Earth Day has come and gone, but for some Hollywood types, the lure of green continues to be enticing. For example, “Healthy Child Healthy World,” a new book from the Los Angeles-based advocacy group of the same name, written by Christopher Gavigan, the group’s chief executive — with an introduction by Meryl Streep and advice from the likes of Gwyneth Paltrow, Sheryl Crow and Tom Hanks — urges parents to forgo chlorine bleach and ammonia for hydrogen peroxide and h...