Pollutants physical properties

There are literally many thousands of chemical compounds that are potential air pollutants. It would be impossible to present all the pertinent data and information needed to evaluate each and every air pollution scenario. There are, however, a wealth of information and data bases that are available on the worldwide Web, along with a number of standard hard copy references to obtain information on the chemical and physical properties, and health risks of potential atmospheric contaminants. 

SELECTED CHEMICAL AND PHYSICAL PROPERTIES OF POTENTIAL ATMOSPHERIC POLLUTANTS... 

Table 1 is a compilation of chemical and physical properties data for selected atmospheric contaminants. This information is useful for evaluating pollution problems. The following are abbreviations used in the table. 

Important issues in groundwater model validation are the estimation of the aquifer physical properties, the estimation of the pollutant diffusion and decay coefficient. The aquifer properties are obtained via flow model calibration (i.e., parameter estimation see Bear, 20), and by employing various mathematical techniques such as kriging. The other parameters are obtained by comparing model output (i.e., predicted concentrations) to field measurements a quite difficult task, because clear contaminant plume shapes do not always exist in real life. 

Environmental organic pollutants may be degraded depending on their toxicity, solubility, distribution constant Kow because physical properties of hydrophobic chemicals may affect the solubility and therefore the amount of organic carbon available in the aqueous phase for microbial assimilation and further metabolism (Schwarzenbach and Westall 1981). Chemicals are subject to volatilization and such loss is not assessed in most of the study except for physical transformation and material balance purposes. Polyaromatic hydrocarbons (PAHs) are known to volatilized during incubation even with capping and more then 40% of the initial chemicals could be found lost (Yin and Gu, unpublished data). When proper control was not included and such... 

Heikkila et al. (1996) have expanded the work of Hurme and Jarvelainen (1995) with environmental and safety aspects (Fig. 11). The alternatives are simulated to determine the material and heat balances and to estimate the physical properties. Then the alternatives are assessed in economic terms for which the internal rate of return is used. The environmental effects are estimated by equivalent amount of pollutant that takes into consideration the harmfullness of the different effluent substances. With environmental risks are also considered aspects of occupational health to choose inherently healthier process. Even though most health related rules are considered later in the work instructions, health effects should also be a part of the decision procedure. The inherent safety is estimated in terms of the inherent safety index as described later. 

The assessment of rate and distribution of environmental pollutants in various phases including air, water, and soil is important for the risk assessment of chemicals [48]. The partitioning of chemicals among different phases is usually assessed using a critical list of physical properties including vapor pressure (VP), aqueous solubility, ainwater partition coefficient, and octanol-water partition coefficient. 

Another model, used in the USA, is the OASYS Pollution Prevention Optional Analysis System, developed by the Toxic Use Reduction Institute. Technologies are assessed on a variety of hazard criteria, including acute and chronic human toxicity, physical properties, aquatic impacts, persistence/bioaccumulation, atmospheric releases, disposal, chemical properties, energy/resource use, product hazard and exposure potential. Alternatives are rated to... 

TABLE 7-1 Physical Properties of Pollutant Gases and Their Site of Action or Absorption in the Respiratory Tract ... 

Table 8.3 Effect of volatilization on physical properties of residual kerosene. Reprinted from Galin Ts, Gerstl Z, Yaron B (1990) Soil pollution by petroleum products. Ill Kerosene stability in soil columns as affected by volatilization. J Cont Hydrology 5 375-385. Copyright 1990 with permission of Elsevier...

Although the release of large numbers of these highly chemically enriched particles may have profound health and environmental consequences, the published literature contains virtually no data characterizing the distribution, physical properties, chemical composition, and source terms of a broad range of important primary pollutants emitted in submicrometer particles. 

PERSONAL MONITORING IS A RELATIVELY NEW CONCEPT in community air pollution measurement research (1-3). This fact is not surprising because most air pollution investigations have been directed toward the characterization of the ambient atmosphere, the observation of pollutant trends, the acquisition of data on chemical kinetic parameters and on the physical properties of aerosols, and the determination of compliance to national and other standards (4). Before the late 1970s, research on personal monitors was primarily conducted in industrial settings (5, 6) because American Confer-... 

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