Dynamics and quantification of dissolved heavy metals in the Mahanadi river estuarine system, India

Abstract

Dynamics of heavy metals such as Fe, Mn, Zn, Cr, Cu, Co, Ni, Pb, and Cd in surface water of Mahanadi River estuarine systems were studied taking 31 different stations and three different seasons. This study demonstrates that the elemental concentrations are extremely variable and most of them are higher than the World river average. Among the heavy metals, iron is present at highest concentration while cadmium is at the least. The spatial pattern of heavy metals suggests that their anthropogenic sources are possibly from two major fertilizer plants and municipal sewage from three major towns as well as agricultural runoff. The temporal variations for metals like Fe, Cu, and Pb exhibit higher values during the monsoon season, which are related to agricultural runoff. Concentrations of Ni, Pb, and Cd exceed the maximum permissible limits of surface water quality in some polluted stations and pose health risks. Dissolved heavy metals like Fe, Mn, Cr, Ni, and Pb exhibit a non-conservative behavior during estuarine mixing, while Zn, Cu, and Co distribution is conservative. Distribution of cadmium in the estuarine region indicates some mobilization which may be due to desorption. The enrichment ratio data suggest that various industrial wastes and municipal wastes contribute most of the dissolved metals in the Mahanadi River. The Mahanadi River transports 18.216 × 10(3) t of total heavy metals into the Bay of Bengal and the calculated rate of erosion in the basin is 128.645 kg km(-2) year(-1).

Assessment of the characteristic of nutrients, total metals, and fecal coliform in Sibu Laut River, Sarawak, Malaysia

“…The main natural sources of metals into the aquatic system are the weathering of soils and rocks and precipitation; or from anthropogenic activities such as industrial, domestic, and urban sewage runoffs (Rippey 1982;Caccia and Millero 2003;Du Laing et al 2008;Nduka and Orisakwe 2009;Sundaray et al 2012). Elevated concentrations of total Zn were observed at station 9.…”

“…Besides nutrients, excessive amounts of heavy metals have been introduced to estuarine and coastal environments as a result of intense industrial development and anthropogenic activities (Fianko et al 2007;Nduka and Orisakwe 2009;Sundaray et al 2012;Zhang et al 2012;Lacerda et al 2013). Heavy metals are deemed to be dangerous pollutants and have raised environmental concern due to their toxicity, persistence and non-degradability, bioaccumulation in organisms, and ultimately their effect on human health (Burgos and Rainbow 2001;Kress et al 2004;Otero et al 2005;Kurun et al 2007;Du Laing et al 2008).…”

Lead distribution in coastal and estuarine sediments around India

“…Considerable data for Pb concentrations in sediments are available in the literature from the estuarine regions of Ganges/Hooghly and Mahanadi estuaries (Subramanian, 1993;Subramanian et al, 1988;Sarkar et al, 2004;Chatterjee et al, 2007;Banerjee et al, 2012;Mukherjee and Kumar, 2012;Saha et al, 2001;Ramesh et al, 1999;Sundaray et al, 2012;Raj et al, 2013). However, data from the coastal areas of this region are scarce.…”

Pollution Status of River Hindon From Ghaziabad to Noida With Special Reference to Heavy Metals

“…The main anthropogenic sources are disposal of untreated and partially treated industrial effluents and sewage containing toxic metals, as well as metal chelates from different industries and indiscriminate use of heavy metalcontaining fertilizers and pesticides in agricultural fields [1], [42]. Several researchers have studied heavy metal contamination in various Indian rivers with respect to industrial, municipal, and domestic pollution [49], [05] [48], [39], [16], [17], [18], [36], [33].Various aspects related to water quality of different Rivers in India and its tributaries have been studied by various researchers [26], [27], [46], [09], [10], [11], [12], [13], [14], [29], [41], [44], [16], [35]. …”