[Analysis on occupational health laboratories' proficiency testing program for determination of bovine blood lead and urinary cadmium].

Objective: To analyze the results obtained from the proficiency testing program for determination of bovine blood lead and urinary cadmium, so as to evaluate the proficiency of the laboratories, and improve the detection and quality control capability of occapational health laboratory. Methods: Prepared 3 levels of lead samples with bovine blood as base material, taking Technical Norm of Primary Reference Material as Operating standard, 60, 80, 180 μg/L were used as the standard concentration. All samples were made for 200 bottles. Normal urine were used to prepared 3 levels of cadmium samples with 5.0, 7.0, 10.0 μg/L as standard concentration, then 3 level of samples were made for 200 bottles respectively. Blood lead and urinary cadmium samples were sent to each laboratory in the form of sample pairs. One-way ANOVA was used to investigate the homogeneity. The results of each laboratory were statistically analyzed by robust statistical method, and the detection ability of the laboratory was evaluated by the Z ratio score method. By consulting the test reports and original records of each participating laboratory, the reasons for the unsatisfactory results were analyzed. Results: The statistical F of the uniformity of blood lead 1.42, 1.37 and 2.85, F<3.13, P were 0.294, 0.314 and 0.059, respectively in 31 labs. There is no statistical significance in the difference of blood lead (P>0.05). And urine cadmium was less than the critical value (P>0.05). In all, 31 laboratories participated in the test of blood lead, and 28 loboratories paticipated in urine cadmium verification. The statistical F of the uniformity of urinary cadmium 1.90, 1.35 and 1.19, F<3.13. The homogeneity of the samples were in accordance with the requirements of proficiency testing program. The satisfactory rate of the results for blood lead was 84% (26/31) , and the satisfactory rate of urinary cadmium was 93% (26/28) . In the test of blood lead, 21 of the 31 laboratories were controlled by the standard material method. Totally, 20 of them get an satisfactory level, the rate was 95%. Conclusion: Most of the laboratory test results were satisfactory, which showed that the detection capability for blood lead and urine cadmium was good. The main causes of unsatisfactory results were detection methods, tools of quality control ortraceability standards.目的： 了解和评价不同职业卫生检测实验室血铅、尿镉的测定能力。 方法： 以牛血为基质，参照《一级标准物质技术规范》的相关要求，制备加标浓度为60、80、180 μg/L的3个水平血铅样品，每个浓度的样品各制备200瓶。正常人尿过滤、去除沉淀后作为基质，制备加标浓度为5.0、7.0、10.0 μg/L的3个水平尿镉样品，每个浓度的样品各制备200瓶。采用方差分析法对样品均匀性进行统计分析。血铅、尿镉均以样品的形式发放至各参加实验室，采用稳健统计四分位距法统计各参加实验室的测定结果，并通过Z比分数法评价实验室检测能力。查看各参加实验室的检测报告及原始记录，分析结果不满意的原因。 结果： 31个血铅检测实验室的血铅样品检测所得的F值分别为1.42、1.37和2.85，F值均<3.13，对应的P值分别为0.294、0.314和0.059，同一水平血铅含量差异无统计学意义（P>0.05）。28个尿镉检测实验室的尿镉样品均匀性检测所得的F值分别为1.90、1.35和1.19，F值均<3.13（P>0.05），显示血铅样品中的铅、尿镉样品中的镉是均匀的。31个实验室参加血铅验证，28个实验室参加尿镉验证。血铅验证结果满意率为84%（26/31），尿镉验证结果满意率为93%（26/28）。血铅检测中31个实验室中有21个采用标准物质法进行质量控制，结果满意的为20个，满意率为95%。 结论： 多数参加血尿和尿镉检验的实验室检测结果较好，表明不同实验室的血铅、尿镉检测能力水平总体良好。实验室结果不满意的主要原因在于检测方法、质量控制措施或溯源标准的不同。.