California’s Office of Environmental Health Hazard Assessment (OEHHA) has approved two Maximum Allowable Dose Levels (MADLs) for n-Hexane under Proposition 65. The two MADLs, which will be implemented starting July 1, were 20,000 and 28,000 micrograms per day for inhalation and oral exposures respectively.
Proposition 65, the Safe Drinking Water and Toxic Enforcement Act of 1986 that prohibits businesses with more than 10 employees to knowingly and intentionally expose any individual to a listed substance without first giving a “clear and reasonable warning.” However, the law does not require any warning if the exposures are below a “safe harbor” level or MADL for chemicals causing reproductive toxicity.
Prop 65 is also considered a consumer “right-to-know law” because it informs or warns consumers if certain products or packaging contain hazardous chemicals.
N-Hexane is a solvent component, degreaser, and low-temperature thermometer filling. In December 2017, the chemical was listed as a reproductive toxicant under Prop 65.
The MADLs of 28,000 and 20,000 micrograms per day for oral exposure and inhalation exposure respectively were proposed as the safe harbor values in September 2018.
OEHHA opened the proposed MADL for public comments until November 19, 2018.