By Kathy Adams Updated September 03, 2019
Preen's weed-killing product line contains a few ingredients that may be of concern if pets share your yard. While the formula for one Preen product varies from the next, some contain ingredients such as the common weed killer 2,4-D, which is potentially harmful to dogs, aquatic life and humans. Glyphosate, another potential toxin, is also in some Preen products.
Preen's Pre-Emergent Weed Treatments
Preen's most common products are pre-emergent weed treatments, designed for killing weeds that have not yet established themselves in flowerbeds and gardens. This type of product is not for use on lawns. The main chemical in products such as Preen Garden Weed Preventer is trifluralin, which can irritate eyes and skin. It is harmful to fish and other aquatic life as well, and it should not be used near waterways, ponds, storm sewers or even driveway drains.
Grass and Weed Killers
Preen's Grass and Weed Killer, designed for use between pavers and the like, contains the controversial chemical glyphosate. This chemical, a key component of Roundup, is suspected to cause health problems in humans. Glyphosate is widely used on crops as well, so many people are exposed to it either directly or indirectly via the foods they eat or handle.
Dogs are exposed to lawn chemicals far more often than humans, largely because they're closer to the ground. They may walk in treated areas or even eat plant matter coated with the chemical. Lawn chemicals such as glyphosate have been linked to increased occurrences of lymphoma in dogs.
To limit pet exposure to glyphosate, either do not use the chemical, or follow the package directions carefully and wait until the treated areas are completely dry before allowing pets to roam outdoors. Exercise caution when walking a dog along a street, as any neighboring lawn may have harmful chemicals on it. Avoid areas that are freshly treated.
Lawn Weed Treatment Dangers
The label on Preen's Lawn Weed Control product, which is used to kill existing weeds, notes that the substance is hazardous to humans and domestic animals, as well as to aquatic creatures. It contains the chemical dichlorophenoxyacetic acid, commonly called 2,4-D. This chemical can cause skin, eye and airway irritation, so be sure to wear a dust mask, full clothing coverage and eye protection when using the product.
Other people and pets should stay away from the treatment area as you apply the product. Dogs may be more sensitive to 2,4-D than other animals. A dog or cat that eats this substance may vomit, develop diarrhea or even have convulsions.
It's best to avoid using potentially harmful chemicals to treat the lawn, but if you decide to use such a product anyway, do not allow children or animals onto the treated area until after the lawn dries. Do not allow pets near any puddles that are developing after you've watered the lawn for treatment, as they may contain weed-killing chemicals. Be sure to sweep up any granules that get onto nearby pavement or bare dirt. Such products also aren't for use where water runoff may get into waterways, sewers, pond and storm drains, as aquatic life may be harmed by the chemicals.
No matter which type of Preen or weed-treatment product you're considering, read the package label, noting ingredients and safety concerns, before purchase. This helps ensure you're buying products that offer the least negative impact on people, wildlife and the environment as a whole.
