CHEMICAL SUBSTANCE DATASHEET
|
CHEMICAL SUBSTANCE IDENTIFICATION |
|
|
Chemical name |
Calcium carbonate[1] |
|
Synonyms |
Aragonite, Chalk, calcite, etc [1] |
|
IUPAC name |
calcium carbonate [1] |
|
CAS No |
471-34-1 |
|
REACH registration number |
fully registered [1] |
|
EC No |
207-439-9 [1] |
|
Molecular formula |
CH2O3.Ca [1] |
|
Substance group/chemical family |
mono-constituent substance/inorganic [1] it is the major component of limestone |
|
Appearance Physical state Odour Form Colour |
solid @ 20°C and 1013 hPa [1] fine powder which tends to form clumps, at 20 ± 0.5 °C [1] hexagonal crystals or powder. [2] white [1] |
|
USES AND HANDLING ISSUES |
|
|
Relevant identified uses |
Calcium carbonate is a direct food additive used as a dough strengthener to modify starch and gluten, producing a more stable dough, nutrient supplement which is necessary for the body's nutritional and metabolic processes, pH control agent to change or maintain active acidity or basicity. Production of adhesives, matches, pencils; crayons, linoleum, insulating compounds, welding rods. In foods, cosmetics, antibiotics; in pharmaceuticals as tablet and capsule diluent; removing acidity of wines. In analytical chemistry for detecting and determining halogens in organic combinations. It is used as source of lime; neutralizing agent; whitewash; Portland cement; carbon dioxide generation (laboratory). Acts as a base in its application as a soil conditioner, neutralizer of surface waters, industrial acid neutralizer, and in a limestone slurry as a stack gas scrubber to remove SO2. Used in industrial finishes and powder coatings. Limestone is also used as a metallurgical flux. Buffering agent, abrasive, bulking agent, opacifying agent, oral care agent; in dusting powders or body powders. [2] |
|
Handling considerations |
HANDLING: Store separated from acids, aluminium and ammonium salts. [2] |
|
PHYSICO-CHEMICAL PROPERTIES |
|
|
Molecular weight |
100.09 g/mol [2] |
|
Bulk density/Specific gravity |
The relative density of bulk calcium carbonate is between 2.7 and 2.95 depending on its crystalline form. [1]
|
|
pH |
8-9 [2] |
|
Particle size |
|
|
EC |
|
|
Melting/Freezing point |
|
|
Boiling point |
Bulk calcium carbonate decomposes before melting hence boiling point is not required. [1] |
|
Flash point |
Not required for inorganic substances. [1] |
|
Flammability |
not classified [1] Noncombustible Solid [2] Based on a study performed using uncoated nano calcium carbonate in which it failed to ignite in the preliminary screening test, bulk calcium carbonate is not classified as a readily combustible solid under Division 4.1. [1] |
|
Vapour density |
|
|
Vapour pressure |
Bulk calcium carbonate is a solid that melts above 300 °C hence vapour pressure is not required. [1] |
|
Solubility in water |
16.6 mg/L @ 20 °C [1] The water solubility of bulk calcium carbonate was determined to be 16.6 mg/L at 20 °C in a GLP study performed in accordance with OECD TG 105 (Walker & White, 2010). This result is supported by data from a peer reviewed handbook showing the solubility to be in the range of 6.6 -11 mg/L at 20 °C. [1] Practically insoluble in water. [2] |
|
Solubility in organic solvents |
Practically insoluble in alcohol. [2] |
|
Solubility in inorganic solvents |
soluble in dilute acid [2] |
|
Hydrolysis |
|
|
Ionicity in water |
|
|
Surface tension |
Bulk calcium carbonate is not expected to be surface active, based on structure. [1] |
|
Dispersion properties |
|
|
Explosiveness |
non explosive [1] The explosive properties of calcium carbonate have been predicted negative based on the chemical structure and experience of handling and use. [1] |
|
Other properties |
Uncoated nano calcium carbonate has been determined not to be auto flammable. This result is read across to bulk calcium carbonate. [1] The oxidising properties of bulk calcium carbonate have been predicted negative based on chemical structure and experience of handling and use. Classification is not required. [1] The dustiness of calcium carbonate (bulk) has been determined as follows: |
|
Stability and reactivity |
|
|
Chemical stability |
No decomposition if stored and applied as directed. [1] |
|
Reactivity hazards |
May react violently in contact with acids. [1] No rapid reaction with air No rapid reaction with water. [2] |
|
Corrosivity |
Non-corrosive [2] |
|
Polimerization |
|
|
Incompatibility with various substances |
May react violently in contact with acids. [1] Ignites and burns fiercely in contact with fluorine. Incompatible with acids, alum, ammonium salts, mercury & hydrogen, fluorine, magnesium [2] |
|
Special remarks on reactivity |
Avoid strong heating (decomposition). [1] |
|
Physical, chemical and biological coefficient |
|
|
Koc |
|
|
Kow |
Bulk calcium carbonate is inorganic hence log Kow is not relevant. [1] |
|
pKa |
|
|
log Kp |
|
|
Henry-constant |
|
|
ENVIRONMENTAL FATE AND BEHAVIOUR |
|
|
Artificial pollution sources |
|
|
General terrestrial fate |
The accumulation and mobility of calcium carbonate in soils has been documented in soil chemistry as the process of “calcification”. Calcification is the general process by which naturally occurring calcium carbonate or the product of dissolved calcium ions and either bicarbonate or carbonate ions (from dissolved carbon dioxide, the dominant form of the dissolved product being dependant on the solution pH) accumulates in soils. Most commonly, calcium carbonate accumulates in subsurface horizons of soils in subhumid, semiarid, or arid regions. Calcium carbonate has a propensity to leach through soil if water is applied, i.e. it does have some mobility through soil, providing sufficient water is present. As it moves downwards into layers where the water content is low, the leaching will stop. On this basis, calcium carbonate does not have a high potential for adsorption to soil. Calcium carbonate will be degraded in the environment by means other than biodegradation. The ions will dissociate; calcium will be assimilated by species in the water and is necessary to maintain a good chemical balance in soils, water and plants and carbonate will become part of the carbon cycle. [2] |
|
General aquatic fate |
Calcium carbonate presents only limited solubility in water and solubility characteristics are known to be sensitive to both solution pH and also the presence/partial pressure of carbon dioxide (which dissolves to give carbonate or bicarbonate ions). Calcium carbonate will be degraded in the environment by means other than biodegradation. The ions will dissociate; calcium will be assimilated by species in the water and is necessary to maintain a good chemical balance in soils, water and plants and carbonate will become part of the carbon cycle. [2] |
|
General atmospheric fate |
|
|
General persistence and degradability |
|
|
Abiotic degradation and metabolites |
In the environment, calcium carbonate will dissociate into calcium and carbonate ions. [1] |
|
Biodegradation and metabolites |
Bulk calcium carbonate is an inorganic substance and does not undergo hydrolysis or biodegradation. [1] |
|
Bioconcentration |
Calcium and carbonate ions are essential to all living organisms (flora and fauna) and their intracellular and extra-cellular concentrations are actively regulated. Therefore, bioaccumulation is not expected. [1] |
|
Volatilization |
|
|
Photolysis |
|
|
Hydrolysis |
Bulk calcium carbonate is an inorganic substance and does not undergo hydrolysis or biodegradation. [1] |
|
Soil adsorption and mobility |
The accumulation and mobility of calcium carbonate in soils has been documented in soil chemistry as the process of “calcification”. Calcification is the general process by which naturally occurring calcium carbonate or the product of dissolved calcium ions and either bicarbonate or carbonate ions (from dissolved carbon dioxide, the dominant form of the dissolved product being dependant on the solution pH) accumulates in soils. Most commonly, calcium carbonate accumulates in subsurface horizons of soils in subhumid, semiarid, or arid regions. [1] Calcium carbonate has a propensity to leach through soil if water is applied, i.e. it does have some mobility through soil, providing sufficient water is present. As it moves downwards into layers where the water content is low, the leaching will stop. On this basis, calcium carbonate does not have a high potential for adsorption to soil. [1] |
|
ENVIRONMENTAL CONCENTRATIONS |
|
|
Measured data |
Calcium carbonate range concentrations were reported as 4.9-85.2, 67.5-90.7, and 67.2-94.3 mg/kg in the sediments of Geothermal Springs, Mangrove Lagoon and the Santispac Bight, Baha Concepcion, Baja California Peninsula, respectively. [2]
|
|
ECOTOXICOLOGICAL INFORMATION |
|
|
General adverse effects on ecosystem |
|
|
Acute toxicity (LC50, EC50) |
|
|
Aquatic systems |
EC50 (fish, 96 h, mortality): >100% v/v No data are available for bulk calcium carbonate. A study is available for uncoated nano calcium carbonate. This study, performed to OECD TG 203, assessed the acute toxicity of uncoated nano calcium carbonate to Oncorhynchus mykiss (rainbow trout) in a limit test (Priestly, 2010). No mortalities or adverse effects were noted at the concentration tested. Hence, the 96 h LC50 for uncoated nano calcium carbonate was found to be >100% v/v saturated solution. The result from this study demonstrates that uncoated nano calcium carbonate is not acutely toxic to fish at the limit of its solubility in water. This result is read across to bulk calcium carbonate. [1]
EC50 (Daphnia magna, 48h, mobility): >100% v/v saturated solution [1] The acute toxicity of uncoated nano calcium carbonate to Daphnia magna has been investigated in a GLP study performed in accordance with OECD TG 202. The 48 h EC50 was >100% v/v saturated solution and the NOEC was 100% v/v saturated solution. The results from this study demonstrate that uncoated nano calcium carbonate is not acutely toxic to aquatic invertebrates at the limit of its solubility in water. This result is read across to bulk calcium carbonate. [1] EC50 (Desmodesmus subspicatus (green algae), growth rate and yield, 72 h): > 14 mg/L [1] The acute toxicity of uncoated nano calcium carbonate to algae has been investigated in a GLP study performed in accordance with OECD TG 201. The result from this study demonstrates that calcium carbonate is not acutely toxic to algae at the limit of its solubility in water. This result is read across to bulk calcium carbonate. [1] EC50 (microorganisms, activated sludge respiration inhibition testing, 3h): >1000 mg/L [1] The toxicity of uncoated nano calcium carbonate to aquatic microorganisms has been investigated in a GLP study performed in accordance with OECD TG 209. The effect of uncoated nano calcium carbonate on the respiration of activated sewage sludge micro-organisms gave a 3 h EC50 of greater than 1000 mg/L. The results of this study are read across to bulk calcium carbonate. [1] |
|
Terrestrial systems |
EC50 (soil microorganisms, nitrate formation rate, 28 days): > 1 000 mg/kg soil dw [1] The effect of uncoated nano calcium carbonate on the nitrogen transformation activity of soil microorganisms has been investigated in a GLP study performed in accordance with OECD Guideline 216. The 28 day EC50 was >1000 mg/kg soil dw and the NOEC was 1000 mg/kg soil dw. The result from this study demonstrates that calcium carbonate is not toxic to soil microorganisms. [1] |
|
Chronic toxicity (NOEC, LOEC) |
|
|
Aquatic systems |
NOEC (fish, mortality): 100% v/v saturated solution [1] NOEC (Daphnia magna, mobility): 100% v/v saturated solution [1] In an acute toxicity study to Daphnia magna with a saturated solution (100% v/v) of uncoated nano calcium carbonate no immobilisation or toxic effects were observed in any of the Daphnia magna exposed (Priestly, 2010). As a result, calcium carbonate is considered not acutely toxic to aquatic invertebrates and hence long term testing is considered to be unnecessary. [1]
NOEC (Desmodesmus subspicatus (green algae), growth rate and yield, 72 h): > 14 mg/L [1]
NOEC (microorganisms, activated sludge respiration inhibition testing, 3h): 1000 mg/L [1] The toxicity of uncoated nano calcium carbonate to aquatic microorganisms has been investigated in a GLP study performed in accordance with OECD TG 209. The NOEC after 3 hours exposure was 1000 mg/L. The results of this study are read across to bulk calcium carbonate. [1]
|
|
Terrestrial systems |
NOEC (soil microorganisms, nitrate formation rate, 28 days): 1 000 mg/kg soil dw [1] |
|
HUMAN HEALTH EFFECTS and PROTECTION |
|
|
Routes of human exposures |
inhalation, skin and/or eye contact [2] |
|
General effects |
Irritation eyes, skin, respiratory system; cough Target Organs: Eyes, skin, respiratory system [2] |
|
Endocrine disruption |
|
|
Mutagenicity |
The results of an in vitro gene mutation study in bacteria, an in vitro chromosome aberration study in mammalian cells and an in vitro gene mutation study in mammalian cells, performed using uncoated nano calcium carbonate and read across to bulk calcium carbonate, were all negative. It is concluded that bulk calcium carbonate is not genotoxic and does not warrant classification for mutagenicity under CLP. [1] |
|
Carcinogenicity |
No carcinogenicity classification is warranted for uncoated nano calcium carbonate according to CLP based on evidence from genotoxicity, repeat dose studies and long term human studies. [1] |
|
Reprotoxicity |
No treatment-related effects were observed for reproduction, a NOEL for reproductive toxicity was considered to be 1000 mg/kg bw/day. The results of this study are read across to bulk calcium carbonate. [1] |
|
Teratogenicity |
Bulk calcium carbonate showed no signs of developmental toxicity in a prenatal developmental screening toxicity test. [1] |
|
Skin, eye and respiratory irritations |
In the in vivo skin and eye irritation studies bulk calcium carbonate was non-irritant and therefore requires no classification under CLP. [1] Based on the results of an OECD TG 429 study performed using nano calcium carbonate and read across to bulk calcium carbonate, where the Stimulation Index was < 3, bulk calcium carbonate is considered to be a non-sensitiser and does not require classification. [1] |
|
Metabolism: absorption, distribution & excretion |
Maximal absorption occurs at doses of 500 mg or less taken with food. Oral bioavailability depends on intestinal pH, the presence of food and dosage. After ingestion /of CaCO3 tablets/, it is converted to sol calcium salts in stomach, and calcium is thereby made available for absorption. [2] Calcium is rapidly distributed taken up by skeletal tissues following absorption and distribution into extracellular fluids. Bone contains 99% of the body's calcium and the remaining 1% is approximately equally distributed between intracellular and extracellular fluids. [2] |
|
Exposure limits |
EXPOSURE LIMIT VALUES [1] Permissible Exposure Limit: 8-Hr Time Weighted Avg: 15 mg/ m3, total dust. [2] Permissible Exposure Limit: 8-Hr Time Weighted Avg: 5 mg/ m3, respirable fraction. [2] Recommended Exposure Limit: 10 Hour Time-Weighted Average: 10 mg/ m3 (total); 5 mg/cu m (respirable fraction). [2] |
|
Drinking water MAC |
|
|
Other information |
In general, calcium levels in the body are regulated by homeostatic processes. These homeostatic processes are able to deal with moderate increases in calcium intake: either by storage in bone or by excretion via urine, faeces or sweat. Therefore, calcium and calcium carbonate are not toxic to humans but are essential elements to life and serious disorders, such as retarded skeletal growth may result from calcium deficiency. [1] |
|
Animal toxicity data |
|
|
Acute toxicity (LD50) |
LD50 (rats, oral) > 2000 mg/kg bw in an OECD Guideline 420 study. Therefore bulk calcium carbonate does not require classification according to the criteria described in Regulation (EC) No 1272/2008. [1] LD50 (rats, inhalation) > 3 mg/L air in an OECD Guideline 403 study. The result was achieved at the maximum attainable concentration and is considered to be equivalent to a limit test conducted at 5 mg/L. Therefore, bulk calcium carbonate is not considered to be classified according to the criteria described in Regulation (EC) No 1272/2008. [1] LD50 (rats, dermal) > 2000 mg/kg bw in an OECD Guideline 402 study performed using uncoated nano calcium carbonate. This result is read across to the bulk form, therefore bulk calcium carbonate does not require classification according to the criteria described in Regulation (EC) No 1272/2008. [1] |
|
Chronic toxicity (NOEL, LOEL) |
NOEL (rats, oral, 90 days. repeated dose toxicity, systemic effects): 1000 mg/kg bw/day -no adverse effect observed [1] NOAEC (rats, inhalation, 90 days, systemic effects, repeated dose toxicity) : 399 mg/m³ no adverse effect observed [1] NOAEC (rabbit, inhalation, 90 days, local effects, repeated dose toxicity) : 212 mg/m³ no adverse effect observed [1] NOEL (rats, oral, reproductive toxicity): 1000 mg/kg bw/day [1] No treatment-related effects were observed for reproduction, a NOEL for reproductive toxicity was considered to be 1000 mg/kg bw/day. The results of this study are read across to bulk calcium carbonate. [1] |
|
ENVIRONMENTAL STANDARDS AND REGULATIONS |
|
|
REACH/CLP |
Not classified (data conclusive but not sufficient for classification) [1] No signal word [1] Bulk calcium carbonate is not classified as dangerous or harmful to the environment. [1] |
|
EINECS regulation |
̵ |
|
OSHA regulations etc. |
|
|
Disposal considerations |
WASTE FROM RESIDUES / UNUSED PRODUCTS |
|
OTHER INFORMATION, SPECIAL REMARKS |
|
|
Classification and proposed labelling with regard to toxicological data |
|
|
|
|
|
CREATED, LAST UPDATE |
|
|
Created |
2020.06.02. |
|
Last update |
2020.06.03. |
|
REFERENCES |
|
|
[1] ECHA, Calcium carbonate, https://echa.europa.eu/hu/registration-dossier/-/registered-dossier/16050, Accessed 2020. 06. 02 [2] PUBCHEM, Calcium carbonate, https://pubchem.ncbi.nlm.nih.gov/compound/Calcium-carbonate, Accessed 2020. 06. 03 |
|