Chapter 10 Flashcards
Environmental health;
Assesses environmental factors that influence human health and quality of life (includes human caused and natural factors)
Toxicology
The study of the effects of poisonous substances on humans and other organisms
Toxicity
The degree of harm a chemical can inflict
Toxicant
Any toxic substance (poison)
Environmental toxicology
Deals with toxic substances that come from or are discharged into the environment
Toxins
Toxic chemicals made in tissues of living organisms (plants produce chemicals to ward off being eaten)
Carcinogens
Cause Cancer
Mutagents
Cause DNA mutations
Teratogens
Cause birth defects in embryos
Neurotoxins
Affect the nervous system (lead mercury)
Allergens
Overactivate the immune system
Pathway inhibitors
interrupt biochemical processes
Endocrine Disruptors:
affect the endocrine (hormone) system
Acute Exposure:
High Exposure to a hazard for short periods of time.
Easy to recognize
Stem from discrete events: ingestion, oil spills nuclear accident
Chronic Exposure
Low exposure for a long time
-More common, harder to ditect
affects organs gradually: lung cancer liver damage
Bioaccumulation
Fat-soluble toxicants build up in animal tissues, can transfer toxins to other through food chain
Biomagnification
Toxicant concentrations are magnified through trophic levels - near extinction of peregrine falcons and bald eagles
Dose-response analysis
Response of test animals to different doses
Dose:
Amount of substance the test animal receives
Response:
the type or magnitude of negative effects
Dose response Curve
A curve that plots the response of test animals to different levels of a toxicant
LD50/ED50
(Lethal dose/effective dose) The amount of toxicant required to kill/affect 50% of the subjects
Threshold dose
The level where a response occurs
Risk Assessment
The quantitative measurement of risk
