Cocoa Mulch is also known as 'Cocoa Bean Mulch' or 'Cocoa Shell Mulch' and is used as a mulch in home gardens in some countries. It is a byproduct of the manufacture of cocoa powder and other chocolate products. There have been several reports of pets being poisoned by cocoa mulch in other countries such as the United States and United Kingdom. As far as RSPCA Australia is aware cocoa mulch is generally not available in Australia however, it is possible that some small domestic chocolate manufacturers could sell cocoa shell mulch as a waste product from their chocolate manufacturing process. Therefore, while it is unlikely, it is still possible that a dog could have access to cocoa shell mulch in the Australian context.
All parts of the cocoa bean contain "theobromine", a methylxanthine compound that has similar properties to caffeine and is toxic to dogs and other pets at certain doses. It is this chemical that is the cause of chocolate poisoning, a problem that occurs mainly in pet dogs but also occurs occasionally in pet cats or other pet animals.
The level of theobromine varies with the type of chocolate; baking chocolate and dark chocolate contain the most theobromine. Cocoa bean shells may contain relatively high levels of theobromine, and some reports suggest that, for a medium-sized dog, consuming about 250 grams of mulch could be fatal.
The symptoms of theobromine ingestion vary with the dose consumed. At lower doses, the pet may develop gastrointestinal signs such as vomiting or diarrhea but should recover with supportive veterinary care. If the pet eats a toxic dose the symptoms are more serious involving muscle tremors, restlessness or hyperactivity, elevated heart rates, seizures and possibly death. Symptoms may not develop immediately, but will begin to appear as the toxin is absorbed into the body. Immediate veterinary attention is required.
Unfortunately the chocolate aroma of the mulch makes it a popular choice for gardeners and also highly attractive to pets as something to eat. It is also common for this mulch to develop a coating of mould as it decomposes; depending on the type of mould that develops and this may represent a further risk of mould toxicity to pets.
RSPCA Australia recommends that pet owners do not use any cocoa-containing mulch products.
Any persons using cocoa mulch should ensure that any animals in the area cannot gain access to the cocoa mulch. Please note that cocoa mulch is highly attractive to dogs due to the cocoa scent and flavour so pets may try to access the mulch for e.g. by jumping over fences around garden beds or by breaking open bags kept in sheds. Adequate precautions should be taken.
It is also important to note that there are generally no label warnings about the potential toxicity to pets on the packaging of cocoa mulch so owners may not be aware of the serious risk these products pose to their pets.
