There was a recent study which found child blood lead levels were higher in areas with high gun ownership after controlling for socioeconomics.

https://www.hsph.harvard.edu/news/features/higher-rates-of-f...

I don’t know how much their exposure was but I’d estimate they are closer to the skinny edge of the bell curve.

Maybe they had especially bad practices, like never washed their hands, exclusively eats finger food after picking through their spent bullets and licks their fingers?

Lead dust settles everywhere, gets into your lungs, especially if it's an indoor range.