Is diatomaceous earth safe during pregnancy?

What does the evidence say about diatomaceous earth during pregnancy?

1. FDA has said it has not evaluated the safety of diatomaceous earth for direct addition to food and is not aware of an independent GRAS (generally recognized as safe) determination for that use, and the agency has taken enforcement action against a company that marketed it as an "internal de-wormer" and for other unapproved health claims. 1
2. The food-related uses FDA does recognize for diatomaceous earth are narrow industrial ones, like a filtration aid, rather than direct ingestion as a supplement. 1
3. Diatomaceous earth's best-documented health risk is inhaling the dust: heavy, repeated occupational exposure has been linked to silicosis, lung cancer, and other lung disease, which is relevant to anyone applying a food-grade powder for pest control at home. 2
4. A food-safety panel that reviewed diatomaceous earth as an animal feed ingredient found it safe for animals at the doses studied and identified inhalation, not oral intake, as the main hazard, but the review did not include any reproductive or developmental studies in any species. 3
5. Research on ingested, food-grade diatomaceous earth in a living body is still early and animal-only: the authors of one recent study described it as the first look at these particular effects in a female rat model, with no established human dose or safety data yet. 4

Is diatomaceous earth safe in each trimester?

• First trimester. There's no diatomaceous-earth-specific pregnancy research for any trimester, first included. If nausea already has you wary of new textures or powders, that's one more reason this isn't the trimester to start experimenting with an unproven supplement.
• Second trimester. The same lack of human safety data holds through the second trimester. If you already use food-grade diatomaceous earth for household pest control, applying it in a well-ventilated space and staying away from the powder while it's airborne limits the one health effect that is well documented: lung irritation from inhaling the dust.
• Third trimester. No new pregnancy-specific data emerges by the third trimester either. If you're using it around the house, the same inhalation-avoidance approach applies, and swallowing it as a supplement still isn't something regulators or researchers have evaluated for safety at any stage of pregnancy.