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Dibenzofuran is a relatively non-toxic compound as evidenced by rats being unaffected after a 200-day diet consisting of 0.025 – 0.4% of DBF. [1] The polychlorinated dibenzofurans are however among the potentially toxic dioxins and dioxin-like compounds .
Polychlorinated dibenzofurans with chlorines at least in positions 2,3,7 and 8 are much more toxic than the parent compound dibenzofuran, with properties and chemical structures similar to polychlorinated dibenzodioxins. These groups together are often inaccurately called dioxins.
2,3,7,8-Tetrachlorodibenzofuran (TCDF) is a polychlorinated dibenzofuran with a chemical formula of C 12 H 4 Cl 4 O. TCDF is part of the chlorinated benzofuran (CDF) family that contains between 1 and 8 chlorine atoms attached to the parent dibenzofuran ring system. The CDF family includes 135 compounds, of which only a few have been studied.
TCDD also affects the balance of several hormones. In some species, but not in all, severe liver toxicity is seen. [8] [36] Taking into account the low doses of dioxins in the present human population, only two types of toxic effects have been considered to cause a relevant risk to humans: developmental effects and cancer. [3] [8]
Some content in this article was extracted from Dioxins and dioxin-like compounds: toxicity in humans and animals, sources, and behaviour in the environment at the Wikiversity, which is licensed under the Creative Commons Attribution-Share Alike 3.0 (Unported) (CC-BY-SA 3.0) license.
Today, concentrations of dioxins are found in all humans, with higher levels commonly found in persons living in more industrialized countries. The most toxic dioxin, 2,3,7,8-tetrachlorodibenzodioxin (TCDD), became well known as a contaminant of Agent Orange, a herbicide used in the Malayan Emergency and the Vietnam War. [11]
The toxicity of the individual congeners may vary by orders of magnitude. With the TEFs, the toxicity of a mixture of dioxins and dioxin-like compounds can be expressed in a single number – the toxic equivalency (TEQ). It is a single figure resulting from the product of the concentration and individual TEF values of each congener. [1]
Toxic to cardio and central nervous systems, gastrointestinal bleeding [3] Ephedra: ma huang: Ephedra sinica: Agitation and palpitations, [3] "hypertension, irregular heart rate, insomnia, nervousness, tremors and seizures, paranoid psychosis, heart attacks, strokes, and death", [1] [15] kidney stones [15] Flavonoids (contained in many ...