Calcium hydroxide is also known as calcium hydrate and slaked lime. Its C.A.S. number, which identifies it as a chemical by the Chemical Abstracts Service, is 1305-62-0. Its chemical formula is Ca(OH)2, where Ca is the element calcium, O is oxygen, and H is hydrogen. (OH)2 is the chemical name for hydroxide. It's molecular weight is 74.09. It is not flammable and is coded green for general storage.
Calcium hydroxide has many industrial uses. It is used as a filler for making solid oil, in the manufacturing of brake pads, pesticides, and ebonite, a hard rubber material. It can be used in dry paint mix, sewage treatment, as a fungicide, and in solvents. It is also used in the tanning industry as an acid neutralizer and the ornamental fish industry as a calcium supplement for snails, algae, and coral. Dentists also use it in root canals because of its bone-strengthening and anti-microbial properties. Personal protective equipment needed in laboratory use includes goggles, shield, apron and lab coat, vent hood, and gloves.
Calcium hydroxide is used as an ingredient in many home and garden products. It is alkaline, which means that it is the opposite of an acid chemically. It can be substituted for lye in hair-relaxing agents and is used as a depilatory in hair-removal products. It is also used in the food industry to clear brine, process beverages, and to add nutritional value to foods such as corn.
Despite its usage in the food industry, calcium hydroxide can be very caustic and kill in less than 24 hours. Symptoms of exposure include respiratory problems, internal bleeding, severe burns, blistering, and blindness. If ingested, vomiting must not be induced. Instead, have the patient drink large amounts of water if he or she is conscious. Flush skin and eyes with water for 15 minutes if contact occurs. The patient must get to fresh air and may need oxygen or artificial respiration. Call 911.
Localized ventilation and a NIOSH respirator are necessary to keep under the exposure limitations of 15 mg/m3 (total dust) and 5 mg/m3 (respirable fraction).