海南淡水养殖环境中有机氯农药及重金属残留情况分析

Residues and assessment of organochlorine pesticides(OCPs) and heavy metals in the freshwater fish ponds of Hainan

利用气相色谱(GC-ECD)、ICP-MS和原子荧光法,对海南五市淡水区表层水体和沉积物样品中14种有机氯农药和9种重金属进行检测和评价.结果表明,水样和表层沉积物有机氯农药含量分别为5.02—60.75 ng·L^(-1)和2.30—22.67 ng·g^(-1),其中水样中含量较高的化合物有β-HCH(6.67 ng·L^(-1))、p,p'-DDT(4.01 ng·L^(-1))、o,p'-DDT(3.35 ng·L^(-1))和p,p'-DDE(3.05 ng·L^(-1)),表层沉积物含量较高的化合物为异狄氏剂(3.09 ng·g^(-1))、β-硫丹(2.40 ng·g^(-1))、p,p'-DDD(1.82 ng·g^(-1))、β-HCH(1.63 ng·g^(-1))、α-硫丹(1.59 ng·g^(-1))和p,p'-DDE(1.04 ng·g^(-1)).海南养殖水体中HCHs和DDTs污染程度与其他水域比较属中低水平.重金属检测水样中Cr、Fe、Ni、Cu、Zn、As、Cd、Hg和Pb含量分别为nd—26.58、346.7—5310、0.28—14.81、nd—9.46、3.02—15.05、132.96—186.6、nd—0.11、0.01—0.11、1.15—21.60μg·L^(-1),底泥中Cr、Fe、Ni、Cu、Zn、As、Cd、Hg和Pb含量分别为4.04—71.28、6530—37040、1.06—29.34、nd—19.26、nd—111.04、1.04—5.68、nd—0.22、0.01—0.15、3.17—61.38 mg·kg^(-1),养殖鱼塘底泥中重金属潜在生态风险综合指数(RI)为10.37—51.80,平均为25.45,综合污染指数评价该区域除个别样点外重金属污染程度较低,7种重金属的单项潜在生态风险指数生态风险均值排列顺序为:Hg>Cd>As>Pb>Cu>Zn>Cr.

The contents of heavy metals and organochlorine pesticides（OCPs） of samples in water and surface sediments collected from 9 freshwater fish pond of five cities, such as Haikou,Wenchang,Qionghai,Baotin and Lingshui of Hainan,were measured by using GC-ECD,ICP-MS and atomic fluorescence spectrometry. The residual characteristics, sources and their potential ecological risks of heavy metals and OCPs were also analyzed. The results showed that theconcentration rang of OCPs in water samples were 5. 02—60. 75 ng·L^-1,the higher content single compounds of OCPs were β-HCH,p,p＇-DDT,o,p＇-DDT,p,p＇-DDE,with the average value of6.67 ng·L^-1,4.01 ng·L^-1,3. 35 ng·L^-1,3. 05 ng·L^-1,respectively,β-HCH（6. 67 ng·L^-1）,p,p＇-DDT（4.01 ng·L^-1）,o,p＇-DDT（3.35 ng·L^-1） 和 p,p＇-DDE（3.05 ng·L^-1）,In the sediments,the rang of OCPs were 2.30—22.67 ng·g^-1and the higher content single compounds of OCPs were endrin,beta-Endosulfan,p,p＇-DDD,β-HCH,α-Endosulfan and p,p＇-DDE,with the average value of 3.09,2.40,1. 82,1. 63 ng·g^-11. 59,1. 04 ng·g^-1respectively. Compared with the waters from different areas,the level of HCHs and DDTs in the studied area were arranged from low to middle levels. In the heavy metals detected,the results showed that the range of contents of Cr、Fe、Ni、Cu、Zn、As、Cd、Hg and Pb in water samples were nd—26.58,346.7—5310,0.28—14.81,nd—9.46,3.02—15.05,132.96—186.6,nd—0.11,0.01—0.11 and 1.15—21.60 μg·L^-1,respectively,and in sediments were 4. 04—71. 28,6530—37040,1. 06—29. 34,nd—19. 26,nd—111. 04,1. 04—5.68,nd—0. 22,0. 01—0. 15 and 3. 17—61. 38 mg·kg^-1,respectively. The Integrated potential ecological risk level in sediments ranged from 10.37 to 51.80,and the single potential ecological risk followed the order： Hg As Cd Pb Cu Zn Cr. In general,the pollution extent and potential ecological risk of heavy metal in freshwater fish ponds of Hainan were not subject to heavy metal pollution and Evaluation for low risk.