Interaction between essential elements selenium and zinc with cadmium and mercury in samples from hypertensive...

The abnormal metabolism of metal ions plays an important role in health and disease conditions; hence, the studies about them have received much interest. The objective of this study was to evaluate the association between trace and toxic elements zinc (Zn), cadmium (Cd), selenium (Se), and mercury (Hg) in biological samples (scalp hair, blood, and urine) of hypertensive patients (n = 257), residents of Hyderabad, Pakistan. For comparison purpose, the biological samples of age-matched healthy controls were selected as referents. The concentrations of trace and toxic elements were measured by atomic absorption spectrophotometer prior to microwave-assisted acid digestion. The validity and accuracy of the methodology was checked using certified reference materials and by the conventional wet acid digestion method. The recovery of all studied elements was found in the range of 96.4-99.1 % in certified reference materials. The results of this study showed that the mean values of Cd and Hg were significantly higher in scalp hair, blood, and urine samples of hypertensive patients than in referents (P < 0.001), whilst the concentrations of Zn and Se were lower in the scalp hair and blood, but higher in the urine samples of hypertensive patients. The deficiency of Zn and Se and the high exposure of toxic metals may be synergistic with risk factors associated with hypertension.