Studies Find Links Between Dog Cancers and Lawn Chemicals

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6.8.17 Lawn Chemicals Linked to Dog Cancer1



Because herbicides are created with the intent to kill, it should come as no surprise that new studies have linked them – particularly the ones that contain 2,4-D (one of the main ingredients in Agent Orange – to at least two kinds of cancer in dogs.  Even dogs whose lawns haven’t been treated have been found with the toxic chemicals in their bodies.

Spraying lawns with herbicides and pesticides may rid them of what people believe to be “pests,” but slugs and bugs have their place on this planet, too.  Rodents and birds eat the grubs, which are then in turn sometimes consumed by neighborhood cats and dogs, so the poisons affect much more than their intended targets.  Even if pets don’t eat outdoor critters, they and people can track pesticides in with them.

There have been numerous studies on 2,4-D (2,4-Dichlorophenoxyacetic acid) showing the detrimental effects on many forms of life.  It’s an endocrine-disrupting chemical, meaning that it mimics or inhibits the body’s hormones, specifically targeting the thyroid.  It can also decrease fertility and raise the risks of birth defects.

This toxin is used as more than just a dandelion and clover killer; it’s also used on cereal crops, orchards, and pastures.  It has made its way into the groundwater and drinking water in many places, and runoff from large farms is killing aquatic life.

Tufts University School of Veterinary Medicine conducted a six-year study and found that the use of lawn pesticides was associated with a greater risk of canine malignant lymphoma (CML), a model for non-Hodgkin’s lymphoma (NHL) in humans.


6.8.17 Lawn Chemicals Linked to Dog Cancer2


“Specifically, the use of professionally applied pesticides was associated with a significant 70% higher risk of CML,” the authors stated.  “Risk was also higher in those reporting use of self-applied insect growth regulators.”

An earlier study showed that herbicides with 2,4-D doubled the risk of CML when owners sprayed their lawns four or more times in a year.

A study from 2013 demonstrated that the risk of dogs developing bladder cancer was “significantly higher” following the use of 2,4-D herbicides.  Some breed of dogs, such as Beagles, Scottish Terriers, Shetland Sheepdogs, West Highland White Terriers, and Wire Hair Fox Terriers, have a genetic predisposition to bladder cancer, and are likely even more susceptible to developing it when exposed to lawn chemicals.

“Chemicals were detected in the urine of dogs in 14 of 25 households before lawn treatment, in 19 of 25 households after lawn treatment, and in 4 of 8 untreated households,” the study concluded.  “Chemicals were commonly detected in grass residues from treated lawns, and from untreated lawns suggesting chemical drift from nearby treated areas.”

It would be wise to keep far away from any lawns that have been treated with toxic chemicals.  Parents and dog owners may want to consider asking their municipalities if pesticides or herbicides are used in their local parks.  For more information, visit the National Pesticide Information Center.