It is allowed on food crops in Canada and the European Union. The US in 2018 removed it from being barred on import products, which really opened up its use in industries targeting exports to the US. So the US rise in this chemical is almost certainly due to Canadian products.

Which is such an incredible shame for my country, Canada. It is shameful how often we trade risks to human health for minor production benefits. Canada and the US produce vastly more food than they consume, so the arguments about the necessity to push production efficiency at the cost of health is a non-starter.

The U.S. Environmental Protection Agency (EPA) has released for public comment its proposed decision to register the first food uses of the pesticide chlormequat chloride to provide farmers with an additional tool to help increase crop yield. Before registering these uses, EPA will need to establish tolerances in or on barley, oat, triticale, and wheat. https://www.epa.gov/pesticides/epa-proposes-register-new-use...

Exactly. Humans don't eat grain, right?