Contaminants anthropogenic

Figure 1. Conceptual model illustrating examples of major anthropogenic contaminant sources and contaminants, their distribution within the abiotic environmental media, their movement into biota with potential food chain contamination, and potential effects at the organismal, population, conmiunity and ecosystem level of organization.

In addition, there is interest in the halogenation of a wide range of anthropogenic contaminants, some of which may occur in raw water before treatment. 

Currently available CRMs Calibrants are available for TBT (very evident, as TBT is an anthropogenic contaminant) and for a number of other organic tin compounds. There is also an interesting choice of environmental CRMs (sediment and mussel tissue) certified for TBT content. 

Smith, D.R., S. Niemeyer, J.A. Estes, and A.R. Flegal. 1990. Stable lead isotopes evidence anthropogenic contamination in Alaskan waters. Environ. Sci. Technol. 24 1517-1521. 

The polyaromatic hydrocarbons in the soil sample were quantitated by using an external standard of anthracene. The results reportedly for a polluted soil and sediment sample indicate that this flash evaporation-pyrolysis technique combined with gas chromatography-mass spectrometry is a valuable tool for rapidly screening polluted samples for virtually all types of anthropogenic contaminants except for heavy metals. 

There are other metals for which compelling cases can be made to produce contamination-free oceanic reference seawater. These include other bioactive metals (e.g., zinc, cobalt, cadmium, and copper), tracers of anthropogenic contamination (e.g., lead, Box 3.1), and non-bioactive metals used as tracers of geochemical and physical processes (e.g., aluminum). 

Gliver, B.G. Desorption of chlorinated hydrocarbons from spiked and anthropogenically contaminated sediments, Chemosphere, 14(8) 1087-1106, 1985. 

This chapter will provide an overview of regulated and emerging, unregulated DBFs, including discussion of their occurrence and formation from different disinfectants and their toxicity. Discussions will include classical DBFs formed by reactions of disinfectants with NOM and contaminant DBFs formed by reaction of disinfectants with anthropogenic contaminants. Analytical methods used in the discovery of new DBFs and for the measurement of known DBFs will also be discussed, as well as new research investigating other routes of exposure beyond ingestion. 

While generally attributed to the use of chloramines or chlorine, NDMA was recently identified in ozonated drinking water from Germany [57]. An anthropogenic contaminant containing a dimethylamine group was discovered to be the precursor in its formation (discussed in more detail in the Contaminant DBF section). 

In addition, it is important to continue research on contaminant DBFs. With increased drought and increased populations in many parts of the world, our rivers contain increasingly higher concentrations of anthropogenic contaminants, which can also form hazardous DBFs. It is important to study their formation and devise wastewater and drinking water-treatment methods that will remove them. 

Other anthropogenic contamination sources, such as disposal of unused or expired drugs or pharmaceutical industry discharges, should be assumed [26-30]. 

The zone between land surface and the water table, which forms the upper boundary of the groundwater region, is known as the vadose zone. This zone is mostly unsaturated— or more precisely, partially saturated— but it may contain a saturated fraction in the vicinity of the water table due to flucmations in water levels or capillary rise above the water table. The near-surface layer of this zone—the soil—is generally partially saturated, although it can exhibit periods of full saturation. Soil acts as a buffer that controls the flow of water among atmosphere, land, and sea and functions as a sink for anthropogenic contaminants. 

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