Other names for the additive (synonyms)
General information
Food additive additive E170 (calcium carbonates) is a general name for salts of carbonic acid in which calcium is bound to the carbonate group. Additive E170 belongs to the group of colorants, but it can also be used as an acidity regulator, leavening agent, and anti-caking agent. In everyday life, calcium carbonate is well known as ordinary white chalk.
In nature, calcium carbonates occur in the form of the minerals calcite, aragonite, and vaterite. These forms are widely distributed in the Earth's crust and form the basis of many sedimentary rocks, including limestone, marble, and chalk. Living organisms also actively use this compound: shells of mollusks, corals, and sponge skeletons consist mainly of calcium carbonate.
For the food industry, additive E170 is obtained by mining and purifying chalk deposits, as well as from marble, which provides the highest degree of purity. As a result of technological processing, a fine white powder is produced.
Calcium carbonate is an inorganic salt of carbonic acid, practically insoluble in water and ethanol. The physical properties of additive E170 include white color, absence of odor, and crystalline structure. When heated above 800°C, calcium carbonate decomposes into calcium oxide and carbon dioxide.
According to the International Food Additives Classification and Numbering System Codex Alimentarius: CXG 36-1989, food additive E170 is divided into two subtypes:
- E170(i) – calcium carbonate, with the chemical formula CaCO₃;
- E170(ii) – calcium bicarbonate, with the chemical formula Ca(HCO₃)₂.
However, the General Standard for Food Additives (STAN 192-1995) includes only the first subtype — E170(i) — calcium carbonate. In European legislation, according to Regulation (EC) No. 1333/2008, the designation additive E170 refers exclusively to calcium carbonate.
Effects on the Body
Benefits of Additive E170
Calcium carbonates play an important role in the human body, being the main source of calcium — a microelement necessary for the formation of bones and teeth. They participate in blood clotting processes, maintain constant osmotic pressure, and regulate enzyme activity and intracellular processes.
In medicine and pharmacy, calcium carbonate is widely used as a component of medicinal products and dietary supplements designed to compensate for calcium deficiency. It is also used as an antacid to reduce stomach acid.
Studies on rats showed that calcium carbonate more effectively binds hemin and reduces markers of carcinogenesis compared to calcium phosphate.
Risks of Additive E170
Excessive intake of calcium carbonates can lead to hypercalcemia. Symptoms include nausea, abdominal pain, vomiting, muscle weakness, and disturbances in psycho-emotional state.
With significant overconsumption, calcium carbonates can cause the so-called “milk-alkali syndrome,” accompanied by severe kidney and heart dysfunction, potentially leading to death.
However, this does not apply to consumption of additive E170 in food products, as the doses used in the food industry are much lower. Nevertheless, experts recommend taking into account all sources of calcium in the diet, including supplements, fortified foods, and medicinal products.
The JECFA committee in 1965 established the ADI status for calcium carbonate as “not limited.” A similar conclusion was made by the SCF (Scientific Committee on Food, EU) in 1990, grouping carbonates together.
In 2003, the maximum safe intake level of calcium from all sources (UL) was set at 2500 mg/day. The recommended daily preventive dose of calcium carbonate is 1.2–1.5 g per day.
In 2011, the EFSA Panel on Food Additives re-evaluated food additive E170 and noted that the toxicological database for calcium carbonate is limited; however, available data do not raise concerns. The additive is classified as safe, as adverse effects appear only with excessive calcium intake from all sources.
In 2023, the FAF Panel on Food Additives and Flavourings assessed the safety of additive E170 for infants. The panel concluded that there is no need to establish a numerical ADI for calcium carbonate and that, in principle, there are no concerns regarding the safety of calcium carbonate exposure at current authorized uses and levels for all age groups, including infants younger than 16 weeks.
The US Food and Drug Administration (FDA) also classifies calcium carbonate as generally recognized as safe (GRAS).
Uses
In the food industry, additive E170 performs several functions:
- colorant — gives products a white hue;
- acidity regulator — stabilizes pH;
- leavening and anti-caking agent — prevents clumping and improves mixture texture.
Additive E170 is used in the production of bakery products, confectionery, dry mixes, chewing gum, powdered milk, cream substitutes, powdered sugar, and various beverages.
Calcium carbonates have extremely wide applications not only in the food industry but also in various sectors of the economy and industry. Due to their physicochemical properties (white color, neutrality, low toxicity, low cost, ability to bind acids), they have become a universal material.
Main areas of calcium carbonate application:
- Medicine and pharmacy – used in medicinal products to correct calcium deficiency, as an antacid for heartburn and gastritis, and in dietary supplements.
- Cosmetics and hygiene – included in toothpastes, powders, decorative cosmetics, and personal care products.
- Household chemicals – used in cleaning powders, shoe care products, and polishes.
- Paper industry – serve as filler and whitening agent in paper and cardboard production.
- Glass industry – an important component in the manufacture of glass and fiberglass.
- Polymer industry – used as filler in plastics, linoleum, tiles, sanitary ware, and carpets.
- Paints and coatings – a component of pigments and primers.
- Construction – used in cement, putties, sealants, and dry construction mixes.
- Agriculture – used as lime material to neutralize soil acidity and improve its structure.
- Ecology – employed in treatment systems, e.g., to bind sulfur compounds in flue gas cleaning.
Legal Status
In the European Union, additive E170 is included in the list of authorized substances according to Regulation (EC) No. 1333/2008. In Ukraine, it is also permitted for use in the food industry and included in national regulations. In the USA, calcium carbonate has GRAS status. Its use is also authorized in Canada, Japan, Australia, and most other countries.
No strict ADI has been established for additive E170, as its toxicity manifests only with a significant excess of normal calcium intake.