Science is descriptive, not prescriptive. It describes how the world is. Regulations are prescriptive decisions taken by people, based on a variety of reasons.

Scientific knowledge can be one such reason. But there are a lot of other reasons that can motivate a regulation. Two identical regulations can have different reasons.

Can you demonstrate these ancient regulations are based on (accurate) scientific knowledge?

There are probably many things in the Bible that would be called science, that doesn't mean anything. Just because the Bible gets something right (probably by copying it from some other source) doesn't mean the entire Bible is right.