The Pollution Analysis And Assessment Of Phthalate Acid Esters For The Zhuzhou Section Of The Xiangjiang River

Phthalate esters(PAEs) are one of the environmental hormones, which possess mutagenicity, carcinogenesis and teratogensis. Be mainly used as plasticizers of plastics, PAEs are one of synthesized organ ic compounds which have large production and wide application scope in the world at present. In recent years, large quantities of plastics have caused an extensive distribution of PAEs into environment. PAEs become one of the most widespread contaminants. As an important industrial city and transport hub of Hunan province, Zhuzhou is also an important port city of Xiangjiang River. So, it is great significance to the research of the distribution and ecological risk assessment of the environment of PAEs in Zhuzhou section of the Xiangjiang River for offering basic data and future prevention and cue.Four PAEs [Dimethyl Phthalate (DMP), Diethyl Phthalate (DEP), Butyl benzyl phthalate (BBP), Dibutyl Phthalate(DBP)] have been studied in this paper, which are environmental disruptors. The concentrations of these four PAEs in the samples of water and sediment in Zhuzhou section of the Xiangjiang River have been detected. The main theses of this research are as follows:1) An dispersive liquid-liquid microextraction method was developed for extracting four PAEs in water with extraction solvent of dichloromethane and dispersive solvent of methanol. Orthogonal test was used for studying the major elements on the recovery of extraction four factors:extraction volume (mL), dispersion volume (mL), centrifuging time (min) and centrifuging speed (rpm), and the optimum conditions are established as following:extraction volume of 45μL, dispersion volume of 0.7mL, centrifuging time of 10min, centrifuging speed of 4000rpm.2) Ultrasonic extraction are used as pretreatment for analyzing four Phthalate esters (PAEs) for sediment samples and the optimum conditions are built as following:petroleum ether and acetone(3:1) took as the extraction solvent, the extraction time of 20min.3) A high performance liquid chromatograph analytical method for the discrimination of four PAEs in water had been developed. Experiments were performed under the condition of flow posture with methanol water of 85:15 and detected with a photodiode array detector at 224nm. The linear ranges of DMP and DEP were between 0.5 to 1000mg/L, and the linear ranges of DBP and BBP were 2 to 1000mg/L. The linear correlation moduli were higher than 0.999.The lowest detection restrictions were between 0.21 to 0.51μg/L.4) Water and sediment Samples from Xiangjiang River had been investigated. The results showed that the concentration in water samples were less different in the Xiangjiang River. According to the criterion value of Environmental Quality Standards in China for Surface Water, the standard of DBP was 3μg/L.35 water samples were sampling in the testing process, DBP content analyzed of 26 water samples conform the standard, the over standard rate of DBP were 26%. The concentration in the samples of sediment was relatively high in several sampling points and became smaller with the increasing water. The concentration of PAEs from sediment in study area was as much as several times to other areas.5) According to the monitoring data, the ecological risk assessment and health risk assessment were performed for Zhuzhou section of the Xiangjiang River. The zebra fish embryo and algae were selected as receptor, the evaluating values of DMP, DEP and DBP stay in the extension of low potential ecological risk for fish embryo; the assessing values of DBP resided the range of low potential ecological risk and DMP, DEP had no ecological risk for algae. The total health risk of 3 PAEs to the individual person per yea of 3 PAEs through drinking was lower than the maximum tolerable value (5.0×10-5a-1) recommended by ICRP through health risk assessment. So the study area might have lower health risk through drinking for human. In a word, the PAEs which was studied in paper had no ecological risk and health risk. But the relevant departments still should be concerned about the trend and provide effective prevention measures.