Hair Mercury Levels in Pregnant Women: Fish Consumption as a Determinant of Exposure.

The consumption of fish in food may contain mercury, a harmful element and dangerous chemical detrimental to human health. The purpose of this study was to determine the mercury level in the hair of pregnant women with different fish intakes in their diets. The concentration of total mercury in hair was determined using an atomic absorption spectrometer. In this study, 98 pregnant women were invited to participate (aged from 18 to 48 years). The mean content of mercury in the hair of pregnant women in Northwestern Russia was 0.428 mg/kg (ranging from 0.018 to 3.1 mg/kg). As a result, 22% of women had mercury values above 0.58 mg/kg, which is considered dangerous for the fetus. The hair mercury concentration in a village area was higher than that in a city area (i.e., 0.548 mg/kg and 0.326 mg/kg). Moreover, the maximum level of mercury was noted for a group of pregnant women who consumed more than 5 kg/month of fish and fish products. Furthermore, the consumption of freshwater fish in the diet leads to a higher mercury content in the hair of pregnant women than the consumption of marine fish.

Effects of lipid extraction on stable isotope ratios of carbon and nitrogen in muscles of freshwater fish.

The extraction of lipids by the Folch method from the muscles of all the fish studied led to statistically significant differences in the values of δ15N. At the same time, lipid extraction led to a statistically significant increase in δ13C in pike and roach, and to a statistically insignificant decrease in δ13C in perch and bream. Thus, lipid extraction cannot serve as a universal method of sample preparation for the analysis of the isotopic composition of carbon (13C/12C) and nitrogen (15N/14N) in fish muscles. The differences between the δ13C values in the samples before and after lipid extraction were statistically investigated by different models. It is shown that mathematical correction method models can be used, but the results are depending on the fish types.

Assessment of the consumptive safety of mercury in fish from the surface waters of the Vologda region in northwestern Russia.

It is known that the consumption of fish is the main source of mercury intake in human beings. In this study, the concentration of mercury in the muscle tissue of fish from different reservoirs of northwestern Russia was found to be 0.01-1.68 µg/g wet weight. The features of mercury accumulation in the muscle tissue of fish, depending on their type, trophic specialization, body weight, length, and the type of water body, were also revealed. Of the fish studied, 7% had mercury concentrations above the regulatory levels of the Russian Federation. The proportion of examined fish, the consumption of which will lead to an excess of the permissible weekly intake of mercury in the individual, is 44% for preschool children (2-5 years old), 34% for children of primary school age (6-10 years old), and 17% for adults. Special attention is drawn to the fact that the mercury content in fish that does not exceed the sanitary and hygienic standards (normative levels) of the Russian Federation may still be unsafe for the health of the population, especially children.

High variability of mercury content in the hair of Russia Northwest population: the role of the environment and social factors.

PURPOSE: The purpose of this work is to study mercury levels in the hair of different social and demographic groups of the population of the Vologda region in Northwest Russia. This region is selected due to a heterogeneous distribution of rivers and lakes-a resource base for fishing. METHODS: The mercury content was determined in the hair from the root with a length of about 2 cm. The concentration of total mercury in human hair was determined by the atomic absorption method without preliminary sample preparation using an RA-915M mercury analyzer and a PYRO-915 + pyrolysis unit. RESULTS: The average level of mercury in the human hair was 0.445 µg/g (median 0.220 µg/g). The concentration of mercury in the hair of people older than 44 years (0.875 µg/g) was three times higher than in the hair of children under 18 years of age (0.270 µg/g). People who eat fish less than once per month had a hair mercury concentration of 0.172 µg/g, for 1-2 times a month 0.409 µg/g, once a week 0.555 µg/g, and several times a week 0.995 µg/g. The concentration of mercury in the hair of smokers (0.514 µg/g) was higher than in the hair of non-smokers (0.426 µg/g). CONCLUSION: Significantly higher concentrations of mercury were observed in the hair of participants from the western part of the region, where reservoirs are the main commercial sources of fish products. The data showed that the main source of people's mercury intake was fish.