Citrus fruit inspectors are authorized:
(1) To inspect citrus fruit, except grapefruit, for arsenic content at any packinghouse, canning plant, concentrating plant, or other place where citrus fruit, except grapefruit, is being received or prepared for sale or transportation, and
(2) To enforce the provisions of these arsenic laws under the direction and supervision of the Department of Agriculture in accordance with the law and rules and regulations prescribed by the said Department of Agriculture.