Comment by samdoesnothing

I agree with this. When Michael Huemer talks about political knowledge he lists several requirements:

1. Simple. For example, “Demand curves slope downward.” The more complicated a theory is, the more ways there are for it to go wrong.

2. Accepted by experts. For example, there is a broad consensus in economics that protectionism is undesirable. If a theory is well-justified, then the great majority of reasonable and intelligent people will usually come to accept the theory, once they understand the arguments for it.

3. Non-ideological. Theories that have an ideological flavor and that call forth strong emotions tend to be pseudo-knowledge–for example, the theory that behavioral differences between men and women are entirely due to socialization. Reality is unlikely to conform to ideology.

4. Weak. For instance, we do not know that free markets are always perfectly efficient. We can say only that free markets are usually approximately efficient.

5. Specific and concrete. We can be much more confident in a concrete claim such as “Ted Bundy’s murders were wrong” than in an abstract theory such as “It is always wrong to initiate violence against another person.”

6. Supported by appropriate evidence. For example, the claim “violent entertainment increases violent crime” cannot be known without empirical evidence. In this case, a study based on a large, random sample would be appropriate, rather than, say, a few anecdotes.

7. Undefeated by counter-evidence. If there is a large quantity of evidence against P, or if one does not know whether there is such counter-evidence, then one does not know that P. For example, if one has read several studies supporting gun control while having read none of the literature on the other side, then one cannot claim to know whether gun control is desirable.

The claim "Leaded gasoline should be banned" reasonably fits most of these requirements, thus it's probably a relatively safe intervention with upside.