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The uncertainty and variability in the dose–response relationship of dioxins in terms of their toxicity, as well as the ability of dioxins to bioaccumulate, have led WHO experts to recommending very low tolerable daily intake (TDI) of dioxin, 1-4 pg/kg body weight per day, i.e. 7x10 −11 to 2.8x10 −10 g per 70-kg person per day, to allow ...
2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) is the reference chemical to which the toxicity of other dioxins and DLCs are compared. TCDD is the most toxic DLC known. Other dioxins and DLCs are assigned a scaling factor, or TEF, in comparison to TCDD. TCDD has a TEF of 1.0. Sometimes PCB 126 is also used as a reference chemical, with a TEF of 0.1.
By far most information on toxicity of dioxin-like chemicals is based on animal studies utilizing TCDD. [4] [8] [35] [36] Almost all organs are affected by high doses of TCDD. In short-term toxicity studies in animals, the typical effects are anorexia and wasting, and even after a huge dose animals die only 1 to 6 weeks after the TCDD ...
Other dioxin congeners including PCDFs and PCBs with dioxin-like toxicity, are given a toxicity rating from 0 to 1, where TCDD = 1 (see Dioxins and dioxin-like compounds). This toxicity rating is called the Toxic Equivalence Factor concept, or TEF. TEFs are consensus values and, because of the strong species dependence for toxicity, are listed ...
Dioxins and dioxin-like compounds, a diverse class of polychlorinated chemical compounds, including polychlorinated dibenzodioxins (PCDDs) and dibenzofurans (PCDFs), that are persistent organic pollutants and known to exhibit "dioxin-like" toxicity.
An ECG showing digoxin toxicity with the classic "scooped out" ST segment. In digoxin toxicity, the finding of frequent premature ventricular beats (PVCs) is the most common and the earliest dysrhythmia. Sinus bradycardia is also very common. In addition, depressed conduction is a predominant feature of digoxin toxicity.
Contamination by dioxins — toxic chemicals known to cause cancer, disrupt the immune system and cause reproductive harms — have been at the center of notorious environmental cleanups from ...
Its toxicity is similar to TCDD, but it is about 3000 times weaker. [1] It is one of the dominant dioxin congeners in smoke emissions, but because it is much less soluble than e.g. TCDD, it is not bioaccumulated as effectively and it is toxicologically less important than the most prevalent dioxins. (for details see Dioxins and dioxin-like ...