Biomarkers of low-level mercury exposure through fish consumption in pregnant and lactating Slovenian women.

In order to assess the mercury exposure of pregnant and lactating women in Slovenia, levels of total mercury (THg) and methylmercury (MeHg) were determined in hair, cord blood and breast milk. In addition, the frequency of fish consumption was estimated, because fish is generally the main pathway for human exposure to MeHg. Hair samples were collected from 574 women participating in this study, while cord blood and breast milk samples were collected from 446 and 284 women, respectively. As expected, the levels of THg in hair (median (Med)=297 ng/g, 10th percentile (P10)=73 ng/g, 90th percentile (P90)=781 ng/g), cord blood (Med=1.5 ng/g, P10=0.5 ng/g, P90=4.2 ng/g) and breast milk (Med=0.2 ng/g, P10=0.06 ng/g, P90=0.6 ng/g) were low, due to low consumption of fish (X=25 g/day). A significant linear correlation was found between levels of lnTHg in hair and lnTHg in cord blood (r=0.87, 95% confidence interval (CI): 0.84-0.89), between levels of lnTHg in hair and lnMeHg in cord blood (r=0.94, 95% CI: 0.90-0.96) and between lnTHg levels in cord blood and lnTHg levels in breast milk (r=0.36, 95% CI: 0.25-0.47). Spearman's rank correlations between the frequency of fish consumption and THg in hair (rs=0.35, 95% CI: 0.28-0.42), and between the frequency of fish consumption and THg in cord blood (rs=0.43, 95% CI: 0.36-0.51) or MeHg in cord blood (rs=0.31, 95% CI: 0.06-0.52) were weak. This could be due to the approximate information on fish consumption obtained from the questionnaires, the high variability of MeHg concentrations in fish and a relatively high proportion of inorganic mercury in the biomarkers which originates from sources other than fish. In conclusion, THg levels in cord blood, THg levels in hair and MeHg levels in cord blood are suitable biomarkers of low-level Hg exposure through fish consumption. Compared to cord blood, hair samples are easy to collect, store and analyse.

Relevance of meat fat content and fruit and vegetable intake for the oxidative status of pigs.

BACKGROUND: The aim of the present study was to evaluate the effect of substituting lean meat with fat meat on oxidative stress in a diet with or without fruit and vegetables. METHODS: Thirty-two pigs were divided into groups and fed isocaloric daily rations: LM+FV (balanced diet with lean meat and fruit and vegetables); FM+FV (as LM+FV, but lean meat was substituted with fat meat); LM-FV (as LM+FV, but without fruit and vegetables), and FM-FV (as FM+FV, but without fruit and vegetables). Oxidative stress was evaluated by measuring the 24-hour urine malondialdehyde excretion rate, the degree of leukocyte nuclear DNA damage, the concentration of tocopherols in blood plasma, erythrocyte glutathione peroxidase activity and the total antioxidant status of plasma. RESULTS: The substitution of lean meat with fat meat modestly increased the rate of leukocyte DNA damage only in the diet with fruit and vegetables but had no effect in the group deprived of fruit and vegetables. Regardless of the fruit and vegetable content of the diet, the substitution of lean meat with fat meat did not affect any other parameters measured. In comparison to both fruit- and vegetable-containing diets, the deprivation of fruits and vegetables in the LM-FV and FM-FV groups significantly increased the rate of leukocyte DNA damage and reduced the plasma alpha-tocopherol level (significant only for FM+FV). CONCLUSION: The substitution of fat meat with lean meat in a diet with or without fruit and vegetables has only a marginal or no effect on oxidative stress. But fruit and vegetable exclusion markedly increased the level of oxidative stress.