ld50 definition pharmacology

Alternative Titles: LD50, lethal dose 50. Acute toxicity refers to those adverse effects occurring following oral or dermal administration of a single dose of a substance, or multiple doses given within 24 hours, or an inhalation exposure of 4 hours.

The term effective dose is used when measurements are taken in vivo, while the term effective concentration is used when the measurements are taken in vitro.. LD50 is a measurement used in toxicology studies to determine the potential impact of toxic substances on different types of organisms.

pharmacology.

This relationship is defined as the ratio LD50:ED50.

True Bugs, Aphids, Cicadas, and Hoppers …

In drug: Dose-response relationship …result being expressed as the median lethal dose (LD 50), which is defined as the dose causing mortality in 50 percent of a group of animals.

Most Toxic Insect Venom.

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Toxicity ratings for chemicals are based on their LD50s.

In pharmacology, an effective dose (ED) or effective concentration (EC) is a dose or concentration of a drug that produces a biological response.

Get kids back-to-school ready with Expedition: Learn! These are parameters for different chemical compounds which describe the amount of a substance that can cause death.

Learn about this topic in these articles: drug action. The LD50 measurement is usually expressed as the amount of toxin

lethal dose 50 (LD50): Standard measure of the toxicity of a material that will kill half of the sample population of a specific test animal in a specified period through exposure via ingestion, skin contact, or injection. Chemicals can be allocated to one of five toxicity categories based on acute toxicity by the oral, dermal or …

The toxicity rating indicates the amount of chemical required to produce death, but it should be remembered that all chemicals can kill.

The lethal concentration is a lethal dose measurement …

More important than the toxicity of a chemical…

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. LD50 definition is - the amount of a toxic agent (such as a poison, virus, or radiation) that is sufficient to kill 50 percent of a population of animals usually within a certain time.

Reference: W.L.

Read More; poisons and poisoning.

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It provides an objective measure to compare and rank the toxicity of substances. Thus, all chemicals are toxic. What Is the Most Poisonous Chemical Compound? Be on the lookout for your Britannica newsletter to get trusted stories delivered right to your inbox.

Insect and spider venoms can also be compared using LD50 measurements, to determine which venoms are the most deadly to a given population of organisms. Pesticide studies involve LD50 testing, usually on rats or mice and on dogs. By signing up for this email, you are agreeing to news, offers, and information from Encyclopaedia Britannica.

The terms LD50 and LC50 are found mainly in toxicology.

The toxins might be introduced orally, through injection, or inhaled.

Chapter 23 in University of Florida Book of Insect Records, 2001. http://entomology.ifas.ufl.edu/walker/ufbir/. It provides an objective measure to compare and rank the toxicity of substances.

…result being expressed as the median lethal dose (LD Because this testing kills a large sample of the animals, it is now being phased out in the United States and some other countries in favor of newer, less lethal methods. It has been stated that any substance can be toxic at a high …

The LD50 measurement is usually expressed as the amount of toxin per kilogram or pound of body weight. The median lethal dose of a substance, or the amount required to kill 50% of a given test population. DEFINITIONS 1.

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In poison: Dose of exposure …the lethal dose 50, or LD50.

LD50 is a measurement used in toxicology studies to determine the potential impact of toxic substances on different types of organisms.

…the lethal dose 50, or LD50.

Therapeutic index, margin of safety that exists between the dose of a drug that produces the desired effect and the dose that produces unwanted side effects. The LD50 test involves exposing a population of test animals, typically mice, rabbits, guinea pigs, or even larger animals such as dogs, to the toxin in question.

In general, the narrower this margin, the more likely the drug is to produce unwanted side effects.

Debbie Hadley is a science educator with 25 years of experience who has written on science topics for over a decade.

CLASSIFICATION CRITERIA FOR SUBSTANCES 2. Lethal dose (expressed as LD 50, the estimated dose required to kill 50% of a group of experimental animals) has been largely abandoned as a useful measure of toxicity, and no longer needs to be measured for new compounds.Measures commonly used are: • no toxic effect level (NTEL), which is the largest dose in the most sensitive species in a toxicology study of a given …