激光诱导击穿光谱法测定玩具油漆表面铅含量

采用家用铅检测试剂对编号为2579e的表面含铅油漆标样进行了定性测量,讨论了铅在玩具油漆表层中的深度分布,并建立了激光诱导击穿光谱法测定玩具油漆表面铅含量的方法。为减弱自吸收的影响,在铅405.78 nm谱线处,采用谱线强度(I)与铅浓度(c)关系的对数形式建立校准曲线。实验表明,线性方程为lgI=5.56+0.44·lgc,曲线的拟合度(R)为0.956,方法检出限为72 μg/g。采用方法对碳酸盐岩石成分分析标准物质GBW07136进行测定,结果与认定值的相对误差为8.3%,10次平行测定的相对标准偏差为7.1%。采用方法测得市购橘色玩具小车表面铅的含量是18.5 mg/g。

Determination of lead in paint surface of toy by laser induced breakdown spectroscopy

Qualitative determination of lead-containing surface paint reference material numbered as 2579e was conducted with home lead testing reagent,and the depth distribution of lead in the paint surface of toy was discussed. Based on this,a method for the determination of lead content in paint surface of toy was established by laser-induced breakdown spectroscopy. In order to reduce the impact of self-absorption,the calibration curve was obtained in the logarithmical form of spectral intensity I and the element concentration c at lead 405.78 nm. The results indicated that the linear equation was lgI=5.56+0.44·lgc, with fitting degree R of 0.956,and the detection limit was 72 μg/g. This method was used to the determination of carbonate rock composition analysis certified reference materials GBW07136. The relative error between the found and the certified value was 8.3%,and the relative standard deviation for ten times was 7.1%。The lead content of orange toy car purchased from stores was 18.5 mg/g.