People tend to recommend washing (even just with water) fruits/vegetables before eating them for health reasons.
Do we have evidence that washing fruits/vegetables with water reduce potential health risks?
I expect it depends on how dirty the food is to begin with, and on what type of dirt (just as the answer to this other question depends on how dirty the floor is), and also on whether the food is subsequently cooked.
However, the FDA site says that that's not effective for sprouts:
One problem (i.e. the reason why washing doesn't always work) is that pathogens can sometimes get inside the produce: for example, see item 3 of this web page:
The same page lists "What is the efficacy of produce washing at home? (Does water remove pathogens from product?)" as a low-priority research area for them.
Page 43 of this 2008 WHO document (on which that previously-mentioned Canadian page was based) says various things including,
This quote from the same WHO document implies that washing is more effective for fresh-harvested produce (e.g. from your garden), and less so for older produce:
A lot of data is about food safety protocols on farms (how should they manage their manure/fertilizer, for example), and in the commercial processing which follows, before it's delivered to the consumer.