| Environmental hormone is a class of chemical compounds in environment. It may affect human and wildlife on their normal endocrines, cause reproductive, developmental and behavioral disorder. Phthalic acid esters (PAEs) are an important group of environmental hormone. Their main applications are as plasticizers in the manufacture of plastics. In recent years, large amount of plastics have caused a wide distribution of PAEs into environment. PikEs become one of the most prevalent contaminants. Eight phthalic acid esters (DEP, DPrP, BBP, DBP, DAP, DCHP, DHP, DEHP) have been studied in this paper, which are environmental hormone. PAEs are slightly soluble in water, which make it necessary to pretreatment before determination. Solid phase extraction (SPE), arising at the beginning of 70s, is a new developed pretreatment technique. The method combines isolation and enrichment, especially suitable for the water sample. Eight phthalic acid esters were extracted from water samples using solid phase extraction on HLB cartridge(200mg,6mL), a new production of Waters corporation. Several main factors in SPE were optimized by orthogonal design. The optimum condition and procedure of SPE were established as following: adjust pH of water sample to 7 before pretreatment, activate cartridge using 6mL 5% methanol in ether, 6mL methanol and 6mL distilled water respectively, control sample loading rate at 5mL/min, eluting rate at 1.0mL/min, select 9mL 5% methanol in ether as eluting solvent, 5mL 5% methanol in water as washing solvent, dehydrate the eluate by anhydrous sodium sulfate, dry it by passing nitrogen, dilute to l mL with methanol. The precision and accuracy were studied, recoveries of eight phthalic acid esters were between 75.1% and 115.5%, relative standard deviation(RSD) were between 0.9% and 2.2%. A method for the determination of eight phthalic acid esters of environmental hormone in water had been developed, which was achieved by gradient elution reversed-phase liquid chromatography with UV-detection at 224nm. The limits of detection were between 0.10 μ g/L and 0.62μ g/L. Linear correlation coefficient (r) was good, which was over 0.999. The detection and qualification rate of PAEs in wastewater and surface water had been studied. PAEs were detected in 97.4 percent of wastewater samples and 80 percent of surface water samples. The order of detection rate, from high to low, was DEHP, DBP, BBP, DEP, DCHP in wastewater, and BBP, DBP, DEHP in surface water. The concentrations of PAEs in wastewater were low to the wastewater discharge standard, but the result was not the same in surface water. The qualification rate of DBP in surface water was 35.0% and DEHP was 70.0%. Major sources of PAEs contaminations in Beijing area had been considered, in which 38 wastewater samples had been analyzed. Twenty surface water samples collected from several rivers in Beijing area had been determined. The pollution of surface water, urban and industrial wastewater in Beijing area had been learned from the analytical datas. Three phthalates (BBP, DBP, DEHP) were main contaminants in chemical wastewater. High levels of PAEs in some chemical plants wastewater caused heavy contamination. Low concentration of DBP was detected in metallurgical wastewater and BBP was found in printed wastewater. There were different levels of DEP, BBP, DBP, DCHP, DEHP in the four sewage treatment plants influents, but in effluents the levels of BBP and DEHP were lower than the value of stipulated by government. Three phthalates (BBP, DBP, DEHP) were found in hospital wastewater at lower stipulated level, but high levels of them in hospitalwashing wastewater. The presence of phthalates in rivers was the same as wastewater , which were BBP, DBP and DEHP. It indicated that some rivers had been heavily polluted by the high levels of phthalates.
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