Diatomaceous Earth Fact Sheet (2024)

• What is diatomaceous earth?
• What are some products that contain diatomaceous earth?
• How does diatomaceous earth work?
• How might I be exposed to diatomaceous earth?
• What are some signs and symptoms from a brief exposure to diatomaceous earth?
• What happens to diatomaceous earth when it enters the body?
• Is diatomaceous earth likely to contribute to the development of cancer?
• Has anyone studied non-cancer effects from long-term exposure to diatomaceous earth?
• Are children more sensitive to diatomaceous earth than adults?
• What happens to diatomaceous earth in the environment?
• Can diatomaceous earth affect birds, fish, and other wildlife?

What is diatomaceous earth?

Diatomaceous earth is made from the fossilized remains of tiny, aquatic organisms called diatoms. Their skeletons are made of a natural substance called silica. Over a long period of time, diatoms accumulated in the sediment of rivers, streams, lakes, and oceans. Today, silica deposits are mined from these areas.

Silica is very common in nature and makes up 26% of the earth's crust by weight.Various forms of silica include sand, emerald, quartz, feldspar, mica, clay, asbestos,and glass. Silicon, a component of silica, does not exist naturally in its pureform. It usually reacts with oxygen and water to form silicon dioxide. Silicon dioxide has two naturally occurring forms: crystalline and amorphous. Most diatomaceous earth is madeof amorphous silicon dioxide. However, it can contain very low levels of crystallinesilicon dioxide. The first pesticide products containing silicon dioxide(diatomaceous earth) were registered in 1960 to kill insects and mites.

What are some products that contain diatomaceous earth?

Products containing diatomaceous earth are most commonly dusts. Other formulations include wettable powders and pressurized liquids. Currently, there are over 150 products registered for use inside and outside of buildings, farms, gardens, and pet kennels. Some products can also be used directly on dogs and cats. Diatomaceous earth products are registered for use against bed bugs, co*ckroaches, crickets, fleas, ticks, spiders, and many other pests.

There are thousands of non-pesticide products that contain diatomaceous earth. These include skin care products, toothpastes, foods, beverages, medicines, rubbers, paints, and water filters. The Food & Drug Administration lists diatomaceous earth as "Generally Recognized as Safe". "Food grade" diatomaceous earth products are purified. Theymay be used as anticaking materials in feed, or as clarifiers for wine and beer.

Always follow label instructions and take steps to minimize exposure. If any exposures occur, be sure to follow the First Aid instructions on the product label carefully. For additional treatment advice, contact the Poison Control Center at800-222-1222. If you wish to discuss a pesticide problem, please call 800-858-7378.

How does diatomaceous earth work?

Diatomaceous earth is not poisonous; it does not have to be eaten in order to be effective. Diatomaceous earthcauses insects to dry out and die by absorbing the oils and fats from the cuticle of the insect's exoskeleton. Its sharpedges are abrasive, speeding up the process. It remains effective as long as it is kept dry and undisturbed.

How might I be exposed to diatomaceous earth?

People can be exposed to diatomaceous earth if they breathe in the dust, eatit, get it on their skin, or get it in their eyes. For example, when applying thedust or when entering a treated area before the dust has settled. Exposurescan also occur if products are accessible to children or pets. Exposure can belimited by reading and following label directions.

What are some signs and symptoms from a brief exposure to diatomaceous earth?

If breathed in, diatomaceous earth can irritate the nose and nasal passages. If an extremely large amount is inhaled,people may cough and have shortness of breath. On skin, it can cause irritation and dryness. Diatomaceous earth mayalso irritate the eyes, due to its abrasive nature. Any dust, including silica, can be irritating to the eyes.

What happens to diatomaceous earth when it enters the body?

When diatomaceous earth is eaten, very little is absorbed into the body. The remaining portion is rapidly excreted.Small amounts of silica are normally present in all body tissues, and it is normal to find silicon dioxide in urine. In onestudy, people ate a few grams of diatomaceous earth. The amount of silicon dioxide in their urine was unchanged.

After inhalation of amorphous diatomaceous earth, it is rapidly eliminated from lung tissue. However, crystalline diatomaceousearth is much smaller, and it may accumulate in lung tissue and lymph nodes. Very low levels of crystallinediatomaceous earth may be found in pesticide products.

Is diatomaceous earth likely to contribute to the development of cancer?

When mice were forced to breathe diatomaceous earth for one hour each day for a year, there was an increase in lungcancers. When rats were fed silica at a high dose for two years, there was no increase in cancer development.

Most diatomaceous earth is made of amorphous silicon dioxide. However, it can contain very low levels of crystallinesilicon dioxide. Amorphous diatomaceous earth has not been associated with any cancers in people.

Has anyone studied non-cancer effects from long-term exposure to diatomaceous earth?

In a rabbit study, researchers found no health effects after applying diatomaceous earth to the rabbits' skin five timesper week for three weeks. In a rat study, researchers fed rats high doses of diatomaceous earth for six months. Theyfound no reproductive or developmental effects. In another rat study, the only effect was more rapid weight gain. Thatstudy involved 90 days of feeding rats with a diet made of 5% diatomaceous earth.

When guinea pigs were forced to breathe air containing diatomaceous earth for 2 years, there was slightly more connectivetissue in their lungs. When researchers checked before the 2-year mark, no effects were found.

A very small amount of crystalline diatomaceous earth may be found in pesticide products. Long-term inhalation ofthe crystalline form is associated with silicosis, chronic bronchitis, and other respiratory problems. The bulk of diatomaceousearth is amorphous, not crystalline. The amorphous form is only associated with mild, reversible lung inflammation.

Are children more sensitive to diatomaceous earth than adults?

Children may be especially sensitive to pesticides compared to adults. However, there are currently no data to concludethat children have an increased sensitivity specifically to diatomaceous earth.

What happens to diatomaceous earth in the environment?

Silicon is a major component of diatomaceous earth. It is the second mostabundant element in soils. It's a common component of rocks, sands, andclays. It is also abundant in plants and plays a role in their growth anddevelopment. Due to its chemical makeup, diatomaceous earth is not degradedby microbes or by sunlight. Also, it does not emit vapors or dissolvewell in water.

The ocean contains vast amounts of diatomaceous earth. Many marineorganisms use it to build their skeletons.

Can diatomaceous earth affect birds, fish, or other wildlife?

Diatomaceous earth is practically non-toxic to fish and aquatic invertebrates. It is commonly encountered by birdsand other wildlife, and it's not known to be harmful. However, no toxicity evaluations for wildlife were found. Agencieshave stated that diatomaceous earth is unlikely to affect birds, fish, or other wildlife in a harmful way.

Diatomaceous earth is made of silicon dioxide. When chickens were fed a diet that contained less silicon dioxide than normal, their bone formation was harmed. This suggests that silicon dioxide plays an important role in bone formation.