Yellowish Stains on Whites/Light-Colored Shirts - Hoping it's not Mold???

[TheSkaFish]

Hello all,

Recently while sorting my laundry, I noticed that most of my white shirts (and one very light gray) appeared to have small, yellowish-brown "goldenrod"-colored stains on them. I have had all of these shirts for several years, and the stains do not appear on newer whites, nor do they appear on darker clothes of any age. Most of these stains are on the back of the shirts. They all appear on the inside of the shirts, which contacts the skin.
The stains haven't changed or grown over the years, and they haven't shown any signs of deterioration in the fabric in those areas. The stains also don't seem to have any odor or texture (fuzz, raised structures, etc.). They don't itch or cause any irritation. If I had to guess, they look closest to old sweat or old blood stains that have faded to yellow over time.

Still, because I don't know what the stain is, I became worried about mold, even though it doesn't match any mold color I've ever seen and doesn't seem to have other signs. While the shirts are low in monetary value they are high in sentimental value (and also out of print) and I'd hate to have to throw them out.

Has anyone had these stains themselves, know what they might be, or how I may wash them out? Am I worrying about mold for nothing?
Here are some pictures. I've labeled the ones I think are just sweat/blood and probably nothing, but still not sure:

http://imgur.com/a/KzMCO

Any help would be appreciated! Thanks.

 

[MikeDT]

Benzoil peroxide possibly.

http://www.apparelsearch.com/educat...emoval/how_identify_stains_prevent_stains.htm

"Odd colored or rusty looking stains on collars, sheets and pillow cases, bedspreads, towels, or wash cloths: These stains are often caused by the benzoil peroxide used in cosmetic products (including acne medicine). This chemical acts as a bleach, is very insoluble and hard to rinse off the body. It can permanently change colors of some dyes. The damage cannot be remedied, So it should be prevented. When products containing this chemical must be used, white collars and household textiles may be a good choice."

 

[TheSkaFish]

Hmmm. I don't know, I haven't used benzoil peroxide in years, since well before I got any of those shirts. I doubt it would be that.

Thank you for replying, though. Even if it were something like that, it's not on the front of the shirt and much less noticeable on the outside. I'd just be glad it's not mold, anyway.

Do you think it's possible that it might just be salt deposits from old sweat stains, or old, faded blood stains? I do sweat a lot, and these are all short-sleeve, summer shirts. I also get back acne sometimes, which can bleed a little.

 

[MikeDT]

Didn't think it was mold, looks more like some sort of chemical stain. I originally thought it might be ferric chloride, because it looks very much like a shirt I ruined once while etching printed circuit boards.

Any household chemicals you keep around the place might have got near the laundry, things like polish, disinfectant, cosmetics, medicine, etc.

Have you tried laundering them at all? Don't know exactly what to suggest, try cold first, then warm. If they're white 100% cotton, try some bleach.

 

[TheSkaFish]

Well, I'm feeling comfortable now that these stains aren't mold, and I've taken down my pictures since we don't need them anymore.

Thank you for taking the time to help, Mike. I'm quite relieved to not have to throw my shirts out after all! Cheers.