If Your White Shirts Have Yellow Collar Stains in the Summer, Here’s the Culprit (And How to Fix It)

Ah, the joys of summer laundry. For a few months of the year, we have the pleasure of tackling some of the toughest stains out there, from ketchup and mustard to grass and sweat. But there’s another summer stain you may not be as familiar with. Ever do a load of laundry after a day outside and notice a weird, yellow ring on your shirt collar that you just can’t seem to get out? It’s probably related to your sunscreen!

Here’s why sunscreen stains can be particularly stubborn. Sunblock commonly contains an ingredient called avobenzone, an oil-soluble compound that helps your sunscreen absorb the full-spectrum of UVA rays. (And that’s a good thing, because UVA rays are the type most commonly associated with skin cancer.)

Avobenzone alone can discolor your clothes, like any skincare product might. But the real problem happens when the ingredient comes into contact with iron, which is present in most tap water (especially hard water). Basically, when avobenzone meets iron, a chemical reaction takes place that creates reddish rust stains that can be really difficult to remove.

So, rather than employing your go-to oil-fighting trick like you would for standard lotion, you’ll need a more targeted approach. Cleaning expert Jolie Kerr suggests treating with a rust-specific stain remover, such as Carbona Stain Devils #9 Rust and Perspiration. (Keep in mind Carbona Stain Devils isn’t a pre-treatment; you’ll need to treat and fully rinse before laundering.) You can also run to the hardware store and grab a rust remover like Whink, which Kerr says can work on hard surfaces as well as fabric. 

Don’t have any rust-specific products on hand and want to remove the stain, like, now? No matter what you do, avoid bleach, which can make rust stains worse. The main ingredient in household bleach, sodium hypochlorite, is an oxidizer — and oxidation is the same process that can cause rust to form on metal. So while bleach can tackle a stain from last night’s dinner, it’ll only create more rust on your sunscreen-laden clothes. 

Instead, try addressing the sunscreen stain with a simple solution of two ingredients you have in your pantry already: distilled white vinegar and salt. While the acid in vinegar can decrease rust-related discoloration, the abrasive nature of salt essentially scrubs the stain off. Simply saturate the affected area in vinegar, then sprinkle with a layer of table salt and rub with your fingers. After soaking for two or three hours, rinse and wash as normal.