Analysis Of Volatile And Semivolatile Organic Pollutants In Drinking Water With Huangpu River As Water Source

Solid-phase extraction followed by gas chromatography with mass spectrometric detection(SPE-GC/MS) has been widely applied for trace and ultra-trace analysis of organic chemicals in various environmental samples.While adsorbents with different characteristics are combined in series,organic chemicals can be enriched at large, avoiding the problem of unintegrity when a single adsorbent is used to enrich chemicals in water samples.When raw water was treated by a series of technique processes including enhanced coagulation,precipitation and filtration,the amount of organic pollutants in drinking water is usually at trace level.To assure the accuracy and reliabilty,a high effective pretreatment technique is needed to satisfy the aquirement of high sensitivity of GC/MS techniques.As for the complexity of organic pollutants in drinking water,and the limitation of insufficient adsorption of using a single adsorbent,this study combined in series of XAD-2,PSDVB and activated carbon which were usually used to adsorb and enrich chemicals with low-polarity,medium-to-high polarity and those with broad-spctrum polarity,and establish an effective and integrated pretreatment technique to adsorb organic pollutants in water samples to the largest scales.And this pretreatment technique followed by GC/MS was applied for the analysis of volatile and semi-volatile organic pollutants in drinking water.The GC/MS detection conditions referred to the EPA525.2 method of the United States.Part One Determination of Detection Method for Volatile and Semi-volatile Target ChmicalsVolatile and semi-volatile organics in water were selected as target chemicals according to the list of EPA priority organic pollutants and our previous results in this project,including pesticides,hormones and fungicides,phthalate esters and adipic acid esters,polychlorinated biphenyls,polycyclic aromatic hydrocarbons,ethers, phenols,amines,etc.A GC/MS detection method from EPA525.2 method was referred to to analyze the standard solutions of these target chemicals.Result showed that the GC/MS method could simultaneously detect 93 target chemicals and 5 surrogates.The linearity is good within the range of detection.The range of optimum linearity was between 0.1 ng/μL and 10ng/μL.The retention times of all target chemicals and surrogates were stable and the control charts showed that each chemical was in control in the analysis period.Part Two Establishment of Solid-phase Extraction Method for Volatile and Semi-volatile Target ChemicalsXAD-2,PSDVB and activated carbon were combined in series to adsorb organic pollutants in drinking water samples which were fortified with all target organics and surrogates.Four issues were evaluated.(1) the efficiency of the enrichment system,(2) the performance of different adsorbents,(3) the overload of the enrichment system, and(4) the effect of eluting solvents.Result showed:(1) The recovery efficiency was good for most target chemicals using the extraction method established in this study; (2) PSDVB and activated cabon could adsorb those which could not be effectively adsorbed by XAD-2;(3) At the fortified level of 20μg of each target chemical to 40L ultra-purity water,the system for enrichment didn't occur to overload for pesticides, ethers,polychlorinated biphenyls,polycyclic aromatic hydrocarbons,amines, hormones and fungicides.Some organics such as phthalate esters and 2,6-di-tert-butyl-4-phenol were still detectable in followed XAD-2,PSDVB and activated carbon as the overload judge system.The laboratory reagent blank showed the existence of these chemicals,suggesting that the existence of these chemials in the overload judge system might be caused by the background;(4) For XAD-2,most target chemicals were desorbed by methanol:acetone(7:3,v/v),while acetone:hexene (1:1,v/v) and dichloromethane could desorb those chemicals which couldn't be sufficiently desorbed by methanol:acetone(7:3,v/v).Therefore,the eluting solvents for the adsorbates in XAD-2 are to be furtherly screened.For PSDVB,hexene and dichloromethane had little desorption effect for those which couldn't be sufficently desorbed by methanol:ethyl estate(1:1,v/v).For activated carbon,dichloromethane could desorb some chemicals which couln't be sufficiently desorbed by acetone:hexene(1:1,v/v),while the desorption effect of methanol and ethanol was very weak.Part Three Analysis of Organic Pollutants in Drinking Water with Huangpu River as Water SourceIn order to evaluate the feasibility and effectiveness of the solid-phase extraction/GC/MS method established in this study,it was applied for organic analysis of the fresh water fromYangshupu waterwork which based on Huangpu River as water source.Under the restriction condition of match level more than 50%to the USA NIST standard spectrum,43 organic chemicals were detectable in drinking water, there are 8 chemicals in the list of EPA priority pollutants,including isophorone which is a kind of pesticide,dimethyl phthalate,diethyl phthalate,di-n-butyl phthalate, bis(2-ethylhexyl)phthalate,and three kinds of polycyclic aromatic hydrocarbons which included naphthalene,phenanthrene and pyrene.Meanwhile,8 organics belong to regulated catagery in the standards for drinking water quality(GB5749-2006) in China,including atrazine which is classified as triazine herbicide,diethyl phthalate, di-n-butyl phthalate,bis(2-ethylhexyl)phthalate,bis(2-ethylhexyl)adipate,naphthalene, phenanthrene and pyrene.Among these chemicals,the concentrations determined for atrazine,dimethyl phthalate,diethyl phthalate,di-n-butyl phthalate, bis(2-ethylhexyl)phthalate,bis(2-ethylhexyl)adipate,naphthalene,phenanthrene and pyrene were 0.324,0.005,0.032,0.281,0.165,0.032,0,017,0.088,0.0001μg/L, respectivly.The total amount of naphthalene,phenanthrene and pyrene was 0.1501μg/L,and other polycyclic aromatic hydrocarbons were not detectable,so the total amount of total polycyclic aromatic hydrocarbons didn't excess the regulated value which is 2μg/L in standards for drinking water quality(GB5749-06),the concentration of all of the quantitable pollutants which are in the list of standards for drinking water quality(GB5749-2006) in China in this study didn't excess the regualated value.Though other chemicals detected are not on the United States Environmental Protection Agency(US EPA) priority pollutant list and not belong to the standards for drinking water quality(GB5749-2006) in China,they still need to be concerned for the detection at high frequency and a relatively high concentration.The department for water supply,environmental protection and health supervisor should pay attention to pollutants both in the list of priority pollutants in US EPA and the standards for drinking water quality(GB5749-2006) in the ministry of health in China,and other organic pollutants.