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Polybrominated biphenyls (PBBs), also called brominated biphenyls or polybromobiphenyls, are a group of manufactured chemicals. While once widely used commercially, PBBs are now controlled substances under the Restriction of Hazardous Substances Directive. See the Wikipedia:Legal disclaimer. ...
Characteristics
PBBs usually exist as colorless to off-white solids. Its notable characteristics include: The degree Celsius (°C) is a unit of temperature named after the Swedish astronomer Anders Celsius (1701–1744), who first proposed it in 1742. ...
Vapor pressure is the pressure of a vapor in equilibrium with its non-vapor phases. ...
Ultraviolet (UV) radiation is electromagnetic radiation of a wavelength shorter than that of the visible region, but longer than that of soft X-rays. ...
Benzene, also known as benzol, is an organic chemical compound with the formula C6H6. ...
Toluene, also known as methylbenzene or phenylmethane is a clear, water-insoluble liquid with the typical smell of paint thinners, reminiscent of the sweet smell of the related compound benzene. ...
Impact of a drop of water. ...
Application PBBs are used as flame retardants of the brominated flame retardant group. They are added to plastics used in products such as home electrical appliances, textiles, plastic foams etc. to make them difficult to burn. Flame retardants are materials that inhibit or resist the spread of fire. ...
Brominated flame-retardants are produced synthetically in ca 70 variants with very varying chemical properties. ...
To meet Wikipedias quality standards, this article or section may require cleanup. ...
Health hazards Most of our knowledge about the effects of PBBs on human beings came from studies of people in Michigan, USA who consumed PBB-contaminated animal products (see history of PBBs below). Some residents complained of nausea, abdominal pain, loss of appetite, joint pain and lethargy, though it could not be clearly established that PBBs were the cause of these health problems. Human beings are defined variously in biological, spiritual, and cultural terms, or in combinations thereof. ...
Official language(s) None (English, de-facto) Capital Lansing Largest city Detroit Area Ranked 11th - Total 97,990 sq mi (253,793 km²) - Width 239 miles (385 km) - Length 491 miles (790 km) - % water 41. ...
For other uses, see Nausea (disambiguation). ...
Abdominal pain can be one of the symptoms associated with transient disorders or serious disease. ...
Anorexia (deriving from the Greek ÏŒÏεξη (orexe) = appetite) is the decreased sensation of appetite. ...
In medicine, arthralgia (literally: joint pain, from arthros = joint and -algia denoting pain) is the presence of painful joints in the absence of frank arthritis. ...
Fatigue is a feeling of excessive tiredness or lethargy, with a desire to rest, perhaps to sleep. ...
There is stronger evidence that PBBs may have caused skin problems, such as acne, in consumers of the contaminated food. Some workers exposed to PBBs by breathing and skin contact for days to months also developed acne.
Studies in animals exposed to large amounts of PBBs for a short period or to smaller amounts over a longer period show that PBBs can cause weight loss, skin disorders, nervous and immune systems effects, as well as effects on the liver, kidneys, and thyroid gland. To meet Wikipedias quality standards, this article or section may require cleanup. ...
The nervous system of an animal coordinates the activity of the muscles, monitors the organs, constructs and also stops input from the senses, and initiates actions. ...
The immune system is composed of a complex constellation of cells, organs and tissues, arranged in an elaborate and dynamic communications network and equipped to optimize the response against invasion by pathogenic organisms. ...
The liver is the largest internal organ of the human body. ...
Human kidneys viewed from behind with spine removed The kidneys are bean-shaped excretory organs in vertebrates. ...
The thyroid gland and its relations In anatomy, the thyroid (IPA θaɪɹoɪd) is an endocrine gland. ...
Carcinogen It is not known for certain if PBBs could cause cancer in human beings, but it has been observed that they can lead to cancer in lab mice exposed to very high concentrations of PBBs. Based on such animal tests, the United States Department of Health and Human Services has determined that PBBs may reasonably be anticipated to be carcinogens. The International Agency for Research on Cancer also suggests that PBBs are possibly carcinogenic to humans. Cancer is a class of diseases or disorders characterized by uncontrolled division of cells and the ability of these cells to invade other tissues, either by direct growth into adjacent tissue through invasion or by implantation into distant sites by metastasis. ...
Binomial name Mus musculus Linnaeus, 1758 Mus musculus is the common house mouse. ...
The United States Department of Health and Human Services, often abbreviated HHS, is a Cabinet department of the United States government with the goal of protecting the health of all Americans and providing essential human services. ...
In pathology, a carcinogen is any substance or agent that promotes cancer. ...
The International Agency for Research on Cancer (IARC, or CIRC in its French acronym) is an intergovernmental agency forming part of the World Health Organisation of the United Nations. ...
History Before the 1970s, PBBs were widely used commercially as a flame retardant. In 1973, however, several thousand pounds of PBBs were accidentally mixed with livestock feed that was distributed to farms in West Central Michigan, USA. Some 1.5 million chickens, 30,000 cattle, 5,900 pigs, and 1,470 sheep had become contaminated with PBBs before the error was discovered. Flame retardants are materials that inhibit or resist the spread of fire. ...
The pound is the name of a number of units of mass, all in the range of 300 to 600 grams. ...
Official language(s) None (English, de-facto) Capital Lansing Largest city Detroit Area Ranked 11th - Total 97,990 sq mi (253,793 km²) - Width 239 miles (385 km) - Length 491 miles (790 km) - % water 41. ...
Trinomial name Gallus gallus domesticus A chicken (Gallus gallus domesticus) is a type of domesticated bird which is often raised as a type of poultry. ...
Binomial name Bos taurus Linnaeus, 1758 Cattle (called cows in vernacular and contemporary usage, kine or kyne in pre-modern English, or kye as the Scots plural of cou) are domesticated ungulates, a member of the subfamily Bovinae of the family Bovidae. ...
Species Sus barbatus Sus bucculentus Sus cebifrons Sus celebensis Sus domesticus Sus heureni Sus philippensis Sus salvanius Sus scrofa Sus timoriensis Sus verrucosus Pigs are ungulates native to Eurasia collectively grouped under the genus Sus within the Suidae family. ...
Species See text. ...
Although these animals were promptly culled, a study was undertaken on 4,545 people to determine the effects of PBBs on human beings. These include three exposure groups – all people who lived on the quarantined farms, people who received food from these farms and workers (and their families) engaged in PBB manufacture – as well as 725 people with low-level PBB exposure. Human beings are defined variously in biological, spiritual, and cultural terms, or in combinations thereof. ...
All were queried concerning 17 symptoms and conditions possibly related to PBBs. Venous blood was drawn and analyzed for PBB by gas chromatography. Mean serum PBB levels were found to be 26.9 ppb by weight (26.9 µg/kg) in farm residents, 17.1 in recipients, 43.0 ppb in workers, and 3.4 ppb in the low exposure group. No associations could be established between serum PBB levels and symptom prevalence rates. In the circulatory system, venous blood is blood returning to the heart. ...
Gas-liquid chromatography (GLC), or simply gas chromatography (GC) is a type of chromatography in which the mobile phase is a carrier gas, usually an inert gas such as helium or nitrogen, and the stationary phase is a microscopic layer of liquid on an inert solid support. ...
Blood plasma is the liquid component of blood, in which the blood cells are suspended. ...
Parts per billion (ppb) is a measure of concentration that is used where low levels of concentration are significant. ...
To evaluate peripheral lymphocyte function, T and B cell quantitation and in vitro responses to three nonspecific mitogens were studied in 34 persons with highest PBB levels (mean: 787 ppb), and in 56 with low levels (mean: 2.8 ppb). Again, no statistically significant differences in lymphocyte function were noted. A lymphocyte is a type of white blood cell involved in the human bodys immune system. ...
T cells are a subset of lymphocytes that play a large role in the immune response. ...
B cells are lymphocytes that play a large role in the humoral immune response (as opposed to the cell-mediated immune response). ...
Wiktionary has a definition of: In vitro In vitro (Latin: within glass) means within a test tube, or, more generally, outside a living organism or cell. ...
A mitogen is a substance that causes a cell to begin dividing. ...
Noting the possible hazards on the environment, however, PBBs were listed as controlled substances under the Restriction of Hazardous Substances Directive, which was enacted into European Law in February 2003. See the Wikipedia:Legal disclaimer. ...
The European Union is unique among international organizations in having a complex and highly developed system of internal law which has direct effect within the legal systems of its member states. ...
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