Persistent organic pollutants (POPs) are a class of chemicals that persist in the environment, are capable of long-range transport, bioaccumulate in human and animal tissue, and have significant impacts human health and the environment. They include such substances as dioxin, PCBs, DDT, brominated flame-retardants or tributyltin (TBT). POPs released to the environment can travel through air and water to regions far distant from their original source. A chemical substance is any material substance used in or obtained by a process in chemistry: A chemical compound is a substance consisting of two or more chemical elements that are chemically combined in fixed proportions. ... Persistence is the term used in computer science to describe a capability used by a computer programmer to store data structures in non-volatile storage such as a file system or a relational database. ... To bioaccumulate literally means to accumulate in a biological system. ... A biological tissue is a group of biological cells that perform a similar function. ... Health can be defined negatively, as the absence of illness, functionally as the ability to cope with everyday activities, or positively, as fitness and well-being (Blaxter 1990). ... Dioxins form a family of toxic chlorinated organic compounds that bioaccumulate in humans and wildlife due to their fat solubility. ... Labelling transformers containing PCBs Polychlorinated biphenyls (PCBs) are a class of organic compounds with 1 to 10 chlorine atoms are attached to biphenyl and a general structure of C12H10-xClx. ... DDT was the first modern pesticide and is arguably the most well known inorganic pesticide. ...
The general trend of POPs is the following:
Synthesis/development.
Increased use over large areas in Europe and North America.
Concerns over their persistence, bioaccumulation and bioconcentration.
Tinctures are the colours used to blazon coats of arms in heraldry. ... Food chains and food webs describe the feeding relationships between species in a biotic community. ... Stockholm Convention is an international agreement on persistent organic pesticides. ...
External links
Greenpeace: Chemicals out of control (http://www.greenpeace.org/international/campaigns/toxics/chemicals-out-of-control/)
Stockholm Convention on Persistent Organic Pollutants (http://www.pops.int/)
POPs tend to bioaccumulate in food chain to levels 10,000 to 100,000 times higher than the levels found at low trophic levels, and tend to persist in the environment without significantly degrading.
PCBspersist in fat and in the environment, and were used from 1935-1976 in the U.S. as coolants, flame retardants, lubricants, sealants.
POPs are a group of very heterogeneous chemicals that are related by their pharmacokinetics, and the way they behave in the body and environment.
Many measurements of organic contaminants have been made because of concern about high intake by people, and the human health aspects of these substances are discussed in the chapter Pollution and Human Health.
PersistentOrganicPollutants (POPs) are chemical substances that persist in the environment, bioaccumulate through the food web, and pose a risk of causing adverse effects to human health and the environment.
PBT pollutants are chemicals that are toxic, persist in the environment and bioaccumulate in food chains and, thus, pose risks to human health and ecosystems.
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