Sniff test: Keep your pets away from these scents

You know that feeling when you walk into your whare after a big clean, and everything smells fresh? The windows are open, the candles are lit, and it feels calm and cosy.

But while you may love that burst of vanilla, citrus or ‘ocean spray’, your dog or cat is experiencing something very different.

Our pets live through their noses. A scent that barely registers for us can be intense, irritating or even stressful for them. In some cases, everyday household fragrances, from diffusers to cleaning sprays, can trigger breathing issues, anxiety, or litter tray avoidance.

With insights from veterinarian Dr. Emma Ruck BVSc (Dist) MANZCVS, here’s what to watch for and how to keep your home fresh without compromising your pet’s wellbeing.

Why strong scents can be harmful to pets

Dogs and cats experience scents very differently from people. Dogs have up to 300 million scent receptors, compared to around 6 million in humans. While cats have up to 200 million scent receptors! What smells mild to you can feel intense to your canine and feline friends.

Dr. Ruck explains that strong scents can affect pets in three main ways:

Respiratory irritation

Scented products release airborne chemicals that can irritate the nose, eyes and airways.

“This is especially problematic for pets with allergies, respiratory sensitivity, or shortened airways, e.g. brachycephalic breeds of dogs and cats,” Dr. Ruck says.

You might notice:

• Sneezing or coughing
• Watery eyes
• Reverse sneezing
• Avoiding certain rooms

Stress and sensory overload

Constant fragrance can overload a pet’s sensory system.

“Many pets learn to associate the smell of a place with the experience they have there,” Dr. Ruck explains, “This can contribute to feelings of fear and anxiety when detecting this scent in future.”

For example, the chemical smells, or fear pheromones detected at the vet's clinic, kennels or grooming facilities can be stored in your pet's memory bank, negatively impacting their emotional response in future visits.

Signs of scent-related stress include:

• Restlessness
• Panting or lip licking
• Increased vocalising
• Shaking or scratching
• Difficulty settling

Over time, this can impact behaviour and emotional regulation.

Toxic exposure

Some scented products and essential oils contain compounds that can be harmful when inhaled, absorbed through the skin, or ingested during grooming.

Cats are particularly vulnerable because their livers process certain chemicals differently from dogs. But both species can be affected.

Scented candles, essential oils, and rock lamps: What to avoid

Some of the most popular scented household products can pose real risks to pets, especially in enclosed spaces. What may feel relaxing to you can irritate sensitive airways, overwhelm their sense of smell, or, in some cases, lead to toxic exposure. Here’s what to be cautious about in your home.

Scented candles

• Choose unscented or lightly scented natural wax (soy or beeswax)
• Ensure good ventilation
• Keep flames well out of reach

Essential oils

Common oils considered risky include:

• Tea tree
• Eucalyptus
• Peppermint
• Cinnamon
• Clove
• Citrus
• Pine
• Wintergreen

Avoid:

• Diffusing oils in enclosed spaces
• Applying oils directly to pets
• Leaving bottles accessible

The impact of strong cleaning products and scented cat litters

Cleaning products might make your home feel sparkling and fresh. But to your cat, that sharp chemical scent can be deeply aversive.

“Strong cleaning products can be aversive to your cat, leading to them avoiding using their litter tray and seeking another spot to toilet – often on bedding, clothing or carpet, which can be very difficult to clean,” Dr. Ruck explains.

Scented litter is generally less bothersome than strong cleaners, but some cats still dislike them.

Another factor? Communication

Cats rely heavily on scent marking to maintain social bonds and establish territory. Overpowering fragrances can interfere with this communication and potentially increase tension between cats in multi-cat households.

If you’re dealing with toileting issues, it’s worth reviewing:

• Litter type
• Scent level
• Tray cleanliness
• Location (quiet, low-traffic areas are best)

Safe alternatives to keep your home smelling fresh

You don’t need a heavy fragrance to have a fresh home. Instead, try these pet-safe options:

• Ventilate first by opening windows and doors regularly to circulate fresh air – take care to contain any indoor pets first.
• Use unscented cleaning products and prioritise pet-safe formulations
• Limit fragrance to pet-free, well-ventilated spaces
• Wash pet bedding regularly with mild, unscented detergent
• Address the source of odours (dirty litter boxes, damp areas, bins) rather than masking them

Most importantly, keep a close eye on your pet’s behaviour. You know them best, so you’ll be able to notice if they are acting out of character.

Dr Ruck says that if a pet becomes unsettled, vocal, or begins avoiding an area after a new product is introduced, the first step is to remove that new item and observe whether the pet’s behaviour improves.

Other common household items that can stress cats and dogs

While scent is a big factor, it’s often part of a wider sensory load in your home.

Dr. Ruck notes that pets can also be stressed by:

• Vacuum cleaners, lawnmowers, hair dryers, and food processors and blenders
• Appliances that beep (ovens, microwaves, smoke alarms)
• Electronic devices that emit ultrasonic sounds
• Slippery flooring, especially for pets with arthritis or hip dysplasia
• Brooms and mops
• Scooters, bikes and prams
• TVs showing other animals like barking dogs or wildlife documentaries
• Creaking or banging doors on windy days

For cats, litter tray hygiene and placement matter just as much as scent.

“Even the sight of a patch of wet litter can cause some cats to avoid the tray,” Dr. Ruck says, “Placing a litter box next to a noisy appliance like a washing machine can also create stress.”

If your cat starts toileting on bedding or carpet, it’s often a form of communication, not bad behaviour.

Salt (rock) lamps

Another household item to be mindful of is Himalayan salt lamps. While they may look calming, they can prove dangerous to pets if they lick or chew one – causing ingestion of dangerous amounts of salt.

Symptoms of salt toxicity include:

• Vomiting and diarrhea
• Tremors
• Seizures
• Severe neurological issues

Cats are particularly susceptible to salt lamps because they can easily access tables and counters, and may sniff or lick objects that catch their interest.

Protect your pet’s sensitive snout

Even with our mind set on providing a safe space for our pets, accidents can still happen (and often do!)

If your dog chews through a bottle of essential oil or munches on a fragrant houseplant, treatment can become both urgent and expensive.

Pet insurance can help cover eligible vet costs if your pet suffers from an unexpected illness or accident. Learn more about SPCA Pet Insurance to see if it’s something that could suit you and your pet.