Allergic to Eichler?

Greetings!

Yesterday my husband and I had our offer accepted on an early Eichler, built in 1950. I am thrilled. The house has many original touches, including wood panels that look like they're plywood and a sort of woven fiber on the walls under about a chair rail height. (Yes, I'll be buying some of the books recommended here... I'm sure there are names for all of this.)

Problem: my husband is highly allergic to something in the house. I don't react at all, and we don't think it's mold. While he's willing to keep the paneling (which at first he found too dark and we'd compromised on keeping an accent wall, but with more time he thinks is not too dark) it seems like that's what he's reacting to.

Unquestionably, my husband's ability to breathe trumps keeping the original aesthetic. We would offer the panels to other Eichler owners and will not let contractors rip them out.

Yet I wonder if anyone else has run into this sort of problem? We're not even sure it's the paneling, and I wonder about the fiber wall covering in particular. Or perhaps we need to do something completely different, maybe sealing the ceiling. Any experience or thoughts on this would be really helpful.

Thanks!