Emissions of many persistent organic pollutants are transported across international boundaries and are deposited in Europe, North America and the Arctic, far from their site of origin. The atmosphere is the dominant medium of transport. Persistent organic pollutants can biomagnify in upper trophic levels to concentrations which might affect the health of exposed wildlife and humans. The Arctic ecosystems and especially its indigenous people, who subsist on Arctic fish and mammals, are particularly at risk because of the biomagnification of persistent organic pollutants.
"Persistent organic pollutants" (POPs) are organic substances that: (i) possess toxic characteristics; (ii) are persistent; (iii) bioaccumulate; (iv) are prone to long-range transboundary atmospheric transport and deposition; and (v) are likely to cause significant adverse human health or environmental effects near to and distant from their sources.
The Executive Body adopted the Protocol on Persistent Organic Pollutants on 24 June 1998 in Ã…rhus (Denmark). It focuses on a list of 16 substances that have been singled out according to agreed risk criteria. The substances comprise eleven pesticides, two industrial chemicals and three by-products/contaminants. The ultimate objective is to eliminate any discharges, emissions and losses of POPs.
The basis upon which we are taking action is the global nature of the deposition of the chemicals. It is the transboundary movement of chemicals that creates the need for this treaty. The agreement is designed to address toxic chemicals that, because they persist in the environment, are transported, and bioaccumulate, are likely to result in exposures of concern at sites remote from the point of release. All of the chemicals identified have a variety of toxic endpoints, and the treaty will be designed to include toxic chemicals that exhibit the characteristics of transport, bioaccumulation, and persistence such that they are likely to pose risks in remote sites. In itself this concern is sufficient to warrant global action.
The Protocol bans the production and use of some products outright (aldrin, chlordane, chlordecone (kepone), dieldrin, endrin, hexabromobiphenyl, mirex and toxaphene). Others are scheduled for elimination at a later stage (DDT, heptachlor, hexachlorobenzene, PCBs). Finally, the Protocol severely restricts the use of DDT, HCH (including lindane) and PCBs. The Protocol includes provisions for dealing with the wastes of products that will be banned. It also obliges Parties to reduce their emissions of dioxins, furans, PAHs and HCB below their levels in 1990 (or an alternative year between 1985 and 1995). For the incineration of municipal, hazardous and medical waste, it lays down specific limit values.
Addressing these chemicals is in every country's interest. For example, industrializing countries that are the most likely to be spewing large amounts of dioxins are also the ones who will benefit the most from action.