Urinary levels of arsenic and heavy metals in children and adolescents living in the industrialised area of Ria of Huelva (SW Spain)

The Ria of Huelva (south-west Spain) is a highly polluted estuary as a consequence of long-term mining and industrial activities. Between 2003 and 2004, we conducted a biomonitoring study of exposure to arsenic and some heavy metals (cadmium, chromium, copper and nickel) in urine samples of a representative sample (n = 227) of children and adolescents residing in this area, and of a reference group of 196 children and adolescents living in other less industrialised areas of Andalusia (south Spain). We also assessed the determinants of the variability in urinary metals within the population of the Ria of Huelva. There were no significant differences in the concentration of metal compounds between the two groups with the exception of Cd levels, which were significantly higher in the reference group. Levels of the five metal ions in both groups were generally within the range of values reported by other biomonitoring studies for general children population, although mean Cd levels tended to be higher as compared to other European studies. Among the population of the Ria of Huelva, the main determinants of the interindividual variation in urinary metals were age, sex, area of residence, and frequency of intake of certain food items (mainly fish and shellfish). Overall, results suggest that living in the Ria of Huelva is not increasing current levels of exposure to certain metals among children and adolescents above those found in other urban areas of Andalusia.