以题示方法测定化工企业周边土壤中的磷酸三甲酯、磷酸三乙酯、磷酸三苯酯、六溴环十二烷、十溴联苯醚和异氰尿酸酯等6种常见阻燃剂的含量。样品经除杂、粉碎、风干、过筛后,分取10.0 g与约10 g硅藻土混合,置于全自动加速溶剂萃取仪中,按照设定好的程序提取。将提取液氮吹浓缩至5 mL,过活化好的C₁₈固相萃取柱,淋洗后用10 mL体积比1∶1的丙酮-环己烷混合溶液洗脱。收集洗脱液,于60 ℃氮吹至近干,用环己烷稀释至1 mL,过0.45 μm滤膜,滤液按照优化的仪器工作条件测定。以UPLC BEH-C₁₈色谱柱为固定相,以不同体积比的乙腈和10 mmol·L^-1甲酸铵溶液的混合溶液为流动相进行梯度洗脱。各目标物用电喷雾离子源正离子模式电离,以多反应监测模式检测。结果显示:各目标物的质量浓度均在0.01~10.00 mg·L^-1内与其对应的峰面积呈线性关系,检出限(3S/N)为0.061~0.143 μg·kg^-1;对空白样品进行0.01,0.50,10.00 mg·L^-1浓度水平的加标回收试验,回收率分别为57.1%~80.2%、81.2%~90.5%、83.7%~92.8%。6次平行试验所得测定值的相对标准偏差为2.0%~4.2%。方法用于6份实际样品的分析,检出了磷酸三甲酯、磷酸三乙酯、磷酸三苯酯、六溴环十二烷和异氰尿酸酯,检出量为5.63~214.60 μg·kg^-1。

The title method was established to determine the 6 common flame retardants in the soil around chemical enterprises, including trimethyl phosphate, triethyl phosphate, triphenyl phosphate, hexabromocyclododecane, decabromodiphenyl ether and isocyanurate. After sample was removed, crushed, dried and sieved, an aliquot (10.0 g) was taken, and mixed with about 10 g of diatomite. The mixture was placed into the fully automatic accelerated solvent extractor, and extracted by the set procedure. The extract was blown to 5 mL by nitrogen, and passed through the C₁₈ solid phase extraction column activated beforehand. After rinsing, the column was eluted with 10 mL of mixed solution composed of acetone and cyclohexane at volume ratio of 1∶1. The eluent was collected, and blown to nearly dryness by nitrogen at 60 ℃. The residue was diluted to 1 mL with cyclohexane, and the solution was passed through a 0.45 μm filter membrane. The filtrate was analyzed according to the optimized working conditions of the instrument, with the UPLC BEH-C₁₈ column as the stationary phase, and the mixed solutions composed of acetonitrile and 10 mmol·L^-1 ammonium formate solution at different volume ratios as the mobile phase for gradient elution. Each target was ionized by positive ion mode of electric spray ion source, and detected by multiple reaction monitoring mode. It was shown that linearity relationships between values of the mass concentration and the peak area of each target were kept in the same range of 0.01-10.00 mg·L^-1, with detection limits (3S/N) in the range of 0.061-0.143 μg·kg^-1. The spiked recovery test was made on the blank sample at concentration levels of 0.01, 0.50, 10.00 mg·L^-1, giving recoveries in the ranges of 57.1%-80.2%, 81.2%-90.5% and 83.7%-92.8%, respectively. Six parallel tests were made, and RSDs of the determined values were found in the range of 2.0%-4.2%. The proposed method was applied to the analysis of 6 actual samples, and trimethyl phosphate, triethyl phosphate, triphenyl phosphate, hexabromocyclododecane and isocyanurate were detected, with detection amounts in the range of 5.63-214.60 μg·kg^-1.