Experts in substance abuse are warning parents about a product that may soon be for sale: powdered alcohol, says Michele Caliva, RN, administrative director of the Upstate New York Poison Center at Upstate Medical University. One packet of what is called "Palcohol,"mixed with 5 ounces of liquid, creates a drink as strong as a shot of vodka. The packets resemble Capri Sun drinks and come in flavors, which Caliva fears would be attractive to children and easy to carry, conceal and abuse. The federal government has approved its sale, but a bill in Congress would ban it because of its potential danger to children.