[Study on proficiency test for determination of aluminum in drinking water in 2016].

OBJECTIVE

To evaluate the capacity of national laboratories for determination of aluminum in drinking water using proficiency testing program.

METHODS

The preparation method of the secondary standard materials were used as the reference for the sample preparation in this proficiency testing program. The homogeneity and stability of the samples were tested by single factor analysis of variance( ANOVA) and linear regression. The result provided by participant laboratories were analyzed by robust statistics and assessed using the Z-score.

RESULTS

590 laboratories throughout the country participated in the proficiency testing program. 533 laboratories, or 90. 3% of total participating laboratories, obtained satisfactory result. Results provided by 7 laboratories, or 1. 2% of total participating laboratories, were found to suggest doubts in their capacities. Finally, there were 50 laboratories, constituting 7. 6% of total participating laboratories, with result that were found to be outliers.

CONCLUSION

The capacity of national laboratories for determination of aluminum in drinking water has been ranked as satisfactory according to statistical analysis of the proficiency testing program result. Only a small portion of the participants require further improvement in their capacities.