So, I'd agree that there are lead levels too low to be worth worrying about. But I recall a clever study a while back where a researcher noticed that children found to be in the top decile of lead exposure got lead abatement for their homes or apartments by the city. The researchers compared them to the previous second decile (now first decile) and found a pretty significant effect size on life outcomes. This was done on poor people in city centers so the lead levels were high compared to, say, suburbanites but there are lead levels many kids in the US are exposed to that are actually a big deal.

I taught my kids to look both ways. Now what do I do?

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