My Boyfriend Probably Has Trench Foot From Working In Standing

My boyfriend probably has trench foot from working in standing ( usually DIRTY unsanitary ) water for several hours at a time each day. He installs swimming pools and vinyl liners for a living. He sometimes wears rubber boots, but also sandals or his sneakers a lot of the time. He's been doing this quite often the past 3 months. His feet are white, stay wrinkled even when dry, it's painful to just have feet basically. I just saw the bottoms of his feet and they look dead