Diatomaceous earth (DE) is a naturally occurring, soft, siliceous sedimentary rock that is composed mainly of the fossilized remains of diatoms, a type of microscopic hard-shelled algae. It typically contains about 80-90% silica, along with alumina and iron oxide, and is available as a fine powder that feels abrasive, similar to pumice powder. It has a variety of industrial, agricultural, and health-related uses.
Composition and Formation
Diatomaceous earth forms over millions of years from the accumulation of the silica-based skeletons of dead diatoms in lakes, streams, oceans, and wetlands. This fossilized silica accumulates in sedimentary deposits, often alongside volcanic materials, and results in a powdery, highly porous substance.
Uses
- Industrial: Used as a filtration aid, abrasive (in toothpaste and metal polishes), mechanical insecticide, absorbent for liquids, filler in plastics and rubber, insulation material, and in chromatography.
- Agricultural: Employed as an insecticide to control pests like fleas, bedbugs, cockroaches, and ticks by physically dehydrating them due to its abrasive nature.
- Household: Used as a deodorizer, facial exfoliator, and cat litter.
- Health Supplements: Food-grade diatomaceous earth, which is safe for human and animal consumption, is marketed as a source of silica for skin, nail, bone, and digestive health benefits, although scientific evidence is limited.
Grades
There are mainly two grades:
- Food-grade diatomaceous earth: Low in crystalline silica, safe for human and pet use, used for insecticide, health supplements, and as an anti-caking agent.
- Filter-grade diatomaceous earth: High in crystalline silica and not safe for consumption, typically used in pool filters and industrial processes.
Diatomaceous earth is versatile and valued both for its physical properties (abrasive, porous) and its natural origin from fossilized diatoms.
If more detailed uses, safety guidelines, or health impact information is needed, a follow-up can be done.