Investigation Of Pollution And Ecological Risk Assessment On Poiycyclic Aromatic Hydrocarbons (PAHs) In The Water From Lake Chaoho

Objective：To investigate the pollution characteristics of16EPA priority controlpolycyclic aromatic hydrocarbons (PAHs) of Chaohu, including naphthyl (Nap),acenaphthene (Ace), acenaphthylene (Acy), fluorenyl (Flu), phenanthrene (Phe),anthracene (Ant), fluoranthene (Fla), pyrene (Pyr), benzo (a) anthracene (BaA),(Chr), benzo [b] fluoranthene (BbF), benzo [k] fluoranthene (BkF), benzo (a) pyrene(BaP), indeno (1,2,3-c, d) pyrene (IP), dibenzo (a, h) anthracene (DahA), benzo (g,h,i)pyrene (BghiP), and assess their ecological risk to provide reference and basis for riskmanagement decisions.Methods：(1) According to the detection method’s appendix of drinking water standardGB5750.8, the determination of16kinds of EPA priority PAHs in water was establishedby solid phase extraction-gas chromatography/tandem mass spectrometry(SPE-GC/MS/MS).(2) From2012to2013,in the dry season, the water level period andwet period of10sampling points of Lake Chaohu, a total of30water samples werecollected to monitor for one year.(3) According to test results, the pollutioncharacteristics of PAHs were described. According to the literature, diagnostic ratios ofPAHs were used to analyze the pollution sources (4) As the use of the U.S.Environmental Protection Agency (US EPA) and PAHs ecological baseline values andaquatic toxicity data, the quotient method and risk coefficient method were used toevaluate the ecological risks.Results：(1) The determination method of16PAHs was established by SPE-GC/MS/MS. The linear correlation coefficients of PAHs in the range of1.0-1000.0ng/L were over0.999. The minimum detectable concentration of PAHs were0.2～1.0ng/L. Therecoveries ranged from84.1%to113.2%, and the relative standard deviations were2.5%~5.1%.(2)16PAHs were detected in Chaohu Lake at a low levels of control, ΣPAHsconcentration range of the dry season:234.69~1058.8ng/L, level season:157.40~514.23ng/L, wet season:108.77~560.29ng/L;and benzo(a)pyrene concentrationsrange of dry season: nd~9.00ng/L, level season: nd~0.61ng/L, wet period: nd.(3)16kinds of Chaohu Lake in water priority control PAHs detected in varying degrees, inthe whole, the major PAHs contaminants detected are the same top five as naphthalene,fluorene, phenanthrene, fluoranthene, pyrene; the percentages of PAHs in differentseasons were dry season:28.67%,7.82%,22.11%,6.01%,21.58%, level season:43.90%,10.35%,10.66%,10.63%,7.02%, wet season:30.65%,8.89%,33.33%,7.29%,6.60%.(4) In addition to benzo (a) pyrene and dibenzo (a, h) anthracene werenot detected in the wet season, the different types of water pollution of PAHs were nosignificant change, while showing a certain level of concentration distribution.ΣPAHsconcentrations:dry season (4954.89ng/L)> wet season (3008.34ng/L)> water season(2470.69ng/L).Conclusion：(1) PAHs were detected in varying degrees, Nanfei, Shiwuli, East LakeCentre, Tangxi, Zhong Temple and East Lake Centre, six sampling points benzo (a)pyrene test results in the dry season were over China’s " Surface water environmentquality standard "(GB3838-2002) in the limit of2.8ng/L, which East Lake Centre testresults exceeded " Drinking water health standard"(GB5749-2006) in the limit of10ng/L. Benzo (a) pyrene test results in level and wet water period were in line with thestandard requirements. Each sampling point total PAHs results did not exceed "Drinkingwater health standards"(GB5749-2006) in the reference limits of2μg/L.(2) In general,the main sources of pollution in order to burn: The pollution in level and wet waterperiod came mainly from the combustion of petroleum products as well as grass, wood, coal, while the the pollution in dry season came mainly from emissions and oilpollution chemical products or disclosure.(3) The hazard quotient method was used toevaluate ecological risks of different water period, overall, the quotient ranged from0to6.4310-1, the average value is0to3.4110-1All the quotient is less than1, exceptfor benzo (a) pyrene quotient>10-1in the dry season, the rest of the compoundsquotient values were <0.05, with less risk.(4) Risk factor evaluation method was usedto evaluate ecological risks of PAHs, each corresponding risk quotient of water: dryseason5.1310-4~1.8310-3, level season1.8610-4~1.2510-3, wet season3.5410-4~1.5910-3, which were much smaller than a smaller risk.