When deciding between food-grade diatomaceous earth (DE) and non-food-grade diatomaceous earth, it’s crucial to understand their differences, especially regarding safety and intended use. While both types come from the same natural mineral source — the fossilized remains of diatoms — their composition, processing, and applications are very different. Let’s break down these two types of DE to help you choose the right one for your needs.
What Is Diatomaceous Earth?
Diatomaceous Earth (DE) is a naturally occurring, soft, sedimentary rock that crumbles into a fine, white powder. This powder has many microscopic, sharp edges that make it useful in various applications, from pest control to filtration and even as a dietary supplement.
Types of Diatomaceous Earth
There are two primary types of diatomaceous earth:
1. Food-Grade Diatomaceous Earth
Food-grade diatomaceous earth is the purest form of DE, consisting of less than 1% crystalline silica. This type of DE is mined from freshwater sources, and it is not heat-treated or chemically altered, making it safe for consumption by humans and animals.
- Composition: Contains less than 1% crystalline silica; mostly amorphous silica, which is non-toxic.
- Uses:
- Pest Control: Effective against ants, fleas, bed bugs, cockroaches, and other crawling insects. It works by cutting through the exoskeleton of insects, causing them to dehydrate and die.
- Health Supplements: Some people use it as a natural detox, claiming benefits like improved digestion, healthier skin, and joint health.
- Pet Care: Can be mixed with pet food to help control internal parasites or dusted onto fur for flea control.
- Food Storage: Often added to stored grains and dry foods to prevent insect infestation.
- Safety: Safe for humans and pets when used as directed. However, inhaling large amounts can cause respiratory irritation, so it’s advisable to use a mask during application.
2. Non-Food-Grade Diatomaceous Earth (Filter-Grade)
Non-food-grade diatomaceous earth, also known as filter-grade or pool-grade DE, contains a high level of crystalline silica (more than 60%) and is heat-treated (calcined) to enhance its filtration properties. This form is highly effective in industrial applications, but it is not safe for use around humans or pets due to its toxic nature when inhaled or ingested.
- Composition: Contains more than 60% crystalline silica, which is toxic when inhaled.
- Uses:
- Water Filtration: Commonly used in pool filters, hot tubs, and industrial water filtration systems.
- Industrial Applications: Acts as a filler in paints, as an abrasive in polishes, and in other manufacturing processes.
- Safety: Not safe for humans or pets. Inhalation of crystalline silica dust can lead to silicosis, a serious lung disease. This type should never be used for pest control, food storage, or as a health supplement.
Key Differences Between Food-Grade and Non-Food-Grade Diatomaceous Earth
| Feature | Food-Grade Diatomaceous Earth | Non-Food-Grade (Filter-Grade) Diatomaceous Earth |
|---|---|---|
| Silica Content | Less than 1% crystalline silica | Over 60% crystalline silica |
| Processing | Not heat-treated, naturally occurring | Heat-treated (calcined) to enhance filtration |
| Safety for Humans and Pets | Safe for consumption and topical use (in moderation) | Not safe; can cause respiratory issues and silicosis |
| Common Uses | Pest control, health supplements, pet care, food storage | Pool filtration, industrial filtration, abrasives |
| Effectiveness in Pest Control | Highly effective and safe | Not used for pest control |
| Availability | Readily available in stores and online | Found in pool supply stores or industrial suppliers |
When to Use Food-Grade Diatomaceous Earth
Food-grade DE is the go-to choice for household and garden applications. Here are some common uses:
1. Pest Control in the Home and Garden
- Food-grade DE is highly effective for treating pests such as ants, fleas, bed bugs, and cockroaches. Simply sprinkle a fine layer around baseboards, in cracks and crevices, and anywhere pests are likely to travel. It is safe to use around pets and children, provided it is applied correctly and not inhaled.
2. Health Benefits for Humans and Pets
- Some people consume food-grade DE as a dietary supplement for its supposed health benefits, such as detoxification and improved digestion. Always consult a healthcare professional before taking DE as a supplement.
- For pets, DE can help with internal parasites like worms and external pests like fleas when added to food or dusted onto fur.
3. Food Storage
- To protect stored grains, beans, and other dry goods from insect infestation, a small amount of food-grade DE can be added to storage containers.
When to Use Non-Food-Grade (Filter-Grade) Diatomaceous Earth
Non-food-grade DE is strictly for industrial and filtration purposes:
1. Pool and Water Filtration
- This type of DE is perfect for filtering impurities from swimming pools, hot tubs, and even industrial water systems. It helps keep water clear by filtering out particles and bacteria.
2. Industrial Uses
- Filter-grade DE is used in a variety of industrial processes, including as a filler in paints, as an abrasive in polishes, and in insulation.
Safety Considerations
Food-Grade Diatomaceous Earth Safety
While food-grade DE is safe for consumption and topical use, it can still cause respiratory irritation if inhaled. Here are some safety tips:
- Wear a Mask: When applying DE, especially in dust-prone areas, wear a mask to prevent inhalation.
- Keep Out of Eyes: Avoid contact with eyes, as DE can cause dryness and irritation.
- Store Properly: Keep DE in a sealed container in a dry place to maintain its effectiveness.
Non-Food-Grade Diatomaceous Earth Safety
Non-food-grade DE is not safe for any use involving human or animal contact:
- Wear Protective Gear: When handling pool-grade DE, always wear a mask, gloves, and eye protection.
- Avoid Contact: Keep it away from pets and children and never use it for pest control or any food-related purpose.
- Dispose Carefully: Follow local guidelines for disposal to avoid environmental contamination.
Final Verdict: Choose Food-Grade DE for Safe Household Use
For any use around the home, garden, or with pets, food-grade diatomaceous earth is the only safe and recommended choice. It is versatile, non-toxic, and effective for a variety of purposes, from pest control to health supplements. On the other hand, non-food-grade DE is strictly for industrial applications and should never be used in any scenario involving humans or pets. Always read labels carefully and ensure you are using the appropriate type of DE for your specific needs.