Heavy metal induced ecological risk in the city of Urumqi, NW China

Abstract

A total of 169 samples of road dust collected in the city of Urumqi, capital of the Xinjiang Uygur Autonomous Region in northwest China, were analyzed by method of inductively coupled plasma-mass spectrometry for 10 elements (i.e., Cd, Cr, Cu, Ni, Pb, Mn, Be, Co, Zn, and U). The possible sources of metals are identified with multivariate analysis such as correlation analysis, principal component analysis, and cluster analysis. Besides, enrichment factors are used to quantitatively evaluate the influences of human activities on heavy metal concentrations. Moreover, the potential ecological risk index is applied to evaluating the ecological risk of heavy metal pollutants. The results indicate that: (1) the concentrations of the heavy metals involved were much higher in urban areas than the background values, except those of Co and U. Mn, U, and Co are mainly of natural origin; Cu, Pb, Zn, and Cr are mainly of traffic sources and are partly of industrial sources; Ni and Be are mainly the results of industrial activities, such as machine shops, firepower plants, tire and rubber factories, cement factories, and textile mills and are partly of the traffic sources; (2) with high "toxic-response" factor and high concentration, Cd has more serious influences on the environment than other heavy metals. Therefore, commercial and industrial areas are usually characterized by higher potential ecological risk when compared with residential areas and new developing urban areas. The results of this study could be helpful for the management of environment in industrial areas.

Enrichment, risk assessment, and statistical apportionment of heavy metals in tannery-affected areas

“…Cadmium has no biological function and is highly toxic to living organism (Alloway 1990). Toxic response factor (T r i ) for Cd was high (30) as compared to T r i of Cr, Cu, Zn, and Pb which along with relatively low background value (0.12) is responsible for high Cd E r i (Wei et al 2010;CEPA and CGSEM 1990). Potential ecological risk factor for multimetal (RI) represents the sensitivity of various biological communities to toxic heavy metals.…”

“…Hooda et al (1997) determined heavy metals, i.e., Ni, Cu, Zn, Pb, and Cd toxicities from biosolid-amended soils and suggested that Cd, Ni, and Zn can pose greater hazard than Cu/Pb on account of their bioaccumulation efficiency. Anthropogenic inputs of cobalt in agricultural soils include industrial effluents, traffic activities, and application of sewage sludge (Wei et al 2010). Approximately, 33-44 % of Co occurs as stable organic complexes and is unavailable to aquatic or soil-dwelling organisms.…”

“…VF2 loaded for Co, Fe, and K and their sources mainly related to parent rock material. However, these metals are also used in liming processes and may contribute toward soils contamination (Wei et al 2010). VF3 showed highest loading for pH (r = 0.87), indicating pH as one of the controlling factor for Mn availability.…”

A review of heavy metal contaminations in urban soils, urban road dusts and agricultural soils from China

“…In urban soils and urban road dusts, the anthropogenic sources of heavy metals include traffic emission (vehicle exhaust particles, tire wear particles, weathered street surface particles, brake lining wear particles), industrial emission (power plants, coal combustion, metallurgical industry, auto repair shop, chemical plant, etc. ), domestic emission, weathering of building and pavement surface, atmospheric deposited and so on [9,10,[12][13][14][15][16][17][18][19][20][21][22][23][24][25][26]. However, the anthropogenic sources of heavy metals in agricultural soils include mining, smelting, waste disposal, urban effluent, vehicle exhausts, sewage sludge, pesticides, fertilizers application and so on [27][28][29][30][31].…”

Pay Attention to the Heavy Metals Research of Environment in Arid Regions of Northwest China, and Central Asia

“…According to our preliminary investigation, there have relatively high contents of heavy metals Zn, Cu, and As metalloid）of the sediments in rivers, lakes, and soils in north slope of xs and these made very serious potential threat for the environment and local people, because when the natural conditions changes such as the water amount of the rivers and lakes and the pH values of the soils, as well as the change of the precipitation and temperature of the basin, these all may made the migration and transformation of the high background heavy metals of the environment [4,5].…”