So it ends up that the US actually does have barium limits on toys introduced as part of the Feb 2009 overhaul (you might remember it caused a huge uproar on etsy due to testing requirements that put a lot of small crafts people out of business).
While the regulatory body hasn't been testing, the Canadian test results would put the toys above the current US limits as well, it's just not being enforced. I don't have the energy to retype it all and zrecommends says it best anyway:
That's likely to end up being a problem for M&D because while the testing requirements aren't in force, a company knowingly selling goods that are above the limits is breaking the law. And the line they've been giving retailers and concerned consumers is that it's only a problem in Canada and that they're "just" above the limit. Which kind of also sucks for US retailers because by extension they are also breaking the law.
Did I mention before how glad I am that we don't sell these? Sigh.