Selective Herbicides

Selective Herbicides

The Animal Poisons Helpline has recently been contacted regarding several isolated cases of bromoxynil and MCPA poisoning in dogs. These chemicals are selective herbicides that can be sprayed onto lawn to kill weeds and are often co-formulated in one solution.

Once diluted and sprayed out, these herbicides are considered reasonably safe, however any pet that ingests these chemicals from the primary packaging (or from spilt volumes) can be at risk. The concentrated forms (those that need to be mixed with water or another solvent before being used) are highly toxic and can result in life-threatening poisoning from relatively small ingestions.

Signs of poisoning can include vomiting, panting at rest, and fever. If the herbicide is dissolved in a hydrocarbon solvent, the mouth may smell like petrol or kerosene. Whilst there is no antidote, early veterinary treatment of these cases can be lifesaving.
To keep your pet safe, ensure that herbicides and other chemicals are always stored out of reach. Keep your pet(s) away when measuring, diluting, and spraying herbicides and do not allow them to return to the treated area(s) until thoroughly dry. As a further safeguard, if you have pets consider not storing herbicide concentrates (products that need to be diluted prior to being sprayed) on your property at all.

If your pet has ingested something they should not have, please phone the Animal Poisons Helpline 1300 869 738 (AU) or 0800 869 738 (NZ) for advice. The Animal Poisons Helpline provides a free service for all pet owners in Australia and New Zealand, and we can rapidly determine if your pet requires immediate veterinary assessment or can be observed at home.

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This post has been made possible by a grant from Animal Welfare Victoria.