A recent TikTok upload from video maker Nicole Susan (aka The Butterfly Garden TT) depicts her success in using snail and slug bait to deal with unwanted African black snails – is it poisonous to dogs?
The video has attracted 63 comments, at time of writing, and nearly 200 likes.
The snail and slug bait the OP appears to have used is from Caribbean Chemicals’ Tropi-Gro brand, and contains instructions to “keep out of reach of children”.
But can it harm dogs? Are there any warnings against using it in areas where pets might come across it?
Is snail and slug bait poisonous to dogs? What is it?
Snails and slugs can be the bane of gardeners’ lives. One of the solutions, for those who really want to keep the pests at bay, is bait.
Pellets and baits designed to clear gardens of snails and slugs work in two ways. First they contain attractants, which lure snails and slugs.
Second, they contain poison, so that when slugs and snails eat the pellets or bait, they die. These molluscicides come in three main forms, on which more below.
The important thing to note, for now, is that yes, metaldehyde, which snail and slug baits contain in order to kill pests, can have “devastating and even fatal” effects on cats and dogs, if they accidentally eat them. A natural alternative is wool pellets, such as those below.
What is it about snail bait and slug pellets that makes them so unsafe for dogs and cats?
Snail baits and slug pellets contain three main types of poison, according to Slug Help.
These are iron(III) phosphate, metaldehyde, and methiocarb. Each acts differently; some pellets, such as those containing methiocarb and/or metaldehyde, can even be lethal to humans, and can pollute groundwater.
Metaldehyde causes slugs and snails to die from water loss. It is known as a “contact poison”, meaning animals don’t actually have to eat it to suffer its effects.
After it touches a bait or pellet containing metaldehyde, a snail or slug will begin to produce excessive amounts of slime, Slug Help writes, in order to flush the toxin out of their system. This causes them to die from dehydration.
What happens when a dog eats snail bait?
Preventive Vet writes that metaldehyde, the active ingredient in many types of snail bait and slug pellet, is “extremely poisonous to cats and dogs”.
“Eating as little as 1oz of 3% metaldehyde can cause toxicity in a 10lb dog.” But it doesn’t do so by causing dogs to produce slime, obviously. So how does metaldehyde harm household pets?
Within one hour, Preventive Vet continues, a cat or dog that has ingested metaldehyde via snail bait may start to: vomit, because of the irritation to the stomach; become anxious, due to an increased heart rate; lose muscle control; become hypersensitive; and experience muscle tremors.
Decaying muscle cells release myoglobin, which can make its way into your pet’s urine, turning it ominously dark. Weakness, seizures and even loss of consciousness can follow.
Any pet that has eaten a metaldehyde-based slug or snail poison will require an “immediate veterinary evaluation”. Do not “wait and see”, PV stresses. And, incidentally, the active ingredient in the snail bait from The Butterfly Garden TT’s TikTok video is metaldehyde.
So snail bait containing metaldehyde is not safe for dogs – what about the others?
Not all snail baits and slug pellets contain metaldehyde – which is not safe for your household pets, such as cats and dogs. But that doesn’t mean they’re any better overall.
The most common snail and slug poison, according to Slug Help, is iron(III) phosphate, or ferric phosphate. Note that the Roman numeral in the brackets refers to the number of electrons the element has lost in the process of oxidisation.
Iron(III) works by blocking the throats of snails and slugs. It usually takes a few days to kill them, during which time they may still reproduce, and will often find a place to hide in which to die. This mean their corpses, uncollected, will produce a smell of decay, which may attract more slugs from nearby areas.
Methiocarb, while common in the 1990s, is now illegal in numerous countries. It is fatal to dogs, humans and earthworms.