Hi again,
basically anything but cotton, putting more pressure than a sock would, against your feet seem to cause a problem. Socks don’t cause a problem, but shoes do. Since to get white socks, you have to use chemicals to get them white, your skin doesn’t seem to have a problem with that. If you are able to wear colored cotton socks, you don’t seem to have a problem with the dyes coloring the socks.
Do you notice when you wear shoes that your feet sweat, noticeably? Because wearing socks, your sweat can easily evaporate. The excess sweat can act as a chemical vehicle and solvent extracting chemicals from the linings of your shoes. These dissolved, shoe chemicals can cause skin rashes (contact or allergic dermatitis). It would seem that this is going on because of the answer you gave about your skin being affected only where the sandal straps are.
From what I have read, they say to avoid cotton socks, as while they do absorb moisture, they hold the persperation against your skin. They say an acrylic/wool blend will suit you better.
Here’s the page where I got this info:
http://www.wethersfield.net/html/fhs/pis/sweatyft.html
At the bottom there is contact information to this doc’s office. Apparently he deals a lot with these kinds of foot issues. He says to give him a call if you have a severe case. But I think it is key in your case - you need a shoe that lets your foot breathe, and wicks the moisture away from your foot, without hitting anything in the shoe that has chemicals that will cause the moisture leaving your foot to react and cause a rash. You need a totally organic (un-chemicaled), breathable sock and shoe. I lump the sock in there because your sweat going through the sock may react with chemicals in the sock, that react with the shoe and being trapped, make it bakc to your skin and cause the reaction.
That is what one of the many dermatologists told me - he actually advised that I wear hemp birkenstocks.
I thought that might be a problem, as I worked in the Pentagon at the time.
The security dogs already hate me, because of the constant smell of cordite on my clothes.
Hemp shoes or barefoot - I pick barefoot. Then I don’t have some police dog trying to chew me foot off. LOL.