GUILFORD COUNTY, N.C. – Summer temperatures mean pets might be spending some more time outdoors. But with all the rain we’ve had in May, for many homeowners – lawn care might be in order.

There’s some debate on the internet over what chemicals are consider “safe” or “unsafe” for dogs and cats. A few studies over the past years shown links between lawn chemicals using 2,4-D to two types of canine cancers. The World Health Organization’s International Agency for Research on Cancer classified 2,4-D as “possibly carcinogenic to humans…based on inadequate evidence in humans and limited evidence in experimental animals.”

However, experts say a link doesn’t always mean a strong connection. For pesticide application, per the North Carolina Department of Agriculture, licensure is required for anyone hoping to get paid for applying general and restricted-use pesticides. Licensure requires passing a core exam, and exams specific to what an applicator may be spraying – a farm, a commercial property, or a landscaped yard, for example.

The state’s Department of Agriculture stresses the studies and tests chemicals go through before being put on the market for use. Each chemical must go through short-term and long-term toxicity studies with rats and mice – to see what happens when intentionally high levels pass through the skin, the eyes, or being inhaled or ingested. From there, agencies determine what level to regulate on – and write labels accordingly.

Experts with the pesticides division say, when people get licenses to spray and use the chemical, they hammer home this: follow the label, the label is the law. Labels tell applicators how frequently to apply a chemical safely, as well as how much and other environmental precautions.

The National Pesticide Information Center reports 2,4-D is a herbicide that kills plants by changing the way certain cells grow. It comes in several forms, and depending on what form it is in determines its toxicity.

When it comes to sprays lawn care companies will use to treat yards, many contain 2,4-D. However, if pet owners follow the specific instructions, and wait until the chemical has set and dried, lawn care professionals and veterinarians say the effects on animals are minimal.

“Something like 2,4-D, there are no studies that show a direct link to causing cancer. You know, lettuce can cause cancer, if you eat too much of it believe it or not – anything in excess can be a carcinogen,” said Dr. Janine Oliver, “The big categories for lawn insecticides would be organophosphates and carbomates. Both of those are toxic to cats and dogs – and they’re toxic to people too but most people understand they shouldn’t put that stuff in their mouth.”

Dr. Oliver says the key for lawn safety, especially in the summer, is knowing your pet and their habits. For example, if they are grass-eaters – keep them out of treated areas. If you’re having your yard treated and worry about exposure, treat your lawn by other means – things like boric acid or essential oils. She also warns pet owners of other summertime hazards: animals like copperheads, hornets, and toads and plants and organisms like lilies, mushrooms, poison ivy and poison oak.