Non-occupational exposure to trace elements in Finland – Urinary and blood biomonitoring study

The aim of this study was to assess the exposure to trace elements of the non-occupationally exposed, non-smoking, working-age population in Finland, and to provide reference values for these trace elements in the urine and blood. Urine samples were analysed for 30 trace elements and blood samples for eight elements. The samplings took place in 2020.

In the urine samples (n = 147), most of the studied trace elements were quantifiable; only the indium and iridium results were below the limit of quantification. In the blood samples (n = 143), all the trace elements were quantifiable. The results regarding four trace elements in the urine and five trace elements in the blood were statistically different among the females to those among the males. In most cases, exposure was higher among the females than the males. An age-dependent trend was only observed in the results regarding lead in blood and copper in urine. In comparison to data from other countries, the blood lead levels were lower in Finland, but urinary arsenic and selenium levels were generally higher.

The results of this study will be used to set reference values for use in occupational health. We emphasize that it is important to use an appropriate reference population to identify occupational exposure to trace elements when setting reference values. Especially when considering a reduction in occupational exposure limit values and the corresponding health-based biological limit values for trace elements, it is essential to understand that the background population exposure varies to correctly interpret the data from occupationally exposed populations.