Sulfuric acid smog pollutant

The earliest reports of acute environmental incidents were of air pollution emergencies. In the Meuse Valley of Belgium during 1930, 63 persons died and thousands became ill from sulfur dioxide and sulfuric acid air pollution (French 1989). The Donora, Pennsylvania, smog disaster in 1948 left 20 dead and more than 5,000 ill (French 1989). 

Materials and Structures. Building materials have become soiled and blackened by smoke, and damage by chemical attack from acid gases in the air has led to the deterioration of many marble statues in western Europe. Metals are also affected by air pollution for example, S02 causes many metals to corrode at a faster rate. Ozone is known to oxidize rubber products, and one of the effects of Los Angeles smog is cracking of rubber tires. Fabrics, leather, and paper are also affected by S02 and sulfuric acid, causing them to crack, become brittle, and tear more easily. 

The first death occurred on the third day and on the fourth day, the number of deaths increased so that a temporary morgue had to be set up. The town s eight physicians were too few in number to attend to all who were affected. All during this period, the plants continued to spew pollution, containing particulates, sulfur dioxide/sulfuric acid, zinc, lead and cadmium, into the air. It was not until the morning of the 30th that the Donora Zinc Works shut down and later that afternoon, rains finally arrived and washed the smog from the air. 

Sulfur oxides, in the form of sulfur dioxide (SO-) sulfur trioxide (SO-), sulfuric acid (H-SO ) and sulfates (SO ). Most of these pollutants are emitted to the atmosphere as sulfur dioxide, which is chemically converted by oxidation to SO- and sulfates in the air. Both particulate matter from smoke and sulfur oxides are known to be components in the smogs of London. They are mainly the result of combustion of coal. 

In and around cities, there is the extra problem of industrial releases combining with already present environment pollutants (think smog) such as carbon dioxide (CO2), sulfur dioxide (SO2), sulfuric acid (H2SO4), nitrogen oxide (NO2), and nitric acid (HNO3). 

An industrial atmosphere is characterized by pollution composed mainly of sulfur compoimds such as sulfur dioxide (SO ), a precursor to acid rain, and nitrogen oxides (NO ), the backbone of smog in modern dties. Sulfur dioxide from burning coal or other fossil fuels is picked up by moisture on dust particles as sulfurous add. This is oxidized by some catalytic process on the dust particles to sulfuric acid, which settles in microscopic droplets and fall as acid rain on exposed surfaces. The result is that contaminants in an industrial atmosphere, plus dew or fog, produce a highly corrosive, wet, acid film on exposed surfaces. 

Nitrogen oxides are pollutants. They cause acid rain and photochemical smog. Nitrogen oxides also catalyse the oxidation of sulfur dioxide gas, SO2, in the atmosphere during the formation of acid rain. The sulfur trioxide, SO3, gas that is produced by this oxidation reacts with rainwater, forming sulfuric acid. The reactions below show the catalytic activity of the nitrogen oxides ... 

Hazardous-waste chemicals can enter the atmosphere by evaporation from hazardous-waste sites, by wind erosion, or by direct release. Hazardous-waste chemicals usually are not evolved in large enough quantities to produce secondary air pollutants. (Secondary air pollutants are formed by chemical processes in the atmosphere. Examples are sulfuric acid formed from emissions of sulfur oxides and oxidizing photochemical smog formed under sunny conditions from nitrogen oxides and hydrocarbons.) Therefore, species from hazardous-waste sources are usually of most concern in the atmosphere as primary pollutants emitted in localized areas at a... 

Burning fossil fuels can release air pollutants such as carbon dioxide, sulfur oxides, nitrogen oxides, ozone, and particulate matter. Sulfur and nitrogen oxides contribute to acid rain ozone is a component of urban smog, and particulate matter affects respiratory health. In fact, several studies have documented a disturbing correlation between suspended particulate levels and human mortality. It is estimated that air pollution may help cause 500,000 premature deaths and millions of new respiratory illnesses each year. 

A limited amount of work has been carried out on the effect of pollutants. Sulfur dioxide decreased the amount of iodine liberated from all reagents the difference between reagents II and III was small. Nitrogen dioxide yielded 8 to 11% interference with reagent III, and about the same with II. Five tests with 500 p.p.m. of nitric acid vapor showed an average interference of 0.5 p.p.m. of ozone with reagent III. Interferences from other smog constituents have not been completely evaluated. 

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