Ecotoxicology Flashcards
Contaminant
“An agent that cause changes in the physical, chemical or biological properties of an environment or an organism.”
Types of Contaminants
- Inorganic
- Organic
- Microbial
- Radio Active
Inorganic Contaminant Examples
- Lead
- Arsenic Mercury
- Nitrogen Oxides
- Phosphorus
Organic Contaminant Examples
- Insecticides
- Pesticides
- PCBs
- Benzene
Microbial Contaminant Examples
- Viruses and harmful bacteria
Radio Active Contaminant Examples
- Uranium
- Plutonium
- Radon
Toxicity
When a contaminant effectively harms an organism it is toxic.
Types of Toxicity
1) Concentration
2) Type of organism it comes in contact with
3) Length of exposure
Toxicity Threshold
“The minimum concentration of a substance that produces a significant harmful effect in an organism.”
Lethal Dose
The amount of contaminant necessary in a single dose to cause the death of the organism.
LD50
The dose that causes death among 50% of individuals.
Bioaccumulation
“The process by which a contaminant from the environment or food supply accumulates in an organism.”
Bioconcentration
“A special case of bioaccumulation by which an organism accumulates a contaminant through direct contact with its environment, specifically a water environment, from sources other than food.”
Biomplification/Biomagnification
The phenomenon by which the concentration of a contaminant of a concentration in the tissues of living organisms tend to increase with each trophic level.
Biodegradation
The breaking down of organic matter into inorganic matter by microorganisms.
