在黄河三角洲不同区域采集了26个土壤样品,利用GC-MS内标法测定土壤中22种有机氯农药(OCPs)含量,并对其残留特征、污染来源和生态风险进行了分析和评价.研究结果表明,土壤中共检测到19种OCPs,总的OCPs浓度范围为0.01-10.49 ng·g-1,平均浓度为1.678 ng·g-1.OCPs平均浓度顺序如下:DDTs＞HCHs＞氯丹类＞硫丹类,DDTs类农药的检出率最高,DDTs和HCHs是土壤中OCPs主要的组成成分,研究区土壤中DDTs和HCHs的残留水平低于国内其他地区土壤中含量,也低于规定的土壤阈值和土壤环境质量标准,本研究区土壤未受OCPs的污染.β-HCH和p,p'-DDE分别是HCHs和DDTs的主要组成成分.研究区土壤中OCPs主要来源于历史残留,无新的污染源输入.土壤中TOC和pH值对OCPs的残留存在影响,并且呈现弱的负相关性,不同类型土壤OCPs残留量存在差异,OCPs在树林土壤中的残留含量高于海岸带和原耕地土壤中.风险评价表明研究区土壤中HCHs农药残留量不会对生物产生风险;DDTs类农药对研究区生物存在可能性较小的生态风险,危害性总体较低.
Twenty-six surface soil samples collected from the Yellow River Delta were analysed for organochlorine pesticides (OCPs) by gas chromatography mass spectrometry (GC-MS) with internal standard correction.The distribution characteristics,sources and ecological risks of OCPs were studied and assessed.In total,19 OCPs were detected in the studied soils,with total concentrations ranging from 0.01 to 10.49 ng·g-1and an average value of 1.678 ng·g-1.For individual OCPs,DDTs are the highest followed by HCHs,Chlordanes,Endosulfans.The detection rate of DDTs was the highest,DDTs and HCHs were the main components of OCPs in soil.DDTs and HCHs in the studied soil were lower than those in other regions of China,and also below the regulated soil threshold and soil environmental quality standard.The soil in this study area was not polluted by OCPs.β-HCH and p,p'-DDE are the main components of HCHs and DDTs,respectively.Source analysis indicated that the soil OCPs mainly originated from historical deposition without new source input.A negative correlation was observed for TOC vs.OCPs and pH vs.OCPs,indicating that TOC and pH could affect the legacy OCPs levels in the soils.The legacy OCPs levels varied in different types of soils,with highest values in forestry soils followed by coastal and farmland soils.Risk assessment showed that the HCHs pose no risks to the organisms in the studied soils.The ecological risks contributed by DDTs are not significant.
参考文献
- 下载量()
- 访问量()
- 您的评分：
-
10%
-
20%
-
30%
-
40%
-
50%