摘要
采用GC-ECD检测、GC/MS-MS确证的方法分析成都市14个区县蔬菜地土壤中有机氯农药（OCPs）残留水平、分布特征及可能存在的生态风险.结果表明：不同样点间OCPs残留量差异较大（20.18-104.33μg.kg^-1）,近郊区县远低于边缘区县;被检出的18种OCPs中,DDTs与HCHs检出率最高（100%）,残留水平为16.11-99.51μg.kg^-1与1.31-9.34μg.kg^-1,分别占OCPs残留总量的87.68%和8.15%,六氯苯次之（90%）,灭蚁灵、环氧七氯、硫丹Ⅰ和γ-氯丹也有不同程度的检出（44.29%-47.14%）,多分布于近郊区县,艾氏剂、狄氏剂、异狄氏剂、毒杀芬的检出率较低（32.86%-37.14%）,多分布于彭州、都江堰、大邑、崇州等地;土壤中OCPs的各种异构体、代谢物变化规律显示,DDTs、HCHs残留主要源于早期的使用或大气输入,但不排除金堂、青白江、新津等地研究期内可能有DDTs输入,崇州、彭州、都江堰、大邑等地可能有HCHs输入;生态风险分析显示,HCHs残留对于土壤生物的风险较低,而DDTs则可能对鸟类和土壤生物具有一定生态风险.
To determine current levels of organochlorine pesticides（OCPs） and to assess their distribution characteristics and potential eco-risk in vegetable soil,soil samples were collected from fourteen districts and counties in Chengdu region of Sichuan province and twenty-three kinds of OCPs were quantified by means of gas chromatography equipped with a 63Ni electron-capture detector（GC-ECD） system.The results show that OCPs were found widely in all these samples and ranged from 20.18 to 104.33 μg·kg^-1,and residue levels of OCPs in vegetable soils from the outskirts of Chengdu（e.g.Shuangliu county,Long quanyi District,Pi county,Xindu District and Wenjiang District） were apparently less than those from outlying counties.Among eighteen kinds of OCPs found in the soil samples,including dichlorodiphenyltrichloroethane（DDT） and its principal metabolites dichlorodiphenyldichloroethylene（DDE） and dichlorodiphenyldichloroethane（DDD）,hexachlorocyclohexane（HCH） and its isomers（α-,β-,γ-,and δ-HCH）,aldrin,hexachlorobenzene,dieldrin,endrin,a-endosulfan,γ-chlordane,heptachlor epoxide,toxaphene and mirex,DDTs and HCHs were detected in all soil samples,with a range of 16.11～99.51 μg·kg^-1 for DDTs and 1.31～9.34 μg·kg^-1 for HCHs,and were the main components in residues of OCPs,accounting for 87.68% and 8.15% of the total,respectively.Hexachlorobenzene has an occurrence of 90%,a-endosulfan,γ-chlordane,heptachlor epoxide and mirex were detectable in a range of 44.29%～47.14% of all the samples,which were mostly collected in the outskirts of Chengdu.However,aldrin,dieldrin,endrin and toxaphene were only found in these sites in northwestern of Chengdu,such as Pengzhou,Du jiangyan,Dayi and Chongzhou）,accounting for 32.86%～37.14% of the collected soil samples.Various isomers in OCPs and the changing rule of metabolins indicate residues of DDTs、HCHs in the soils might come from the old usage or atmosphere input,but there might be input into environment recently in Jintang,Qin bai-jiang and Xinjin regions for DDTs,and so does in Pengzhou,Du jiang-yan,Dayi and Chongzhou regions for HCHs.The eco-risk analysis shows that HCHs residues in the soils have no obvious influence on the geobiont there,while DDTs might have certain ecological risks on birds and geobiont.
出处
《成都大学学报（自然科学版）》
2011年第3期195-200,共6页
Journal of Chengdu University（Natural Science Edition）
基金
国家自然科学基金(40971149)
成都大学校科技基金(2011XJZ12
2011XJZ26)资助项目
关键词
蔬菜地土壤
有机氯农药
生态风险
成都市区
vegetable soil
organochlorine pesticides
eco-risk evaluation
Chengdu region
