Environmental effects surface water contamination

Exposure Levels in Environmental Media. Reliable monitoring data for the levels of di- -octylphthalate in contaminated media at hazardous waste sites are needed so that the information obtained on levels of di-ra-octylphthalate in the environment can be used in combination with the known body burden of di-w-octylphthalate to assess the potential risk of adverse health effects in populations living in the vicinity of hazardous waste sites. Di-u-octylphthalate has been detected in ambient air, rain, surface water, groundwater, and sediment. However, as a result of the confusion about the nomenclature for octylphthalate esters, much of the historical monitoring data available actually pertain to the branched isomer, di(2-ethylhexyl)phthalate (Vista Chemical 1992). Therefore, little current information specific to the /1-octyl isomer is available regarding concentrations of the compound in foods, drinking water, and environmental media, particularly with respect to media at hazardous waste sites. The lack of monitoring data precludes the estimation of human exposure via intake of or contact with contaminated media. 

Often, the rates of fertilization in intensively managed agriculture are intended to satiate the needs of crop plants for these chemicals, so their productivity will not be limited by nutrient availability. However, excessive rates of fertilization have important environmental costs. These include the contamination of ground water with nitrate eutrophication of surface waters caused by nutrient inputs (especially phosphate) acidification of soil because of the nitrification of ammonium to nitrate large emissions of nitrous oxide and other nitrogen gases to the atmosphere, with implications for acid rain and Earth s greenhouse effect and the need to use herbicides to control the weeds that flourish under artificially nutrient-rich conditions. 

The presence of humic and fulvic acids in surface waters and groundwaters will have a significant influence on the transport and fate of metals, radionuclides, and organic contaminants in the environment. These natural organic acids can either transport or immobilize contaminants, depending on the environmental conditions. Humic and fulvic substances can also retard or enhance the photochemical decomposition of pesticides or toxic organics. Therefore, to be sucessfiil any remediation strategies must consider the effects of humic materials. If properly understood, this behavior can be used to manipulate pollutant solubilization and facilitate containment or cleanup of contaminated sites. 

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