Non-toxic solutions for cat urine odor

The smell of cat urine can be incredibly strong and stubborn, but these non-toxic solutions can help eliminate these problems.

Janet has six cats. She loves them all, even though two of the males persist in urinating outside the litter boxes. Janet took them to the vet, but no physical problems were found. She’s now working with an animal behaviorist to resolve the problem, but in the meantime, her only recourse is to regularly scrub the spots the cats use as their bathrooms. “I’ve used every cleaner I can think of, even bleach, but the smell just hangs around,” she says. Janet adds that the three litter boxes sometimes smell too, even though she scoops them daily. “I’m sure people notice the odor of cat urine as soon as they walk in the door.”

Why is it so strong?

“Cat urine odor comes from bacteria that forms three or more days after the cat urinates,” say Mark Ventura, Product Development Manager for Arm & Hammer. “If some of the urine is not removed from the litter box, it will eventually collect on the bottom of the tray underneath the litter and form bacteria that emits a very strong odor. If a cat urinates on the floor, the same process can occur, leading to strong bacteria-driven odors.”

“Cats [also] have much more concentrated urine than dogs,” veterinarian Dr. Justine Lee writes on her website. “The normal concentration of urine is based on specific gravity…which measures the density of a liquid…. Normal cat urine specific gravity is greater than 1.040, while a dog’s specific gravity is normally 1.025 to 1.040…. What it boils down to is that dogs have much more dilute urine, which means it is less foul, less concentrated, and less yellow in color than cats’.”

Dr. Lee adds that the reason cats have concentrated urine is because they were originally desert animals with little access to water. “They have a very long ‘loop of Henle’, the part of the kidney that results in filtration and concentration,” she explains. “It’s so good at squeezing every last drop of absorbable water out that it makes the urine smell quite foul. Cats absorb a large amount of water from their urine to maintain their hydration, which also explains why you hardly ever see them drink – they’re so effective at concentrating.”

Effective odor removal

There are a lot of products on the market touted to get rid of smells of all kinds, including urine odors, but many of them contain toxic synthetic fragrances that can cause or exacerbate sensitivities in both people and cats. As well, a strong artificial perfume sprayed in or around the litter box may actually make the whole situation worse by driving the cat away from the tray.

“One safe, non-toxic way to remove odors from litter boxes is to use natural cat litter deodorizers, a class of products often sprinkled on top of the litter to remove odors,” says Mark. The deodorizer made by Arm & Hammer, for example, contains baking soda. “The baking soda chemically reacts with cat urine malodors such as ammonia, and neutralizes them,” explains Mark.

“If the odor is on a carpet or floor, then a pet odor and stain eliminator product that contains hydrogen peroxide would be a good, non-toxic way to remove it,” he adds. “The hydrogen peroxide oxidizes and destroys the odor molecules.” Choose a product that can be used on a variety of surfaces, including carpets, upholstery, linoleum or tile. “When purchasing non-toxic odor removal products, look for references for odor-removing technologies,” advises Mark.

Another option for odor elimination is to use an enzyme-based cleaner. The enzymes in these products actually eat and break down the urine, helping to get rid of the smell while they do so.

There’s no denying that cat pee has a powerful and persistent smell. But these non-toxic solutions mean you can eliminate the problem without resorting to masking fragrances or other chemicals.


Ann Brightman is Managing Editor for Animal Wellness Magazine and Integrative Veterinary Care Journal. A lifelong animal lover, she has also been a writer and editor for over 25 years. Ann is a member of the Professional Writers Association of Canada and is also a Tai Chi instructor.