Chpt 4.1-4.6 (Risk) Flashcards
Hazard Identification
Process of determining if a chemical is causally linked to health effects.
Dose response assessment
Process of characterizing the relationship between foes of agent and how it effects health
Risk Assesment Steps
- Hazard Identification
- Dose Response/ Exposure assessment
- Risk Characterization
- Risk Management
Exposure Assesment
Determine how many people were exposed, how much they were exposed to and for how long. Consider things like age, health, health related habits and pregnancy
Risk Characterization
Characterize the risk using exposure, dose, and hazard level to estimate how much of a risk the contaminate poses.
Three Ways Toxins Can Enter The Body
Ingestion
Inhalation
Contact
Once in the body toxins can be
Absorbed
Distributed
Stored
Excreted
Hepatoxins
Toxins that attack the liver
CCl4
CHCl3
C2HCl3
Ex: Pestasides
Nephrotoxins
Attack the kidneys
Ex: Mercury, lead.
Acute Toxicity
Effects that are caused within a shot period of time after a single exposure to the chemical
Chronic Toxicity
Effects that occur after prolonged exposure to a chemical
Mutagens
Cause changes in DNA
Can result in cancer, reproductive failure, or birth defects
Carcinogen
Causes cancer
Two stages:
Initiation - alters genetic material
Promotion - cells divide without limit
One Hit Hypothesis
The theory that one small dose of a carcinogen can cause cancer, meaning there is no dose for which the risk is zero
Animal testing requirements
At least 2 species of rodents used
At least 50 males and 50 females of each species used
At least two doses must be given plus a control
