Characterization of soil heavy metal contamination and potential health risk in metropolitan region of northern China

Abstract

Soil in metropolitan region suffers great contamination risk due to the rapid urbanization especially in developing countries. Beijing and Tianjin, together with their surrounding regions, form a mega-metropolitan region in northern China. To assess the soil environmental quality, a total of 458 surface soil samples were collected from this area. Concentrations of Cr, Cu, Pb, Zn, As, Cd, and Hg were analyzed and compared to the Chinese environmental quality standards for soil. Multivariate analysis was carried out to identify the possible sources and Geographic Information Systems techniques were applied to visualize the spatial data. It was found that the primary inputs of As were due to pedogenic sources, whereas Hg was mainly of anthropogenic source. Other elements including Cr, Cu, Pb, Zn, and Cd were from both lithogenic and anthropogenic origins. Health risk assessment based on the maximum heavy metal concentration indicated that As derived from sewage irrigation area can result in carcinogenic lifetime risk due to ingestion and/or dermal contact of soil. The potential non-carcinogenic risk for children is significant for Pb and the cumulative effect of multiple metals is of concern for children in the vicinity of mining site. The results increased our knowledge for understanding natural and anthropogenic sources as well as health risk for metals in metropolitan soil.

Contaminants in surface water and sediments near the Tynagh silver mine site, County Galway, Ireland

“…This trend was not reported by the EPAI (2003), suggesting that processes over the past decade, such as weathering, have exposed and mobilised metals. These findings were supported by other studies that report high levels of metals within abandoned mine tailings (Lim et al, 2008, Romero et al, 2010, Qiao et al, 2011and Zornoza et al, 2011 (Brogan, 2003 andEnvironmental Protection Agency, 2003). The order of abundance of anions in the Barnacullia Stream water was SO4 2 − followed by Cl − , NO3 − , F − and PO4 3 − , with a similar order of abundance for sediment anions (Fig.…”

Assessment of Heavy Metal Contents in Surface Soil in the Lhasa–Shigatse–Nam Co Area of the Tibetan Plateau, China

“…To determine contents of Cr, Cu, Pb, Zn, Ni, Mn, and As, about 0.5 g of milled soil from each sample was digested with aqua regia (HNO 3 /HCl = 1:3) and HClO 4 (Qiao et al 2011). The mineral residues were then diluted with deionized water to a final volume of 25 mL in a volumetric flask, and were stored in the fridge at 4°C before being placed in an inductively coupled plasma-optical emission spectrometer (ICP-OES, Teledyne Leeman Labs, Hudson, NH, USA).…”

Distribution and assessment of heavy metals in the surface sediment of Yellow River, China

“…Approximately 0.5 g dried surface sediment samples were digested in 5 mL aqua regia (HNO 3 :HCl = 1:3) and heated at 140°C until the samples turned grey. Then 3 mL HClO 4 was added into the cooled samples (Qiao et al, 2011). The residues were diluted with deionized water to 25 mL for determining concentrations of heavy metals.…”