Avocado hand isn't the only risk involved with everyone's fave fatty fruit. A recent FDA report found that 17% of avocado skins tested positive for listeria. NBD if you aren’t eating the skin, right? FDA And when it comes to "hard produce" like avocados, you should be scrubbing with a produce brush. Washing your avocados is definitely worth it. This isn't something you want to mess around with...even in the name of avocado toast. Listeria comes with all kinds of nasty symptoms including headaches, convulsions, fever and muscle aches.