No person shall sell or possess any thallium or thallium Cornpound except federal, state, county, municipal officers or their deputies for use in their official duties in pest control; research or chemical laboratories in their respective fields; regularly licensed pest control operators for use in their own service work; properly registered ant, mole and rodent poisons containing thallium expressed as metallic not more than one percent; wholesalers or jobbers of pesticides for sale to the aforementioned persons; or for export.
Iowa Admin. Code r. 21-45.23