Just did a bit of online research into the safety of ink on skin. The only problem that I found could be with people having an allergy to it. It seems to be harmless. My personal belief is that more harm is done by using a lot of baby shampoos etc (especially Johnson & Johnson products). I found a lot of information warning parents not to use soaps and detergents on very young babies skins. Anyhow, I'm now fairly confident that a "one off" contact with ink would be ok and no more harmful than any other printing medium. I did an occupational health and safety subject at uni when I was studying Fine Art and ink was never covered... that's not to say it's not hazardous to small babies... but a lot of mediums were mentioned... you wouldn't believe how toxic some oil paints are! Actually! It's just occured to me that if the brand Crayola make an ink pad it would almost definately be the safest product to use! Crayola is a fantastic brand and always washable in water.