Do pesticides like those used in anti-flea spot-on products for pets bioaccumulate in the human body?

Question

For example, if you pet a dog that is treated monthly with Frontline, and invariably as a result thereof, your hand gets some of the pesticide on it, wherein the chemical absorbs into your bloodstream and cycles through your body... Does it quickly get flushed out if in small quantities like what you'd get from petting the animal, or does the pesticide settle in your organs and brains for YEARS and potentially cause you detrimental health problems?

Answer 1

Some of it will most likely make its way into your body, but it is eliminated relatively quickly and won't build up and cause problems.  All of the reputable products have been tested for safety for human contact, so you as long as you don't pour the stuff all over you, you should be just fine :)