Tomato leaves question
I planted 8 tomato plants in May and they are doing well--very tall with lots of blooms and some tomatoes forming. They look quite healthy, but several of the plants (different varieties) have leaves that have turned white in the middle and those leaves eventually wither and die. Pictures 1 and 3 below are the front side of the leaves and picture 2 is the back side of the leaf. When looking at the backs of the leaves with the naked eye, I didn't see any aphids or other bugs, but in picture 2 it looks like maybe the camera captured some minute critters. Anyway, what do you think is causing this and how to I correct the problem. Thanks very much for your help.
This looks like a symptom of herbicide injury. https://extension.umd.edu/hgic/herbicide-damage-vegetables
You could prune out the symptomatic foliage or leave it as is. We cannot say how it will affect additional growth and fruiting.