I don't know where the fruit and veg that I buy is grown and I don't trust the food industry at all.How do you know the fruit and veg you buy in shops has not been grown near roads? I don't. It doesn't say exactly where it's grown.
Also one of the posts in Teuchter link says imo correctly that a lot of fruit and veg is transported on roads in lorries. So is well exposed to road pollution.
However choosing not to pick fruit grown on a busy road or not buying fruit that's been displayed outside are some of the only thing that are within my power to do. So I do them. Like choosing not to shop with Amazon, for example.
I don't think a handful of one line sentences or opinions on a money saving forum proves a whole lot.