No-observed-adverse-effect level

Okay, kiddo, let me try to explain what a no-observed-adverse-effect level is.

When we want to find out if something is safe for us, like a medicine or a chemical, we do different tests on them to see what happens when we are exposed to them. We want to make sure that they don't make us sick or give us any problems, right?

Now, when scientists do these tests, they often start with small doses and gradually increase them to see how our body reacts. A no-observed-adverse-effect level is the highest dose of a substance that can be given without causing any harmful effects in a group of test animals or people. It's basically the dose where scientists don't see any negative effects even if they look very carefully.

So, if a medication, for example, has been tested and the scientists found that a certain dose is safe with no side effects observed, then that becomes the no-observed-adverse-effect level. It's a kind of safety limit that tells us what the maximum amount of that substance we can take without it harming us.

Remember, scientists keep studying these substances to make sure they are safe for us to use. They may change the no-observed-adverse-effect level based on new research or findings. But for now, it's a good guide to help us use things safely.