Although, in the UK, the chemical metaldehyde has been banned from slug pellets from the Spring of 2020, because it is just too toxic to animals, there will be old stocks of pellets in garden sheds which contain the chemical and I’m sure that in many other countries these toxic slug pellets are available and will be available well into the future. Hence this word of warning if you are unaware of the danger. It is timely as there is an infestation of slugs in the UK due to warm and wet weather.
It is prudent to be aware of the toxicity of this chemical. It kill slugs by dehydrating them. It prevents the mucus being formed outside the body which causes the slug to become bloated and die. It is effective but a safer and perhaps equally effective method of killing slugs is a small worm, a nematode, which you can buy online or from breeders in the conventional way.
The worm enters the slug through their breathing apparatus and then deposits bacteria inside the slug which kills it. Apparently the many other methods are less effective. Some place a copper wire around their plants or bury cups of beer or scatter egg shells. Beer traps catch larger slugs but not the smaller ones and it is those that do the most damage as they don’t travel as far. Beer traps only catch slugs that are close.
The wider issue really is that around the home there are numerous possible toxic chemicals in household and garden products. The list is too long to name here. Think of weedkillers for instance. They are also toxic to pets and people. And there are many plants both inside and outside that are potentially toxic which can kill cats such as lilies. Lily pollen in even small amounts can seriously harm domestic cats.
With respect to slug pellets, there is a story online about a Japanese Akita dog, Boris, who was out walking with his owner in the early hours and he apparently walked on some pellets or sniffed them. That was enough to kill him because he licked his lips and his paws thereby ingesting the metaldehyde into his body. Within half an hour he had lost the use of his legs and he was euthanised soon afterwards. It is an horrific story of an innocent and inadvertent encounter with slug pellets which you simply wouldn’t recognise at the time but which ended in devastation for this family.