An Optimized Method to Obtain Human Biomonitoring Data of Al, Bi, Ce, Cr, Ge, La, Li, Nd, Pr, Ti, Te and Y in Whole Blood.

Handling Interferences in Complex Matrices for Metals, Nutrients, and COD
Poster Presentation

Prepared by , K. Macey, D. Poddalgoda

Contact Information: innocent.jayawardene@canada.ca; 613-954-8363


ABSTRACT

International or national human biomonitoring data were not available for these inorganics (Al, Bi, Ce, Cr, Ge, La, Li, Nd, Pr, Ti, Te and Y), which were priority substances under phase III of Canada’s Chemical Management Plan. Approximately 6000 whole blood samples from the Canadian Health Measures Survey (CHMS) biobank were accessed to determine concentrations of these elements by Inductively Coupled Plasma Mass Spectrometry.

The Resultant concentrations were expected at ppt or ppb levels; therefore, analytical methods were optimized. The main challenges were: possible leaching of metals from storage and associated blood collecting device materials, non-homogeneity of blood samples, transportation of samples, complex matrix interferences and other analytical issues related to testing a large batch of samples in the absence of data for comparison. Quality assurance/quality control procedures were followed during sample handling, sample pre-treatment, spiking and in instrumental analysis throughout the project (1.5 years) to address these. Accuracy, specificity, sensitivity, recovery, reproducibility, and contamination were assessed using Certified Blood Reference Materials, control spiked blood samples, and method blanks along with each analytical batch.

Recoveries were in an acceptable range of 70-130%; the majority between 80-120%, with an inter assay CV ranging from 3-11%. Due to instrumental and possible contamination the method reporting limit (MRL)s of Al and Ti were higher than for other elements. Leach testing showed no contamination from storage or associated materials used for Bi, Ce, Cr, Ge, La, Li, Nd, Pr, Te, with the exception of Y, which had minor contamination close to the MRL from materials associated with blood withdrawal. Contaminations from these were not presented for Al and Ti as they had higher MRLs.

This optimized method with acceptable quality control data demonstrated that this method is suitable for biomonitoring of these elements in whole blood with the exception of Al and Ti.