500.90 Regulation of polystyrene products preempted to department.—The regulation of the use or sale of polystyrene products by entities regulated under this chapter is preempted to the department. This preemption does not apply to local ordinances or provisions thereof enacted before January 1, 2016, and does not limit the authority of a local government to restrict the use of polystyrene by individuals on public property, temporary vendors on public property, or entities engaged in a contractual relationship with the local government for the provision of goods or services, unless such use is otherwise preempted by law.