Black mould. The words are sticky, dark, and poisonous, eliciting imagery of creepy masses growing in corners of bathtubs and windowsills.

How mould affects human health has been a concern since the 1940s, when toxic black mould, also known as “Stachybotrys,”first got its name.
According to an article written for the Huffington Post, this discovery may have been provoked by an incident in Ukraine in the 1920s, when thousands of horses became ill from a mysterious disease. Symptoms included excessive bleeding, irritation of the respiratory tract, nervous system issues, and even death. The cause? Mould.

Mould can make humans sick, but what about pets? Animals like cats and dogs are curious by nature, and so are at a higher risk of having contact with mould in places hard to reach by humans.

Signs Your Pet Might Be Exposed to Mould

Symptoms of mould exposure vary depending on the type of animal. According to Dr. Jennifer Coates, veterinary advisor for PetMD, there are a few tell-tale signs to watch out for, regardless of whether your pet has claws, hooves, or toes:

  • Respiratory problems, including sneezing, coughing, runny nose, wheezing or bleeding from the nose or mouth
  • Gastrointestinal symptoms like vomiting, diarrhea, decreased appetite, and changes in stool
  • Mould-related allergies resulting in excessive scratching, licking or hair loss


If your pet has symptoms related to mould exposure, don’t panic. The most important thing is to get it to a veterinarian and remove it from the home suspected of causing the illness. If there are other pets in the unit, they should also be removed, even if they are not exhibiting symptoms.

Treatment generally involves managing and supporting the illness with medication, administration of IV fluids, and fresh air.

Once your pet has been treated, ask your veterinarian if it is safe to bring your pet back into the home. You will likely be told to remove the mould from your home. If this is the case, it is imperative your pet be out of the house during the process, as it often stirs up the mould spores and could make the condition worse.

As long as they are treated properly, animals with mould-related illnesses tend to make healthy recoveries.

How to Prevent Mould Poisoning

  • Keep your pet out of areas likely to develop mould, like basements, bathrooms or crawlspaces.
  • Frequently clean your pet’s food and water dishes, toys and bed and linens.
  • If you live in an older unit, consider hiring a professional to test for mould.
  • If your animal spends part of its time outdoors, be sure to discourage it from eating or playing with trash.

Pets are special creatures, and it is important to reward their companionship with a safe and healthy home. Mould is dangerous, and a serious threat to your pet’s well-being. Be sure to consider this guide if you ever suspect your pet of mould poisoning.