Calcium Cyanamide

Calcium cyanamide is a calcium compound with the molecular formula CaCN2. It is formed when calcium carbide reacts with nitrogen. [fusion_builder_container hundred_percent=”yes” overflow=”visible”][fusion_builder_row][fusion_builder_column type=”1_1″ background_position=”left top” background_color=”” border_size=”” border_color=”” border_style=”solid” spacing=”yes” background_image=”” background_repeat=”no-repeat” padding=”” margin_top=”0px” margin_bottom=”0px” class=”” id=”” animation_type=”” animation_speed=”0.3″ animation_direction=”left” hide_on_mobile=”no” center_content=”no” min_height=”none”][1]

Calcium cyanamide occurs as glistening, hexagonal crystals. Pure calcium cyanamide is non-volatile and non-combustible. However, commercial grades may contain small amounts of calcium carbide, which will decompose in water to produce acetylene which is very flammable and used in welding. Commercial grades may occur as greyish-black lumps of powder. It is essentially insoluble in water, but undergoes partial hydrolysis to form soluble calcium hydrogen cyanamide. [2]




  • Calcium cyanamide is used in the manufacture of calcium cyanide, melamine, and dicyandiamide.
  • Calcium cyanamide can be used in the hardening of iron and steel.
  • It is used as a nitrogen source in fertiliser.
  • In veterinary medicine, calcium cyanamide is used for the elimination of parasitic worms.
  • Calcium cyanamide was registered for use as a pesticide, however, as of 3 December 1986, it is no longer registered for pesticidal use in California.


Sources & Routes of Exposure


Sources of Exposure [3]


Occupational exposure to calcium cyanamide may occur during its manufacture and use.


Routes of Exposure [2]


Probable routes of human exposure to calcium cyanamide are inhalation, ingestion, and dermal contact.


Health Effects [3]


Acute Effects


  • Calcium cyanamide is irritating to the eyes, skin, and respiratory tract in humans. Acute inhalation exposure may cause gastritis, rhinitis, pharyngitis, laryngitis, and tracheobronchitis.
  • Acute oral exposure of humans may cause a vasomotor reaction, resulting in intense localised erythematous flushing of the face, upper body, and arms, with headache, dizziness, fatigue, vertigo, congestion of the mucosa, nausea, and vomiting also reported.
  • Tachycardia and hypotension have also been observed in humans following acute oral exposure.
  • Peripheral neuropathy was reported in one case of acute oral exposure in a human.
  • Effects on liver enzymes have been reported in rats acutely exposed by ingestion.
  • Acute animal tests in rats, mice, and rabbits have demonstrated calcium cyanamide to have moderate to high acute toxicity from oral exposure and high acute toxicity from dermal exposure.


Chronic Effects


  • Chronic occupational exposure has been reported to cause chronic rhinitis with perforation of the nasal septum in workers.
  • Chronic dermal exposure may result in slow-healing dermal ulceration in humans.
  • EPA has not established a Reference Concentration (RfC) or a Reference Dose (RfD) for calcium cyanamide.


Reproductive/Developmental Effects


  • No information is available on the reproductive or developmental effects of calcium cyanamide in humans or animals.


Cancer Risk


  • No information is available on the carcinogenic effects of calcium cyanamide in humans.
  • EPA has not classified calcium cyanamide with respect to potential carcinogenicity.
  • A formulation of calcium cyanamide in the diet was not found to be carcinogenic in a two-year National Toxicology Program study in rats or mice.


Safety [4]

First Aid Measures


  • Eye Contact: Check for and remove any contact lenses. In case of contact, immediately flush eyes with plenty of water for at least 15 minutes. Get medical attention immediately.
  • Skin Contact: In case of contact, immediately flush skin with plenty of water. Cover the irritated skin with an emollient. Remove contaminated clothing and shoes. Wash clothing before reuse. Thoroughly clean shoes before reuse. Get medical attention.
  • Serious Skin Contact: Wash with a disinfectant soap and cover the contaminated skin with an anti-bacterial cream. Seek immediate medical attention.
  • Inhalation: If inhaled, remove to fresh air. If not breathing, give artificial respiration. If breathing is difficult, give oxygen. Get medical attention.
  • Serious Inhalation: Evacuate the victim to a safe area as soon as possible. Loosen tight clothing such as a collar, tie, belt or waistband. If breathing is difficult, administer oxygen. If the victim is not breathing, perform mouth-to-mouth resuscitation. Seek medical attention.
  • Ingestion: Do NOT induce vomiting unless directed to do so by a medical personnel. Never give anything by mouth to an unconscious person. If large quantities of this material are swallowed, call a physician immediately. Loosen tight clothing such as a collar, tie, belt or waistband.


Exposure Controls & Personal Protection


Engineering Controls


  • Use process enclosures, local exhaust ventilation, or other engineering controls to keep airborne levels below recommended exposure limits.
  • If user operations generate dust, fume or mist, use ventilation to keep exposure to airborne contaminants below the exposure limit.


Personal Protective Equipment


The following personal protective equipment is recommended when handling calcium cyanamide:


  • Splash goggles;
  • Lab coat;
  • Dust respirator (be sure to use an approved/certified respirator or equivalent);
  • Gloves.


Personal protective equipment in case of large spill:

  • splash goggles;
  • Full suit;
  • Dust respirator;
  • Boots;
  • Gloves;
  • A self contained breathing apparatus should be used to avoid inhalation of the product.
  • Suggested protective clothing might not be sufficient; consult a specialist BEFORE handling this product.


Regulation [4,5,6]


United States


OSHA: The United States Occupational Safety & Health Administration has set an airborne permissible exposure limit (PEL) for calcium cyanamide of 5mg/m3 (as Cyanide) averaged over an 8-hour workshift.


NIOSH: The National Institute for Occupational Safety & Health has set a recommended airborne exposure limit for calcium cyanamide of 0.5mg/m3 averaged over a 10-hour workshift.


ACGIH: The American Conference of Governmental Industrial Hygienists has set a recommended airborne exposure limit for calcium cyanamide of 0.5mg/m3 averaged over an 8-hour workshift.




Safe Work Australia: Safe Work Australia has set a time weighted average concentration for calcium cyanamide of 0.5mg/m3 averaged over an 8-hour workshift.