Why Was aMulti-Pollutant Protocol Process Initiated? Let us start with a quick sketch of the European air-pollution policy developments. Acidification ofScandinavian

lakes alarmed researchers in the late 1960s.4 The possibility that this acidification was caused by long-range atmospheric transport, and hence 'import' of pollutants, led Scandinavian researchers and politicians in the early 1970s to call for aco-ordinated international response. Although most countries saw little need for such a response at the time, possibilities for strengthening the general East-West detente process provided the necessary window ofopportunity. Hence, rather reluctantly, a loose framework Convention on Long Range Transboundary Air Pollution (LRTAP) was established in 1979 under the auspices of the United Nations Economic Commission for Europe (ECE), with membership comprising most countries in Western and Eastern Europe.5 Among other things, increasing scientific evidence ofa serious problem affecting both lakes and forests made LRTAP into an important forum for regulatory development in the 1980s. In 1985 a protocol was adopted in Helsinki calling for 30 per cent reduction ofS02 emissions by 1993. This was followed by the Sofia Protocol in 1988, calling for stabilization of nitrogen oxides (NOJ emissions by 1994, based on 1987 emission levels.6 Within the EU, directives addressing the same basic problems were also being developed.7 With processes starting in 1983-4, the Large Combustion Plant Directive was adopted in 1988 and the Car Emissions Directive in 1990.8 The next step within LRTAP was the 1991 Geneva Protocol on Volatile Organic Compounds (VOCs). VOCs are agroup ofchemicals which are precursors of ground-level ozone. The protocol called for a reduction of30 per cent in VOC emissions between 1988 and 1999, based on 1988 levels--either at national levels or within specific 'tropospheric ozone management areas'. Following the adoption ofthe VOC Protocol, negotiations on afollow-up to the 1985 Sulphur Protocol were initiated and concluded by the adoption of the 1994 Sulphur Protocol. This Protocol set out individual and varying national reduction targets for the year 2000 alone for half of the countries, and additional targets for the years 2005 and 2010 for the other half-with 1980 as the base year. The Protocol sought to reduce the gap between levels of sulphur deposition and critical loads in most of Europe by

60 per cent, except for the most acid-sensitive areas. The multi-pollutant process was initially branded as 're-

negotiating the NOxProtocol'.9 Article 5in the 1988 NOx Protocol stated that regular and subsequent reviews ofthe commitments established in 1988 were to take place. 10 With regard to the 1991 VOC Protocol, the review and renegotiation requirements were more specific. Paragraph 6 under Article 2 called for a commencement of renegotiations no later than six months after the coming into force of the 1991 Protocol, explicitly calling for attention to the role ofNOx' Hence aformal basis for a more comprehensive renegotiation process was present. However, we must not forget the more substantive basis for the process. First, by the mid-1990s acidification problems were still severe. As indicated above, faithful implementation of the 1994 Sulphur Protocol would only approximately halve the gap to critical levels in the environment. Moreover, urban airquality problems were on the increase. About 70 per cent of the population ofEuropean cities with monitoring stations were being exposed to pollution levels above ED airquality guiding values. 11 Hence the need to adopt stronger regulatory measures was clearly there. In addition, and not least important, knowledge of the interplay between a variety ofsubstances and several environmental effects was improving, and hence also the intellectualcapacity to grasp this interplay was growing. Important tools were the concept of 'critical loads'12 and the RAINS (Regional Acidification Information and Simulation) model. This model had been developed from the late 1980s by the International Institute for Applied Systems Analysis (IIASA) and utilized in the negotiations leading up to the 1994 Sulphur ProtocoI.13 Hence by the mid 1990s both formal and substantive factors pointed towards the start-up of negotiations on amore comprehensive and stronger LRTAP regulatory protocol.