yellow lab sits in yard with leaves

Toxic Lawn Chemicals: Is My Dog Safe?

Many of us look forward to gardening and maintaining a beautiful lawn when summertime gets here, but did you know that many chemicals that we spray or spread on our lawns to keep them weed-free and plush can be dangerous for our pets and for our families?

Contrary to what lawn ‘care’ companies would like people to believe, herbicides (weed killers) and other pesticides are not ‘magic bullets’. They are broad spectrum biocides, and by their very nature can harm organisms other than targeted species. This includes homeowners and their families, neighbors, pets, and all other forms of life. The pesticide industry downplays this by claiming their chemicals are heavily diluted, but doesn’t mention the toxins are still extremely dangerous in small amounts.

The Truth About Cats, Dogs & Lawn Chemicals

A dog and cat laying in the grass.This is some scary stuff! To find out just how dangerous these chemicals can be, researchers at Purdue University and the University of North Carolina measured the concentration of lawn chemicals in dog urine in a few different scenarios:

  • In households that treat their lawns with chemicals, these chemicals were found in the urine of dogs in 14 out of 25 households before their lawn treatment, and in 19 out of 25 households after their lawn treatment.
  • The lawn chemicals were also found in the urine of dogs in 4 out of 8 households that did not treat their lawns with chemicals.
  • In 2004, these same researchers from Purdue University found that when Scottish terriers were exposed to lawn chemicals, they were found to develop bladder cancer at a rate 4 to 7 times higher that Scottish terriers not exposed to lawn chemicals.
  • Additionally, “The US Center for Disease Control and Prevention (CDC), in a study of 9,282 people nationwide, found pesticides in 100% of the people who had both blood and urine tested. The average person carried 13 of 23 pesticides tested.” -Pesticide Watch

When and Why Did Americans Start Using Lawn Chemicals?

After World War II, and again after the Vietnam War, companies that made biological weapons for the American military decided to start marketing these same chemicals as pesticides and herbicides to spray on lawns, so that profits could continue to be made off of these chemicals. The marketing skill of these chemical companies is essentially the beginning of our American obsession with a beautiful, green lawn!

Additionally, pesticide use in agriculture, industry, commercial and government sectors has been decreasing over the past 20 years, but pesticide use in residential settings is rising. “Home use of pesticides has risen 42% between 1998 and 2001 and now represents the only growth sector of the U.S. pesticide market.” -Pesticide Watch, 2008

A yellow lab puppy near a pot of red flowers.

How Does Exposure Occur?

  • It is estimated that 70 to 80 million pounds of pesticides are sprayed on home lawns annually across the country. (Pesticide Watch)
  • Our pets are exposed to these lawn chemicals by either eating grass that has been treated, drinking from an outdoor water bowl that has been compromised, breathing in chemical-filled pellets when sniffing around the yard, or by having chemicals rub onto their bellies, legs, and paws when walking through a treated lawn, and then licking these same spots later.
  • Lawn chemicals can remain on our lawns for at least 48 hours after application. Specifically, the chemicals: 2,4-dichlorophenoxyacetic acid (2,4-D), 4-chloro-2-methylphenoxypropionic acid (MCPP), and dicamba are more likely to remain for longer.
  • Lawn chemicals can easily spread to untreated yards and pets from the yards of neighbors through run-off from water, being blown by the wind, or by walking our dogs near or on lawns with chemicals.
  • Our pets can then pass along chemical contamination to other pets, children or people in the home when we play with or pet them, or by simply lying on our floor or furniture.

A black and white great dane covered in dirt from breaking a flower pot.

Risks from Exposure

  • Elderly and sick pets are at a higher risk to be harmed by lawn chemicals.
  • Lawn chemicals have been shown to be associated with an increased risk of bladder cancer and other cancers, such as thyroid cancer and lymphomas.
  • Other dangerous symptoms and consequences of lawn chemical exposure include: vomiting, nausea, excessive salivation, stomach pain, diarrhea, low heart rate, dehydration, cramping, respiratory failure, convulsions, dizziness, twitching, loss of feeling, weakness, fatigue, dermatitis, hyperexcitability, depression, ataxia, anorexia, enlarged thyroid and liver, labored breathing, loss of consciousness, and in some cases, death.


  • Store any lawn chemicals safely away from pets (and children!)
  • Avoid treating your lawn with chemicals, and be wary of neighbors or parks that treat with chemicals.
  • If you must treat your yard, keep pets and all water bowls and toys inside during application, and make sure any chemicals have fully dried or absorbed before letting pets back outside
  • Wash dogs’ feet and bellies after any exposure to lawn chemicals
  • Specifically avoid products containing these chemicals: disulfotons, metaldehydes, organophosphates, carbamates, phenoxy and benzoic acid herbicides, and pyrethroids (possible carcinogens according to EPA).
  • “53% of TruGreen ChemLawn’s pesticide products include ingredients that are possible carcinogens, as defined by the United States Environmental Protection Agency. 41% of TruGreen ChemLawn’s pesticide products include ingredients that are banned or restricted in other countries.” (Pesticide Watch)

Forget Chemicals, Try This Instead

  • Adjust the acidity or alkalinity (pH) of your soil so that it is at the peak pH for grass to grow (which is around 6.5 or 7 on a scale from 0 to 14, or neutral). If your soil is too acidic, you will need to add lime. If your soil tests too high in alkalinity, you will need to add sulfur to get the right balance.
  • Don’t treat your backyard (where pets frequently roam) even if you treat the front yard.
  • Use organic, slow-release fertilizer to stimulate grass growth.
  • Overseed patchy areas of your lawn to encourage more grass to grow. This works best in the spring and fall.
  • Set your mower on high (3 inches) instead of cutting your lawn really low in order to crowd out any weeds.


Do you have any tips for maintaining a beautiful lawn without the use of chemicals? Has your dog or cat been affected by lawn chemicals? Share your tips and stories with us in the comment section below.


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