|
|
Current trends
- Persistent organic pollutants (POPs) are chemical substances that resist natural breakdown processes and bioaecumulate
in fatty tissues at different levels of the food chain. POPs also are semi-volatile, enabling them to move long distances in
the atmosphere.
- The ability of POPs to persist in the environment and travel long distances has resulted in the presence of POPs all over
the world, even in regions where they have never been used.
- Most of the twelve POPs currently addressed in international negotiations have been banned or subjected to severe use
restrictions in many countries for more than 20 years. Many of them, however, are still in use in many countries, and
stockpiles of obsolete POPs exist in many parts of the world.
Underlying causes of issue
- POPs comprise a large number of chemicals that have a wide range of uses. The twelve targeted POPs are used prima-
rily in industry, agriculture, and disease vector control. Nine of them are pesticides used for crops and/or public health
vector control (e.g., control of malaria-carrying mosquitoes).
- POPs can be produced cheaply compared to most other industrial chemicals.
Social and economic consequences of use of POPs
- Humans can be exposed to POPs through diet, occupational accidents, and the environment. Exposure to very low
doses of certain POPs can lead to cancer, damage to the central and peripheral nervous systems, diseases of the immune
system, reproductive disorders, and interference with infant and child development.
- Human health impacts may be felt most acutely in populations that consume large amounts of fish (e.g., subsistence
fishermen), since fish have a high fat content and thus can contain high concentrations of POPs.
- The accumulation of obsolete stockpiles of pesticides and toxic chemicals (particularly common in developing countries)
can cause leaching of these chemicals into the soil, contaminating water resources used by both wildlife and people.
Technologies, policies, and measures for shifting to safer alternatives
- There is sufficient evidence of harm to wildlife and humans to demonstrate that international action is required to
reduce the risk of POPs to health and environment.
- Shifting from POPs to chemical and non-chemical alternatives is the key to reducing the impact of these hazardous
substances. A high priority is finding alternatives to hazardous chemicals for insect control.
- There are many safer chemical and non-chemical alternatives, but their development and dissemination will require
time, money, and training. For example, replacing DDT (widely used to control malarial mosquitoes) with less-hazard-
ous forms of insect control requires time to plan effective actions (e.g., integrated pest management systems, consisting
of the sparing use of pest-specific pesticides and biological control methods).
- Many countries face barriers to identifying and controlling releases of POPs. These include high prices of some alterna-
tives, the need for education and training on the hazardous nature of POPs, a lack of information on what alternatives
are available, a lack of reliable data about the current uses of POPs in each country, and the need for regulations/
infrastructure to manage the use of pesticides. In many cases, technology transfer and development assistance are
needed to bring replacements into widespread use.
Status of international agreements
- Because of the global risks posed by the long-range transport of POPs, the international community is calling for global
action to reduce and eliminate releases of these chemicals.
- The United Nations Environment Programme (UNEP) is leading the development of a global legally-binding agreement
to minimize releases of POPs into the environment. The first meeting on such an agreement was held in Montreal in
June 1998. The second round of talks is tentatively scheduled for early 1999, and the negotiations are expected to
conclude by the year 2000.
- Twelve specific POPs are internationally recognized as requiring elimination and reduction: aldrin, chlordane, DDT,
dieldrin, dioxins, endrin, furans, heptachlor, hexachlorobenzene, mirex, PCBs, and toxaphene. Scientific criteria will be
developed for identifying other POPs that may be added to the list later.
- UNEP also has initiated actions on sharing information, evaluating and monitoring implemented strategies, alternatives
to POPs, identification and inventories of PCBs, available destruction capacity, and other issues. UNEP and the Intergov-
ernmental Forum on Chemical Safety (IFCS) also are convening awareness-raising workshops in developing countries
and countries with economies in transition.
Source:
"Protecting Our Planet, Securing Our Future" UNEP / U.S. NASA / World Bank, 1997
|