[Studies on markers of exposure and early effect in areas with arsenic pollution: methods and results of the project SEpiAs. Epidemiological surveillance in areas with environmental pollution by natural or anthropogenic arsenic].

INTRODUCTION: Arsenic and its inorganic compounds are classified as carcinogenic to humans. Exposures to inorganic arsenic (iAs) in drinking water are associated with both carcinogenic and non-carcinogenic effects. The risk assessment of exposures to low-moderate levels of environmental arsenic (As) is a challenging objective for research and public health. The SEpiAs study, funded by the Italian Ministry of Health (CCM), was carried out in four areas with arsenic pollution prevalently of natural origin, Amiata and Viterbo areas, or of industrial origin, Taranto and Gela.
MATERIALS AND METHODS: 271 subjects (132 men) aged 20-44, were randomly sampled stratifying by area, gender and age classes. Individual data on residential history, socio-economic status, environmental and occupational exposures, lifestyle and dietary habits, were collected through interviews using questionnaire. In urine samples of recruited subjects, the concentration of inorganic arsenic (iAs) and methylated species (MMA, DMA) was measured using inductively coupled mass spectrometer (DRCICP- MS), after chromatographic separation (HPLC). Molecular biomarkers and biomarkers of DNA damage, as well as markers of cardiovascular risk were measured The distributions of iAs and iAs+MMA+DMA were described by area and gender, geometric mean (GM), percentiles and standard deviation (SD). The associations between As species and variables collected by questionnaire were evaluated by multiple regression analysis.
RESULTS: Results showed a high variability of As species within and among areas. Gela and Taranto samples showed higher iAs concentration compared to Viterbo and Amiata. Subjects with iAs>1,5 μg/L or iAs+MMA+DMA>15 μg/L (thresholds suggested by the Italian Society of Reference Values), are 137 (50,6%) and 68 (25,1%), respectively. A positive association between iAs and use of drinking water emerged in the Viterbo sample, between iAs and occupational exposure in the Gela and Taranto samples. Fish consumption was associated with higher iAs concentration in the whole sample, and particularly in men of the Gela sample. Similar results were observed for iAs+MMA+DMA. Subjects with iAs or iAs+MMA+DMA values higher than the 95th percentile were 15 (6Taranto, 5 Gela, 3Viterbo, 1 Amiata). The relationships between iAs and organic species (methylation efficiency ratios) were different between sex in the four areas. The relevance of polymorphisms AS3MT Met287Thr, GST-T1, GST-M1, OGG1 was confirmed. The analysis of carotid intima-media-thickness showed normal values, but higher among man of Viterbo, Taranto and Gela areas.
CONCLUSIONS: Results are informative of exposure to inorganic and organic As in large or at least non-negligible quotas of the samples. The SEpiAs results suggest a further deepening on routes of exposure to arsenic species, and support the recommendation to implement primary prevention measures to reduce population exposure.