Comparison of arsenic levels in fingernails with urinary As species as biomarkers of arsenic exposure in residents living close to a coal-burning power plant in Prievidza District, Slovakia.

The associations between As levels in fingernails with both As concentrations in urine and environmental samples are reported. The participants (aged 20-80 years, mean 66 years) lived in the vicinity of a coal-burning power plant with high As emissions in the Prievidza District, Slovakia. Samples were taken in 1999 and 2000. The As levels in fingernails (n = 524) were measured after washing and digestion with microwave heating by hydride generation atomic absorption spectrometry. The spot urine samples (n = 436) were speciated for inorganic As (As(inorg)), monomethylarsonic (MMA) and dimethylarsinic acid (DMA) by hydride-cryogenic trap-atomic absorption spectrometry. The geometric mean As level in fingernails was 0.10 mug/g (range, <0.01-2.94 microg/g). There was a clear association between As in fingernails and the distance of the home to the power plant (P<0.001). Geometric mean As levels were: 0.17 microg/g distance < or = 5 km, 0.10 microg/g 6-10 km and 0.08 microg/g > 10 km. The association between the distance to the power plant and total urinary As (As(sum)) (n = 436, no fish consumption during the last 3 days before sample collection) was less pronounced (P = 0.018). The As levels in fingernails were positively correlated to As in soil (n = 207, r = 0.23, P<0.001) and to As in house dust (n = 209, r = 0.30, P<0.001). The associations between urinary As(sum) and As concentrations in soil (n = 159, r = 0.13, P<0.105) and in house dust (n = 162, r = 0.14, P<0.081) were quite similar. As levels in fingernails were associated with urinary As(sum) and with the different As species in urine. It is concluded that As levels in fingernails are a reliable marker of environmental As exposure, and that As concentrations in fingernails reflect the As exposure in a similar manner compared with urinary As(sum) and As species.

Association between arsenic exposure from a coal-burning power plant and urinary arsenic concentrations in Prievidza District, Slovakia.

To assess the arsenic exposure of a population living in the vicinity of a coal-burning power plant with high arsenic emission in the Prievidza District, Slovakia, 548 spot urine samples were speciated for inorganic As (Asinorg), monomethylarsonic acid (MMA), dimethylarsinic acid (DMA), and their sum (Assum). The urine samples were collected from the population of a case-control study on nonmelanoma skin cancer (NMSC). A total of 411 samples with complete As speciations and sufficient urine quality and without fish consumption were used for statistical analysis. Although current environmental As exposure and urinary As concentrations were low (median As in soil within 5 km distance to the power plant, 41 micro g/g; median urinary Assum, 5.8 microg/L), there was a significant but weak association between As in soil and urinary Assum(r = 0.21, p < 0.01). We performed a multivariate regression analysis to calculate adjusted regression coefficients for environmental As exposure and other determinants of urinary As. Persons living in the vicinity of the plant had 27% higher Assum values (p < 0.01), based on elevated concentrations of the methylated species. A 32% increase of MMA occurred among subjects who consumed homegrown food (p < 0.001). NMSC cases had significantly higher levels of Assum, DMA, and Asinorg. The methylation index Asinorg/(MMA + DMA) was about 20% lower among cases (p < 0.05) and in men (p < 0.05) compared with controls and females, respectively.

Environmental arsenic exposure from a coal-burning power plant as a potential risk factor for nonmelanoma skin carcinoma: results from a case-control study in the district of Prievidza, Slovakia.

To investigate the risk of arsenic exposure from a coal-burning power plant in Slovakia on nonmelanoma skin cancer (NMSC) development, a 1996-1999 population-based case-control study was conducted with 264 cases and 286 controls. Exposure assessment was based on residential history and annual emissions (Asres1, Asres2) and on nutritional habits and arsenic content in food (Asnut1, Asnut2). Asres1 was assessed as a function of the distance of places of residence to the plant. Asres2 additionally considered workplace locations. Asnut1 was used to calculate arsenic uptake by weighting food frequencies with arsenic concentrations and annual consumption of food items. Asnut2 additionally considered consumption of local products. Age- and gender-adjusted risk estimates for NMSC in the highest exposure category (90th vs. 30th percentile) were 1.90 (95% confidence interval (CI): 1.39, 2.60) for Asres1, 1.90 (95% CI: 1.38, 2.62) for Asres2, 1.19 (95% CI: 0.64, 2.12) for Asnut1, and 1.83 (95% CI: 0.98, 3.43) for Asnut2. No interaction was found between arsenic exposure and dietary and residential data. Other plant emissions could have confounded the distance-based exposure variables. Consumption of contaminated vegetables and fruits could be confounded by the protective effects of such a diet. Nevertheless, the authors found an excess NMSC risk for environmental arsenic exposure.