Diseases


A young girl in a pink shirt sneezes.
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Pollutants


A factory chimney lets out smoke into the sky.
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Radiation


A set of two X-ray films, one shows the front view of the chest and the other shows the side view.
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Social and Behavioral Factors


A young asian woman in sports wear runs in to the middle of an empty city road.
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Medicinal Drugs


Capsules spill out of an amber-colored medicine bottle that has fallen on its side.
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Psychoactive Drugs


A man smokes a cigarette.
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*The field of toxicology advances daily. Research on new substances begins with their effects on nonhuman species, which provides suggestive (though not conclusive) evidence. This activity is a primer; it is no substitute for careful consultation with a knowledgeable professional.