There is concern about elevated levels of soil lead content, but in general the concern should be more about lead contamination from external lead on unwashed produce than from actual uptake by the plant itself. Care should be taken to avoid making direct contact with the soil (ingesting or inhaling) and all harvested crops should be thoroughly washed to removed any contaminated soil particles (deposited through splashing, blowing or direct contact).
For a more detailed discussion: http://www.extension.umn.edu/garden/yard-garden/soils/lead-in-home-garden/
for testing, contact A&L Great Lakes Lab, Fort Wayne IN. You can check their website for services etc.
