Contamination and Risk Assessment of Heavy Metals in Lake Bed Sediment of a Large Lake Scenic Area in China

Abstract

The exposure of heavy metals to lake bed sediment of scenic areas may pose risks on aquatic ecosystems and human health, however very few studies on risk assessment have been reported for scenic areas. Accordingly, this study determined concentration levels, and assessed contamination characteristics and risks, of heavy metals in lake bed sediment of National Scenic Areas Songhuahu (NSAS) in China. The concentrations of Zn, Cr, Pb, Ni, and Cu were determined in 29 bed sediment samples. Results showed that the mean values of Zn, Cr, Pb, Ni, and Cu were 92.69, 90.73, 38.29, 46.77, and 49.44 mg/kg, respectively. Pearson correlation coefficients indicated that organic matter was a major factor influencing distribution of heavy metals. The results for enrichment factors indicated that contamination rates and anthropogenic inputs of single heavy metals decreased in the order Cu > Ni > Pb > Cr > Zn; results of Nemerow integrated pollution index suggested that 72.41% of sampling sites were exposed to low to moderately integrated pollution, and 27.59% of sampling sites were exposed to strongly integrated pollution. According to results for potential ecological risk index, ecological risks of single and all the heavy metals in bed sediment from all the sampling sites were low. Human risks were assessed with hazardous quotients, and the results suggested that exposure of heavy metals to bed sediment posed no or little risk to human health, and the pathway of ingestion significantly contributed to human health risks.

Pollutants’ Release, Redistribution and Remediation of Black Smelly River Sediment Based on Re-Suspension and Deep Aeration of Sediment

“…Heavily polluted sediments in rivers have gradually become a significant factor in water pollution, especially in developing countries [ 1 ]. Since the water in urban rivers is relatively static, the concentrations of pollutants in the sediment, such as organic matter, ammonium nitrogen, phosphorus, and heavy metals are significantly higher than in the overlying water [ 2 , 3 , 4 , 5 , 6 , 7 ]. Sediment and overlying water are continuously exchanging material and energy, so that the pollutants maintain a dynamic equilibrium of adsorption and release [ 8 ].…”

Evaluation of temporary seasonal variation of heavy metals and their potential ecological risk in Nzhelele River, South Africa

“…Cevik et al [3] reported that SQGs are useful for the assessment of the health of sediment ecosystems as well as the protection of benthic organisms in freshwater ecosystems. Apart from various SQGs, some other indices have been formulated to test the contamination level and ecological risk of single and total heavy metals in sediments for example the geoaccumulation index (I geo ), enrichment factor (EF), Newrow integrated pollution index (P n ), contamination factor (CF) and ecological risk index (RI) [4][5][6][7][8][9]. Background levels of heavy metals in sediments of various countries are often required to calculate the relative toxicity of heavy metals in sediments but due to lack of such data in some countries, average heavy metals levels in sedimentary rock, continental crust, world shale, among others are often employed [1,6,10].…”

Graphical Methodology of Global Pollution Index for the Environmental Impact Assessment Using Two Environmental Components

“…2 = 400 (7 + 8.5) 2 = 1.665 (16) As one may observe, this value of 1.665 from Equation (16) is identical to the pollution index value given by Popa's method (1.665). This may be explained by the fact that Equation (15) is a mathematical reordering of the initial Equation (4) that can be obtained after explicit substitution of the average value via its components in Equation (4).…”

“…In case of the environmental component Water, the common quality indicators are: COD, BOD, suspended solids, floating solids, oily products, dissolved substances such as salts or phenols, and others. Likewise, water pollution index might be estimated using a single value by decreasing the number of parameters and representing data in a simple way [14][15][16][17]. According to some previous research papers [18][19][20][21][22], the representative quality indicators for Soil are: total organic carbon (TOC), extractible compounds, soil pH, etc.…”