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Thirty years ago, many toxic and persistent chemicals were considered to be not only resources but also pollutants adversely affecting human health and the environment, particularly where they could be accumulated up the food chain or transported long distances over the globe. Today, chemicals are seen as even more essential to development, and as a resource that needs to be managed to protect or even enhance human health and the environment. This sound management of chemicals applies to both those anthropogenically produced and those of natural origin, including those generated through biological processes.

The international community has recently concluded a landmark convention to control the use of a group of persistent toxic organic compounds (see box). In December, 2000 representatives of 122 governments finalized the text of a legally binding treaty for implementing international action on certain persistent organic pollutants (POPs). The Stockholm Convention on Persistent Organic Pollutants, signed in May 2001 and which had 111 signatories and 2 Parties as of December 2001, sets out control measures covering 12 chemicals. The control provisions call for eliminating production and use of intentionally produced POPs and eliminating unintentionally produced POPs where this is feasible (UNEP 2001).

Stockholm Convention on Persistent Organic Pollutants

The POPs treaty covers an initial list of 12 chemicals, the so-called 'dirty dozen':

  • eight pesticides - aldrin, chlordane, dichlorodiphenyltrichloroethane (DDT), dieldrin, endrin, heptachlor, mirex and toxaphene;
  • two industrial chemicals - polychlorinated biphenyls (PCBs) and hexachlorobenzene (which is also a pesticide); and
  • two unwanted by-products of combustion and industrial processes (dioxins and furans).

A health-related exemption has been granted for DDT, which is still needed in many countries to control malarial mosquitoes until 2025. Governments may also maintain existing equipment that contains PCBs in a way that prevents leaks to give them time to arrange for PCB-free replacements. PCBs have been widely used in electrical transformers and other equipment.

The Convention also designates GEF as its primary financial mechanism, on an interim basis, through which developed countries will channel new and additional resources to help countries with economies in transition and developing countries to implement their obligations. It also provides for a science-based process, incorporating precaution, to review other chemicals for possible addition by the Conference of the Parties.

Source: UNEP 2001

Since the Stockholm Conference, the global chemicals industry has grown almost ninefold and an annual growth rate of about 3 per cent is expected to continue over the next three decades, with a considerable increase in trade (OECD 2001). This will increase the risk of exposing an increasing number of people and the environment to new chemicals and the potential for the emergence of new diseases of chemical origin.

Information about the release of chemicals into the environment is now much more widely available than used to be the case. North America has led action in this area, in particular with the US Toxics Release Inventory (TRI 2001) enacted through the Emergency Planning and Community Right-to-Know Act (EPCRA) in the United States in 1986. EPCRA's purpose is to inform communities and citizens of chemical hazards in their areas. The Act requires businesses to report the locations and quantities of chemicals stored on-site to state and local governments. Through EPCRA, the US Congress mandated that a Toxics Release Inventory (TRI) be made public. TRI provides citizens with information about potentially hazardous chemicals and their use so that communities have more power to hold companies accountable and make informed decisions about how toxic chemicals are to be managed.