What are the side effects of diatomaceous earth?

December 20, 2025 •

2 min read

According to the National Pesticide Information Center (NPIC), inhaling diatomaceous earth (DE) dust can irritate the nose, nasal passages, and lungs, with more serious risks depending on the type of DE. While often lauded for natural applications like pest control, understanding the potential side effects is crucial for safe handling.

Quick Summary

Diatomaceous earth carries risks of respiratory, skin, and eye irritation, with severity depending on the product's grade and proper handling. The most significant danger is inhalation of crystalline silica found in filter-grade DE, which can cause permanent lung damage.

Key Points

Inhalation is the primary risk: Breathing in DE dust can cause respiratory irritation, coughing, and shortness of breath for both humans and pets.
Food-grade vs. filter-grade matters: Filter-grade DE contains dangerously high levels of crystalline silica and should never be inhaled, ingested, or used for pest control.
Crystalline silica causes silicosis: Prolonged exposure to crystalline silica from filter-grade DE can lead to silicosis, a permanent lung-scarring disease.
DE causes skin and eye irritation: The abrasive nature of DE can cause dryness and irritation to skin and eyes upon contact.
Take safety precautions: Always wear protective gear, including a mask, goggles, and gloves, when handling DE, even the food-grade version.
Use in well-ventilated areas: Minimize dust by applying DE sparingly in well-ventilated spaces and cleaning with a HEPA filter vacuum.

Understanding the Different Grades of Diatomaceous Earth

Food-grade DE contains low levels of crystalline silica (under 2%), while filter-grade DE, which is heat-treated, has high levels (around 60%). Filter-grade DE is toxic and used industrially, like for pool filtration. Only certified food-grade DE is recommended for home and pet use.

Inhalation Risks and Respiratory Side Effects

All powdered DE poses an inhalation risk.

Short-Term Inhalation Effects

Nasal and Throat Irritation: Coughing and irritation can occur.
Shortness of Breath: Inhaling large amounts can cause coughing and breathlessness.

The Dangers of Crystalline Silica and Silicosis

Handling filter-grade DE or consistent high exposure to crystalline silica presents severe risks.

Silicosis: Prolonged inhalation of crystalline silica dust can cause this severe, chronic lung disease, leading to scarring and breathing issues.
Lung Damage: Chronic exposure is linked to increased risks of other respiratory diseases and potentially lung cancer.

Skin and Eye Irritation

DE's abrasive nature can affect skin and eyes.

Skin Dryness and Irritation: Direct contact can dry out skin and cause irritation.
Eye Irritation: If DE enters the eyes, it can cause significant irritation. Rinse immediately with water.

Effects on Pets and Animals

Using food-grade DE on pets requires caution.

Respiratory Issues: Pets can experience respiratory irritation from inhaling the dust.
Digestive Upset: Ingesting DE while grooming may cause temporary mild diarrhea or constipation.
Skin and Eye Irritation: Direct application can cause dryness and irritation. Avoid eyes.

Safe Handling and Application

Proper handling minimizes risks.

Wear Protective Equipment: Use gloves, goggles, and a dust mask or respirator when applying DE.
Apply Sparingly: A light dusting is effective and creates less airborne dust.
Use in Well-Ventilated Areas: Ensure good ventilation indoors.
Keep Dry: DE is less effective when wet.
Clean Up Correctly: Use a HEPA filter vacuum or damp rag for indoor cleanup.

Comparison of Diatomaceous Earth Grades


Feature	Food-Grade Diatomaceous Earth	Filter-Grade Diatomaceous Earth
Processing	Minimally processed	Heat-treated (calcined)
Crystalline Silica Content	Less than 2%	Approximately 60% or higher
Inhalation Risk	Lower risk of serious disease, but still causes respiratory irritation	Significant risk of silicosis from inhalation
Consumption Safety	Generally recognized as safe by the FDA	Extremely toxic, never for consumption
Primary Use	Pest control, anti-caking agent, supplement	Industrial filtration, fillers
Appearance	Fine, white powder	Off-white powder, may be coarser

Conclusion: Prioritizing Safety When Using Diatomaceous Earth

Side effects of DE depend on the type and handling. Food-grade DE is low-toxicity, but inhalation risk is present. Serious effects like silicosis are linked to crystalline silica in industrial grades. Always confirm the grade, wear protection, and apply safely in ventilated areas.

For more information on handling risks, refer to the National Pesticide Information Center Diatomaceous Earth Fact Sheet.

Frequently Asked Questions

Accidentally inhaling food-grade DE can cause temporary irritation to the nose, nasal passages, and lungs, which may result in coughing and shortness of breath. For most healthy individuals, this is a minor, reversible effect, but repeated exposure should be avoided.

The FDA lists food-grade diatomaceous earth as "Generally Recognized as Safe" (GRAS) for consumption. It passes through the digestive system largely unchanged and does not enter the bloodstream. However, it's not a regulated dietary supplement, and reliable scientific evidence for its purported health benefits is limited.

The main difference is the crystalline silica content. Food-grade DE has less than 2% crystalline silica, while filter-grade DE contains around 60% due to high-heat treatment. Filter-grade DE is hazardous to inhale and not safe for consumption, unlike the food-grade version.

Yes, due to its abrasive and drying nature, contact with diatomaceous earth can cause skin dryness and irritation. It's best to wear gloves when handling the powder to avoid skin issues.

If DE gets in your eyes, it can cause irritation. Immediately rinse your eyes with a gentle stream of water for several minutes. If irritation persists, seek medical attention.

Food-grade diatomaceous earth is generally considered safe for use around pets when applied carefully. However, pet owners should still take precautions to avoid inhalation and skin/eye contact, as it can cause irritation. Use it in well-ventilated areas and in places where pets cannot easily disturb or track it.

Silicosis, a severe lung disease, is a risk associated with inhaling high levels of crystalline silica. While food-grade DE has very low levels, filter-grade DE contains high concentrations, and inhaling it can cause silicosis with prolonged exposure.

When applying DE, wear a mask, gloves, and goggles to prevent inhalation and skin/eye irritation. Use a thin layer of dust in well-ventilated areas and clean up any excess with a HEPA filter vacuum or damp cloth.