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Biomagnification= This is when the concentration of Toxicants increases or becomes "magnified" as the food chain progresses.

DDT is an example of a substance that biomagnifies; this is seen when birds get sufficient amounts of DDT from eating fish that have DDT from other organisms in the environment.

Biomagnification is essentially when an organism has a toxicant at a low trophic level, and then that organism "passes on" that toxicant by being ate by predators; which causes the TOXICANT concentration to INCREASE substantially as it progresses through the food chain.

Bioaccumaltion= The gradual build up of a chemical in an organism over time.

The Ames Test= Test made to screen suspected toxins.

Case Study= Process used for observing and analyzing INDIVIDUAL patients that are affected by poision.

Problems of Case Study approach: they dont help us infer the effects of rare hazards, or the effects from newly manufactured compounds.

Epidemiological Studies= Studies involving comparing a group of people that has been affected to a hazard to a group that HAS NOT been affected by that hazard.

*Toxicoligists give lab animals much higher doses of a substance than a human would recieve from nature because...

-To ensure that response is great enough to measure

-And so the differences between the low doses and the highn doses can be seen clearly.

*Sometimes Toxicoligists see dose-response curves producing U-shaped or J-shaped curves, this is likely to happen because of...

-Endocrine Disruptors cause changes to the dose-response curve, resulting in changes of the shape of the curve.