Well, depends on which steroids you are interrested in and of how low the traces are! Basically I think you should use Immunoassays for the most common steroids.
Via Simple UV spectroscopy is it possible to know the presence of steroid? the absoprtion maxima would be in between 235 to 245. is it a reliable method. i just want to know the presence or absence of any steroid.
I have used radio immunoassay to test for corticosterone and testosterone in commercial samples of some Ayurvedic medicines and some stimulants such Gutka which contain tobacco and claim for sex stimulation. However the material has to be extracted as the ingredients interfere withe assay