Calcium Silicate
The short version
A calcium silicate anti-caking agent — common in dry mixes and powdered seasonings.
It's widely considered safe at the amounts used in food, so we mark it green. The Safety section below has the details.
Safety profile
JECFA has allocated an ADI 'not specified'. In its 2018 re-evaluation, EFSA concluded that the safety of calcium silicate as a food additive cannot be assessed because reliable data on subchronic and chronic toxicity, carcinogenicity and reproductive toxicity were lacking, and considered the earlier EU group ADI 'not specified' obsolete. Absorption is very low, although silicon accumulation in liver and kidney was reported in rats at high doses. Provides small amounts of dietary calcium, but the additive level is nutritionally negligible.
Sources
- EFSA — Re-evaluation of calcium silicate (E 552), magnesium silicate (E 553a(i)), magnesium trisilicate (E 553a(ii)) and talc (E 553b) as food additives (2018) — EFSA (EFSA Journal 2018;16(8):5375, PMC copy), 2018. EFSA could not assess safety; SCF group ADI 'not specified' considered obsolete; low absorption
- WHO JECFA database — Calcium silicate (INS 552) — WHO / JECFA, 2015. JECFA ADI 'not specified'
- 21 CFR 172.410 — Calcium silicate — US eCFR (Office of the Federal Register), 2026. US anticaking use limits (2% of food, 5% of baking powder)
Checked against these sources on .
Educational information only. Not medical, dietary or veterinary advice. Spotted an error? Tell us.