Development and validation of a method for mercury determination in seawater for the production control of a candidate certified reference material

A simple, robust and reliable method for mercury determination in seawater matrices based on the combination of cold vapour generation and inductively coupled plasma mass spectrometry (CV-ICP-MS) and its complete in-house validation are described. The method validation covers parameters such as linearity, limit of detection (LOD), limit of quantification (LOQ), trueness, repeatability, intermediate precision, and robustness. The validation experiments have been carried out by spiking certified reference material (BCR-579), embedding a low mercury content. Correlation factors higher than 0.9992 were obtained for several calibration curves. Therefore, an excellent linear signal-mass fraction curve was achieved covering the whole working range. The repeatability of the method (RSDrep) was 0.5%, whereas the intermediate precision was 2.3%. Both of them were obtained at the target mass fraction (20 ng/kg). Moreover, the method was robust concerning the salinity of the seawater sample. The limit of quantification was 2.7 ng/kg, which corresponds to 13.5% of the target mass fraction in the future certified reference material (20 ng/kg). An uncertainty budget for the measurement of mercury in seawater at target mass fraction, applying the described method, has been established. The relative expanded (k=2) combined uncertainty is in the order of 7%. The major uncertainty contribution was related to the trueness assessment. Finally, the validated method has been used for the processing control in the production of a candidate certified reference material. Moreover, the method will be applied in the homogeneity and stability studies for the certification of a new candidate certified reference material.

SANCHEZ ROMERO Raquel;  SNELL James;  HELD Andrea;  EMONS Hendrik; 

2015-08-18

SPRINGER HEIDELBERG

JRC92006

1618-2642,   

https://publications.jrc.ec.europa.eu/repository/handle/JRC92006,   

10.1007/s00216-015-8833-9,