Validity of Geolocation and Distance to Exposure Sources from Geographical Information Systems for Environmental Monitoring of Toxic Metal Exposures Based on Correlation with Biological Samples: a Systematic Review

AbstractPurpose of ReviewIn epidemiologic studies, biomarkers are the best possible choice to assess individual exposure to toxic metals since they integrate all exposure sources. However, measuring biomarkers is not always feasible, given potential budgetary and time constraints or limited availability of samples. Alternatively, approximations to individual metal exposure obtained from geographic information systems (GIS) have become popular to evaluate diverse metal-related health outcomes.Our objective was to conduct a systematic review of epidemiological studies that evaluated the validity of GIS-based geolocation and distance to pollutant sources as an approximation of individual metal exposure based on correlation with biological samples.Recent FindingsWe considered 11 toxic metals: lead (Pb), cadmium (Cd), antimony (Sb), aluminum (Al), arsenic (As), chromium (Cr), nickel (Ni), mercury (Hg), tungsten (W), uranium (U), and vanadium (V). The final review included 12 manuscripts which included seven metals (Pb, Cd, Al, As, Cr, Hg, and Ni). Many studies used geolocation of the individuals to compare exposed (industrial, urban, agricultural, or landfill sources) and unexposed areas and not so many studies used distance to a source. For all metals, except lead, there was more animal than human biosampling to conduct biological validation.SummaryWe observed a trend towards higher levels of Cd, Cr, Hg, and Pb in biosamples collected closer to exposure sources, supporting th...
Source: Current Environmental Health Reports - Category: Environmental Health Source Type: research