Mercury content in hairs of mother-child pairs in Slovakia as a biomarker of environmental exposure

The mercury content in hairs was determined in the framework of the European funded projects COPHES and DEMOCOPHES to test the feasibility of an EU-HBM (Human Biomonitoring) approach generating comparable data. The aim of the Slovak participation in DEMOCOPHES was to obtain and contribute the Slovak data to the harmonization of Human Biomonitoring. Pre-analytical and analytical phase for mercury in hair measurements and activities developed for the harmonization analysis within COPHES/ DEMOCOPHES projects were conducted under a strict quality assurance program (QA/QC). Total mercury in hair was determined by thermal decomposition-gold amalgamation atomic absorption spectroscopy (AMA- 254 Advanced Mercury Analyzer.) Two interlaboratory comparison investigations (ICIs) and two external quality assessment schemes (EQUAS) were conducted before the beginning of the COPHES/DEMOCOPHES projects. The laboratory successfully completed both ICIs and EQUAS schemes and was allowed to analyze all DEMOCOPHES samples of the Slovak Republic. In summary, 129 mother-child pairs were recruited to pilot study of DEMOCOPHES in Slovakia from two different locations representing urban and rural environment. The analyzed data from Slovakia showed relationship between frequency of fish meals consumption (especially sea fish and sea food products) and mercury concentrations in hair of mothers and children. The exposure levels for a sampled population in Slovakia (children 0.092 (0.080-0.106) [μg.g^-1], mother 0.130 (0.113-0.148) [μg.g^-1]) are below the EU level (children 0.145 (0.139-0.151) [μg.g^-1], mother 0.225 (0.216-0.234) [μg.g^-1]) up to an order of magnitude lower than the limit medically important (FAO/WHO health-based guidance value of 2.3 μg.g^-1 JECFA - Joint FAO/WHO Expert Committee on Food Additives).