstream groundwater. Considering the continuous expansion and development of fluorochemical industry in the Daling River Basin, this study will provide abundant information on the effectiveness of risk assessment and management.
In the long history of disease prevention and treatment, ancestral populations worldwide have gained knowledge and experiences in traditional medicines. For instance, ethnomedicines of Chinese ethnic minorities constitute an important part of traditional medicines. In our study, we firstly clarified the concept of ethnomedicines and the connotations of ethnopharmacology. The particularity of ethnomedicine research were then summed up, and the development profiles of the ethnomedicines of Chinese ethnic minorities were discussed by investigating the current status and existing problems. On this basis, we abstracted the innovative development path of ethnomedicines for the first time, which was found to follows:resource study ! standardized development research ! industrialization of the achievements and efforts for internationalization. We found that platform establishment and team training are keys to achieving innovative development. Hence, this study provided a basis for ethnomedicine development.
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