Impaired lung functioning in humans, as well as other respiratory problems, has been shown to result from exposure to elevated concentrations of ozone. Children and asthmatics are particularly sensitive in this respect. Damage to sensitive plants, including agricultural crops and forest trees, is occurring at current ambient concentrations. Moreover, ozone contributes to the degradation of various materials, and especially of organic ones, such as paints. When forest soil becomes acidified, essential nutrients are leached out, reducing its fertility.
Acidification also causes the release of potentially harmful metals.
Widespread damage to plant and animal life in tens of thousands of lakes and rivers is another serious consequence of acidification. Eutrophication Extensive biological effects on terrestrial as well as aquatic ecosystems can be traced to an excess of nitrogen, which greatly change and impoverish the systems by reducing the diversity of their plant species. This is also a problem in marine environments, causing algal blooms and oxygen depletion. A key pollutant, contributing to all the above effects, is nitrogen in oxide forms. But others also affect the environment.