|MadSci Network: Medicine|
Matthew, One could potentially get sick from anything that somebody else has handled--as bacteria are on everything. Fortunately, most bacteria usually tend to die quickly if there is not a food or water supply, so dollar bills aren't the best place for them long term. Some viruses (the common cold is a great example) can last longer before dying. Overall, you'll be much more likely to get sick from shaking a hand, hugging, kissing, etc, since humans are a much better nutritional supply for germs. As far as the drugs on the bills, I would guess that that the levels left over after somebody's finished are not significant enough to harm you. If you actually see a strange substance on a bill, then I would recommend avoiding it. Michael Crawford
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