Their experience is that the general commercial products are the safest to use - all the organic small scale farmed stuff sold to the general public is highly hit and miss, sometimes they're less contaminated but quite often it's literally off the charts e.g. hundredfold exceeding the limits allowed for commercial products, or have all kinds of dangerous bacteria (indicating e.g. fecal contamination) that they've never seen in samples of the mass produced food. Also, things their relatives have grown not for sale but for themselves with the purest intent have sometimes been contaminated - e.g. some parasites in their pork.
TL;DR - home-grown stuff can be expected to be less healthy and more dangerous than the industrial farming processes in well regulated first world countries. Often more tasty, though.