Pollutants in air

Environmental Analysis One of the most important environmental applications of gas chromatography is for the analysis of numerous organic pollutants in air, water, and wastewater. The analysis of volatile organics in drinking water, for example, is accomplished by a purge and trap, followed by their separation on a capillary column with a nonpolar stationary phase. A flame ionization, electron capture, or... 

Bagg, J. (1971). The Formation and Control of Oxides of Nitrogen in Air Pollution. In "Air Pollution Control," Part One (W. Strauss, ed.). Wiley, New York. 

Vo-Dinh, T. In Identification and Analysis of Organic Pollutants in Air Keith, L. J., Ed. Butterworth Publishers Boston, 1984 Chap. 16. 

Li HR, Yu LP, Sheng GY, Fu JM, Peng PA (2007) Severe PCDD/F and PBDD/F pollution in air around an electronic waste dismantling area in China. Environ Sci Technol 41 (16) 5641-5646. doi 10.1021/es0702925... 

Meanwhile, these chemicals—like chemical agents encountered at work or in hobbies or as pollutants in air, water, soil, or food—can also cause harm. Sometimes the known mechanisms of action permit us to predict the nature of toxicity to be expected. A meta-analysis of prospective studies from U.S. hospitals indicates that 6.7% of in-patients have serious adverse drug reactions 0.3% have fatal reactions (Lazarou et al., 1998). In fact, estimates of 40,000 to 100,000 deaths per year attributed to errors in medical care, primarily due to adverse reactions to pharmaceuticals, make this phenomenon a major cause of death in the United States (Meyer, 2000). A tremendous... 

Mazurek M, Simoneit BRT (1983) In Keith LH (ed) Identification, analysis of organic pollutants in air. Ann Arbor Science/Butterworth Publishers, Woburn, MA, p 353... 

Vecera Z, Janak J. 1987. Continuous aerodispersive enrichment unit for trace determination of pollutants in air. Anal Chem 59 (11) 1494-1498. 

Melcher, R. G. Langner, R. R. Kagel, R. 0. Criteria for the Evaluation of Methods for the Collection of Organic Pollutants in Air Using Solid Sorbents,... 

Patnaik, P. Handbook of Environmental Analysis. Chemical Pollutants in Air, Water, Soil, and Soil Wastes, Lewis Publishers, New Yoik, NY, 1997 Patnaik, P.. Dean s Analytical Chemistry Handbook, 2nd Edition. The McGraw-Hill Companies, Inc., New York, NY. 2004. 

Junge, C.E. (1977) Basic considerations about trace constituents in the atmosphere as related to the fate of global pollutants, in Fate of Pollutants in Air and Water Environments, Part I (ed. I.H. Suffett), John Wiley Sons, Inc., New York, USA, pp. 7-26. 

Volatile organic compounds (VOCs) and carbon dioxide (C02) are two major indicators of indoor air pollution in air-conditioned office buildings. Indoor air quality assessments would include VOCs and C02 measurements and attempt to identify their sources so that strategies for effective control may be implemented. Options for control may be source control and ventilation. Source control is the more effective while ventilation is potentially expensive, given the unpredictable (and usually rising) cost of energy. 

Gerald van Belle holds joint appointments as professor in the Departments of Biostatistics and of Environmental and Occupational Health Sciences at the University of Washington. Dr. van Belle received his PhD in mathematical statistics from the University of Toronto. His research has focused on the use of statistics to study various environmental health issues, including exposure to pollutants in air and drinking water, and environmental risk factors for Alzheimer s disease. Dr. van Belle served as a member of the National Research Council Board on Environmental Studies and Toxicology and was a member of the Committee to Review EPA s Research Grants Program. 

Chemical Pollutants in Air, Water, Soil, and Solid Wastes... 

Handbook of environmental analysis chemical pollutants in air, water, soil, and soild wastes / Pradyot Patnaik. 

The concentration of pollutants in air is generally expressed as mg/m3 air. This unit is used to express the concentrations for all kinds of analytes including organic compounds, metal ions, inorganic anions, and particulate matter. Another unit is parts per million (ppm), which is often used to express concentrations of a specific compound. Conversion of ppm to mg/m3 is as follows ... 

There are 14 analytical methods developed by U.S. EPA for measuring common organic pollutants in air. These analytes include aldehydes and ketones, chlorinated pesticides, polynuclear aromatic hydrocarbons, and many volatile organic compounds. These methods may also be applied to analyze other similar substances. All these methods are numbered from TO-1 to TO-14 and based on GC, GC/MS, and HPLC analytical techniques. Method numbers, sampling and analytical techniques, and the types of pollutants are outlined in Table 1, while individual substances are listed in Table 2. 

Table 2 Individual Organic Pollutants in Air U.S. EPA Methods (Continued)... 

For the gas analytical measurements performed by the air quality monitoring networks, UBA provides the primary standards. In most cases these are low-concentration mixtures of pollutants in air prepared by static or dynamic blending. A completely different approach is used for ozone measurement where so-called standard reference photometers (SRP) operating in the UV spectral range are applied as primary references in several countries. These SRPs, and also that operated by UBA, are linked within an international ozone reference network which is coordinated by the BIPM. 

Mazurek, M. A., and Simoneit, B.R.T. (1984) Characterization of biogenic and petroleum-derived organic matter in aerosols over remote, rural and urban areas. In Identification and Analysis of Organic Pollutants in Air (Keith, L.H., ed.), pp. 353-370, Ann Arbor Science/Butterworth, Boston, MA. 

Here, is the experimental mean rate of reaction per unit volume of catalyst, L is a characteristic length of the porous photocatalyst (i.e., the film thickness), t is the pore tortuosity (taken as three), D is the diffusion coefficient of the pollutant in air, Cg is the mean concentration at the external surface, and e is the catalyst grain porosity (0.5 for Degussa s P25). Such a treatment was performed by Doucet et al. (2006) while taking D of the pollutants to be approximately 10 m s. The estimated Weisz modulus ranged between 10 and 10, depending on the type of pollutant, that is, some three to five orders of magnitude smaller than the value of unity, which is often taken as a criterion for internal mass transport limitation. 

The initial concentration of pollutant A The concentration of pollutant at the reactor s inlet The concentration of pollutant at the reactor s outlet The mean concentration at the external surface Concentration at the surface of the photocatalyst The diffusion coefficient of the pollutant in air True rate constant in LH expression (mol min )... 

Owing to its low cost, non-toxicity, extreme stability, wide availability, and other advantages (see discussion below), Ti02 is the semiconductor of choice for environmental applications. The main application is the mineralization of toxic organic pollutants in air, water, or soil matrices (i.e., their conversion into small, non-toxic inorganic molecules as CO2, H2O, HC1). In some cases it has been used for the reduction and removal of metal ions from aqueous solutions (e.g., Cu2+(aq) —> Cu+ — TiC>2(s)). In very few cases, both the anodic and cathodic reactions have been advantageously utilized (e.g., to remove a metal ion and to oxidize an organic molecule). 

Figure 5.2 Air concentrations (pg/m ) of a-HCH (hexachlorocyclohexane), y-HCH, endo-sulfans (sum ofendo I, endo II andendosulfan sulfate) and chlordanes (sum of trans-chlordane, cis-chlordane, and trans-nonachlor) between December 2004 and March 2005 at GAPS sites around the world. (Reproduced with permission from Environmental Science and Technology, Toward a Global Network for Persistent Organic Pollutants in Air Results from the GAPS Study, by Karia Pozo, Tom Harner et a ., 40(16), 4867-4873. Copyright (2006) American Chemical Society)...

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