Pollution from ozon depletion

Deals with issues that affect the quality of our air and protection from exposure to harmful radiation. OAR de >el-ops national programs, technical policies, and regulations for controlling air pollution and radiation exposure. Areas of concern to OAR include indoor and outdoor air quality, stationaiy and mobile sources of air pollution, radon, acid rain, stratospheric ozone depletion, radiation protection, and pollution prevention. 

Certainly, photochemical air pollution is not merely a local problem. Indeed, spread of anthropogenic smog plumes away from urban centers results in regional scale oxidant problems, such as found in the NE United States and many southern States. Ozone production has also been connected with biomass burning in the tropics (79,80,81). Transport of large-scale tropospheric ozone plumes over large distances has been documented from satellite measurements of total atmospheric ozone (82,83,84), originally taken to study stratospheric ozone depletion. 

Fortunately many people are now aware of issues such as pollution from car exhaust and ozone depletion. At the same time, Canadian chemical and related industries employ about 250 000 people and generate tens of billions of dollars annually. These industries make the products that entertain, feed, clothe, and keep Canadians comfortable. When discussing atmospheric chemistry and pollution, we must consider two important influences the economy and the environment. 

Figure 11 shows an idealised nitrogen cycle. The numbers in boxes represent quantities of nitrogen in the various reservoirs, while the arrows show fluxes. It is interesting to note that substances involving relatively small fluxes and burdens can have a major impact upon people. Thus nitrogen oxides, NO, NO2, and N2O are very minor constituents relative to N2 but play major roles in photochemical air pollution (NO2), acid rain (HNO3 from NO2), and stratospheric ozone depletion (N2O). 

Catalytic hydrotreatment is widely used in the petroleum Industry to remove sulfur, nitrogen, and oxygen from crude oil fractions. However, its use to treat chlorocarbons has not been widely reported despite the widespread use of these compounds in industrial and military operations, and despite the negative environmental impact associated with most disposal options. Catalytic hydrotreatment has the potential to be a safe alternative for the treatment of chlorinated wastes and has advantages over oxidative destruction methods such as thermal incineration and catalytic oxidation. Some of these advantages include the ability to reuse the reaction products, and minimal production of harmful byproducts, such as CI2, COCI2, or fragments of parent chlorocarbons. 1,1,1- Trichloroethane was chosen for this research because it is widely used in industry as a solvent and is on the EPA Hazardous Air Pollutant list as a toxic air contaminant and ozone depleter. ... 

Progress has been made in some areas since 1970. Emissions of pollutants from point sources into air and water have decreased. Toxic releases are decreasing. Some Superfund sites have been cleaned up. Businesses would no longer think of dumping a barrel of waste solvent on the ground at the landfill site so that the barrel could be used again for the same purpose. Control of pollutants from nonpoint sources is still a problem. There is now more international cooperation and discussion of global problems, such as ozone depletion by chlorofluorocarbons and the effect of... 

Spatial scales characteristic of various atmospheric chemical phenomena are given in Table 1.1. Many of the phenomena in Table 1.1 overlap for example, there is more or less of a continuum between (1) urban and regional air pollution, (2) the aerosol haze associated with regional air pollution and aerosol-climate interactions, (3) greenhouse gas increases and stratospheric ozone depletion, and (4) tropospheric oxidative capacity and stratospheric ozone depletion. The lifetime of a species is the average time that a molecule of that species resides in the atmosphere before removal (chemical transformation to another species counts as removal). Atmospheric lifetimes vary from less than a second for... 

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