Ozone, lung damage

Mitochondrial swelling occurs in vitro in association with lipid peroxidation of the mitochondrial membrane. However, the biochemical concomitants of ozone-induced damage to lung mitochondria have not been extensively studied. 

The concentration of 2.4 p.p.m. of ozone was first selected for the study, because the acute studies had shown that definite lung damage occurs at concentrations greater than 2.4 p.p.m. On the other hand, no damage was apparent at concentrations less than 2.4 p.p.m. in a single exposure for periods up to 24 hours. 

Ozone-induced lung damage Male F344 rats Decreased inflammatory response combined with increased antioxidant status... 

Nitrogen dioxide 100 (0.05 ppmv) 100 (0.05 ppmv) 1 yr Lung damage, acid rain, and formation of ozone and secondary pollutants... 

Ozone 157 (0.08 ppmv) 157 (0.08 ppmv) 8 hr Eye irritant, lung damage, and respiratory problems... 

AU three are oxidizing agents. Ozone, sulfur dioxide and nitrogen dioxide cause lung damage. 

This ozone can be harmful to people, animals, vegetation and materials in different ways. It irritates the respiratory system, it can make asthma, emphysema and bronchitis worse, and it may even cause permanent lung damage. Ground-level ozone also hastens the aging of spruce needles and causes brittleness in polymer materials, such as plastics and rubber products. 

The city of Los Angeles issues a smog alert when the ozone in its atmosphere reaches 0.5 ppm. This means that in every mole of air, there is 0.5 X 10 mol of ozone. This may not seem like much, but ozone is a very toxic substance that is particularly damaging to soft tissue such as the lungs. 

A reaction of ozone provides an example of concentration effects. Ozone in the atmosphere near the Earth s surface is a serious pollutant that damages soft tissues such as the lungs. In major urban areas, smog alerts are issued whenever there are elevated concentrations of ozone in the lower atmosphere. Nitmgen oxide, another component of photochemical smog, is a colorless gas produced in a side reaction in automobile engines. One reaction that links these species is the reaction of NO and O3 to produce O2 and NO2 ... 

The most important health effects, in terms of economic damages that can be assigned monetary values, are premature mortality and increased incidence of chronic heart and lung disease. The air pollutants that have shown the strongest association with premature mortality and heart and lung disease are PM and airborne lead. PM has also been associated with hospital admissions, respiratory infections, and asthma attacks. Ozone has also been associated with mortality, hospital admissions, asthma attacks and respiratory restricted activity days (RADs), days on which a person cuts back on his or her normal activities, but does not necessarily miss work or stay in bed. S02 and NOx do not have such significant direct effects, though they do have... 

Ozone photocopiers laser printers. irritation of eyes and respiratory tract damage lung tissue. 

Whether such species as hydroperoxy radicals and singlet oxygen will. survive collisions with the surfaces of the upper breathing tract and reach the lower lungs, as ozone does, must await further experiments. Clearly, if all the ozone molecules and all the hydroperoxy radicals are eventually absorbed in the lungs, the ozone damage will dominate, unless hydroperoxy radicals are several hundred times more damaging, which seems unlikely. 

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