# The Bread and Flour (Wales) Regulations 2025, Schedule 2: Specification for E 170 calcium carbonate

Extent: E+W

Specification for E 170 calcium carbonate for the purpose of Schedule 1, paragraph 1, Table 1
(1) European Inventory of Existing Commercial Chemical Substances, as published in OJ No C 146A, 15.6.1990, p.1.
(2) Sum of ethylene oxide and 2-chloroethanol expressed as ethylene oxide (i.e. ethylene oxide + (0.55 × 2-chloroethanol)).
Synonyms
CI Pigment White 18; Chalk
Definition
Calcium carbonate is the product obtained from ground limestone or by the precipitation of calcium ions with carbonate ions.
Colour Index No
77220
EINECS number
Calcium carbonate: 207-439-9
Limestone: 215-279-6
Chemical name
Calcium carbonate
Chemical formula
CaCO3
Molecular weight
100.1 g/mol
Assay
Content ≥ 98% on the anhydrous basis
Description
White crystalline or amorphous, odourless and tasteless powder
Identification
Solubility
Practically insoluble in water and in alcohol. Dissolves with effervescence in diluted acetic acid, in diluted hydrochloric acid and in diluted nitric acid, and the resulting solutions, after boiling, give positive tests for calcium.
Purity
Loss on drying
≤ 2.0% (200°C, 4 hours)
Acid-insoluble substances
≤ 0.2%
Magnesium and alkali salt
≤ 1.0%
Fluoride
≤ 50 mg/kg
Antimony (Sb)
≤ 100mg/kg, singly or in combination
Copper (Cu)
Chromium (Cr)
Zinc (Zn)
Barium (Ba)
Arsenic (As)
≤ 3 mg/kg
Lead (Pb)
≤ 3 mg/kg
Cadmium (Cd)
≤ 3 mg/kg
Ethylene oxide
Total residues of ethylene oxide, irrespective of origin, must not exceed 0.1 mg/kg

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Source: https://www.legislation.gov.uk/wsi/2025/88/schedule/2 (the official version)
Page: https://openlegislation.uk/bread-and-flour-wales-regulations-2025/schedule-2
Contains public sector information licensed under the Open Government Licence v3.0. Source: legislation.gov.uk, The National Archives.