Antifreeze; bittering required
Wis. Stat. § 100.383
in effect(1) Any engine coolant or antifreeze that is sold within this state and that contains more than 10 percent ethylene glycol, shall contain, as a bittering agent, denatonium benzoate in a concentration of not less than 30 parts per million nor more than 50 parts per million.
(2) A manufacturer of an engine coolant or antifreeze described in sub. (1) shall maintain a record of the trade name, scientific name, and active ingredients of any bittering agent used in the engine coolant or antifreeze, and shall make the record available to the public upon request.
(3) Notwithstanding s. 100.38, a manufacturer, processor, distributor, recycler, or seller of an engine coolant or antifreeze that is described in sub. (1) is not liable to any person for any personal injury, death, property damage, environmental damage, including damage to natural resources, or economic loss caused by the inclusion of denatonium benzoate in the engine coolant or antifreeze, if the denatonium benzoate is present in a concentration required in sub. (1).
(4) This section does not apply to the sale of a motor vehicle that contains engine coolant or antifreeze or to antifreeze sold in containers with a capacity of 55 gallons or more.
(5) A person who violates this section may be imprisoned in the county jail for not more than 90 days or fined not more than $1,500 or both.
Source: WI Statutes (Official Site)URL: https://docs.legis.wisconsin.gov/document/statutes/100.383Fetched: 10/7/2026