Trends in the concentrations of mercury, copper, zinc and selenium in inhabitants of north-eastern Finnish Lapland in 1982-1991. A pilot study.

The heavy industry on the Murmansk region in Russia is releasing huge amounts of waste into the air, including heavy metals and sulphur compounds. To investigate the temporal trend in exposure to certain heavy metals among the inhabitants of north-eastern Finland, a pilot study was carried out involving serum and hair samples from group of 11 persons monitored in Ivalo in 1982 and 1991. A further 6 persons residing near the Russian border in Nellim and 10 adults and 2 children residing in the Sevettijärvi-Näätämö area also participated in 1991. In addition, serum and hair samples were also obtained from controls residing in the Helsinki area. Total mercury content, determined by flow injection analysis and the amalgam system, pointed to a decrease in concentrations in the hair of inhabitants of Ivalo, whereas mercury concentrations were found to be higher in those residing near the Russian border. The mercury concentrations in the hair of northern inhabitants were about 4 times greater than those in the hair of the people from southern Finland on average. No trend towards an increase or decrease was found in copper and zinc concentrations in hair and serum as determined by atomic absorption spectrometry in employing the flame technique. Selenium has been thought to act as an antagonist to the heavy metal mercury. The addition of selenium to fertilisers began in Finland in 1984, but such fertilisers have not been used widely in Lapland. Selenium concentrations, determined by flameless atomic absorption spectrometry, showed an increase with time in the inhabitants of northern Finland. Selenium concentrations were higher in the residents of Lapland than in the southern Finns, but this difference occurred after the addition of selenium to fertilisers has begun to be less common.