California Code, Business and Professions Code - BPC § 22203

No bag made of polyethylene plastic material thinner than 0.001 inch which is large enough to fit over a child's head shall be used, after the effective date of this section, by any retail store as a container for products, other than for food products weighing not more than five pounds, delivered to purchasers, or by any other retail business establishment to package articles delivered to customers, if any cartoon, picture, or caricature is on such bag which cartoon, picture, or caricature will, or will have a tendency to, facilitate or encourage the use of such bag as a toy by children under 12 years of age.

This section does not prohibit legitimate advertising which does not facilitate or encourage the use of such bag as a toy.