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The NOAEL is determined or proposed by qualified personnel, often a pharmacologist or a toxicologist. [citation needed] The NOAEL could be defined as "the highest experimental point that is without adverse effect," meaning that under laboratory conditions, it is the level where there are no side-effects. It either does not provide the effects ...
LOAEL is lowest-observed-adverse-effect-level. It is the minimum dose of a substance that produces an observable adverse effect on the treated group in human clinical trials or animal experimental trials. [3] There is a biologically or statistically significant increase in the prevalence of adverse effect in the treated group above this level. [10]
A proposed alternative is the use of so-called ECx – the concentration(s) showing x% effect (e.g. an EC 50 in a survival experiment indicates the concentration where 50% of the test animals would die in that experiment). ECx concentrations also have their problems in applying them to risk assessment.
Cholinesterase inhibition was observed at all dose levels tested, and a NOAEL of 0.03 mg/kg/day estimated by dividing a LOAEL of 0.3 mg/kg/day by an uncertainty factor of 10. As with the acute RfD, the chronic RfD of 3×10 −4 mg/kg/day was determined by dividing this NOAEL by the inter- and intraspecies uncertainty factors.
Acceptable daily intake or ADI is a measure of the amount of a specific substance (originally applied for a food additive, later also for a residue of a veterinary drug or pesticide) in food or drinking water that can be ingested (orally) daily over a lifetime without an appreciable health risk. [1]
The lowest-observed-adverse-effect level (LOAEL), or the lowest-observed-adverse-effect concentration (LOAEC), is the lowest concentration or amount of a substance found by experiment or observation that causes an adverse alteration of morphology, function, capacity, growth, development, or lifespan of a target organism distinguished from normal organisms of the same species under defined ...
The derived no-effect level (DNEL) is the level of exposure to a substance above which humans should not be exposed. The REACH regulation defines them as exposure levels beneath which a substance does not harm human health. [ 1 ]
An Measured Environmental Concentration (MEC) relates to a chemical substance found in an environmental sample. The concentration of the compound may result from direct contamination, transformation and/or metabolization of a different chemical contaminant, natural origin or a combination of these sources.