Glyphosate Listed Effective July 7, 2017, as Known to the State of California to Cause Cancer

On March 28, 2017, the Office of Environmental Health Hazard Assessment (OEHHA) posted a Notice on its website[1] that glyphosate (CAS No. 1071-83-6) would be added to the list of chemicals known to the state to cause cancer for purposes of Proposition 65[2] with a delayed effective date due to the pending case Monsanto v OEHHA.[3]  

Monsanto’s challenge was unsuccessful in the trial court.  Although the case has been appealed, no stay of the listing has been granted. Therefore, glyphosate is being added to the Proposition 65 list on July 7, 2017.

In summary, glyphosate is listed under Proposition 65 effective July 7, 2017 as known to the state to cause cancer, as follows:





    Listing Mechanism*






*Listing mechanism:  LC – “Labor Code” mechanism (Health and Safety Code section 25249.8(a) and Title 27 Cal. Code of Regs. section 25904)

** The International Agency for Research on Cancer (IARC) indicates the following chemicals are “also relevant: 38641-94-0 (glyphosate-isopropylamine salt) 40465-66-5 (monoammonium salt) 69254-40-6 (diammonium salt) 34494-03-6 (glyphosate-sodium) 81591-81-3 (glyphosate-trimesium)” (IARC, 2015b), because these salts dissociate to free glyphosate.

Link to Public Comments


Footnotes and References

[1] The Notice was published in the California Notice Register on April 7, 2017.

[2] The Safe Drinking Water and Toxic Enforcement Act of 1986, Health and Safety Code section 25249.5 et seq.

[3]Monsanto et al v OEHHA et al., Fifth District Court of Appeal, case number F075362.