Population Exposure to Heavy Metals in a Contaminated Area

Abstract

P-677 Introduction: The area under study is an area with large industrial activity. An environmental assessment of this area showed that land, waters, particulate matter and some fresh food were contaminated with arsenic, copper, chromium, cadmium and nickel. Results from an extensive epidemiological survey to determine population level of exposure to these chemical compounds in the study area are presented here. Methods: 1089 residents of the study area were selected for the study. Another 1081 residents of the main cities of the region were also selected for comparison. Individuals were aged 5 to 69 years old. This study was carried on during a full year, to control for the possible seasonality of exposures to the chemicals under study. In the first encounter with participants, individuals were administrated a questionnaire including items about socio-demographic characteristics, occupational exposures, previous diseases, use of pharmaceutical drugs, health behaviors and other. Eight days later, individuals were made to collect a urine sample. During the seven days in between both visits, individuals were asked to keep a daily record of their meals. The second visit was done in the eight day. The urine sample was collected, and a small questionnaire on outdoor activities, use of chemical products, and other items, was administered. Also, compliance with daily meal recording was revised and completed if needed. Results: No statistically significant differences in the urine concentrations of the chemical compounds under study were found between the two areas. Concentrations are reported as μg/gr creatinine. Average concentrations for the study area and the comparison area were: arsenic (2.09 vs 2.04), cadmium (0.63 vs 0.72) chromium (0.66 vs 0.80), cupper (13.67 vs 13.61), and nickel (2.44 vs 2.87). No significant differences were found either when the 95th percentile was used. Individual factors associated to a higher concentration of chemicals in urine were age, alcohol consumption, consumption of fresh fish, smoking, and other. Discussion and Conclusions: Results reported here could be due to: differences in environmental exposure between areas are small or not well captured by urine concentrations; exposures may not be homogeneously distributed in time or space in the study area; and, some individual characteristics may be not well assessed by the methodology used. According to the results, environmental exposures to selected chemicals in the study area are of a low magnitude and not different to those of other urban settings in the region.