Scrap Proposition 65, California’s Unscientific Chemical Safety Law

California may soon list glyphosate, the active ingredient used to make Roundup weed killer, as a carcinogen under the state’s so-called “right-to-know” law, originally passed by voters in 1986 as Proposition 65. Its maker, Monsanto, says it will appeal a recent court ruling that would allow the state to proceed, but they may not be able to stop it, even though the state’s claim isn’t supported by much science.

The issue took hold in 2015 when California’s Environmental Protection Agency’s Office of Environmental Health Hazard Assessment (OEHHA) published a decision to list glyphosate and several other pesticides – tetrachlorvinphos, parathion, and malathion – as “known to the state to cause cancer.” The state makes such classifications under its Proposition 65 law, which requires all products that include such chemicals bear warning labels. 

Such labeling might seem innocuous, but such listings can actually be quite misleading and result in adverse public health effects. 

For example, the state has also listed the chemical Bisphenol A, which is used in resins that line food cans. BPA acts as a barrier to prevent development of contamination from rust and potentially deadly pathogens. There is no compelling evidence that BPA poses any health risks at current exposure from food packaging and in fact many scientific bodies around the world have deemed such exposures as safe. There is plenty evidence that BPA provides public health benefits by reducing risks of food borne illnesses. So a Proposition 65 listing is not only misleading, it may deter BPA use and encourage companies to switch to less well tested, inferior alternatives. And if these inferior products fail, more people may suffer from real, dangerous foodborne illnesses.

The same goes for mislabeling of pesticides as “carcinogens.” These chemicals are used to help produce a safe and affordable food supply. If minute traces end up on vegetables, it doesn’t have public health consequences, but labeling will continue to generate fear about conventional fruits and veggies. As a result, people may consume less of such healthy produce and/or end up spending more money for “organic” produce, which really isn’t any healthier. This is a sad situation because a diet filled with healthy fruits and veggies is the best defense against cancer!

Moreover, the lack of science that the state is using to dub these chemicals as carcinogens is appalling. Consider the fact that glyphosate is used to make agriculture more productive and affordable. In addition, it helps reduce the need to till the soil, which reduces soil erosion and thereby runoff and water pollution. These benefits can be lost if farmers abandon it because of negative publicity. 

The main reason the state wants to list “glyphosate” is because in 2015 the International Agency for Research on Cancer (IARC) placed it on the category of “probably carcinogen.” But this decision was driven more by irrational anti-Monsanto politics than science. In any case, IARC classifications are largely useless because they simply focus on hazard, rather than risk. Hazard classification doesn’t consider exposure, which is key. Consider the fact that water is hazardous because of drowning risks, but when exposure is limited to a cup of water, it’s not risky. Because IARC doesn’t consider exposure, its classifications are not only meaningless, some are just plain dumb. For example, other IARC “probable human carcinogens” include “being a hair dresser” and eating red meat, but no one is rushing out to ban those.

The real problem isn’t these chemicals – it’s dumb classification systems and the misleading impact of “right to know” laws. If policymakers really want to help consumers, they need to ignore IARC and scrap California’s Proposition 65 law.