Carbon monoxide local pollution

The U.S. Environmental Protection Agency has established National Ambient Air Quality Standards (NAAQS) for protection of human health and welfare. These standards are defined in terms of concentration and hme span for a specific pollutant for example, the NAAQS for carbon monoxide is 9 ppmV for 8 hr, not to be exceeded more than once per year. For a state or local government to establish compliance with a National Ambient Air Quality Standard, measurements of the actual air quality must be made. To obtain these measurements, state and local governments have established stationary monitoring networks with instrumentation complying with federal specifications, as discussed in Chapter 14. The results of these measurements determine whether a given location is violating the air quality standard. 

For soybean-based biodiesel at this concentration, the estimated emission impacts for percent change in emissions of NO,, particular matter (PM), HC, and CO were +20%, -10.1%, -21.1%, and -11.0%, respectively (EPA, 2002). The use of blends of biodiesel and diesel oil are preferred in engines in order to avoid some problems related to the decrease of power and torque, and to the increase of NO, emissions (a contributing factor in the localized formation of smog and ozone) that occurs with an increase in the content of pure biodiesel in a blend. Emissions of all pollutants except NO appear to decrease when biodiesel is used. The use of biodiesel in a conventional diesel engine dramatically reduces the emissions of unbumed hydrocarbons, carbon dioxide, carbon monoxide, sulfates, polycyclic aromatic hydrocarbons, nitrated polycyclic aromatic hydrocarbons, ozone-forming hydrocarbons, and particulate matter. The net contribution of carbon dioxide from biomass combustion is small. 

At the local level, air pollution concerns a region within a 5-km radius. It is characterized by high concentrations of specific pollutants that may come from automobiles or industrial activities in that region. For example, emissions from vehicles can lead to high concentrations of carbon monoxide near traffic-jammed roads. High buildings and the terrain can also contribute to high local concentrations of pollutants. 

Carbon Synthesis of all organic molecules and ofbiogenetic carbonates. Carbon monoxide is slightly toxic to plants and very toxic to mammals ChP Is very toxic to all organisms. Carbon dioxide and CO are global pollutants from burning fossil fuels ChT is a local pollutant of rivers near mines. 

As discussed in Chapter 7, polluted air varies in composition from locale to locale and with the time of day and meteorological conditions in a given locale. Polluted urban air contains oxides of sulfur and nitrogen, carbon monoxide, ozone, uncombusted and partially combusted hydrocarbons from gasoline and diesel vehicles, and particulate matter. PM 2.5 particulates, the standard for evaluating pollution related to cardiovascular disease, are composed of combustion products, airborne soil, sulfates, nitrates, and heavy metals as listed in Table 29.4.141-45 ... 

At local and urban levels, it is essentially a question of vicinity pollution. Several air pollutants are concerned sulphur dioxide, SO2 (primary pollutant) nitrogen oxides NO (primary or secondary pollutants) particulate matter PM (primary and secondary pollutants) carbon monoxide, CO, (primary pollutant) (volatile) organic compounds, HC (or VOCs) (primary and secondary pollutants), and photochemical oxidants, O3, PAN (secondary pollutants). Organic compounds account for a wide range of hydrocarbons and are found in solid, liquid, and gas forms. 

The two scenarios were also used to study the impact on local air pollutants emitted from passenger car transport such as particulate matter (PM), nitrate oxides (NOx), volatile organic compounds (VOCs), and carbon monoxide (CO). These pollutants affect human mortality and morbidity and are responsible for damage to environmental quality. 

The lifetime of these species in the atmosphere is relatively short and if they were distributed evenly their harmful effects would be minimal. Unfortunately these man-made effluents are usually concentrated in localized areas and their dispersion is limited by both meteorological and topographical factors. Furthermore, synergistic effects mean that the pollutants interact with each other in the presence of sunlight, carbon monoxide, nitrogen oxide(s), and unburned hydrocarbons lead to photochemical smog, while when sulfur dioxide concentrations become appreciable, sulfur oxide-based smog is formed. 

---