I'm in Colorado not that it's really relevant here... I've worked for Kroger for almost a year and I've been offered a full time position. Will there be medical screening for health insurance purposes? If so, will there be drug testing? I regularly smoke weed (off the clock obviously) and am worried that accepting full time could end up getting me fired.
Read your union contract... under mine they don't test you after hiring unless you have an accident, or you become a comanager (because you get "fired" and rehired). Given the state you live in, things may be very different and I would report your findings back here though :D