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Urushiol Oil is Potent
*Only 1 nanogram (billionth of a gram) needed to cause rash
*Average is 100 nanograms for most people
*1/4 ounce of urushiol is all that is needed to cause a rash in every person on earth
*500 people could itch from the amount covering the head of a pin
*Specimens of urushiol several centuries old have found to cause dermatitis in sensitive people.
*1 to 5 years is normal for urushiol oil to stay active on any surface including dead plants
*Derived from urushi, Japanese name for lacquer