Environmental concerns motor vehicle emissions

The buyers of motor vehicles have been substantially positive concerning the need to have cleaner running vehicles. Although the required emission control devices and other mandated safety equipment have increased the cost of new motor vehicles, sales have not been significantly effected. The current environmental awareness and concern are evidence of the general population s new found knowledge and acceptance of both mobile and stationary source emission controls. 

A number of combustion and chemical production processes contribute to environmental concentrations of PCDD/F. Sources that have traditionally caused the greatest concern include municipal waste incinerators, hospital waste incinerators, bleached chemical wood pulp and paper mills, motor vehicles and wood combustion. We have attempted to represent the most recent data available on PCDD/F emissions from these sources. It should be remembered that the list presented here is by no means exhaustive. Potential sources of TCDD not discussed in the following paragraphs include discharges from metal processing and treatment plants, copper smelting plants and pentachlorophenol production. 

Over the same period, emissions of nitrogen oxides (NOx) were predicted to remain at current levels or to increase, depending specially on the growth of motor vehicle transport. Such predictions were not initially viewed with any sense of environmental concern because of the accepted nutrient properties of deposited nitrogen and its possible fertilizing action on the terrestrial environment. However, as... 

The Control of Industrial Pollution Water Quality and Health Aspects of the Chemistry and Analysis of Substances of Concern in the Water Cycle The Role of Wastewater Treatment Processes in the Removal of Toxic Pollutants Sewage and Sewage Sludge Treatment The Chemistry of Metal Pollutants in Water Effects of Pollutants on the Aquatic Environment Important Air Pollutants and Their Chemical Analysis Pollutant Pathways and Modelling of Air Pollution Legislation and the Control of Air Pollution Catalyst Systems for Emission Control from Motor Vehicles Evaluating Pollution Effects on Plant Productivity A Cautionary Tale Epidemics of Non-infectious Disease Systems Methods in the Evaluation of Environmental Pollution Problems Organometallic Compounds in the Environment. 

A second concern was that under some conditions sulfur dioxide in exhaust could be emitted as sulfuric acid as a result of catalytic oxidation over the noble metal catalyst. To answer this concern General Motors conducted a 350-car test designed to simulate sulfate emissions on a busy expressway. The U.S. Environmental Protection Agency, other vehicle manufacturers, and several independent environmental monitoring organizations participated in the experiment. This experiment showed conclusively that ambient levels of sulfuric acid under this worse-case simulated exposure situation were far below threshold levels known to produce adverse health effects. 

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