The main aim of this study was to assess the level of mercury accumulation in the hair of students studying in the Vologda Region, Russia. Particular attention is devoted to clarifying the relationship between the metal concentration in the hair and the amount of fish in the diet. It was found that the mercury content in the hair of Vologda Region residents aged 17–21 is in the range from less than 0.002 mg/kg to 1.69 mg/kg, the median of the indicator for the entire sample is 0.14 mg/kg. The median value of mercury content in the hair of males (0.12 mg/kg) is lower than in the hair of females (0.16 mg/kg). The lowest metal concentrations were observed in individuals living in the city of Cherepovets and the highest metal concentration among the entire sample and in females in the western areas, and males in the eastern areas of the Vologda Region. The concentration of metal in the hair of the urban population is lower than in subjects living in rural areas. A higher metal content in the hair was recorded in individuals whose diet usually contains fish twice a month.

The content of total mercury in the hair of adolescent residents of the industrial center of North-West Russia varied from less than 0.002 to 0.83 mg/kg. The content of total mercury in the hair of males is 1.5-2 times lower than that of females. The relationship between the body mass index of females and the content of total mercury in the hair (for the entire observation period rs=0.28–0.48, at p < 0.05) was observed. It was found that the concentration of metal in the hair of the study participants depended on the frequency of fish consumption. Over a three-year observation period, an increase in the indicator values of the concentration of total mercury in the hair was recorded among 70% of the study participants, on average by 0.03 mg/kg per year. Indicators of the content of total mercury in the hair of females and males in the city of Cherepovets did not exceed the standard values established in Russia and in the world. At the same time, the recorded values of the annual increase in the content of total mercury in the hair, allow us to predict the potentially hazardous levels of metal in the body of the study participants when they reach adulthood.