Persistent organic compounds sources

The elaborated conceptual model is a schematic image of studied phenomenon in the form of interconnected information blocks sources of persistent organic compounds,... 

Persistent organic pollutants (POP) and heavy metals were in the focus of interest until the begiiming of the 1990s and intensive monitoring programs and ecotoxico-logical studies had been conducted. As a result, due to adoption of appropriate measures and elimination of the dominant pollution sources a drastic reduction of emission of these nonpolar hazardous compounds have been achieved and today these compounds are less relevant for the industrialized countries. 

This section of this paper reports on a detailed study of the organic compounds in the Delaware River. Since most of our previous studies have dealt with isolated chemical plants on small rivers, we felt it would be instructive to study a complex river system surrounded by several large-scale chemical manufacturers. This would give us information on the effluents from several industrial dischargers, the relative persistence of chemical discharged from any single source, and the movement of these industrial chemicals in a major river ecosystem. 

In different compartments of the environment, sediments accumulate mainly heavy metals and persistent organic pollutants (POPs), which reach aquatic ecosystems from different sources. Metal ions do not remain dissolved in water for long they are liable to be precipitated as a result of oxygenation, the formation of different compounds (carbonates and sulfates), or sorption on mineral surfaces and the organic fraction of sediments.83... 

Abstract In the last decade, it became increasingly evident that the fuel oxygenate methyl tertiary butyl ether (MTBE) is nearly ubiquitous in the worldwide environment. The detection frequency of MTBE rivals other volatile organic compounds (VOCs) that have been produced and used for a much longer period of time. Its mere presence in water bodies used as drinking water reservoirs (rivers, lakes, or groundwater tables) has aroused concern about its potential sources, persistence, or possible adverse effects (aesthetic or toxic implications) for end-users and aquatic life. The purpose of this chapter is to provide an updated overview of the current environmental concentrations, the occurrence of the pollutant in the different aquatic compartments, the relevance of diffuse and point sources, and the different alternatives for remediation of MTBE contaminated sites. 

Source The polychlorinated biphenyls were used extensively in manufacturing electrical equipment until their potential for environmental damage was recognized. PCBs are among the most stable organic compounds known. They are poorly metabolized and lipophilic. They are therefore highly persistent in the environment and accumulate in the food chain. 

Therefore, dust and its associated fine particulate matter tend to become a sink for semi volatile organic compounds (SVOCs) (Butte and Heinzow 1994). Calculations suggest that many SVOCs have long indoor persistence, even after their primary sources have been removed. If the only removal mechanism is ventilation, moderately sorbing compounds (with octanol—air partition coefficients (K a) > 10 ) may persist indoors for hundreds to thousands of hours, while strongly sorbing compounds (Koa > 10 ) may persist for years (Weschler and Nazaroff 2008). 

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