Contaminants riverine

Therefore the present investigation focussed on the occurrence and alteration of DDT and its metabolites within the non-extractable particulate matter (or matrix) of highly contaminated riverine sediments. It has to be noted, that this study is limited to extended analysis on only four sediment samples. Hence this report has to be characterized as a preliminary testing of the presented approach. 

Gerbersdorf, S., Jancke, T. and Westrich, B. (2005) Physico-chemical and biological sediment properties determining erosion resistance of contaminated riverine sediments temporal and vertical pattern at the Lauffen reservoir. River Neckar, Germany, Limnologica, 35, pp. 132-144. 

Relatively little contamination from PCBs was found in sediments from riverine and pothole wetlands at national wildlife refuges and waterfowl production areas (WPA) in the north central United States in 1980 to 1982. PCBs were above detection levels (20 pg/kg) in less than 4% of the sediments a similar case was recorded in fish from WPAs (Martin and Hartman 1985). Maximum total PCB concentrations in field collections of nonbiological materials were 0.000028 pg/kg in ice, 0.000125 pg/kg in snow, 12.3 pg/m3 in air, 233 pg/L in seawater, 3860 pg/L in sediment interstitial waters, and 1800 mg/kg in sediments. Concentrations were comparatively elevated in urban areas, near anthropogenic activities, and at known sites of PCB contamination (Table 24.8). 

Ecological risk of POCs contamination due to riverine inputs to the Caspian Sea... 

Diffusion of PCBs from highly contaminated surficial sediments in areas of concern may be an important net source to the Great Lakes. In fact, PCB diffusion from the porewaters of heavily contaminated coastal and riverine sediments may justify the removal of those sediments. Porewater diffusion in open lake sediments is not a major source. Diffusion of PCBs from porewater is governed by an effective diffusion or mass transfer coefficient and the... 

Only very few studies have reported the contamination by PTS in the Indian terrestrial soils and riverine and coastal sediments (e.g., Pillai, 1986 Sarkar and Sen Gupta, 1987, 1988a,b, 1991 Ramesh et al., 1991 Sarkar et al., 1997 Sethi et al., 1999 Senthilkumar et al., 2001 Pandit et al., 2002). A review on the available information on PTS in the soils and sediments of India may be an essential prelude for understanding their effects on wildlife and human through bioaccumulation and biomagnification. 

Unlike contamination patterns in water, the OCs residue levels in coastal and riverine sediments revealed less variation between locations nationwide (Table 13.1). Similar pattern has been reported by a larger study in sediments from northern and southern countries in Asia (Iwata et al., 1994). Likewise, this is due to the prevailing high temperatures in these countries including Indonesia throughout the year and hence volatile compounds such as HCHs and DDTs remain for shorter time in the water. Tanabe et al. (1991) in their field study indicated that, more than... 

The majority of runoff from land to the oceans is dominated by riverine inputs, with minimal inputs directly from groundwater runoff. However, recent work has shown that SGD into estuaries and coastal waters is more significant than previously thought and may have significant impacts on the cycling of nutrients and contaminants. 

Van Metre P. C., Wilson J. T., Callender E., and Fuller C. C. (1998) Similar rates of decrease of persistent, hydrophobic and particle-reactive contaminants in riverine systems. Environ. Sci. Technol. 32(21), 3312-3317. 

In summaiy, the scientific research on the anthropogenic pollution of groundwater and riverine systems, especially by organic substances, comprising the sources, emission pathways, distribution and fate of anthropogenic contaminants still remains as an important challenge in environmental sciences. 

Earlier environmental investigations dealing with anthropogenic organic contaminants in riverine and groundwater systems focused mainly on the so-called priority pollutants (see also Keith and Telliard 1979). These compounds are characterised by elevated geo- and bioaccumulation rates as the result of a high environmental stability and lipophilicity. These physico-chemical properties led to a widespread, frequently ubiquitous distribution in the natural compartments. Additionally, they represent also... 

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