There are some counter examples, like Thalidomide, and in a field where regulators (used to) trust each other and just accept what other countries' regulators s

There are some counter examples, like Thalidomide, and in a field where regulators (used to) trust each other and just accept what other countries' regulators said, aviation, the 737 Max (which nobody tested properly because the FAA didn't do their job and let Boeing self-certify, meanwhile EASA and other air regulators accepted the FAA's stamp of approval, not knowing it wasn't worth anything). Also, different regulators have different thresholds - for instance many things that pass in the US food-wise wouldn't in the EU - be it chlorinated chickens, "false"/misleading labels, etc., and vice versa in some hilarious cases like Kinder Surprise (banned in the US because non-edibles inside food aren't acceptable to the FDA, meanwhile in the EU people just... teach their kids that you open it to get the toy, and eat the rest).