| Environment endocrine disruptors (EEDs),also called environmental hormone, may modify the normal functioning of human and wildlife endocrine systems and cause developmental, behavioral and reproductive problems. Phthalic acid esters (PAEs) are important groups of environmental hormone. They are mainly used as plasticizers in the plastical manufacture. In recent years, with the widely using plastics, PAEs have been coming into environment. PAEs are becoming one of the most prevalent contaminants.The analysis of PAEs in environment (e.g., water, air, soil, wastes, and biota including both plants and animals) is critical not only for regulatory monitoring them but also for learning their distribution, transportation, migration and their ultimate degradation in the environment. Because of the minim content of PAEs in the environment, some manipulation process such as concentration and purification needed to satisfy the results.Six phthalic acid esters (DMP, DEP, DBP, DIBP, BBP, DEHP), which are environmental hormone, have been studied in this paper. Six phthalic acid esters were extracted from water samples using Supelco Visiprep TM DL-12 anti-pollution devices, solid-phase extraction Accubond C18 (200mL/3mL) columns and dichloromethane as eluant. Orthogonal test was used for evaluating the major impact on the recovery of the solid phase extraction four factors: eluant volume (mL), elution rate (mL/min), sample rate (mL/min) and the pilot cleaning agent. The impacts of four solid-phase extraction factors on the six kinds of phthalate acid esters were studied and the best conditions of solid-phase extraction for each target compounds were optimized. The optimum condition and procedure of SPE were established as following: pH value of 7, sample rate of 5mL/min, a rate of elution 1.0mL/min, elution volume of 4mL, cleaning agents water: methanol (80:20).MSP-6600 microwave extraction device and the low toxicity of the extraction solvent solution mixture with acetone and n-hexane were used for trials.Orthogonal test was used for a major impact on the recovery of the microwave extraction four factors: the volume of solvent extraction, extraction time, the extraction pressure and extraction power tests. The impacts of four microwave extraction factors on the six kinds of phthalate acid esters were studied and the best conditions of microwave extraction for each target compounds were optimized. The optimum condition and procedure of ME were established as following: acetone/hexane(1:1) used as the extraction solvent, extraction volume of 15mL, the extraction time of 15min, 0.2MPa pressure extraction and extraction power 70%.A method for the determination of six phthalic acid esters of environmental hormone in water were developed, which was achieved by gas chromatography. The linear ranges of PAEs were between 1 to 500mg /L. The linear correlation coefficients were better than 0.99 and the lowest detection limits were between 0.40 to 4.58mg /L. PAEs were detected in 100 percent of park surface water samples. The concentration order, from high to low, was DIBP,BBP,DEHP,DEP,DMP,DBP.The qualification rates of DBP and DEHP in park surface water were 41.7% and 75.0% respectively. The pollution of phthalate esters in water environment in Beijing's park were analyzed. Dibutyl phthalate(DBP), butyl benzyl phthalate ester(BBP), double-phthalate (2-ethylhexyl) ester(DEHP) were detected in water of park and butyl benzyl phthalate ester(BBP), double-phthalate (2-ethylhexyl) ester (DEHP), Diethyl phthalate(DEP) were detected in sediment of park.Phthalate ester compounds pollution were mainly caused by poor water quality upstream source of pollution, water shortage, management problems, poor water flow, the unreasonable design of bank protection, pollutants into the water and the water ecosystem destruction. For the above reasons, some control measures were also discussed in this paper.
|
PDF Full Text Request