When growing sprouts, you should always look out for signs of mould or bacteria growth.
If you observie small, odorless, white hairs growing from your sprout roots, these are cilia hairs - which are totally harmless, but are a sign that the roots are dehydrated. Soaking the sprouts in cool water for 15 minutes should get rid of them
If you observe a dark growth with an unpleasant odor and slimy texture, this is likely mould. If your sprouts are mouldy, dispose of them and start a new batch.