Human Biomonitoring Surveys in Slovenia: Biomarkers of Low-Level Exposure to Trace Elements

Abstract

In Slovenia, several cross-sectional studies following the same protocol were conducted in recent years to assess the extent of exposure of the Slovenian population to environmental contaminants including mercury (Hg), lead (Pb), cadmium (Cd) and arsenic (As). Status of essential elements (selenium, zinc, copper) was also assessed. The contaminants were measured in urine as well as in blood, and Hg also in hair, to demonstrate appropriateness of the selected biomarkers as an indicators of specific exposure. The exposure was compared between women (20-45 years), men (20-45 years) and children (6-11 years), as well as between different geographical regions including rural, urban and contaminated environments. In general, men had the highest exposure to Hg, Pb and As and children the lowest (p<0.001). In case of Cd, the highest exposure was observed for women and the lowest for children (p<0.001). Essential elements were the highest in fathers and the lowest in children (p<0.001). We demonstrated hair Hg as the best biomarker of organic Hg exposure through fish consumption. However, urinary Hg should be included in human biomonitoring surveys as well, as the best indicator of inorganic exposure through amalgam fillings and/or broken Hg containing thermometers. Cd exposure through smoking was better indicated by blood Cd than by urinary Cd, regardless of creatinine adjustment, as well was passive smoking in children. Pb in blood was related only to wine consumption in women and insignificantly to the type of water supply. As exposure was strongly associated with sea fish and shell fish consumption, stronger associations were found for urinary than for blood As. Educational level was related only with Hg exposure (positively) but not with the other contaminants. This work was supported by the EU 6th FP research project PHIME, National Human Biomonitoring programme financed by the Ministry of Health of Republic of Slovenia, the LIFE+ and the Slovenian Research Agency.