Chapter 3 (Frish) Flashcards
basic assumption in toxicology
all substances are poison, there is none that is not a poison, the right dose differentiates a poison from a remedy
exposure
proximity and/or contact with a source of a disease agent in such. manner that effective transmission of the agent or harmful effects of the agent may occur
environmental toxicology
the study of the impacts of pollutants upon the structure and function of ecological systems
ecotoxicology
is concerned with the effects of pollutants on ecosystems
xenobiotics
chemical substances that are foreign to the biological system - example is polychlorinated biphenyls (PCBs)
poison
any agent capable of producing a deleterious response in a biological system
toxic agent
refers very generally to a material or factor that can be harmful to biological systems
toxicity
the degree to which something is poisonous
toxic substance
a material that has toxic properties
- organic toxins denote substances originally taken from living organisms, carbon containing chemicals, made up of large molecules, and capable of being synthesised
- inorganic toxins refer to specific chemicals, such as minerals that have not been extracted from living organisms and do not follow the structure of a toxin derived from a living organism, such toxins generally are made up of small molecules (usually do not contain carbon)
toxicant
denote toxic substances that are man-made or result from human activity
- toxic affect might occur directly or indirectly
toxin
usually refers to a toxic substance made by living organisms including reptiles, insects, plants, and microorganism
- systemic toxins are those that affect the entire body or multiple organ systems
- target organ toxins affect specific parts of the body
dose
the amount of a substance administered at one time
exposure dose
the amount of a xenobiotic encountered in the environment
external dose
a dose that results from contact with environmental sources, e.g., environmental contamination
