Distribution And Source Analysis Of Typical Perfluorinated Compounds In The Eastern China And The Grand Canal

Perfluorinated compounds(PFASs) are artificial synthetic Fluorine-containing compounds, which are used widely in industry and human lives for decades. In the meantime they are also persistent organic pollutants that can cause cancer, malformation and mutation. After entering the environment, they can reach remote areas as far as the polar region with the global circulation of air and water. Their half-life period is relatively long, and endanger human health by their bioaccumulation and bioconcentration. Therefore, the contamination of PFASs has caught great attention at home and abroad.In this paper, samples from Eastern China and the Great Canal are studied for 17 aimed PFASs, using HPLC- ESI-MS method. As the background area, concentrations level of rural area in Eastern China are valued. The impact of fluorine chemical industry on its surrounding environment is discussed, as well as the spatial distribution regularities of the surface water in the Great Canal being detected. This paper also briefly deduces the possible source of the contaminant. Major research result are as follows:The concentration values of FASs in the surface water of Eastern China are from 7.0 to 489.1 ng/L with an average of 77.1 ng/L. The main perfluorinated compounds detected are PFOA, PFHxA and PFBA, with exceptions of high proportion of PFOS in individual regions such as Taicang, Tai’an and Tianjin. This is possibly related to the different urbanization level in these places. If we ignore the surface water from Changshu, which is highly effected by local fluorine chemical industry, the concentration of PFASs shows a gradually decreasing trend from south to north. In the research area of Eastern China, the detection rate and concentration are much higher in surface water than ground water, and the main PFASs are PFBA, PFOA and PFOS; while within the fluorine chemical industrial zone, the concentration of PFCAs in ground water is higher than in surface water, which may be caused by the infiltration of PFASs from the river into ground water due to high ground water table near Yangtze River. But, on the whole, the concentrations of PFASs in soil sampled from Eastern China are low, which is between 0.22 to 54.6 ng/g (dry weight), with an average of 3.21 ng/g (dry weight). The fluorine chemical industrial zone in Changshu is regarded as the most heavily polluted area. With the increase distance from the industrial zone, concentration of PFASs decreases. During the rainy season (April), the concentration of PFOA may exceed that of PFOS. It is also suggested that, the sources of PFASs in rural area are primarily domestic sewage and atmosphere precipitation, after the comparison of the characteristic values of different PFASs groups in rural environmental media.Further more, in this paper, the impact on environment of fluorine chemical industry which is a typical source of PFASs pollution is interpreted. The main PFASs released from chemical plants are PFOA, PFHxA and PFPeA. Through comparative analysis of the composition of PFASs in rain water sampled from Changshu, rural district of Taicang and Beijing, we found that atmospheric long-range transport dominates the polluting process from chemical plants to its surrounding environment by PFASs. Also, the main PFASs contributed by leather industry are PFOA, PFHxA and PFBA, which accords with textile and paper manufacturing industry. The PFASs from those industrial zone with high concentration certainly will have impact on adjacent water systems. So as to evaluate the quality of drinking water, ground water samples from those areas are determined. The result shows that the drinking water is barely influenced by the chemical plants. Even so, the contamination is still at intermediate level and allows no optimism, compared with ground water sampled from other places. It also shows prominently linear correlation of PFASs concentration between surface water and tap water, thus explains the effect on the concentration by surface water on tap water. In addition, the removal rate is hardly high enough during the treatment of raw water in water supply and purification plant. After the analysis of pollution sources of surface water and tap water by ratio method of key compounds of PFASs near industrial zone, it can be concluded that the source is mainly inter-dilution of industrial pollution and atmospheric deposition.The concentration values of ∑PFASs in the surface water of Grand canal are from 6.59 to 202.51ng/L with an average of 44.4ng/L, the main perfluorinated compound detected is PFOA. The concentration of perfluorinated compounds gradually decreases along the Grand Canal from south to north spatially. In the southern watershed of the Grand canal divided by the Yangtze River, perfluorinated compounds pollution is mainly due to leather and textile industry. There is a relatively high concentration of C4 perfluorinated compounds in all of the Grand Canal water samples, indicating that the use of short-chain instead of long-chain perfluorinated compounds has a certain effect.The concentrations and compositions of the surface water among different lakes along the Grand Canal and the Grand Canal itself are very different. The detection rate of long-chain perfluorinated compounds in lakes is higher than those in the Grand canal, it may be on account of the algae in lakes will absorb PFOA and PFOS to some extent. The concentration and composition of PFASs are different in the North and South of the Lake Taihu, reflecting that the.pollution of Wuxi to Taihu is lower then that of Suzhou.However, the concentration of perfluorinated compounds is relatively high in tap water samples of Hangzhou, Haining, Suzhou and Changshu, which attention should be paid to. And, the concentration and composition of PFASs in tap water and lakes are similar, it may be as a result of the low efficiency of PFASs removal in conventional process.