Andrade Valéria F, Durães Alisson F S, Cassimiro Douglas L, de Pinho Gevany P, Silvério Flaviano O
a Institute of Agricultural Sciences, Federal University of Minas Gerais , Montes Claros , Brazil.
J Environ Sci Health B. 2017 Apr 3;52(4):267-273. doi: 10.1080/03601234.2016.1273003. Epub 2017 Jan 17.
The current environmental legislations recommend monitoring chemical contaminants such as polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans before the use of sewage sludge on the agricultural land. In this study, a solid-liquid extraction with low-temperature purification (SLE-LTP) was optimized and validated to determine 2,3,7,8-tetrachlorodibenzo-p-dioxin and 2,3,7,8-tetrachlorodibenzofuran in sewage sludge and soil samples. The analyses were performed by gas chromatography-mass spectrometry operating in the selective ion mode (GC-MS-SIM). Acetonitrile:ethyl acetate 6.5:1.5 (v/v) was the best extraction phase, and the recoveries percentages were close to 100%. The linearity was demonstrated in the range of 1.25-25 µg L of 1.25-20 µg L for sewage sludge and soil, respectively. Matrix effect was proved for the two compounds and in the two matrices studied. Extraction percentages were between 78 and 109% and relative standard deviations ≤ 19%. The proposed method is faster than methods described in the literature because showed a few steps. The quantification limits (LOQ) in sewage sludge were 6.4 and 32 ng TEQ kg for 2,3,7,8-TCDF and 2,3,7,8-TCDD, respectively. In soil, LOQs were 0.8 and 8.0 ng TEQ kg for 2,3,7,8-TCDF and 2,3,7,8-TCDD, respectively. These values are lower than the maximum residue limits established by European Legislation. The method was applied to 22 agricultural soil samples from different Brazilian cities and 2,3,7,8-TCDF was detected in one of these samples.
当前的环境法规建议在农业土地上使用污水污泥之前，监测多氯二苯并 - 对 - 二恶英和多氯二苯并呋喃等化学污染物。在本研究中，对低温净化的固液萃取法（SLE-LTP）进行了优化和验证，以测定污水污泥和土壤样品中的2,3,7,8 - 四氯二苯并 - 对 - 二恶英和2,3,7,8 - 四氯二苯并呋喃。分析采用在选择离子模式下运行的气相色谱 - 质谱联用仪（GC-MS-SIM）进行。乙腈：乙酸乙酯6.5:1.5（v/v）是最佳萃取相，回收率接近100%。污水污泥和土壤中两种化合物的线性范围分别为1.25 - 25 μg/L和1.25 - 20 μg/L。在所研究的两种基质中，均证明了这两种化合物存在基质效应。萃取率在78%至109%之间，相对标准偏差≤19%。所提出的方法比文献中描述的方法更快，因为步骤较少。污水污泥中2,3,7,8 - TCDF和2,3,7,8 - TCDD的定量限（LOQ）分别为6.4和32 ng TEQ/kg。在土壤中，2,3,7,8 - TCDF和2,3,7,8 - TCDD的LOQ分别为0.8和8.0 ng TEQ/kg。这些值低于欧洲法规规定的最大残留限量。该方法应用于来自巴西不同城市的22个农业土壤样品，其中一个样品中检测到了2,3,7,8 - TCDF。
