International environmental law has tended to regulate specific environmental media and/or resources rather than particular activities or products. There is, however, now a significant body of rules which regulate those activities or products, and associated wastes, considered by the international community, within a region or globally, to be hazardous or dangerous and to merit specific attention. The Biosafety Protocol, regulating certain categories of genetically modified organisms produced via processes of biotechnology, is one such example considered in previous chapters. The reason for international attention to these substances and activities, and to wastes, lies in their potential for global or transboundary impacts on human health or the environment. For instance, toxic chemicals such as dioxins persist in the environment over long time frames and can be dispersed through air or water over a large area. Equally, activities such as the generation of nuclear energy warrant international regulatory involvement when poor safety practices or accidents result in widespread radioactive contamination. Such activities also generate hazardous wastes, which pose long-term problems of storage and disposal.
As will be seen, both in the case of hazardous substances and activities, and of wastes, there is not presently any single international organisation or treaty that establishes principles and rules of general application. The international community has instead adopted broad policy guidelines. Principle 6 of the 1972 Stockholm Declaration declared that the ‘discharge of toxic substances or of other substances and the release of heat, in such quantities or concentrations as to exceed the capacity of the environment to render them harmless, must be halted in order to ensure that serious or irreversible damage is not inflicted upon ecosystems’. According to Principle 14 of the Rio Declaration, ‘states should effectively co-operate to discourage or prevent the relocation and transfer to other states of any activities and substances that cause severe environmental degradation or are found to be harmful to human health’. Sustainable Development Goal 12 also indirectly references the issue of hazardous substances and wastes by calling for ‘sustainable consumption and production patterns’. One of the associated targets for Goal 12 is to achieve, by 2020, ‘the environmentally sound management of chemicals and all wastes throughout their life cycle, in accordance with agreed international frameworks, and significantly reduce their release to air, water and soil in order to minimize their adverse impacts on human health and the environment.’