Study On Residue Detection Methods And Risk Assessment Of Tristyrylphenol Ethoxylates Pesticide Adjuvant In The Environment

Tristyrylphenol ethoxylates(TSPEOs)are a class of non-ionic surfactantthat are widely used as adjuvants in pesticide formulations.Toxicity studies have shown that TSPEOs have subchronic toxicity and teratogenicity.Moreover,its intermediate metabolites may induce estrogen activity,acute toxicity and growth inhibition.Due to their variety in applications,most of them may end up in different environmental compartments and threat heavily to ecological environments and human health.The main aim of the present work,therefore,is to obtain TSPEOs residue concentration in water and agricultural soil.Consequently,the aim of the present study was to develop a rapid and sensitive analytical method for simultaneous identification and quantification of TSPEOs oligomers in water and agricultural soil.According to risk assessment method recommended by United States Environmental Protection Agency,ecological environment of TSPEOs were identified.(1)Solid phase extraction(SPE)and liquid chromatography-tandem massspectrometry(LC-MS/MS)residue analysis method was established for 24TSPEOn(n=6-29)in water.Thetechnique could be used to determine the concentration of 24 TSPEOn(n=6-29)in water after the optimization of pretreatment and instrument conditions.TSPEOn oligomers(n=6-29)showed satisfactory linearity with coefficients of determination(R~2)between 0.9970-0.9999.The average recovery of TSPEOn(n=6-29)analyzed by HPLC-MS/MS ranged from 70.0%to 103.3%with the relative standard deviation(RSD)of 0.7%-12.8%.The limits of detection(LOD)and quantification(LOQ)were0.002-0.25 ng/L and 0.007-0.83 ng/L,respectively.(2)An analytical method based on selective pressurized liquid extraction(SPLE)and liquid chromatography-tandem mass spectrometry(LC-MS/MS)for the determination of 24 TSPEOn(n=6-29)in soil was established.Methodsa mixed solution of dichloromethane and methanol(1:2,V/V)was selected as extract solvent,the recovery was 72.2%-110.2%with RSDr of 1.1%-14.1%and RSD_Rof 0.5%-10.0%.The linearities ofthe matrix-matched standard calibrations were satisfactory with coefficients of determination(R~2)≥0.9968 and the LOD and LOQ were 0.0004-0.019μg/kg and 0.012-1.025μg/kg,respectively.(3)This study collected and analyzed 10 water samples in Qing River and 21 water samples in Laizhou Bay of Shandong Province.The results showed that TSPEOn(n=6-29)was detected in all samples and the total concentration of∑TSPEOn(n=6-29)was 0.04-56.78 ng/L in Qing River and 0.04-131.05 ng/L in Laizhou Bay.The residual concentration of TSPEOn(n=6-29)in water in Laizhou Bay was significantly higher than that in Qing River.(4)60 soil samples in Yunnan and Chongqing were collected and analyzed.TSPEOn(n=6-29)was detected in all soil samples.The total concentration of∑TSPEOn(n=6-29)was 4.03-332.27μg/kg and 0.08-40.45μg/kg in Yunnan and Chongqing,respectively.There were significant differences between the residual concentrations of TSPEOn(n=6-29)in different regions.(5)On the basis of the above TSPEOn(n=6-29)exposure study and in combination with the toxicity data of TSPEOn(n=6-29)published so far,a preliminary ecological risk assessment of TSPEOn(n=6-29)in the above sampling area was conducted by using the risk quotient method.The results show that ecological risks of TSPEOn(n=6-29)in water can be neglected.Ecological risks of agricultural region can be neglected.