OHS 322 Lecture 2: OHS322Lecture2

• School: Ryerson University
• Department: Occupational Health
• Course: OHS 322
• Professor: Eric Liberda

Document Summary

Definitions in toxicology: toxicity: intrinsic property of the chemical to cause damage, hazard: the potential of a substance to do harm, risk: probability that someone will become ill from exposure. Xenobiotic: is a chemical which is found in an organism but which is not normally produced to be presented in it. Toxicant: is used in speaking of toxic substances that are produced by or are a by-product of anthropogenic (human-made) activities. Toxin: generally refers to toxic substances that are produced by biological systems such as plants, animals, fungi, or bacteria. Pattern of exposure described by two elements: duration and frequency. Acute exposure acute toxicity (methanol) (higher doses) Chronic exposure chronic toxicity (solvents) (longer doses) Interaction of chemicals usually 1 exposure repeated doses repeated doses repeated doses. > 3mo: additive 2+3= 5, synergy 2+2= 20, potentiation 2+0=10, antagonism 4+6= 8 (bases of how we create antidote) How to : dose response: select test organism.