This kind of pollution is primarily widespread
- around old homes - flakes of previously used lead paints
- near busy roads - remnants of leaded gasoline
- around suburban homes, built near apple orchards - lead arsenate used to be a regular pesticide
In case you're determined to stick with your native earth, have it tested (look under "laboratories" in your phone book or pick up a home test kit which is less reliable but cheaper solution).
It's also good to know that
- peas and
The Boston Globe