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Following the release of the paper, Science published a “News of the week” article by Constance Holden. [4] The article noted that the results of the study had caused the researchers concern that even a single night of MDMA usage could cause brain damage, and leave a person vulnerable to neurological disorders such as Parkinson's disease.
Acute toxicity is distinguished from chronic toxicity, which describes the adverse health effects from repeated exposures, often at lower levels, to a substance over a longer time period (months or years). It is widely considered unethical to use humans as test subjects for acute (or chronic) toxicity research.
Toxicity is the degree to which a chemical substance or a particular mixture of substances can damage an organism. [1] Toxicity can refer to the effect on a whole organism, such as an animal, bacterium, or plant, as well as the effect on a substructure of the organism, such as a cell (cytotoxicity) or an organ such as the liver (hepatotoxicity).
The magic bullet is a scientific concept developed by the German Nobel laureate Paul Ehrlich in 1907. [1] While working at the Institute of Experimental Therapy (Institut für experimentelle Therapie), Ehrlich formed an idea that it could be possible to kill specific microbes (such as bacteria), which cause diseases in the body, without harming the body itself.
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 ...
The toxic effects are related to single chemical exposure; The toxic effects are on an aquatic or terrestrial plant or animal species; There is a biological effect on live, whole organisms; A concurrent environmental chemical concentration/dose or application rate is reported; and; There is an explicit duration of exposure.
Single ascending dose (Phase Ia): In single ascending dose studies, small groups of subjects are given a single dose of the drug while they are observed and tested for a period of time to confirm safety. [8] [14] Typically, a small number of participants, usually three, are entered sequentially at a particular dose. [13]
The threshold dose is only a measure of acute toxicity since the drug or toxic substance investigated is administered at once. The consequence of long-term administration remains unknown. [27] As the threshold dose is the measured minimal response, its accuracy heavily depends on the machinery used. It is possible that further refinement is ...