Substances anthropogenic

MuirDCG. 1984. Phosphate esters. In The Handbook of Environmental Chemistry Anthropogenic substances, Vol. 3. Germany Springer-Verlag Berlin, 41-66. 

The research published in this book uses the presently most comprehensive multicompartment model, the first which comprises a coupled atmosphere-ocean general circulation model (GCM). GCMs are the state-of-the-art tools used in climate research. The study is on the marine and total environmental distribution and fate of two chemicals, an obsolete pesticide (DDT) and an emerging contaminant (perflu-orinated compound) and contains the first description of a whole historic cycle of an anthropogenic substance, i.e. from the introduction into the environment until its fading beyond phase-out. 

The generalized evidences on the increase of antibiotic resistance, allied with the development of analytical methods and genome exploring tools, motivated numerous studies on the environmental pollution produced by antimicrobials and other anthropogenic substances or on the diversity and distribution of antibiotic resistance genes (e.g. [3, 10, 26, 32]). Overall, these studies showed the complexity of antibiotic resistance dissemination in the environment. For instance, it was revealed that (1) not only bacterial pathogens but, very often environmental bacteria are important reservoirs of antibiotic resistance (2) antibiotic resistance may have a... 

With these five equations (Eqs. 23-42 to 23-46), two of them partial differential equations, the limits of the analytical approach and the goals of this book are clearly exceeded. However, at this point we take the occasion to look at how such equations are solved numerically. User-friendly computer programs, such as MAS AS (Modeling of Anthropogenic Substances in Aquatic Systems, Ulrich et al., 1995) or AQUASIM (Reichert, 1994), or just a general mathematical tool like MATLAB and MATHE-MATICA, can be used to solve these equations for arbitrary constant or variable parameters and boundary conditions. 

Ulrich, M. M., D. M. Imboden, and R. P. Schwarzenbach, MASAS - A user-friendly simulation tool for modeling the fate of anthropogenic substances in lakes , Environ. Software, 10, 177-198 (1995). 

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... 

However, we should keep in mind that in spite of a long history of testing we have been unable to foresee the environmental hazards of many anthropogenic substances, such as DDT, PCB, chlorinated paraffins, brominated flame retardants, PFOS and lately the pharmaceutical drug diclophenac (Oaks et al. 2004). Mankind and the environment pay a high price for these mistakes and we have to do a better job in the future. So the new challenge is When we replace one test method with a new one, it should not just be as good but better than what we have used before. 

VHOCs play an important role in atmospheric chemistry. Attention has been focused in the past especially on anthropogenic substances of this type. It seems that the importance of biogenic VHOCs in atmospheric chemistry has been underestimated, although high amounts of some of these compounds are transferred from the ocean into the atmosphere. Because of their considerable extent and their relatively high bioactivity the polar oceans substantially contribute to the global atmospheric emission of naturally produced VHOCs. 

Finally, lake sediment has been sampled for the study of UV spectra of extracts. In order to characterize the organic matter of sediments, a simple and fast two steps procedure has been designed with an ultrasonic extraction and a final UV analysis (Chabrol, 2007). After sediment drying, an ultrasonic assisted leaching step is carried out with three different solvents (1) water for soluble substances, (2) acetonitrile for anthropogenic substances and specific polar compounds, and (3) sodium hydroxide (O.lmol/L) for humic substances. Figure 2.4.13 presents the UV spectra of extracts for sediment of the studied lake. The results of the physico-chemical characterization of sample are the following Sediment very liquid (8.9% of dry matter, 33.2% of... 

The halogenated hydrocarbons are almost exclusively anthropogenic substances, produced and distributed in the environment by man. In this category there are many important products and substances for industrial and technological use but also different types of pesticides and even drugs. Furthermore, many types of very toxic halogenated hydrocarbons, unintentionally produced as contaminants in combustion and certain industrial processes, are polluting the environment. 

Field and laboratory work was begun in March of 1982. Field work was undertaken by biologists with the Louisiana Department of Environmental Quality. Analyses of biota and sediment samples for anthropogenic substances were performed at the Center for Blo-organlc Studies at the University of New Orleans. Water Quality and conventional pollutant analyses were provided by the laboratory staff of the Department of Environmental Quality. 

Jensen S, Jansson B, Olsson M. 1979. Number and identity of anthropogenic substances known to be present in Baltic seals and their possible effects on reproduction. Ann NY Acad Sci 320 436-448. 

The four chapters within the Chemistry section discuss the effects of UVR on biogeochemical cycles of various elements (Chapter 5), the photochemistry of DOM (Chapter 6), the photo-activated toxicity of several natural and anthropogenic substances (Chapter 7) and the environmental implications of photoinduced formation of reactive oxygen species (Chapter 8). Once again, the central role of DOM emerges as a unifying theme. 

The total annual input of methane from all sources to the atmosphere shown in Table 6.4 is 540 Mt, while the estimated output from atmosphere to sinks is 500 Mt. The potential inaccuracies in flux data can be seen by comparing the observed carbon isotopic signature of atmospheric methane of —47%o with that calculated from the data in Table 6.4 of c— 54%o (the latter is actually equivalent to —58%o upon correcting for the kinetic isotope effect (see Box 1.3) that operates during the hydroxyl abstraction reaction). There are clearly major gaps in our understanding of the pathways of methane into and out of the atmosphere and the fluxes involved, as there are for many anthropogenic substances (see Chapter 7). 

Chapter 4 covers studies which deal intensively with the fate of anthropogenic substances within riverine systems. In a first section (chapter 4.1.) the environmental behaviour of known contaminants, the... 

Apart from these obviously biogenic compounds only very few definite anthropogenic substances were identified. Within the group of xenobiotics 2,4 - and 4,4 -dichlorophenylmethane, DDT-derived metabolites, were most abundant. A pyrolytic conversion of related DDT metabolites to DDM cannot be excluded. Thus the occurrence of DDM in the pyrogram is only suggestive for DDT group metabolites in general. 

The occurrence of anthropogenic substances in the degradation reaction mixtures has to be discussed either by their mode of incorporation, their modification due to incorporation and their appearance in comparison to the substances obtained by traditional extraction techniques. Hence in Tab. 2 the anthropogenic compounds identified in the extracts are summarized as previously published (Schwarzbauer et al. 2001, Ricking et al. 2003). 

Fishbein L. 1984. Aromatic amines. In The handbook of environmental chemistry Anthropogenic substances. Berlin, Germany Springer-Verlag, 3 1-40. 

Vincenti M (1997) Application of mass spectrometric techniques to the detection of natural and anthropogenic substances in the sea. In Gianguzza A, Pelizzetti E, Sammartano S (eds) Marine chemistry. Kluwer Academic Publishers, Netherlands, p 189 MacCarthy P, DeLuca SJ, Voorhees KJ, Malcolm RL, Thurman EM (1985) Geochim Cosmochim Acta 49 2091 Saiz-Jiminez C (1994) Environ Sci Tech 28 1773... 

The Pearl River, which is the largest river in southern China, flows across the PRDR and supphes a great deal of natural and anthropogenic substances to the South China Sea annually. The northern South China Sea (NSCS) records various substantial anthropogenic influences from the PRD economic region. 

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