Controlling transboundary air pollution requires the cooperation of nation states to control domestic air pollution emissions and their effects, including long-range transport of air pollutants affecting other countries. Active international cooperation is necessary to develop appropriate national policies and by means of exchange of information, consultation, research and monitoring to coordinate national action for combating air pollution including long-range transboundary air pollution.
The Geneva Convention on Long-range Transboundary Air Pollution defines "long-range transboundary air pollution" to mean, air pollution whose physical origin is situated wholly or in part within the area under the national jurisdiction of one State and which has adverse effects in the area under the jurisdiction of another State at such a distance that it is not generally possible to distinguish the contribution of individual emission sources or groups of sources.
Transboundary air pollution is of particular concern in relation to forest damage, soil and freshwater acidification, corrosion of materials and other effects of acid deposition and sulphur emissions. Persistent organic pollutants are also a general concern.
Current mechanisms of pollution control/regulation were tailored to past characteristics of pollution sources. Large industrial plants have long been responsible for the major share of pollution. Control and the enforcement of standards were adequate measures, as the number of such sources was limited. Economic instruments were also used, but on a limited scale. This is particularly true in the countries in transition, where current economic instruments were developed in the 1970-1980s to finance environmental investment funds. In the context of centrally planned economies and prices, economic instruments could not provide a market incentive to improve the environment, so no experience was gained in that area. Today, the current level of taxes/charges is far from reflecting the full environment and health costs. They also tend to be too low to provide significant incentives for mitigation.
Most countries are faced with a growing burden of non-point and small pollution sources, for which control and standard enforcement are inadequate owing to the large number of actors involved (users of fertilizers and pesticides, users of motor vehicles, and small-scale industry, for instance). Economic instruments are more suitable for managing this type of pollution.
Rapidly industrializing countries can control environmental degradation if they apply effective environmental regulations, provided they are consistent, reasonable, and enforced effectively and even- handedly. Most firms can reduce emissions substantially at modest cost. Even in OECD countries, where regulations are strict, pollution control costs rarely exceed two percent of the value of sales. Problems are encountered in industrializing countries because standards are vague; monitoring is inadequate; and enforcement is lax, discriminatory, or sometimes non-existent.
This strategy features in the framework of Agenda 21 as formulated at UNCED (Rio de Janeiro, 1992), now coordinated by the United Nations Commission on Sustainable Development and implemented through national and local authorities.
Paragraph 24 of the 1998 UN/ECE Declaration reaffirms European commitments to reduce national emission levels of lead, cadmium and mercury from a combination of industrial sources, transport, combustion processes and waste disposal and incineration.
The Convention on Long-range Transboundary Air Pollution was signed in Geneva in 1979 and entered into force in 1983. It has been ratified by 33 governments (1993) and the European Community. This Convention is the first internationally legally binding instrument to deal with problems of air pollution on a broad multilateral basis. It constitutes the framework within which the Contracting parties identify problems posed by transboundary air pollution and elaborate protocols on specific pollutants.