PHAR 303 Lecture Notes - Lecture 21: Personal Protective Equipment, Shortness Of Breath, Causative

• School: McGill University
• Department: Pharmacology and Therapeutics
• Course: PHAR 303
• Professor: Bernard Robaire

Document Summary

How chemicals in the environment affect individuals, populations, communities, ecosystems, and their potential impacts on. Depend on: physical and chemical properties of the chemical. Air: winds, turbulence, temperature, vertical mixing: diffusion in air ~100 times faster than in water, chemicals can be trapped closer to the earth"s surface. Water: diffusion, dispersion, bulk flow (rivers, underground channels: diffusion in water is much faster than in soil. Soil: composition (sand, silt, clay, organic matter), water/air filled pores: diffusion through water/air voids between soil particles, partition between solid and fluid fractions (like chromatography, presence of sediment-dwelling organisms (bacteria, worms) We can measure and predict how a chemical will partition between environmental compartments: air (atmosphere, water (hydrosphere) Chemodynamics: study of chemical behaviour in environment: release, transport, distribution within and between compartments, metabolism, degradation, storage, excretion, concentration. Major factors that influence the impact of environmental chemicals. It takes 4 half-lives for a compound to be removed from the environment.