In reaction to the recent lead-painted-toy recalls, no doubt some laissez-faire non-parents shrugged it off — when pretty much everything is tainted with toxins, what’s a little lead in paint? Except that, well, it was more than just a little lead. Some of the toys recalled by Mattel this summer contained 180 times the legally allowable level of the heavy metal, while some kids’ jewelry sold by the Oriental Trading Co. was, stunningly, 96 percent lead. Playing with such things for one to six months could give a child “substantial, severe lead poisoning,” says pediatrician John Rosen, who has treated 30,000 lead-sickened children. So keep your kids away from heavy metal: Metallica not included.