Searching through my gardening archive (it's heavy raining today) I just found this article that I had bookmarked a while ago:
PET DOGS GET CANCER FROM WEED KILLERS
Pet dogs exposed to the weed killer 2,4-D are dying of cancer at twice normal rates, according to a study published in the JOURNAL OF THE NATIONAL CANCER INSTITUTE.
Dog owners who spray or dust their lawns with weed killers containing 2,4-D are doubling Fido's chances of getting cancer, the study shows. Dogs walk across, or roll in, herbicide-treated lawns and then ingest toxic chemicals when they lick their coats or paws.
Popular lawn-care products containing 2,4-D include Weedone, Weed-B-Gone, and many others. Naturally, children!!! who play on treated lawns will also come in contact with the chemical.
Dogs and children can also track the chemical indoors where prolonged exposure to adult humans may occur.