I don’t know if it’s universal but here every kid is tested for lead. When we did that, our pediatrician warned not to grow vegetables within 10’ of the house.

For any house in the us built before mid 1970s you most likely had lead exterior paint Which would contaminate the soil. However they weren’t concerned about it still being concentrated enough to harm people directly, only if you ate contaminated vegetables

The lead will never go away, but it does disperse, mix in, get covered over time