Uh...in Calif they sue the landlord wih the help of the State. Lead paint removal is a huge scam here and elseware as depicted on This Old House many times. My bet is this will go the way of RADON gas scare of a few years ago. Asbestos removal is another scam that causes more harm than good in many cases.
I think the reseach so be directed at how deliquents accumulate lead in their systems.