Dear Daisy Dog
My two Shetland sheepdog friends died of cancer when they were only six years old. Could weed killer on the lawn have made them sick? What about insecticides?
It’s possible that herbicides used on the lawn or in the garden contributed to their cancer, but it’s unlikely that insecticides did.
To test the possible role of herbicides and insecticides in cancer, researchers studied Scottish terriers, the breed at greatest risk of developing transitional cell carcinoma (TCC), the most common type of bladder cancer.
Bladder cancer is thought to develop after the lining of the bladder is exposed to cancer-causing toxins in the urine. Studying bladder cancer in a breed predisposed to it is a good way to evaluate potential carcinogens.
In one study, Scottish terriers exposed to lawns and gardens treated with phenoxy type herbicides had a higher incidence of TCC than Scotties whose properties weren’t chemically treated.
Non-phenoxy herbicides, such as Roundup, were not associated with cancer. In fact, even when dogs, rats and mice were fed huge doses of glyphosate, the active ingredient in Roundup, they did not develop cancer.
Scottish terriers exposed to lawns and gardens treated with insecticides – and Scotties medicated with Advantage or Frontline, both topical insecticides – experienced no increased risk of TCC.
My advice is to avoid lawn and garden chemicals. If you must use them, choose a non-phenoxy product, apply a minimal amount and make sure it’s dry before your pets walk on it.