Ozone and air pollution

Fairchild, E. J., S. D. Murphy, and H. E. Stokinger. Protection by sulfur com pounds against the air pollutants ozone and nitrogen dioxide. Science 130 861-862 1959. 

Textile dyes Air pollutants, ozone, and NO2 cause deterioration, reduced strength, and fading... 

The demand for trichloroethylene grew steadily until 1970. Since that time trichloroethylene has been a less desirable solvent because of restrictions on emissions under air pollution legislation and the passage of the Occupational Safety and Health Act. Whereas previously the principal use of trichloroethylene was for vapor degreasing, currentiy 1,1,1-trichloroethane is the most used solvent for vapor degreasing. The restrictions on production of 1,1,1-trichloroethane [71-55-6] from the 1990 Amendments to the Montreal Protocol on substances that deplete the stratospheric ozone and the U.S. 

Finlayson-Pitts BJ, IN Pitts (1997) Tropospheric air pollution ozone, airborne toxics, polycyclic aromatic hydrocarbons, and particles. Science 276 1045-1052. 

Heggestad, H. E., and H. A. Menser. Leaf spot-sensitive tobacco strain Bel W-3, a biological indicator of the air pollutant ozone. Phytopathology 52 735, 1%2. 

In recent years there has been increased interest in elucidating the biochemical and physiological responses of plants to air pollutants. Ozone has received particular scrutiny because of its importance in photochemical smog. The effects of ozone on the spectrum of physiological and biochemical systems has been analyzed in plant systems both vivo and vitro to... 

Finlayson-Pitts, B. J., and J. N. Pitts, Jr., Tropospheric Air Pollution Ozone, Airborne Toxics, Polycyclic Aromatic Hydrocarbons, and Particles, Science, 27b, 1045-1052 (1997). 

Ritter, J. A., D. H. Stedman, and T. J. Kelly, Ground-Level Measurements of Nitric Oxide, Nitrogen Dioxide and Ozone in Rural Air, in Nitrogenous Air Pollutants Chemical and Biological Implications, pp. 325-343, Ann Arbor Science Publishers, Ann Arbor, MI., (1979). 

Each of these considerations must be resolved before a personal monitor can be applied to air pollution research and characterization studies. Some advances have been made for carbon monoxide, volatile organic compounds, acid aerosols, and particulate matter (PM-10 and RSP these represent the masses of all particles collected in samplers with 50% cut sizes of 10 and 25 xm, respectively) and its components (12, 22-31). Each advance is still undergoing development, and further advances can be anticipated for these as well as for other pollutants. The next generation of monitors will probably include devices for some pollutants that incorporate the use of microsensors. Currently, microsensors are being examined for detection of nitrogen dioxide and ozone, but the range of sensors available suggests that they can be used for a number of compounds (10, 32) ... 

Ozone. 03 is the principal oxidizing component in photochemically produced air pollutants. Ozone probably causes more injury to vegetation than any other pollutant in the United States (6). Phytotoxic levels frequently occur near industrial complexes and densely populated urban areas. Exposure for two or more hours to concentrations of 10 parts per hundred million (pphm) of air may cause acute injury to several of the most sensitive species of plants. 

Rubber Air pollutants, oxidants and ozone cause damage and cracking... 

Clean Air Act (CAA 42 U.S. Code 7401 et seq.). States and state air control boards are required to implement regulations and develop state implementation plans (SIP) (137). Hazardous air pollutants (HAP), such as n-hexane, are regulated with National Emissions Standards for Hazardous Air Pollutants (NESHAP) and criteria pollutants [e.g., ozone (O3), particulate matter (PM), nitrogen oxides (NOx), sulfur oxides (SOx), carbon monoxide (CO), and lead (Pb)] are regulated with National Ambient Air Quality Standards (NAAQS). 

Ozone does occur in fairly large amounts under special conditions. For example, there is an unusually large amount of ozone in Earth s upper atmosphere. That ozone layer is important to life on Earth. It shields out harmful radiation that comes from the sun. Ozone is also sometimes found closer to Earth s surface. It is produced when gasoline is burned in cars and tmcks. It is part of the condition known as air pollution. Ozone at ground level is not helpful to life, and may cause health problems for plants, humans, and other animals. 

Notice that the ADI is not a direct expression of risk. Risk, recall, is a probability the ADI is a very low risk intake, or dose, with very low undefined. If there were some means to estimate the fraction of the population having thresholds lower than the ADI (the potentially at risk group), then a measure of the risk associated with the ADI could be obtained. No means exist to do this except for a few agents, particularly those such as the common air pollutants (ozone, carbon monoxide, sulfur and nitrogen oxides) that cause readily observable damage to human health. 

The extreme sensitivity of phthalocyanine sensors to oxidants has raised the possibility that common urban pollutants ozone and NOx are responsible for much of the conductivity of phthalocyanine devices in ambient conditions [133]. Indeed, phthalocyanine OTFTs on prolonged exposure to ambient air often exhibit an increase in device current however, their FET characteristics are also degraded so that they no longer can be switched off [34]. High humidity can reverse the process and restore FET characteristics. The high sensitivity of phthalocyanine OTFTs to pollutants may limit sensing applications and improved stability in... 

The protection of the world climate or components thereof has become the object of international agreements since the end of the seventies. The most important agreements to that extent are the Convention on Long-Range Transboundary Air Pollution, 1979 and its Protocols, as well as the Vienna Convention for the Protection of the Ozone Layer, 1985 and its Protocol (Montreal Protocol on Substances that Deplete the Ozone Layer, 1987). However, only the United Nations Framework Convention on Climate Change, 1992 (Framework Convention) together with the Kyoto Protocol represent a comprehensive approach to international protection of the climate. 

Outlandish as it may seem, a new scheme has been proposed to turn automobiles into air purifiers, devouring the pollutants ozone and carbon monoxide. BASF, an Iselin, New Jersey, company that specializes in the manufacture of catalytic converters for automotive exhaust systems, has developed a catalyst that decomposes ozone to oxygen and converts carbon monoxide to carbon dioxide. BASF proposes to paint the catalyst on automobile... 

O Classified as a volatile organic compound (VOC). VOC can react in the lower atmosphere to form ozone and other oxidants. VOC means any compound of carbon, excluding carbon monoxide, carbon dioxide, carbonic acid, metaUic carbides or carbonates, and ammonium carbonate, which participates in atmospheric photochemical reactions. Some compounds are specifically exempted firom this definition which is found in 40 C.F.R. 51.100(s). T Considered a hazardous air pollutant (HAP) and listed in Title III of the Clean Air Act Amendments of 1990. D A regulated stratospheric ozone layer depleter. 

The CAA of 1990 contains six titles and related provisions designed to encourage air pollution abatement and reduction. These provisions address several environmental pollution problems that affect us all, such as tropospheric ozone, hazardous pollution, mobile emissions, urban pollution, acid deposition, and stratospheric ozone depletion. Because the scope of this chapter is on solvents and the regulations that impact their use, only Titles I, III, V, and VI and their relevance to solvents will be discussed. 

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