福建省茶园土壤-茶叶的铅含量及铅同位素示踪

Lead Content and Isotopic Tracing for Soil-tea System of Some Tea Gardens in Fujian Province,China

运用微波消解-电感耦合等离子体质谱法（ICP-MS）分析了福建省内9个市县的茶园土壤和茶叶的铅含量及铅同位素组成,评价铅污染情况并解析铅来源。结果表明,茶园土壤和茶叶的铅含量分别为23.00±0.099～55.43±0.032 mg/kg和0.53±0.126～1.47±0.058 mg/kg,地质累积指数法表明茶园土壤基本为无污染,单项因子指数法表明茶叶均为安全等级。茶园土壤和茶叶铅同位素组成具有区域性,茶叶铅同位素组成相对于茶园土壤具有较低的206Pb/207Pb和206Pb/208Pb。结合铅含量相关性分析和铅同位素示踪分析,福建省茶叶铅主要来源于茶园土壤和大气。福建省茶叶铅同位素组成的同地相似性和异地差异性特征可为茶叶产地溯源和鉴别提供一定的科学依据和参考价值。

Lead concentrations and isotopic compositions（206 Pb/207 Pb and206 Pb/208 Pb） of soils and teas in tea gardens of 9 counties in Fujian Province were analyzed to assess the spatial variation of lead and trace the lead sources. Results show that the ranges of lead concentrations in soils and teas are 23. 00±0. 099-55. 43±0. 032 mg/kg and 0. 53±0. 126-1. 47±0. 058 mg/kg,respectively. Lead in the soils is almost at non-pollution level according to geo-accumulation index,and lead in the teas is also safe according to single factor index. Lead isotopic compositions of soils and teas are regional.206 Pb/207 Pb and206 Pb/208 Pb of teas are lower than those of soils. Lead in teas is mainly derived from soils of local tea gardens and atmosphere according to the correlation analysis of lead content and lead isotopic tracer analysis. The similarity and variety of lead isotopic composition in teas of Fujian Province can provide a scientific basis and reference value for traceability and identification of tea origin.