Erythrocytes Constitute the Main Blood Compartment for Aluminum

Abstract

Aluminum (Al), a trace metal with no biological function and toxic to humans and animals, is associated with hematological/metabolic alterations and neurodegenerative processes such as Alzheimer's disease (AD). Further evidence supports Al's role in the etiology of AD and validates use of readily accessible tissues such as peripheral blood. Basal Al concentration has been reported in plasma and serum, while studies in erythrocytes are scant. Here, we report optimal conditions for simultaneous determination of Al concentration in blood compartments from humans and sheep. Al was determined by electrothermal atomic absorption spectrophotometry in whole blood, plasma, serum and red blood cells (RBCs). Solvent type and composition, matrix modifier concentration and sample age were tested on the reproducibility of Al determination. Significant interindividual variability was observed in human blood samples in the different components possibly due to the inclusion of healthy donors and patients with AD in a single group. RBCs had larger variability in Al concentration and values were affected by the solvent used. The Al concentration in RBCs, plasma and serum was 70%, 30% and 25% of the total blood, indicating that RBCs constitute the major compartment for Al. Simultaneous determination of Al in all blood components under optimal conditions may help to clarify this biological toxin's role in degenerative diseases.