65 ILCS 5/11-17-5

The public health board may initiate and maintain activities for the promotion of maternal child health, industrial hygiene, mental health, sanitary housing, public health education, and shall have the right to inspect and regulate all food and milk products kept or offered for sale within the jurisdiction of the board; may prevent and suppress contagious diseases, and may initiate and maintain programs or activities which from time to time may become necessary or proper for the promotion of public health within the jurisdiction of the board.