>>11594167The inhabitants of the Biosphere 2 project were found to have DDT and other banned chemicals in their blood. Initially it was thought somehow the habitat had been contaminated with these chemicals somehow but it turned out they had been absorbed by their bodies when they were common in their environment decades earlier and were being released into their blood as they burnt through fat stores they'd put on over the years.
It's possible that the large dose of the drug you took has been stored in some of your tissue and can leak out into your bloodstream especially if you're undergoing weight loss that results in some of that tissue being broken down for energy.