The first time I noticed it, I was baffled—a strange, almost neon-orange blotch on my favorite grey hand towel.

It didn’t look like a normal stain; it glowed faintly, as if someone had highlighted it with a marker. I assumed it was rust from the towel bar or some forgotten spill. After a vigorous wash with extra detergent, I was sure it would disappear. It didn’t.

Weeks later, more towels suffered the same fate. My bathroom began to resemble a crime scene involving pumpkin spice. If you’ve seen towels, pillowcases, or even shirts develop stubborn orange patches, you’re not imagining things. The culprits are surprisingly common.

1. Benzoyl Peroxide: The Primary Offender

The biggest cause is benzoyl peroxide, a popular acne treatment ingredient. Instead of staining in the usual sense, it bleaches the fabric’s dye, leaving behind an orange or yellowish mark. On darker towels, the contrast is even harsher.

Once the color is stripped from the fibers, there’s no way to restore it. My realization came when I noticed the marks matched where my face and hands touched the towel at night. Even short contact adds up over time.

2. Rust and Iron in Water

Not all orange marks are chemical burns. Iron-rich water, particularly from wells, can leave rusty freckles on fabric. I learned this visiting a friend in the countryside—two washes later, my white towel was covered in tiny orange flecks.

The fix wasn’t more detergent, but a rust-removing laundry additive, which binds to iron before it sets into fabric.

3. Hair Products and Self-Tanners

Certain shampoos, conditioners, and self-tanners also transfer pigment to towels. Even when “dry,” some products leave behind enough residue to stain. I once wondered about faint orange smudges on my hair towels—until I realized my “warmth-enhancing” shampoo carried pigment strong enough to cause them.