Dr. Tume-Zapata, Pedro

Urban areas are constantly growing. By 2050, the urban world population, it is predicted to reach 6 billion. Being component of cities environment, urban soils have elevated levels of potentially toxic elements from anthropogenic action. The aims of this study are (1) to establish background levels of potentially toxic element in soils in the city of Coronel and (2) to assess the pollution and identify its origin. Samples (129 in total) were collected in Coronel, from 43 sites in schoolyards. Three samples were taken at each site: 0–10 cm, 10–20 cm and 150 cm depth. Principal component analysis (PCA), cluster analysis (CA) and depth ratios were applied to distinguish the origin of the contamination. The geoaccumulation index, contamination factor and the integrated pollution index were used to estimate the pollution. The median concentration of the chemical elements in 0–10 cm depth was Ba 38 mg kg-1; Co 15 mg kg-1; Cr 18 mg kg-1; Cu 22 mg kg-1; Mn 536 mg kg-1; Ni 35.5 mg kg-1; Pb 6 mg kg-1; V 94 mg kg-1; Zn 65 mg kg-1. Principal component analysis and CA suggested that Co, Ni and Mn were mainly derived from geogenic origin, while Ba, Cr, Cu, Pb, V and Zn from anthropic origin. Contamination factor indicated that some soil samples were classified as considerable contaminated to very highly contaminated by Ba, Pb, Zn and V.

The specific objectives of this study were: (1) to establish background content levels of potentially harmful elements in topsoil of Quintero and Puchuncavi districts; (2) to assess the degree of topsoil pollution and identify the local sources of pollution; and (3) to assess the health risk of metal exposure to population. Data from a Chilean Environmental Ministry report were analyzed. Multivariate analysis suggests that the potentially harmful elements are split into two main groups, which can be explained by controlling geogenic (Ni, V and Zn) and anthropogenic (As, Cd, Cu and Pb) factors. The spatial distribution of As, Cd, Cu and Pb displays a spatial pattern around the Puchuncavi-Ventanas industrial park. The background values determined with MAD (median absolute deviation) method include As 31.6 mg kg-1, Cd 0.7 mg kg-1, Cu 296 mg kg-1, Ni 16.9 mg kg-1, Pb 48.6 mg kg-1, V 199 mg kg-1 and Zn 192 mg kg-1. The pollution indices reported considerable contamination to very high contamination in some soil samples. Hazard quotient values were higher for children than for adults, due to the ingestion and dermal absorption, while the cancer risk index values were in the acceptable range.

Attic dusts provide an indirect measure of airborne pollutants deposited in the urban environment. The objectives of this study are: (1) to determine the concentrations of As, Ba, Cd, Co, Cr, Cu, Mn, Ni, Pb, Sr, V and Zn in attic dust in the City of Coronel, (2) to evaluate the source apportionment of PHE and (3) to assess the risk of health effects from exposure in adults and children. In the City of Coronel, attic dust samples were collected in 19 houses. The concentrations of As, Ba, Cd, Co, Cr, Cu, Mn, Ni, Pb, Sr, V and Zn were measured in ICP-OES after Aqua Regia digestion of <75 µm dust sample. The median (and the range) concentration (mg kg−1) of potentially harmful elements was: As 16 (7–72), Ba 154 (53–251), Cd 0.8 (0.25–14.5), Co 12, (8–22),Cr 38 (22–482), Cu 107 (44–1641), Mn 698 (364–1245), Ni 51 (24–1734), Pb 66 (18–393), Sr 131 (52–252), V 129 (57–376) and Zn 815 (107–9761). The exploratory data analysis shows that Ni, Cu, Cr, Zn, Pb and As distribution is dominated by anthropogenic sources and characterized by high extreme values. Principal component analysis shows four factors. One factor is geogenic, while the other three factors are associated with transport emissions and the industrial park. The resulting median of cumulative noncarcinogenic risk (HIs) value for attic dust was 3.49 for children. This is significant, as any value greater than one indicates an elevated risk.

The objectives of this study are (a) to determine the background concentration of As, Cd, Cr, Hg and Pb in Arica commune; (b) to determine the degree of soil contamination in Arica city using environmental indices and (c) to evaluate the human health risk of these potentially toxic elements. In the rural area of Arica commune, 169 samples were taken and 283 samples were taken in the urban area of Arica city. Total concentrations of Cd, Pb and Cr were determined by EPA 3052 and EPA 6010 C. Mercury was determined by EPA 7473. Arsenic was determined by EPA 7061A. The available concentrations of As and Cr were determined by dilute hydrochloric acid and EPA 6010C. Environmental indices were applied for pollution and US EPA model was used to evaluate human health risk. Background concentrations were As 18.2, Cd 1.12, Cr 73.2, Hg 0.02 and Pb 11.8 mg kg−1, respectively. Environmental indices show that soil samples are located between slightly contaminated to extremely contaminated. Human health risk analysis shows that children have higher levels of risk than adults. The analysis with available concentrations of As and Cr shows no carcinogenic risk for adults and children, but 81% and 98% of the samples were between 10–6 and 10–4, that means intermediate risk.