If you walk into the lab and your nose starts to crinkle, there are many possible suspects. Bitesize Bio's Nick Oswald rounds up 10 likely culprits, and coming in at number seven is fly food. "What do they put in that stuff? Year-old bananas?" he asks. But there are worse smells that abound. Oswald calls N-butanol "nasty, sickly stuff" and adds that cadaverine "smells like decomposition in a bottle." But the top spot honor goes to beta-mercaptoethanol.