Here is some information from the UPMC website.
To promote poison prevention and the poison center, the iconic symbol Mr. Yuk™ was created by the Pittsburgh Poison Center and was the first recognized poison prevention/poison center awareness symbol in the U.S. Since then, Mr. Yuk has been used to educate children and adults in the U.S. and internationally about poison prevention and to promote poison center awareness.
Mr. Yuk has raised the awareness that poison centers are available 24 hours-a-day, every day of the year to assist in the management of poisoning emergencies and to provide poison information. Every Mr. Yuk sticker contains the name of the nearest poison center and the national toll-free “Poison Help” telephone number: 1-800-222-1222. Regardless of your location in the U.S. or its territories, dialing that number will direct your call to the nearest regional poison center.
Vist the Mr. Yuk online store.
To request a free sheet of Mr. Yuk stickers, please send a self-addressed stamped business size envelope to:
Pittsburgh Poison Center
200 Lothrop Street
Pittsburgh, PA 15213