Persistent organic pollutant



Persistent organic pollutants (POPs) are organic compounds that are resistant to environmental degradation through chemical, bioaccumulate in human and animal tissue, biomagnify in food chains,[1] and to have potential significant impacts on human health and the environment.

In May 1995, the United Nations Environment Programme Governing Council (GC) decided to begin investigating POPs, initially beginning with a short list of the following twelve POPs, known as the 'dirty dozen'[2]: aldrin, polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans, and toxaphene.[1]

Since then, this list has generally been accepted to include such substances as carcinogenic tributyltin (TBT).

The groups of compounds that make up POPs are also classed as PBTs (Persistent, Bioaccumulative and Toxic) or even TOMPs (Toxic Organic Micro Pollutants.)

Many POPs are currently or were in the past used as pharmaceuticals.[1] Though there are a few natural sources of POPs, most POPs are created by humans in industrial processes, either intentionally or as byproducts.[1]

Chemical properties

Some of the chemical characteristics of POPs include low water bioaccumulate in the fatty tissues of living organisms.[1]

Long-range transport

POPs released to the environment have been shown to travel vast distances from their original source. Due to their chemical properties, many POPs are semi-volatile and insoluble. These compounds are therefore unable to transport directly through the environment.[citation needed] The indirect routes include attachment to particulate matter, and through the food chain. The chemicals' semi-volatility allows them to travel long distances through the atmosphere before being deposited.[1] Thus POPs can be found all over the world, including in areas where they have never been used and remote regions such as the middle of oceans and Antarctica.[1] The chemicals' semi-volatility also means that they tend to volatilize in hot regions and accumulate in cold regions, where they tend to condense and stay.[1] PCBs have been found in precipitation.[1]

The ability of POPs to travel great distances is part of the explanation for why countries that banned the use of specific POPs are no longer experiencing a decline in their concentrations; the wind may carry chemicals into the country from places that still use them.[3]

Health concerns

Exposure to POPs can take place through diet, environmental exposure, or accidents.[1] POP exposure can cause death and illnesses including disruption of the endocrine, reproductive, and immune systems; neurobehavioral disorders; and cancers possibly including breast cancer.[1]

The lipid solubility of POPs allows them to bioaccumulate in fatty tissues of animals.[1] Many of the first generation organochlorine insecticides such as DDT were particularly noted for this characteristic.[1]

A study published in 2006 indicated a link between blood serum levels of POPs and Agent Orange (which contained the POP dioxin) in the Vietnam War.[4]


See also

  • Center for International Environmental Law (CIEL)
  • Food chain
  • International POPs Elimination Network (IPEN)
  • Stockholm Convention

References

  1. ^ a b c d e f g h i j k l m n o p q r Ritter L, Solomon KR, and Forget J, Stemeroff M, and O'Leary C. Persistent organic pollutants: An Assessment Report on: DDT, Aldrin, Dieldrin, Endrin, Chlordane, Heptachlor, Hexachlorobenzene, Mirex, Toxaphene, Polychlorinated Biphenyls, Dioxins and Furans. Prepared for The International Programme on Chemical Safety (IPCS), within the framework of the Inter-Organization Programme for the Sound Management of Chemicals (IOMC). Retrieved on September 16, 2007.
  2. ^ The 12 chemicals that the Stockholm Convention focuses on eliminating or reducing[1]. Retrieved on December 17, 2007
  3. ^ United Nations Economic Commission for Europe (May 1996), Interview with Mr. Lars Nordberg. Unece.org. Retrieved on September 18, 2007.
  4. ^ a b c Lee DH, Lee IK, Song K, Steffes M, Toscano W, Baker BA, and Jacobs DR Jr. (2006), A Strong Dose-Response Relation Between Serum Concentrations of Persistent Organic Pollutants and Diabetes. Diabetes Care, 29:1638-1644. PMID 16801591. Retrieved on September 16, 2007.
  5. ^ Living on Earth: POPsible Nightmare. Living on Earth and World Media Foundation (2006). Retrieved on 2007-09-16.
 
This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "Persistent_organic_pollutant". A list of authors is available in Wikipedia.