How long is sufficient? How large of a test group is sufficient?

In the "absolute" sense, there is no known drug that is safe. That is extremist thinking that only serves to muddy the waters of the actual debate, which should be: "how safe is safe enough?"

> we are not 100% sure it is safe

Note that "100% sure" does not mean "100%" safe. So how much safety do you need a 100% assurance for? How do you quantify the safety?

> that sounds really scary

How does this not just describe life in general? And how does that help policymaking? I don't think our species would have made it to the agricultural revolution if that was the overriding force for anything.

> it will not convince anyone who was not already convinced

This also strikes me as a poor consideration for any policymaker, as they likely know that at the onset to any such policymaking. This adds nothing new or interesting to the debate.