Anthropogenic chemical

Very many substances are suspected of being EDs. These include both naturally occurring and anthropogenic chemicals and some of the most important are listed in Table 2. The main sources of human exposure to EDs are as follows. 

There is now very clear evidence that a wide range of anthropogenic chemicals can be considered as potential endocrine disrupters in fish (Table 1), but it is rather less clear whether they cause actual endocrine disruption in intact animals... 

Ferrario JB, Deleon IR, Tracy RE. 1985b. Evidence for toxic anthropogenic chemicals in human thrombogenic coronary plaques. Arch Environ Contain Toxicol 14 529-234. 

Polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans and ortho-unsubstituted polychlorinated biphenyls (non-ortho polychlorobiphenyls) are three structurally and toxicologically related families of anthropogenic chemical compounds that have in recent years been shown to have the potential to cause serious environmental contamination due to their extreme toxicity [77-82], These substances are trace-level components or byproducts in several large-volume and widely used synthetic chemicals, principally polychlorobiphenyls and... 

These types of models, while incomplete, are steps toward the formulation of composite models, which depend on future availability of compositional data. Moreover, these structural models are an important aid in understanding the interactions between anthropogenic chemicals and terrestrial organic matter. However, due to the heterogeneity of humic substances in the environment, provision of an exact, general structure does not seem feasible. 

Whether such disposal is intentional or incidental, significant quantities of pesticides and pesticide wastes end up in natural and artificial aquatic systems. Thus, any consideration of the disposal of this broad category of anthropogenic chemicals must include an understanding of the reaction mechanisms and principal pathways for degradation of pesticides in aquatic systems. Of the degradative pathways relevant to such systems, hydrolysis reactions are perhaps the most important type of chemical decomposition process ( 1 7 ). 

The anthropogenic chemicals were by far the most numerous group of compounds and are the compounds of greatest concern to this study. In reviewing concentration and source data for these chemicals, it becomes apparent that they are of three types Those found in industrialized urban areas with no specific production source those commonly used in manufacturing processes with multiple sources and those specific to a single industrial site and traceable to that source. 

Since the middle of the nineteenth century we have introduced increasing quantities of complex, man-made (anthropogenic) chemical compounds into the natural enviromnent. Many of these substances are recycled by microbial action, whilst others are poorly... 

Many anthropogenic chemicals end up in incinerators or wastewater treatment facilities. We need to be concerned about the reaction by products formed in such treatment facilities. 

Figure 2.22 Examples of important anthropogenic chemicals exhibiting a phosphorus-containing functional group. Some of the common uses of the chemicals are given in parentheses.

With three-quarters of the earth s surface covered by water and much of the remainder covered by soil, it is not surprising that water and soil serve as the ultimate sinks for most anthropogenic chemicals. Until recently the primary concern with water pollution was that of health effects due to pathogens, and in fact this is still the case in most developing countries. In the United States and other developed countries, however, treatment methods have largely eliminated bacterial disease organisms from the water supply, and attention has been turned to chemical contaminants. 

Growth in industrial, agricultural and many other activities caused by increasing human population has resulted in a rapid increase in inputs of anthropogenic chemicals into the environment, including the chemicals that are generally referred to as persistent toxic substances (PTS). 

Olah GA, Prakash GKS, Goeppert A (2011) Anthropogenic chemical carbon cycle for a sustainable future. J Am Chem Soc 133(33) 12881—12898... 

Anthropogenic chemicals may first enter the environment by aquaculture, agriculture, illegal and legal manufacturing processes, human use and disposal, septic or municipal sewage, and animal husbandry. Once in the environment, their fate depends upon the type and physicochemical properties of the media and of the substance itself. 

Accurate and precise identifications and measurements of specific chemical substances are fundamental to environmental studies and protection programs. Determinations are required to understand natural background concentrations of chemicals in the environment, the nature and extent of environmental pollution by anthropogenic chemicals, trends in concentrations of these substances, the transport and fate of chemical substances, and the causes of variations of concentrations intime and space. Accurate and precise determinations are also required to assess human health and ecological risks caused by exposure to natural and anthropogenic substances, establish air and water quality standards, develop pollution control strategies, evaluate the effectiveness of pollution prevention and treatment technologies, and monitor compliance with and the effectiveness... 

Fig. 5.3 Natural and anthropogenic chemicals identified in water samples.

Macalady, D. L., Tratnyek, P. G., and Grundl, T. J. (1986) Abiotic Reactions of Anthropogenic Chemicals in Anaerobic Systems A Critical Review, J. Contam. Hydrol. 1, 1-28. 

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