Elevated contamination

Detecting Elevated Contamination by Comparisons with Background... 

Due to the elevated contaminant mass load a contaminant balance also has to be included in the wastewater storage constraints. This is given in constraint (8.54), where the contaminant mass present in a storage vessel at a time point is the contaminant mass from the previous time point and the difference between the contaminant mass entering and exiting the vessel. Each storage vessel is assumed to be ideally mixed, hence the concentration within the vessel is uniform. 

Macroscale, i.e. the identification of potentially unknown areas of elevated contamination and assessment of the extents of the zone of contamination. 

Dark green and yellow vegetables tend to contain elevated contaminant levels along with salad vegetables (tomato, cucumber, celery, sweet peppers, lettuce). It is also important to note that vegetable oils, margarine, and olives contain elevated contaminant levels (l.e., oils tend to be... 

Area with sediment that has similar physical characteristics as the site under investigation, but without elevated contaminant concentrations. Volume 2(10). 

All of these isotopic studies were performed on systems with elevated contamination levels or high concentrations measured and mostly on simple compound mixtures. These applications avoid the two major limitations of compound-specific isotope analyses. These limitations lie in the lower sensitivity as compared to traditional GC/MS analyses and in the requirement of complete gas chromatographic separation of the contaminants. However, natural aquatic systems, especially riverine or groundwater systems, are mostly contaminated at a low or medium level and, therefore, concentrations of individual organic compounds are low. Consequently, information on the isotopic characterization of contaminants existing in these water systems is not available up to now. 

In no case were concentrations of biocides in dust normally distributed. For those biocides present in more than 10 % of the samples the question whether there was any significant difference between the concentration used for application as a wood preservative and that used for application as an agent against insects or fleas was investigated (Walker et al., 1998). These findings were used to calculate reference values for the base contamination with certain biocides in household dust (Walker et al., 1998). Reference values are a tool in detecting an elevated contamination as an indicator of indoor pollution. 

One of efficient methods for recultivation of polluted soil is phytoremediation engaging plant-microbial associations resistant to elevated contamination levels. 

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