Pollution anthropogenic sources

There are numerous kinds of toxicants that may cause alterations in ecosystems. These are normally regarded as pollutants from anthropogenic sources, but they may come from natural sources as well. Examples of such naturally occurring toxicants are hydrogen sulfide from geothermal sources or heavy metals, such as lead, leached from minerals. 

At the Bagnoli brownfield site, Tarzia et al. (2002) (as part of his PhD program with University of Naples Federico II) carried out a study aimed to discriminate anthropogenic pollution sources from natural pollution sources. For this study, heavy metals and Pb isotope data from soils, waste materials, scum, and slag samples from the brownfield site were used. 

Deterioration of materials in the built environment is one of the considerations with regard to the Justification for more stringent controls on anthropogenic pollution sources. There are both economic and aesthetic concerns involved reduced service life of common construction materials is primarily an economic consideration, while irreversible damage to art objects and historic buildings has a strong emotional context as well. 

Local monitoring is conducted in zones where point pollution sources or their complexes (cities and industrial centres) are significant, i.e. where the anthropogenic impact both on nature and human health is the most prominent. 

Alterations in trace metal concentrations in the marine environment due to man s activities are difficult to establish, since natural levels are often poorly known, or when known show variations. At present, measurement of concentration gradients (both vertical and horizontal) from known pollution sources is the primary method to assess trace metal contamination of the marine environment. High trace metal inputs into estuarine or coastal areas from industrial effluents as well as from river run-off have been measured. Without knowledge of the make-up of these source materials, distinguishing between a natural and an anthropogenic origin for increased metal concentrations is an insoluble problem. 

Several observations have shown that hydrogen is affected by pollution sources. The hydrogen molecule is an important product of incomplete combustion in several anthropogenic and natural processes. The production of H2 by industrial combustion and automobiles is estimated to vary from 15 Tg H2/yr (Novelli et al., 1999) to 25 Tg H2/yr (Schmidt, 1974). According to Crutzen et al. (1979) 9 to 21 Tg H2/yr are produced by forest and savanna burning, especially for agricultural purposes in tropical regions. 

The observation b) is best explained by the existence of a biogenic maritime source of VOC in the upwelling region off the coast of Africa, or by an as yet unidentified anthropogenic pollution source. The observation d) may imply that loss of ROx occurs on aerosol or via a homogeneous reaction with an as yet unidentified radical. 

In a meq basis SO4 and NO3 together have a variable contribution to total anions in precipitation Amazon - 34% Santos - 47% Cubatao - 69% Sao Paulo - 87% Vila Parisi - 93%. In the Amazon with no plausible pollution source, chloride is the principal anion, whereas in the other locations with high anthropogenic contribution, SO4 and NO3 tend to be dominant. Vila Parisi is a critical case, where SO4 alone corresponds to 88% of total anions in precipitation. 

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