Toxicology Flashcards

Vocabulary flashcards about toxicology

Toxicology

The study of adverse effects of chemical, physical and biological agents on living organisms.

Toxicity

The ability of a substance to cause injury to the biologic material.

Poison

Any agent capable of providing deleterious effects in a biological system seriously injuring function or causing death.

Xenobiotic

Substance not naturally produced within an organism. May be beneficial (Medicines) and Toxic (Lead).

Toxin

Poisonous substance produced by plants, animals or microorganisms (Tetanus toxin).

Toxicant

Agent capable of producing symptoms of intoxication or poisoning (Fish- picrotoxin).

Poisoning

An overdose of drugs, medicaments, chemicals and biological substances (APAP overdose- hepatotoxicity).

Risk

Potential (Likelihood) that an injury (Biological damage) can happen.

Exposure

Amount of chemical that is available for absorption.

Safety

Probability that harm will not occur in certain conditions (Opposite of risk).

Systemic Toxin

It affects the entire body or many organs. Ex: Potassium Cyanide- Interferes the cell to utilize oxygen

Organ Toxins

Affects specific tissues or organs only but not the whole body. Ex: Benzene- Blood forming tissues Lead- CNS, Kidneys, Hematopoeitic system

Organic Toxins

Derived from living organisms, large molecules (Carbon), can be synthesized or naturally acquired.

Inorganic Toxins

Small molecules of few atoms (Nitrogen dioxide).

Acute Exposure

Is the condition wherein the animal is exposed to a chemical for less than 24 hours usually as a single dose or in divided doses within 13 hours; for the inhalational route, exposure is continuous for 4 hours

Subacute Exposure

Involves repeated daily exposure of the animal to the chemical for less than one month (usually 21 days) by a specific route

Subchronic Exposure

Involves repeated daily exposure of the animal to the chemical for 90 days or 3 months

Chronic Exposure

The animal is exposed to the chemical throughout its lifetime: for 2 years in rats and mice, or even longer for dogs and non-human primates

Dose

Amount of a substance administered at one time. (Number of doses, frequency, total time period of treatment).

Threshold Dose

Dose level at which the toxic effect was first encountered.

Subthreshold Dose

Doses below the threshold dose.

Exposure Dose

Amount of xenobiotic encountered in the environment.

Absorbed Dose

Actual amount of exposed dose that entered the body.

Administered Dose

Quantity given at any route of administration.

Total Dose

Sum of all individual doses.

Threshold

The dose at which the first response is observed as a result of toxicity testing; below this dose, no responses are observed

Acute Toxicity

Occur immediately after exposure (Hours/Days) Ex: Venom of a snake bite

Subchronic Toxicity

Resulted from repeated exposure (Months/Years). Ex: Lung fibrosis from asbestos exposure

Chronic Toxicity

Cumulative damage to specific organ systems, takes months or years to become clinically recognizable. Ex: Lung Cancer due to chronic smoking

Embryolethality

Failure to conceive, spontaneous abortion (Stillbirth).

Embryotoxocity

Growth retardation and organ growth delay.

Teratogenicity

Irreversible conditions leaving permanent birth defects on live offspring. (Cleft palate, Phocomelia).