Diatomaceous earth (DE) is made of the fossilized remains of tiny, aquatic organisms called diatoms. These diatoms’ skeletons are made of silica. Diatomaceous earth is used in a variety of applications, from insecticide to filtration aid, and even as a mild abrasive.
But is diatomaceous earth antifungal? Does this readily available substance have the power to kill or inhibit the growth of fungi? While DE is well-known as a natural insecticide, its potential as an antifungal agent is less clear.
This article will delve into the science behind diatomaceous earth and its potential antifungal properties. We’ll cover:
- What diatomaceous earth is and the different types available.
- How DE might affect fungi at a microscopic level.
- What research (if any) has been conducted on DE’s antifungal effects.
- How to use DE safely, including potential risks to consider.
Let’s explore the world of diatomaceous earth and its potential to combat fungal growth.
What is Diatomaceous Earth?
Diatomaceous earth (DE) is a naturally occurring substance made from the fossilized remains of diatoms, a type of hard-shelled algae. Under a microscope, DE looks like a collection of tiny, hollow tubes or cylinders.
Composition and Origin
Diatoms have been around for millions of years, and their fossilized remains are found in large deposits around the world. Diatomaceous earth is primarily made of silica (silicon dioxide), typically more than 80%. Silica is one of the most abundant elements on earth.
DE also contains trace amounts of other minerals.
Types of Diatomaceous Earth
There are two main types of diatomaceous earth:
- Food-grade DE: This type is safe for human and animal consumption in small amounts.
- Filter-grade DE: This type is not safe for consumption. It’s used in various industrial applications, such as filtering water and other liquids.
Key Properties
Diatomaceous earth has a few key properties that make it useful for a variety of purposes:
- Abrasive: The sharp edges of the diatom fossils make DE abrasive.
- Absorbent: DE is highly porous and has a high absorbent capacity.
How Diatomaceous Earth Works: Insecticidal vs. Antifungal Mechanisms
Diatomaceous earth (DE) has been registered for use as a pesticide since 1960, but does it fight fungus, too? Here’s how DE works, and what the science says about its potential as an antifungal agent.
Insecticidal Action
DE is effective against insects because of its physical properties, which include:
Physical Damage
DE works as a pesticide because it damages the exoskeletons of insects. The sharp edges of the diatoms that make up DE scratch and wear away the waxy coating on an insect’s body, leading to dehydration.
Desiccation
DE is highly absorbent, and this quality helps it to kill insects by drawing moisture from their bodies, leading to death.
Potential Antifungal Mechanisms (Hypothetical)
Scientists have proposed that diatomaceous earth may have antifungal properties, too. Here are some of the ways it may work against fungus:
Abrasive Action on Fungal Cell Walls
Like the exoskeletons of insects, the cell walls of fungi may be susceptible to damage from the abrasive nature of DE. By damaging the cell wall, DE may disrupt the cell’s integrity and lead to its death.
Desiccation of Fungal Spores
DE’s absorbent properties may also draw moisture from fungal spores, inhibiting their ability to germinate and grow. This would be most effective in dry environments.
Alteration of Soil/Surface pH
DE may slightly alter the pH of the surrounding environment, potentially inhibiting the growth of certain fungi.
Diatomaceous Earth and Fungi: What the Research Says
You’ll find a lot of anecdotal information about diatomaceous earth (DE) as an antifungal. But what does the research show?
Not much direct research
There hasn’t been a lot of scientific research specifically looking at whether DE is an effective antifungal. Most studies focus on how well DE works as an insecticide or on some other use.
Because DE is so effective at killing insects, it’s tempting to think it would also work on fungi. But insect exoskeletons and fungal cell walls are very different structures, so we can’t assume that what works on insects will also work on fungi.
Studies on soil-borne fungi
Some studies have looked at how DE affects soil health and the communities of microbes that live in the soil. These studies may indirectly show whether DE affects fungal pathogens.
For example, DE might change the populations of helpful microbes in the soil, and these changes might then affect fungal diseases in plants.
A few preliminary studies suggest that DE may be effective against certain plant fungal diseases, such as root rot, damping-off, and powdery mildew, but for a broader spectrum solution, one might consider options like chlorhexidine for fungus.
In vitro studies
In vitro studies are those done in a lab setting, rather than in the real world. Some in vitro studies have directly applied DE to fungal cultures to see if it inhibits their growth or damages their cells.
However, in vitro studies have their limits. The real world is much more complex than a lab setting. Soil composition, moisture levels, and the presence of other microorganisms can all affect how well DE works.
Practical applications and considerations
If you’re considering using diatomaceous earth as an antifungal, here are some things to keep in mind.
Using diatomaceous earth as an antifungal agent
Remember to use only food-grade diatomaceous earth. You can dust it onto plants or mix it into the soil. DE may be best suited for gardens, greenhouses, and homes. Avoid using it in sensitive areas where it could harm helpful organisms.
Safety precautions
DE can be irritating, so take precautions when you use it. For example, wear a dust mask to avoid inhaling DE dust, which can irritate your lungs.
Protect your skin and eyes by wearing long sleeves, long pants, and eye protection. DE can be abrasive and irritating.
It’s essential to use only food-grade DE when there’s a chance it could come into contact with humans or animals. Filter-grade DE contains crystalline silica, which is harmful if inhaled.
Limitations and alternatives
Environmental conditions, such as humidity and rainfall, can limit how well DE works.
Consider using DE as part of an integrated pest management (IPM) strategy, combining multiple methods to control pests and diseases sustainably, but for specific conditions such as fungal acne, salicylic acid or other targeted treatments may be needed. Talk to a gardening professional to learn more about IPM.
Frequently Asked Questions
What is the strongest natural antifungal?
There isn’t a single “strongest” natural antifungal, as effectiveness varies depending on the specific fungus and individual; for instance, the efficacy of coconut oil for toenail fungus can vary. Some commonly used and researched options include tea tree oil, oregano oil, garlic, and apple cider vinegar. Always dilute essential oils and consult a healthcare professional before using them, especially for internal use.
Can I rub diatomaceous earth on my skin?
Food-grade diatomaceous earth is generally considered safe to use on the skin in small amounts. However, it can be drying and irritating, especially for sensitive skin. It’s best to test a small area first and avoid prolonged or repeated use. Avoid getting it in your eyes or inhaling the dust.
Is it safe to sleep in a room with diatomaceous earth?
Sleeping in a room with diatomaceous earth can be safe if used properly. Ensure it’s food-grade and the dust has settled. However, prolonged exposure to airborne diatomaceous earth can irritate the lungs, so proper ventilation is key. Consider alternatives if you have respiratory sensitivities.
How do you flush out a fungal infection?
You can’t really “flush out” a fungal infection like you would with a physical object. Treatment typically involves antifungal medications (oral or topical) prescribed by a doctor. Supporting your immune system through diet, hydration, and stress management can also aid in recovery.
Do I need to wear a mask when using diatomaceous earth?
Yes, it’s highly recommended to wear a dust mask or respirator when applying diatomaceous earth, especially in enclosed spaces. The fine particles can irritate your lungs if inhaled. Even food-grade DE should be handled with care to minimize dust exposure.
Wrapping Up
Diatomaceous earth is a well-known insecticide, but its potential as an antifungal agent is less clear. We know that DE works against insects, and some people think it could work against fungus through similar methods. These methods include damaging fungal cell walls, drying out fungal spores, or changing the pH of the soil or surface where the fungus is growing.
Although the ways in which DE might work against fungus are clear, what’s less clear is how well it works. More research is needed to determine whether DE is effective against different kinds of fungus. In particular, we need in vitro studies (studies done in a lab) and in vivo studies (studies done in living organisms).
If more research shows that DE is effective against fungus, it could become a useful part of integrated pest management. However, until we know more about how well it works and whether it’s safe, we can’t say for sure whether DE is a good antifungal solution.