Ask Dr. Pete: How to Remove Common Pet Stains

Getting a new puppy or kitten might be one of the most exciting moments of a fur parent’s life, but as many of us know (or will discover) extraordinary cuteness requires patience and some specialized cleaning tips. 

The most common types of stains you’ll probably encounter are biological stains like urine and feces, and anything else they might bring in from the outdoors. Whether caused by accident or possible intentional motive (cue cat parents), Dr. Pete breaks down the science of why these stains are so tough and how to get rid of them. 

Pet Pee

What's in pet urine?

Puppy and cat urine have nitrogen-rich compounds like ammonia, creatinine, uric acid, and biological substances such as hormones and pheromones in water. The hormones are organic chemicals that act inside the body of a pet. Pheromones are volatile substances with distinctive smells, and they act on pets of the same species by changing their awareness and behaviors.  For example, MMB* is a sulfurous odorific pheromone in the cat urine that cats use to mark their territories and scare off predators. 

*You can learn more about the notorious, odorific nature of cat urine here. 

Why is it hard to remove?

When pet urine is fresh and warm, it is slightly acidic with pH at around 6 at which uric acid is more soluble in water to be cleaned off.  Once pet urine has aged, it is much harder to remove and clean off.  The ammonia concentration increases, which makes the urine more alkaline with a pH above 10. The solubility of uric acid and its salts at this higher pH becomes much less soluble in water, resulting in crystalized uric acid and slats that bind to washable fabric and upholstery surfaces. Once urine stains are aged, the hormones and pheromones in the urine attract bacteria and react with oxygen in the open air, which generate a complicated mix of organic substances. Those organic substances tend to tightly ingrain with the fabric substrate, dye the fabric material with yellow or greyish colors, and often release malodors over time.

How to remove fresh urine stains:

1. Remove any excess urine from the fabric with a white paper towel or cloth - ideally as soon as possible.

2. Thoroughly rinse the fabric with warm water.

3. Pretreat the urine stain for 5 minutes with our Bio Laundry Detergent by dabbing a small amount of detergent directly on the stain. The enzymes in Phytolase® will get a head start on working on the stain.

4. Machine wash the stained fabric with our Bio Laundry Detergent in a warm wash setting. Avoid cold or hot water to prevent accelerated stain setting caused by the crystallization of uric acid and oxidation of hormones and pheromones

*In aged pet urine stains, uric acid and its salts have crystalized and bound to fabrics in high alkalinity. Aged hormone and pheromone complexes  have oxidized and become infested with bacteria. As a result, an aged urine stain will dye fabrics with a yellow or grayish color and release a very distinctive malodor. To address this situation, a bio laundry detergent containing enzymes and surfactants may not be effective enough. We created an advanced Bio Enzyme Laundry Booster with a new bioenzyme that is specifically designed to break down biological stains. The oxygen in the booster releases hydrogen peroxide during the pretreatment and machine-washing cycle while the advanced bioenzyme helps to break down the complex biological stains. The activated oxygen is effective in decomposing the organic materials having heterocyclic rings and unsaturated double bonds, such as hormones, pheromones and chromophores.

How to remove aged urine stains:

1. Pre-treat or pre-soak the urine stain with a combination of our Bio Laundry Detergent and Bio Enzyme Laundry Booster for 30 minutes. 

2. Machine wash the stained fabric with the same combination of detergent and booster by following the use instructions of each product, apply hot water and steam or heavy-duty wash cycle;

3. Repeat the above pre-treat and machine wash steps until the aged pet urine stain is satisfactorily removed.

Pet Poo 💩

What’s in it?

Dog and cat feces are composed of solid and semi-solid food remains, metabolic waste such as nitrates and sulfates, toxic bacteria, and parasites. 

Why is it hard to remove?

The food remains, metabolic nitrate and sulfate waste, bacteria and parasites are not stable in the air. They react with the oxygen to form a complex that binds to fabric materials. They release chromophores that dye the fabric materials with colors and malodors during the process. For example, Skatole is a heterocyclic nitrogen-containing molecule that creates typical feces malodor.

How to remove pet poo from fabrics?
While our concentrated Bio Laundry Detergent should sufficiently remove any biological stains caused by pet feces, our most preferred option is to use the combination of our Bio Laundry Detergent and Bio Laundry Booster in dealing with the bacteria and chromophores in the feces.

How to remove poo stains:

1. Remove any excess stain with a paper towel or cloth as soon as possible. 

2. Thoroughly rinse the stain with warm water;

3. Pretreat or pre-soak the stain spot for 15 minutes with a combination of a Bio Laundry Detergent and Bio Enzyme Laundry Booster;

4. Machine wash the stained fabric using our Bio Laundry Detergent and Bio Laundry Booster in a warm wash cycle. Avoid hot water to prevent accelerated stain setting caused by the accelerated oxidation of any unstable chemicals in the feces.

5. Repeat the above pre-treat and machine wash steps until the aged stain is satisfactorily removed.

Mud and other gross things

What actually is mud?

While we all know what mud looks like in a general sense, what’s in it can vary based on where it came from and what brought it in. Some common ingredients in mud include: 

• Soil, silt, loam, or clay mixed in water, which can include hydrated minerals of silicate, iron, and aluminum oxides. These materials can carry different colors depending on the metals in them.. For example, iron oxide makes the red color commonly associated with clay. 
• Grass, which contains protein, lignin, cellulose and chlorophyll. Chlorophyll is the pigment that makes grass green. Chlorophyll is also an effective dye, especially for natural fabrics like cotton, wool, linen, and silk.
• Sweat. While dogs and cats don’t sweat in the same way as their human parents, they do have sweat glands in their paws to help them cool down. Pet sweat can add another layer of complexity to mud because their sweat contains proteins, triglycerides, free fatty acids, hydrocarbons, carbohydrates, squalene, bacteria, bioactive hormones, and pheromones that can release malodors.
• Urine, feces, and other biological materials. 

Why can the mud brought in by pets be hard to remove?

The composition of the mud carried in by your pets can be relatively simple, e.g., just soil or clay in water, which is relatively easy to remove. But if the mud is a mix of all the components listed above, it can get pretty difficult due to the complexity of the stains. Chlorophyll, hormones, pheromones and proteins can react with the oxygen in the open air, and the oxidation reaction gets accelerated at higher temperatures to bind tightly to the fabric materials.

For simple mud stains:

1. Pretreat the spot with our Bio Laundry Detergent by applying a small amount and spreading it over the stain. Let it sit for 5-10 minutes. 
2. Machine wash items in a hot wash and cold rinse cycle. 

For complicated mud mixtures:

1. Presoak the stained items with a combination of of Bio Laundry Detergent and Bio Enzyme Laundry Booster.
2. Machine wash the stained items using the Bio Laundry Detergent and Bio Enzyme Laundry Booster in a warm wash and cold rinse cycle. Be sure to follow fabric care instructions. Avoid hot water with more complex mud stains due to potential oxidative components that will react more quickly with hot temperatures. 
3. Repeat the above pre-treat and machine wash steps until the aged pet urine stain is satisfactorily removed.