The door began to open in 2015.
The International Agency for Research on Cancer (IARC) of the World Health Organization (a powerful organization because it affects worldwide governmental standards for how the chemical is used) announced the results of its own independent, rather than industry-sponsored, laboratory tests.
Contradicting decades of Monsanto's claims, the IARC found glyphosate to be much more dangerous than previously reported and redefined it as a “probable” carcinogen.
The door opened even wider about a year later when California announced it would follow the IARC's lead. However, what California had to do first is to decide on the maximum daily amount of glyphosate exposure it would recommend as “safe,” also called the NSRL or “No Significant Risk Level.”