In environmental health, the term toxin refers to a toxic substance that _______________.
is naturally produced by a plant or animal
occurs in the occupational setting
results from human activity
a man-made product introduced into the environment due to human activity
In toxicity testing in rodents, the LD50 is a dose that is _______________.
acutely fatal to 50 percent of test animals
fatal to 50 percent of test animals within a 90-day period
fatal to 50 percent of test animals after lifetime bioaccumulation
Which of the following is not characteristic of a health impact assessment?
It evaluates a site or activity as it is, rather than looking forward in time
It includes social and economic factors in the assessment