Is Cat Litter Toxic?

Many people in the world will have a cat or  a few cats as a pet. The question that we are trying to resolve, is are there genuinely any health risks for humans, by having a cat for a pet?

In particular, what potential health risks are there when it comes to having a cat litter (s) in the home. After all there is the litter material itself, and then the urine and feces of the cat to contend with.

We will look at this in great detail and use the best medical and scientific evidence to explain what the real risks are. This is a long article, but we think it fully explains the risks, and more importantly, what cat owners can do to keep any potential risks to a minimum.

This is especially important for families with small children and families with other pets.

Known Health Risks With Cat Urine and Feces

There are medically proven known risks with both cat urine and cat feces, some of which can be fatal to humans. There are also a few known breathing issues, caused by contaminants in the air from certain types of cat litter.

This is usually the dust that is created when the litter is in transit. We shall explore all of these below in some considerable detail.

According to the National Owner’s Pet Survey  68% of US households own a pet and that equates to about 85 million families. Of those 60 million have a dog and 47.1 million households have a cat. There is of course homes with both a cat and dog, or numerous pets and hence the overlap in the numbers.

The actual number of cats in the US is 94.2 million. That takes account of homes that have 1 or more cats and also stray or feral cats.

With these large numbers, it is certainly worthwhile investigating the health risks associated with cat litter, cat urine and cat feces, in a lot more detail.

It is worth pointing out at this stage, that cat litter itself sitting in a bag or box poses no health risk to a human. It is only when it is used or contaminated that risks begin to arrive.

Is Cat Feces Toxic or Poisonous to Humans?

The quick answer to this is a resounding yes. There are two very well known illnesses which are E.coli and Toxoplasmosis. These can come directly from cat faeces. Let’s have a look at each in more detail.

I want to begin though by stating that not all cat waste contain these, but they have the potential to, and that makes it worth your consideration. Toxoplasmosis is normally found in cats who eat rodents, birds and under cooked or raw meat.

When this happens then cats become a carrier of the toxoplasmosis parasite. I will explain this in more detail below.

Escherichia Coli Bacterial Infection

This is better known as E.coli, and there has been a lot of talk about that illness on the news. It is a bacteria which is responsible for various infections.

If inadvertently ingested, normally from eating cat feces, this bacteria can lead to severe abdominal cramps and bouts of diarrhea.

Some pets, mainly dogs will do this, and it has been known for children to inadvertently do this, from litter boxes, especially the open style litter trays.

Humans touching used cat litter, and not washing their hands immediately, can also accidentally get this into their digestive system.

This will need medical treatment, and an antibiotic treatment is always required to cure E.coli infections. The cat poop or dropping does however need to be eaten and digested for this to become a concern.

Toxoplasmosis (T.Gondii)

A long word I know, and this is another common infection that happens in humans and is caused by cat feces. It is well known that many cats poop in the backyard, in sand or even in soil instead of their designated litter box.

When that happens adults working outdoors at a garden for example, can easily come into contact with cat feces.

Likewise children playing outdoors in gardens, uncovered sand boxes and sand pits can also come into contact with cat feces. No matter how careful we might be, it is always possible to touch cat poop without knowing it.

After all there are many public parks and many wild cats in them.

Even in a cat litter box there will be feces. If the cat is carrying the parasite, then this poop is also dangerous to humans.

If a women is pregnant than Toxoplasmosis can be fatal to the fetus. This is certainly one illness that you want to avoid at all costs. Healthy adults generally speaking have a strong immune system that prevents any symptoms from showing up. Older people or those with weaker immune systems are not so lucky.

If you would like to read about pregnancy and cat litter in more detail, please click here.

Toxoplasmosis gondii is the parasite that leads to toxoplasmosis. Cats act as carriers of this parasite, and it escapes through their feces in the form of oocysts.

These oocysts are small micro organisms that can very quickly reproduce. They have an incubation period of between 1-5 days, so regular daily cleaning of the litter box will always keep that problem under control.

If they contact this then some of the symptoms can be a high fever and severe bouts of diarrhea. There are also plenty of studies that show Toxoplasma can alter our personalities.

In some cases it has been shown, that for infected women 54% were more likely to attempt suicide, among other disturbing side effects.

I think you will agree that there is enough evidence to make this a huge concern.

Roundworm Eggs and Larvae Toxocara Cati

Now if those two are not enough, it is also possible that cat feces can contain roundworm and larvae. Roundworms are intestinal parasites that are common in kittens and cats. The first type is known as Toxocara cati.

This is seen commonly, and especially in small kittens. This normally happens when they ingest this from the mother’s milk. They can also get these from eating rodents, and get into their lungs, and eventually end up getting coughed up. These larvae can infect humans.

During this process the larvae become adult roundworms in the intestines and lay a lot of eggs, which are passed in the feces.

Toxaxcara leonina

The second type is known as Toxaxcara leonina, and is less common, and is usually seen in older cats. In almost all cases, this larvae does not infect humans. To treat these it will mean treatment from a vet, and they will offer the best type depending on the age of your cat, and its condition.

In terms of the impact on humans, these infections are most common in children, and also in gardeners who do not use gardening gloves. This also include gardeners who do not wash their hands when they have been working in the soil or in the garden.

People can accidentally pick up eggs on their hands. This happens when children are playing or when gardeners are working in the soil, which cats have used for a litter, and are infected. Good hygiene is vital, especially hand washing.

It is also a good idea to cover sand boxes, and try to keep cats out of areas where kids play. It is also really important to pick up any cat poop when it is seen, wearing gloves of course, and properly disposing of it. Many gardeners will kick this into the soil and dig it in believing it works as manure. Nothing could be further from the truth.

Is Cat Urine Dangerous for Humans?

Yet again, the answer is yes. There are few smells more potent than that of cat urine. Now apart from the very strong smell, if cat urine is allowed to sit around for several hours, it begins to emit ammonia. This can very quickly lead to allergic reactions in human beings, including both adults and children.

In fact children have a lower immunity to ammonia, and a lighter body weight. Because of that, they have an even higher risk than adults. The same high risk applied to anyone suffering from bronchitis, pneumonia, COPD, asthma or any type of respiratory condition.

Typical symptoms include coughing, vomiting, general nausea, headaches, sneezing, itch skin especially around the nose area, dizziness and red eyes.

Cat urine like any human or animal waste carries bacteria. The best thing you can do is to regularly clean the litter box, and make sure that your cat is always using it. There will always be a smell with cat urine, however you want to be certain that the smell does not get too strong, as that is when the risk will increase.

How To Prevent Risk From Cat Feces

There are some general precautions anyone can take to greatly reduce the risk of contacting an illness that can be caused by cat feces. There are also some specific ones with reference to cat litter, and cat litter boxes.

General Precautions When Handling Cat Litter

  • Always wash your hands if you have been doing any work outside. It is now common practise for many gardeners to wear gloves when working in the soil. That helps prevent your skin from coming into direct contact with animal urine and feces. When finished gardeners should of course still wash their hands.
  • Dogs, cats and rats will use soil to do their business. So as well as using gloves, always take time to thoroughly wash your hands, after a spell working outside.
  • This is a very important thing to do with children. It is a very wise thing to educate them on the importance of hand washing after they have been playing outside.
  • Cats in particular are very fond of using sand pits to urinate and do their feces and even cover it up in those pits. It can happen at any time, and children playing in a pit with cat feces present are at very high risk.
  • The same washing hands rule applies to petting cats and other animals. It may be a cute thing to pet a cat or dog, but the reality is that you have no idea if they are carrying some type of infection.
  • If you have a vegetable garden or grow fruits at home, then make sure that these are thoroughly washed before consuming them. Domestic animals and other wildlife will regularly do their business in garden soil. The last thing you want to do is to digest that. Take some time and make sure that all fruit and vegetables grown at home are washed and cleaned.
  • Fruit and vegetables bought in a store should have gone through a cleaning process, but it does no harm to also wash those before you eat them
  • We have mentioned sand pits, and those are a favorite haunt of cats. When not in use either bring them inside a garage or shed. If that is not possible, then make sure they are covered.
  • Many cats prefer using sand to do their toilet habits rather than a cat litter. An open sand pit in a garden will attract cats, and by covering it when not in use removes that potential risk.

Cat Feces and Cat Litter Boxes

The golden rule here is to never place a cat litter tray or box on any area that has carpet on it.

Often cats will not use the litter box but will pass urine close to that area. That means that the urine can very quickly get into areas of carpet or rugs.

Most cats, even those that do use their cat litter box, will sometimes just not do that. They like their privacy and they will go behind the box, or even close to it, and do what they have to do.

Clean this up as quickly as possible otherwise you really do increase the risk of catching an illness.

Kids and especially babies and toddlers will crawl around floors, and it is very easy for them to become infected.

The best way to clean this up is not to rub the area at all. That will only spread the bacteria and make it worse. Use tissues to dab the area clean and wear gloves as well. In essence you are trying to absorb as much of the urine as possible.

There are also plenty of Hydrogen Peroxide commercial cleaners and disinfectants that can be used to help kill off any bacteria. The best result is to take quick action.

Never used ammonia based cleaners as they react with the urine ammonia and only make the mess worse. If you don’t have Hydrogen Peroxide, then use either vinegar or baking soda to absorb the urine.

One useful tip is to use either a pine sawdust, or a cedar sawdust in the litter. Both of these are known to quickly absorb urine and they also prevent urine crystals from forming. This helps prevent ammonia from forming.

Lining a cat litter box is also a good thing to do. There are plenty of liners available on the market, and it makes the whole process of emptying a litter box very fast to do.

The Dangers of Cat Litter Dust

Cat litter dust is caused when cat litter is being transported. Dust is not actually used as an ingredient. When cat litter is in transit, the particles rub together and it is this friction that causes dust to be created.

When an animal is low to the ground, then the risk of breathing in microscopic particles of dust increases.

Cats are high enough not to be concerned wit this, but some smaller kittens, are quite naturally lower to the ground. There has not been any research, or I certainly could not find any, where the risk has been assessed.

You can read more about how to reduce dust in a cat litter by clicking here.

We have included a section below on Silica Dust, that is found in some cat litters.

Is Cat Litter Toxic to Humans?

The answer to this is no. In itself cat litter is certainly not poisonous or toxic to human beings. Cat feces and cat urine as I have explained do have potential risks, but cat litter as a stand alone product does not.

However once the litter has been used for cat waste, then that changes to being potentially harmful as explained above.

Is Cat Litter Toxic for Toddlers and Babies?

The answer is the same as the one above. The bigger risk is that toddlers and babies can inadvertently end up playing with a cat litter inside the home, or come into contact with cat poop outdoors. This is a concern for babies who have just started to crawl, and make their way around your home.

As you may already know, even if the child doesn’t get into the actual litter box, many cats do what is called “trailing or tracking.” That means that litter gets stuck to their paws, and when they leave the litter box, this can get trailed across the surrounding area.

Many new parents use a litter called “Tidy Cat Breeze” to help get around this problem. This litter does not attach to the feet of cats and as such will reduce the tracking problem.

Some other parents recommend “World’s Best Cat Litter” as they said it is made from natural products. You can read about using natural cat litters by clicking here.

Other than that it makes sense to use a covered litter box, and to have the opening facing the wall.

That way your cat can still get in, and the entrance remains hidden from the child. Some parents use top entry boxes for the same reason.

The best cat litter boxes to use are those that self clean, as that automatically removes poop and clumped litter as soon as it is left there by the cats. The problem is of course that these are always more expensive that a standard box.

Some parents make use of baby gates and make sure the litter box is located anywhere on the other side of the gates. That is probably the safest method to keep crawling babies and toddlers away from the litter box.

Is it Bad to Breathe in Cat Litter?

Is there really a danger breathing in cat litter fumes? There are really three elements to this question, which need to be examined.

  1. The effects of breathing in cat litter dust
  2. The effects of breathing in cat litter urine
  3. The effects of breathing in cat litter feces

It is important first of all to fully understand that there are different types of cat litter available on the market. It is known that “Silica Dust,” used in some cat litters can cause an illness known as Silicosis.

This is a known lung disease that causes inflammation of the lungs, and eventually results in difficulties with breathing.

However, the consensus seems to be that when cats lick themselves in a litter, then pieces of the litter get eaten, and that is a bigger concern. If this litter contains sodium bentonite, then this can swell up and cause blockages.

Many people also believe that this same lung issues can also affect humans. There is no scientific research or medical research that supports this, though the concern is obvious. After all if it affects your cat’s breathing, then it certainly can not be a good thing for the cat owner.

If this is a concern, then the recommended advice is to change your cat litter to one that doesn’t contain any sodium bentonite, and use something made of wheat or corn. Other advice is to wear a dust mask when filling or cleaning a cat litter.

As I mentioned there is no research available that I could find on this topic, and I did look very hard to find any that was existing online. The only comment that I would make is that with over 90 million cats in the US alone, surely this would have been found to be a problem by vets. If that was the case, then I assume some type of research would have been done.

When someone is scooping the litter box or doing a complete change of the litter, that action may create or stir up a slight cloud of dust. That odes of course depend on the type of litter that you are using. The dust is sometimes visible but that may not always be the case.

If you inhale contaminated kitty litter dust, the toxoplasmosis parasites can get into your system. This of course assumes that your cat is carrying the parasite Toxoplasmosis gondii in the first place. They get this from eating infected rodents or from eating raw meat.

Something as simple as scooping out a contaminated litter box and then making yourself a sandwich without washing your hands, can mean that you will inadvertently end up accidentally swallowing contaminated droppings. That is why it is vital to always wash your hands after cleaning out the litter box.

I mentioned that there is also the risk associated with cat urine smell, and I have covered that just below in a little more detail.

Cat Litter – Ammonia Poisoning

Let’s face it a cat litter box is just a toilet for a cat. There will be smells and odors, and the worst one is the smell of cat urine. This stench is caused by ammonia in the cat’s urine. Now although the actual amount of ammonia is small, it is actually quite concentrated as cats do not drink a lot of water.

In case you have never checked too closely cat urine is an amber yellow color, and gives an idea of its strong ammonia concentration. Short term exposure to any type of ammonia is not that big of a concern. Long term exposure is however not recommended as that can lead to eye and nose irritations.

It is also worth noting that this smell is easy to get used to if you live with it every day. As such it can build up without the home owner realizing that the levels of ammonia are getting higher. If left undetected, and levels increase, this can result in asthma.

Pregnancy and Litter Boxes

Anyone who is pregnant or considering a pregnancy should never clean or be anywhere near a cat litter box. As cat feces may carry toxoplasma gondii it can affect the immune system of a pregnant woman.

Most people have a strong enough immune system to deal with this parasite, but in pregnancy, that is not the case.

The risk does not come from the smell of the litter box, but from its contents, which is why they should avoid cleaning the litter, or replacing the litter.

According to the Centers Disease of Control and Prevention, pregnant women should avoid adopting a new cat, a kitten or a stray cat, and should avoid changing cat litter. If no one else can perform the task, pregnant women should wear disposable gloves and wash their hands with soap and warm water afterwards.

The Dangers of Not Cleaning a Cat Litter

I think by now you will understand that not a lot of research has been done in this area. Many of the concerns expressed are based on anecdotal evidence and assumptions. We do know for certain that if cats are outside and kill rodents or birds, or eat raw meat, then they can become a carrier for toxoplasmosis.

This is then passed into the litter box and is in the cat feces. This parasite takes around 5 days to develop. To avoid any potential risk it is imperative to keep the cat litter box clean. That means daily and even twice daily removal of feces and clumped litter.

It is also highly recommended that the litter is fully replaced once a week. Any cat litter should be put into a plastic bag and sealed, and then put into the waste. When changing a cat litter gloves should be worn and a mask is also a great idea. Hands must be thoroughly washed when a cat litter has been scooped out or cleaned.

Cats do not like dirty litter boxes, and they will stop using them if they become too smelly. Aside from that, they also smell really bad if not properly cleaned. A dirty litter box can also cause problems for human health. Ammonia build up is a concern that can easily go unnoticed.

Litter Box Advice for Your Best Health

  • Do not ever place litter boxes in a kitchen or anywhere that you eat
  • Clean the box from poop or clumped litter at least once a day
  • Always wash your hands anytime that you replace or clean litter
  • Change the litter completely once a week
  • Seal and dump the litter in a plastic bag or liner and never dump it straight into your bin
  • Wash the litter box once a week with hot water and a mild detergent
  • If your immune system is low such as when pregnant or elderly, then stay away from changing cat litter

We do of course all want to enjoy our cats, but we also want to stay safe and keep our children and other pets safe. Cats that are always indoors are much less of a risk, that cats who are both indoors and outdoors.

There is no way of knowing what your cat is eating when it is out and about on its travels.

This was a very long article, but I hope that you found it useful. There is not a lot of actual scientific or medical research available online, which is a pity as I always like to write may articles based on fact, rather than on what some people think.

If that changes I will of course update this article. Clearly cat urine and especially cat poop hold their own risks for humans as at the end of the day, it is animal waste. Keeping litter boxes as clean as you can will go a very long way to minimizing any risks.

Cats that live indoor pose a much lower risk than those cats who are both indoors and outdoors.

In terms of cat litters, there are lots of choices. Vets have not noticed any common or recurring problems, and there is simply no credible research to prove one way or the other if they are harmful.

Resources Used

American Pet Products

WebMd – Escherichia Coli Bacterial Infection

Wikipedia – Toxoplasma_gondii

Wikipedia Toxocara cati.

Research Vet – Toxaxcara leonina

Pub Chem Government website – Hydrogen Peroxide

Wikipedia – Silicosis

CDC Government website – Centers Disease of Control and Prevention​

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