Why Do Black Trousers Turn Brown? (How To Remove Oxidation from Clothes?)


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Are you wondering why your trousers are turning brown? When a person says that their black trousers or other clothing are turning brown… there are several reasons this can happen.

Most people think that brown or reddish stains found on clothes are made because of iron. This is a common misconception… but it is not entirely true. Stains caused by iron use different mechanisms to make their appearance.

There are numerous factors that can cause brown or reddish staining… which in most cases also appear as rust. Below I will present you the most frequent causes of brown and rust staining along with tips for getting rid of them forever.

Why Do Black Trousers Turn Brown?

It may be an eternal mystery why the black pants you wear for work always end up with brown stains on them… but luckily… it’s also a simple problem to fix. You can go through cycles of removing the brown spots… but eventually… they’ll return if you don’t treat the underlying cause: sweat.

The salt in sweat is corrosive to almost any natural fabric… so it’s probably a good idea to stop wearing your best black pants when you’re at work. If you want to avoid staining your black pants from perspiration… try washing them with vinegar. The acidity of the vinegar will help break down some of the salts in your sweat and reduce the stains that appear on your clothing.

You should also give them a good soak in cold water before washing them. That helps remove lingering sweat and other odors so they won’t transfer to other clothes in the wash cycle.

Why Are There Brown Spots on My Pants?

Trousers that turn brown after washing are not just a problem with black trousers. Many other colors may also have this problem.

The brown discoloration of clothes can be caused by many factors… including water temperature and even the brand of washing powder used. The browning of clothes is known as oxidation.

When clothes are washed at high temperatures or with hot water… the browning is often caused by the fact that the washing machine has not been rinsed properly or there has been some sort of chemical reaction between the washing powder and the metal in the drum of the washing machine itself.

What Causes Brown Spots on Stored Clothes?

Cleaning your clothes and then storing them without air circulation can lead to oxidation and brown spots. When you put a garment into a plastic bag or a drawer without letting it breathe… oxidation occurs. Oxidation is caused by air being sealed in with the clothes and moisture from your body or the items you’re storing reacting with the fabric.

Oxidation is what happens to the fabric when it comes into contact with oxygen in the air for an extended period of time.

This is a natural process that occurs even with clothes that have been freshly washed… but the difference is that when those clothes are hung up and exposed to air… they’re getting a little bit of air each day so they’re not too bad.

But things stored in boxes or drawers or closets sometimes have months of being exposed to oxygen without being worn… which causes oxidation spots to form on the fabrics.

How Do You Remove Oxidation from Clothes?

A common problem for pants is brown spots… which usually occur in the crotch area. The cause is oxidation and a chemical reaction known as a reduction-oxidation (redox) process.

Oxidation occurs when oxygen interacts with the fibers of the clothes. When they are wet… water molecules dissolve into the fabric and introduce oxygen into the material. This causes oxidation to occur… resulting in discoloration.

The most effective way to prevent brown stains on your pants is to line-dry them instead of using a dryer. Line drying keeps the fibers of your clothes from being exposed to too much moisture… thus preventing oxidation from occurring.

If you must use a dryer… try drying your pants on a low heat setting or remove them from the dryer before they are completely dry. They should be allowed to air-dry for at least 30 minutes before wearing them.

Other methods for removing brown stains on clothing include using paper towels… rags or newspapers to pat out excess moisture from your pants after washing them. You can also apply white vinegar directly to the stained area before washing and then launder as normal.

What Causes Brown Stains on Clothes After Washing?

Brown stains on clothes are not something that you want to see. Not only do they look bad… but they also indicate that you might have a bigger problem going on with your washing machine. There are a number of things that can cause brown stains on clothes after washing. Some of the more common problems include:

1. Rust Stains (from Water Pipes)

Rust can build up in water pipes over time and when the water comes into contact with the metal in the pipes… it turns rusty red. When the water is forced through… it can turn your white clothes brown or even black. This can be a problem if you live in an older home where rust is starting to build up. In order to fix this problem… you will have to replace any parts of your water piping that are rusty and clean out any sediment accumulation at the bottom of your washing machine.

2. Lint (from Dryer Vent)

If your dryer vent is clogged… lint particles and other flammable materials could collect inside your dryer and catch fire when you turn on the machine for drying. This could burn a hole through one of your garments or cause some damage to your dryer itself.

If you’ve been washing your clothes in hot water… you might also notice that they’ve faded or developed brown spots over time. Most of these problems occur because of drying and storage issues rather than during washing. Also… if you’re using fabric softener or dryer sheets and leaving them in the washer for long periods of time… it’s going to cause damage over time.

How Do You Get Brown Iron Stains Out of Clothes?

There may be times when you accidentally get brown iron stains on your clothes. Perhaps you have been working with a hot iron and it has touched your clothes. Here is how you can get rid of the stain and make your clothes look great again.

Treating Brown Iron Stains On Cotton Clothes

The most important thing to remember when dealing with such stains is to treat them as soon as possible. If you leave the stain it will become harder to get rid of… so treat the stain while it is still fresh.

  1. The first step will be to wash your clothes in cold water. Do not put them in the washing machine; instead… hand wash them using laundry detergent and cold water.
  2. The next step will be to add a small amount of hydrogen peroxide to your clothes. This should be done only after they are washed in cold water and while they are still wet.
  3. Mix the hydrogen peroxide with ¼ cup of baking soda and add this mixture to your clothes.
  4. Let them soak for about 15 minutes… then rinse them well with clean water.
  5. After this… you can proceed to dry your clothes normally.
  6. Another option is to put them through the washing machine again using regular detergent… then hang them outside

What Gets Rust Out of Clothes?

Brown or rust-colored stains are typically a result of iron… either in the water or in your clothing.

Iron naturally occurs in our water supply and is often found in the water treatment process. When washing clothes with water that contains iron… the iron will leave a brown or rust-colored stain on clothing.

To avoid this problem… fill your washing machine with cold water only. If you have to use hot water… run it through the machine first before adding clothes to wash. If you have an iron filter on your faucet… you can use that to help remove the iron from the water before putting it in your machine.

Also… add a cup of white vinegar to every load of clothes to help reduce the amount of iron staining that might occur on clothing.

If you notice rust stains after drying your clothes… check inside your dryer for any loose lint that may be stuck around the drum area and clean it out if necessary. This will help prevent more rust stains from forming on your clothes in the future.

If you still have trouble getting rid of brown or rust-colored stains after trying these methods… you can also try adding some oxygen bleach to the load of clothes you are washing with warm water and no other clothing items.


In summary… if you have brown spots on your pants or other clothing items… there are a few ways to determine the cause. Once you’ve made this determination… you can make it easier to minimize future browning and stains. You only need to address the factors causing the damage. It may not always be possible but following these steps will reduce the odds of future browning.

You may also be interested in. 10 Styling Tips For Wearing White Shoes with Black PantsWhat Are Chino Pants Good For? and Why Are Trousers Called Slacks?