If your dog licked diatomaceous earth off the floor, the short answer is that almost none of the powder gets into your dog's body. The National Pesticide Information Center says the eaten portion is barely absorbed, and the rest keeps moving until you see it again in the stool. That is a different picture from a poison bait, which is built to be absorbed. Check the bag before you relax, though.
Our bag sits on a shelf in the detached garage, right above the mower. One morning I found the dog with her nose in a white smear on the concrete, muzzle dusted pale, tail swinging. I checked the label line by line before I did anything else. Some products sold as diatomaceous earth for pets carry directions for use right on dogs and cats. NPIC counts more than 150 registered products for buildings, farms, gardens and kennels.
The feeding data is calm, but thin. Almost nothing crosses from the gut into the blood, and what does not cross keeps going until your dog passes the rest. No study has measured a dog that got into an open bag, and no one has published a safe amount for a dog of any size. So the mouthful matters less to you than what was in the powder. Some products blend in other active ingredients, and the label is your only way to know.
The numbers you can lean on come from feeding trials. Rats fed a diet of 5% diatomaceous earth for 90 days showed a single effect, and that effect was faster weight gain. People who ate a few grams showed no change in the silicon dioxide in their urine, which fits the idea that the powder passes straight through. The FDA lists the material as Generally Recognized as Safe, and food grade powder goes into animal feed as an anticaking material. None of that gives you a dose for your dog. That is why the stuff shows up in feed at all.
Grade is the fork in the road for you. Food grade diatomaceous earth safety is one question. Pool or filter grade is another, because that powder carries crystalline silica. IARC puts crystalline silica breathed in at work in Group 1, known to cause cancer in people, while amorphous silica sits in Group 3. That ranking covers years of workplace dust, not one lick off your garage floor. Keep pool grade out of the yard and off any floor your dog walks on. The words pool grade or filter grade on the front of the bag are the flag you want to catch.
Breathing the powder is the other half of your answer. NPIC says the dust irritates the nose and nasal passages, and very large amounts can bring on coughing and shortness of breath. So sweep the loose pile up rather than let your dog keep snuffling at the spill. Open a door before you brush the dust off your dog's coat, and do the brushing outside if the weather lets you.
Call your vet, or an animal poison control service, any time the grade is unclear, the label names other active ingredients, or your dog seems off. Take the bag with you, or at least a photo of the whole label. Say what your dog licked, roughly how much you saw, and how long ago. Do not work out a safe amount on your own, because none has been published. If the bag says food grade and your dog is eating, drinking and acting normal, keep watching and call if anything changes.
Read the full article: Diatomaceous Earth: What It Really Kills
