Diatomaceous earth

Diatomaceous earth is a fine, powdery silicate used in water filters, abrasives and absorbents. It is also used as a pesticide by some individuals. Diatomaceous earth is classified as a crystalline silicate.

What It Is

When ancient algae called diatoms died, their skeletal remains were left behind and can be found in large quantities below Earth’s surface. Mined today as diatomaceous earth, the tiny skeletons are an abrasive somewhat like pumice.


Since diatomaceous earth is so scratchy, it can be an irritant to the eyes, causing them to water and redden. Usually, flushing the eyes with water for at least 15 minutes will remove the irritation.


Some people also find that diatomaceous earth irritates the skin and causes red patches and itching. These symptoms, too, can be minimized by rinsing the affected area with water.


The lungs and mucous membranes are especially susceptible to harm by diatomaceous earth. Inhaling the powder can cause coughing or lead to difficulty breathing. Getting fresh air helps clear out the irritant.

Long-term Health

Long-term exposure to diatomaceous earth can lead to silicosis, a non-cancerous lung disease that causes scarring of the lung tissue. The International Agency for Research on Cancer (IARC) has classified crystalline silicates, including diatomaceous earth, as a carcinogen.