Diatomaceous Earth and Chickens: Why I Changed My Mind After Years of Using and Recommending It
Food-Grade Diatomaceous Earth (DE)
Diatomaceous earth is a natural product, often sold at garden centers to control ants. It consists of geological deposits of the fossilized remains of diatoms, microscopic single-celled algae. Once ground, it resembles talcum powder. It was once widely believed to be harmless to people and animals when used properly. However, this product creates dust that can be harmful to the respiratory system. I no longer recommend adding it to chickens’ dust baths. Sand and loose soil are better choices, and some keepers also use wood ash. Chickens shaking dust out of their feathers should not be breathing airborne DE. Some backyard chicken experts have stopped recommending DE entirely because it is so frequently misused.
However, different grades and compositions of diatomaceous earth exist.
So-called food-grade diatomaceous earth consists primarily of amorphous silica, but it may also contain some crystalline silica.
Calcined diatomaceous earth, used in certain industrial filtration processes, may contain much higher levels of crystalline silica.
This distinction matters because different forms of silica do not have identical health effects.
Importantly, “food grade” does not mean that a product is safe to inhale.
A product approved for a specific food-related use is not automatically appropriate for dispersal into the air inside a chicken coop.
Why Have I Changed My Mind About Diatomaceous Earth?
When I founded Poules en Ville in 2015, diatomaceous earth was already commonly recommended among backyard chicken keepers.
People attributed many benefits to it: killing lice and mites, preventing parasite infestations, drying out bedding, reducing odors, and even helping eliminate intestinal worms.
Like many people interested in natural animal care, I explored this product and its uses.
But over time, my reading, research, and experience helping chicken keepers led me to question some of those recommendations.
Just because a product is natural does not mean it is necessarily safe. And just because a practice is popular does not mean it is scientifically justified.
Today, I believe the potential benefits of DE do not justify routinely using it in chickens’ surroundings, particularly when they may inhale it repeatedly.
I therefore prefer prevention and care methods that limit birds’ exposure to fine dust.
For centuries, people in developing countries have protected stored grain against insect damage by adding natural substances. Commonly used materials have included plant ash, lime, dolomite, and diatomaceous earth.
With the introduction of chemical pesticides in the 1940s, another solution to insect pests appeared to have been found. These products brought considerable benefits, but their associated problems are now well recognized, including insect resistance, environmental pollution, contamination of food, and health risks during handling. This has prompted researchers to take another look at mineral and other natural powders as protective agents and explore ways to improve their performance.
The Main Concern: Respiratory Health Risks
Chickens have a highly specialized respiratory system, with relatively rigid lungs and air sacs that enable efficient airflow.
This system meets their high oxygen needs but also makes air quality especially important.
Inside a chicken coop, dust can come from feathers, skin flakes, feed, dried droppings, and bedding materials.
Deliberately adding a very fine mineral powder introduces another potential source of inhalable particles.
When a chicken scratches the ground, flaps its wings, or takes a dust bath, particles can become airborne again.
What Does Scientific Research Tell Us?
The respiratory effects of silica depend on its form, particle size, airborne concentration, and duration of exposure.
Long-term inhalation of respirable crystalline silica is a well-established hazard to human health. It is associated with silicosis, certain chronic lung diseases, and lung cancer.
Amorphous silica generally has a different, less concerning toxicological profile, but its dust can still irritate the respiratory tract.
Scientific data on the effects of chronic DE exposure in chickens remain more limited than the human evidence.
It would therefore be an exaggeration to claim that every use of DE automatically causes lung disease in chickens.
However, a lack of complete evidence of harm at every exposure level is not proof of safety.
Why add fine dust to an animal’s breathing environment every day when it can be avoided?
This is now one of the main reasons I have changed my position.
Diatomaceous Earth Can Also Dry Out and Irritate Tissues
DE works in part through its absorbent and abrasive properties.
In certain insects, it damages the protective outer layer of the exoskeleton, encouraging dehydration.
This mechanism explains its use as a physical insecticide.
But the powder’s drying properties also raise concerns when it repeatedly comes into contact with animals’ skin, eyes, and mucous membranes.
Direct exposure may cause dryness or irritation, especially when large amounts are applied.
Chickens also have a uropygial, or preen, gland that produces secretions they spread over their feathers while preening. This behavior helps maintain their plumage.
It makes sense to avoid excessive application of drying substances to birds’ bodies.
However, claims that DE systematically destroys protective microbial populations on mucous membranes or suppresses chickens’ immune defenses have not been adequately demonstrated.
We need to distinguish known irritant effects from biological consequences that still require study.
Does It Really Work Against Lice and Mites?
DE does have insecticidal activity under certain conditions.
It would be inaccurate to say it never works.
Its effectiveness depends on several factors, including formulation, quantity, humidity, environmental conditions, and the parasite being targeted.
In damp conditions, its effectiveness may be lost.
Some studies have demonstrated reduced mite populations following treatments with DE.
However, that does not mean it is necessary or desirable to scatter it continuously in nest boxes, bedding, or dust baths.
Preventing Parasites Does Not Mean Constantly Treating Chickens
For a small backyard flock, prevention begins with good management of the birds’ living environment.
Chickens should be inspected regularly, especially under the wings, around the vent, and at the base of their feathers.
For preventive care, consider essential-oil-based products such as Chick’N Protect and Chick’N Feather Glo, used according to their respective directions.
Perches, cracks, and other places where mites can hide should also be checked. The article recommends spraying Chick’N Protect and Chick’N Feather Glo in these areas as a safer alternative to dispersing DE dust.
The poultry red mite, for example, spends much of its time in the environment rather than on the chicken.
An infestation therefore calls for an intervention suited to the parasite identified, not simply another dusting of powder inside the coop.
My recommendation: avoid routine insecticide treatments when no infestation has been identified.
Is Diatomaceous Earth a Dewormer?
My answer is NO.
This is probably one of the uses that most deserves to be questioned.
For years, some chicken keepers have added DE to feed in the hope of preventing or eliminating intestinal worms.
The usual claim is that its abrasive particles damage parasites. But once DE becomes wet inside the digestive tract, that proposed mechanism does not work in the same way as it does in dry conditions.
Should It Be Added to Bedding to Absorb Moisture and Eliminate Odors?
DE is sometimes recommended as a bedding additive to absorb moisture and reduce odors.
Yet when bedding gives off a strong ammonia smell, simply adding powder does not solve the problem.
Ammonia is produced in part by the breakdown of nitrogen-containing compounds in droppings, a process influenced by moisture and bedding conditions.
DE is not a reliable way to chemically neutralize ammonia.
A well-maintained coop should have relatively dry bedding, adequate ventilation, and an appropriate stocking density.
If you notice an ammonia odor, look for the cause: accumulated droppings, water leaks, a leaking drinker, inadequate ventilation, or unsuitable bedding.
Adding DE mainly risks introducing more dust without addressing the underlying problem.
Dust Baths: A Natural Behavior Worth Protecting
Chickens love dust bathing.
They scratch the ground, lie on their sides, spread their wings, and work fine particles through their feathers.
This natural behavior helps maintain their plumage and may reduce certain external parasites.
But there is no need to add DE for chickens to enjoy a good dust bath.
An area with loose, relatively dry, uncontaminated soil is generally ideal.
It is best to shelter the area from rain while maintaining good airflow.
Avoid deliberately adding extremely fine powders that unnecessarily increase respiratory exposure.
A natural dust bath does not need to become an insecticide bath.
What Are Better Options Today?
Over the years, I have gradually shifted toward a more comprehensive approach to chicken health.
Instead of looking for one product to solve every problem, I favor a combination of good practices. Choosing safe, suitable products specifically designed for chickens is a wiser approach.
A Healthy Living Environment
A clean, dry, well-ventilated, properly designed coop is the first line of prevention.
Choosing appropriate bedding—such as wood shavings and Nature Sorb for the outdoor run—is essential, along with nest-box maintenance, moisture control, and regular cleaning of perches. See my article comparing different bedding materials.
Regular Parasite Checks
Inspecting chickens helps detect early signs of an infestation before it becomes serious. See my article on how to examine a chicken or watch my online training course.
When parasites are present, identify the species and choose an appropriate intervention.
More Targeted Care Products
This philosophy also informs the development of the Chick’N Swell product line.
Chick’N Protect and Feather Glo are among the products we offer to support chicken care and maintenance, each according to its intended use.
The goal is not to replace one powder with another product applied automatically, but to choose targeted interventions suited to the birds’ actual needs.
Always follow the directions for use, and do not confuse supportive care with treatment for a parasite infestation that requires veterinary attention.
Why I No Longer Recommend Routine Use of Diatomaceous Earth
After all these years, my conclusion is simple.
DE has some useful properties and demonstrated effectiveness against certain arthropods under particular conditions.
However, that does not necessarily justify repeated use in chickens’ immediate surroundings.
The risks associated with inhaling dust, possible irritation, variable effectiveness depending on the application, and the availability of other management methods have led me to favor different approaches.
I am not saying that everyone who has used DE has harmed their chickens. Nor am I claiming that occasional exposure necessarily causes serious consequences.
But I do believe it is better not to add unnecessary sources of dust to an environment where birds breathe, sleep, and live every day.
Changing Your Mind Is Part of Learning
Since founding Poules en Ville, I have always wanted to share information that helps chicken keepers better understand their birds and provide them with good living conditions.
Over the years, some of my recommendations have changed.
And I believe that is a good thing.
We must be willing to revisit our practices when experience, scientific research, and new knowledge lead us to think differently.
Today, I have decided to stop using DE for routine chicken care, and I no longer recommend its regular use in coops or dust baths.
Because caring for our chickens also means being willing to question established habits, even when they have been around for years.
Poules en Ville — Helping people better understand the behavior, health, and well-being of backyard chickens.
ADD can be used as a first treatment, but if the parasites come back, always have on hand a product containing an insecticide against parasites prescribed by your veterinarian if your hens are affected by lice or mites. Otherwise, they will keep coming back.
Diatomaceous earth powder is an interesting ingredient to have on hand, because here are all the uses and advantages:
Sprinkle from time to time on the feathers of chickens; beware of the respiratory system of chickens!
Added in small quantities (5% of the ration) in the feed, it adds minerals. Although composed of nearly 85% of mineral silica (SiO2), about fifteen trace elements and minerals are naturally present in the composition of Diatomaceous Earth, including: boron, manganese, titanium, copper, sodium zirconium, magnesium and calcium …
When ADD is wet, it does not work against intestinal worms.
Among the other benefits of its use, TD can be sprinkled on animals, their bedding and niche to prevent external parasites. In the future, improvements in formulation should undoubtedly increase its use, while countering its disadvantages. Currently, it is probably the safest and most effective insecticide in the home. “Its use guarantees a better quality of life for its users and promotes the maintenance of a stable environment, relative to its pro-ecological properties.
Diatomaceous earth has the disadvantage of not being selective, i.e. it causes the death of all species of insects, whether beneficial or harmful. It must then be used with
The most effective natural powder is probably diatomaceous earth. This is a geological repository of fossilized skeletons of marine organisms (family of algae/unicellular plants). When crushed it has the appearance of talcum powder, but its texture, although harmless to humans and animals, has the effect of small crushed glass crystals on the insect; these are either ingested by the insect or are collected by its hairs (bristles), and adhere to its body to scrape through its tiny layers of protective wax, thus promoting a loss of liquid that results in dehydration and death of the insect. In addition, the absorbent properties of diatomaceous earth promote this process.
Today, during its formulation, a bait is incorporated into the diatomaceous earth, which attracts the insect and encourages it to pass through. Without it, it has a repulsive property and was once added in large quantities to the grain to protect it from pests. But these large quantities (3 1/2 kg/tonne) tended to make the grain heavier and very dusty.
At home, TD can be used to prevent the entry of certain insects, such as ants, cockroaches, earwigs and silverfish, as well as to control these and other insects in cabinets, carpets, basements, attics, window sills, etc. In all these examples, it is important to place a small amount of powder in corners, cracks, crevices and other areas where insects may be found.
While with a chemical pesticide the insect dies suddenly, insect control can take several days with diatomaceous earth. The most important difference, however, is that diatomaceous earth provides long-term protection of treated areas, unlike chemical pesticides.
Research Summary and References
- Schollmeyer et al. (2025) — Effect of Inert Dust Use on the Prevalence of Pulmonary Silicosis in Laying Hens. Avian Diseases, 69(4), 347–354. Researchers compared lung samples from 112 hens on two farms, one of which used amorphous-silica-based inert dust to control mites.
- Bennett et al. (2011) — Effects of DE on parasites and egg production.
- National Pesticide Information Center — DE composition, toxicity, and exposure risks.
- NPIC: Diatomaceous Earth FAQ — Why food-grade status does not establish safety for pesticide use.
Other studies summarized in the original article reported that:
- DE did not reduce parasite burdens as measured by fecal egg counts in the sheep and goat research cited.
- DE did not reduce anemia as measured by packed cell volume and other blood parameters.
Despite widespread interest in DE as a natural anthelmintic, relatively few studies have directly evaluated its effectiveness. Further research is needed.
Gail Damerow Was Already Warning Against Diatomaceous Earth
Gail Damerow, an American author known for her books on raising and caring for chickens, has expressed important reservations about using DE.
In The Chicken Encyclopedia, she advises against adding DE, wood ashes, or lime-and-sulfur garden powders to chickens’ dust baths because of respiratory risks.
She suggests that in cases of serious parasite infestation, the potential benefits might exceptionally justify temporary use. The word temporary matters: she does not recommend making it an everyday practice.
In The Chicken Health Handbook, second edition (2015), page 158, she explains that certain respirable particles can adhere to lung tissue and cause damage that impairs breathing.
She specifically discusses how inhaled DE particles may contribute to scar tissue formation in the lungs.
This warning is particularly relevant given birds’ specialized respiratory systems and their repeated exposure to dust in coops.
Damerow also questions the proposed mechanism by which DE supposedly works against intestinal parasites.
She explains that contact with saliva and digestive fluids changes the powder’s physical properties, casting doubt on the idea that it can eliminate worms simply by cutting or dehydrating them.
That explanation does not, on its own, prove DE is ineffective, but it reminds us that an insecticidal property observed under dry conditions cannot automatically be assumed to work inside the digestive tract.
These warnings, published years ago, show that questioning DE is not a passing trend. It is part of a longstanding discussion about poultry respiratory health and the importance of demonstrating the actual effectiveness of products we give our birds.
Further reading: The Chicken Chick — The Cut & Dry Truth About Diatomaceous Earth · Sheep and Goat — Diatomaceous Earth
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