What is Calcium Chloride?
Calcium chloride is an inorganic salt that is highly soluble in water. It is known for its hygroscopic properties, meaning it readily attracts and absorbs water molecules from its surroundings. It is often sold as white flakes, pellets, or powder. Its versatility means it is used across a wide range of industries, including road construction for dust control, food preservation, and medical applications.
The Chemical Properties that Pose Risks
Two key chemical properties of calcium chloride explain its potential dangers:
- Exothermic Reaction with Water: When calcium chloride dissolves in water, it releases a significant amount of heat. This can cause thermal burns if it comes into contact with moist skin or eyes. This is a primary hazard to be aware of during mixing or in case of a spill where it encounters water.
- Hygroscopic Nature: Its ability to aggressively pull moisture from the air also means it can pull moisture from living tissues, causing dehydration and irritation. This effect contributes to the potential for skin and eye damage upon contact.
Health Hazards to Humans and Pets
Exposure to calcium chloride can occur through various routes, each with its own set of risks:
Skin and Eye Contact
Direct contact with calcium chloride can lead to irritation, redness, and a burning sensation. Prolonged or repeated exposure can cause dermatitis, cracking of the skin, or even chemical burns due to its moisture-absorbing and exothermic properties. If the chemical comes into contact with the eyes, it can cause serious irritation, pain, and potentially permanent corneal injury.
Inhalation Exposure
Inhaling calcium chloride dust or mist can cause irritation to the respiratory tract, including the nose, throat, and lungs. Symptoms may include coughing, sneezing, and shortness of breath. In poorly ventilated areas or during large-scale use, this is a significant concern for workers.
Ingestion Dangers
Accidental ingestion of calcium chloride poses serious health risks. It can cause burns to the mouth, throat, and gastrointestinal tract. Symptoms include severe stomach pain, nausea, and vomiting. In extreme cases, particularly with large quantities, it can lead to gastric necrosis and other severe systemic effects. It is critical to seek immediate medical attention if ingestion occurs.
Hazards for Pets
Just like humans, pets are susceptible to the hazards of calcium chloride, especially from de-icing products. Pets can ingest the chemical by licking their paws after walking on treated surfaces. Ingestion can lead to severe gastrointestinal upset, vomiting, diarrhea, and potentially more serious electrolyte imbalances. Contact with paw pads can also cause irritation and dryness.
Comparison of De-icing Agents
Calcium chloride is often compared to other ice melts. The following table illustrates some key differences:
| Feature | Calcium Chloride | Sodium Chloride (Rock Salt) | Calcium Magnesium Acetate (CMA) |
|---|---|---|---|
| Toxicity | Irritant; moderate to high risk, especially with ingestion or contact. | Moderate risk; large ingestion can cause high sodium levels. | Non-toxic to mammals; low risk. |
| Effect on Plants | Can increase soil salinity and harm plants. | Can damage plants and lawns. | Biodegradable; less harmful to plants. |
| Exothermic Reaction | Yes, produces heat when dissolving, increasing burn risk. | No, does not produce heat. | No. |
| Corrosiveness | Corrosive to metals and concrete, though less so than rock salt. | Very corrosive to metal and concrete. | Non-corrosive. |
Essential Safety and Handling Practices
To mitigate the hazards of calcium chloride, follow these safety measures:
- Personal Protective Equipment (PPE): Always wear appropriate gear when handling, including safety goggles and chemical-resistant gloves (e.g., rubber or neoprene). A synthetic apron can also provide added protection.
- Ventilation: Work in a well-ventilated area or outdoors to avoid inhaling dust.
- Mixing Precautions: When mixing with water, use cool water (below 80°F) and add the calcium chloride slowly to prevent a sudden, violent exothermic reaction that can cause spattering.
- Proper Storage: Store calcium chloride in a cool, dry place, sealed in its original, airtight container. This prevents it from absorbing moisture and clumping.
- Clean-up Procedures: For spills, sweep up the solid material and place it in a suitable container for disposal. Avoid flushing large spills into sewers or waterways, as it can harm the environment.
For more detailed information on handling specific chemicals, refer to official safety resources, such as the Occupational Safety and Health Administration (OSHA).
Emergency First Aid Procedures
- Skin Contact: Immediately flush the affected area with plenty of cool water for at least 15 minutes. Remove any contaminated clothing. Wash the area with soap and water, and seek medical attention if irritation persists.
- Eye Contact: Flush eyes with plenty of water for at least 15 minutes while holding eyelids open. Remove contact lenses if present and easy to do. Do not rub the eyes. Seek immediate medical attention.
- Inhalation: Move the affected person to fresh air. If breathing is difficult, give oxygen. Seek medical attention if symptoms persist.
- Ingestion: Rinse the mouth with water. Do NOT induce vomiting. Immediately seek medical attention. Never give anything by mouth to an unconscious person.
Environmental Impact
Beyond the direct health risks, improper use and disposal of calcium chloride can harm the environment. The increased salinity from runoff can damage local waterways and harm aquatic life. The salt can also affect soil quality, potentially inhibiting plant growth. Always follow local regulations for disposal and use caution to avoid over-application, especially near sensitive ecosystems. Responsible handling is key to minimizing both health and environmental risks.
