Do people from Taiwan have higher heavy metal levels than those from Western countries?

INTRODUCTION This study investigated whether heavy metal levels were higher in people from Taiwan as compared to those from Western countries. METHODS We measured the level of heavy metals (lead, mercury, arsenic and cadmium) in the blood of 40 apparently healthy adults. Since mercury does not respond to ethylenediaminetetraacetic acid (EDTA) infusion, only urine lead, arsenic and cadmium levels were determined by applying the body burden concept after calcium disodium EDTA infusion. These three heavy metals were extracted from daily urine samples for three consecutive days. RESULTS The mean blood lead, mercury and cadmium levels of the Taiwanese individuals (24.46 ± 9.69 µg/L, 9.64 ± 6.98 µg/L and 0.73 ± 0.27 µg/L, respectively) were greater than those of the Americans. The Taiwanese also had greater blood mercury and cadmium levels than the Germans. The first-day urine lead, arsenic and cadmium levels were 77.9%, 33.1% and 62.4%, respectively, of the total lead, arsenic and cadmium excretion during the three days. This indicates that the first-day urine lead and cadmium excretion represented most (> 60%) of the lead and cadmium excretion in those three days. CONCLUSION This study demonstrated that the Taiwanese population has higher blood mercury and cadmium levels than Western populations. To study the urine lead and cadmium body burden of patients, detection of first-day, rather than three-day, urine lead and cadmium levels can be done, as the former yields results that are fairly representative, and is more time- and cost-effective.