Investigation of pollutant metals in road dust in a post-industrial city: Case study from Detroit, Michigan

Inhalation and/or ingestion of toxic heavy metals enriched in road dust have effects on humans. From inhalation and dust, release readily bioavailable elements sorbed to could lead health issues such as lung or skin cancer, kidney dysfunction, hypertension, dermal lesions, peripheral neuropathy, vascular disease. On 49 soil samples collected the Metro Detroit area, we analyzed a suite trace <63 ?m size-separated fractions quantify extent metal enrichment contamination status. We evaluated Enrichment Factor (EF), Pollution Index (PI), Geoaccumulation (GI), Load (PLI). The average Chromium (Cr) concentration 198 ppm is highest reported for any global city literature while ?80% samples, Barium (Ba), Cr, Lead (Pb), Zinc (Zn) concentrations exceeded USEPA limit. EF (Ba) was found be ?9 all rest other >1.5. PI values Ba, (Zn), Selenium (Se) indicate elevated levels Zn up moderate level. PLI >50% dusts were ?3, indicating many sites are ‘heavily polluted’. value higher than those some cities including Shanghai. Observed strong correlations between Cr-Zn Cadmium (Cd)-Silver (Ag) likely common source. Cluster analysis data Cd, Arsenic (As), Pb, appears distinct different proximally related clusters, Nickel (Ni) Ba potentially more property type clusters. In general, industrial commonly with over half (?6 11) differing from residential samples. Three generalized “groups” identified combination hierarchical cluster PCA analyses followed by varimax rotation: Group 1 characterized Ni, Ag, Zn, Copper (Cu); 2 As, Mercury (Hg), minor Ba; 3 Se. This first study report four metrics pollution along rigorous statistical analysis.