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If the result of a study is a toxic effect that does not result in death, it is classified as this form of toxicity. [2] Toxic effects can be defined differently, sometimes considering the therapeutic effect of a substance to be toxic (such as with chemotherapeutics) which can lead to confusion and contention regarding a substance's TD 50 ...
The value of LD 50 for a substance is the dose required to kill half the members of a tested population after a specified test duration. LD 50 figures are frequently used as a general indicator of a substance's acute toxicity. A lower LD 50 is indicative of higher toxicity. The term LD 50 is generally attributed to John William Trevan. [2]
The goal of toxicity assessment is to identify adverse effects of a substance. [15] Adverse effects depend on two main factors: i) routes of exposure (oral, inhalation, or dermal) and ii) dose (duration and concentration of exposure). To explore dose, substances are tested in both acute and chronic models. [16]
In toxicology, the lethal dose (LD) is an indication of the lethal toxicity of a given substance or type of radiation.Because resistance varies from one individual to another, the "lethal dose" represents a dose (usually recorded as dose per kilogram of subject body weight) at which a given percentage of subjects will die.
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.
Toxication, toxification or toxicity exaltation is the conversion of a chemical compound into a more toxic form in living organisms or in substrates such as soil or water. The conversion can be caused by enzymatic metabolism in the organisms, as well as by abiotic chemical reactions .
The term "environmental toxin" can sometimes explicitly include synthetic contaminants [26] such as industrial pollutants and other artificially made toxic substances. As this contradicts most formal definitions of the term "toxin", it is important to confirm what the researcher means when encountering the term outside of microbiological contexts.
U.S. Army Public Health Center Toxicology Lab technician assessing samples. Toxicology testing, also known as safety assessment, or toxicity testing, is the process of determining the degree to which a substance of interest negatively impacts the normal biological functions of an organism, given a certain exposure duration, route of exposure, and substance concentration.