Cobalt Chloride has been classified by IARC (International Agency for Research on Cancer) in Group 2B. Which states Cobalt Chloride is possibly carcinogenic to humans. Very toxic to aquatic organisms. May cause long term adverse effects in the environment.

Common Uses:

  • Blue Indicating Silica Gel:

Blue Cobalt ChloridePink Cobalt Chloride

The most common use for Cobalt Chloride is in a type of Desiccant named Blue Indicating Silica Gel. This product is in bead form and will turn from Blue to Pink when full absorbed. This is one of the most widely used indicating desiccant products and poses health risks and environmental issues.

Alternative Solution: Blue Indicating Silica Gel is being replaced with an alternative product that is reformulated and does not contain Cobalt Chloride, this is Orange Indicating Silica Gel. It has the same moisture absorption capacity and the indicating beads turn from Orange to Dark Green when fully absorbed.

  • Humidity Indicator Cards:

Humidity Indicator Cards are slips of paper that change color when a certain level of humidity is achieved. One common card is the 3 dot 30%/40%/50% card, but come in many sizes. A common type has blue dots and change to pink dots when the humidity level is achieved. These cards are injected with Cobalt Chloride.

Alternative Solution: There is a new line of Cobalt Free Humidity Indicator Cards on the market that are replacing the original Cobalt injected Humidity Indicator cards. These cards have the exact same function, just the dots start out yellow.

Others uses:

  • Science experiments

  • Color changing novelties

  • Binding agent in harden metals

  • Starting point for the synthesis of cobalt compounds in labs


Hazardous Effects of Cobalt Chloride:

 Very hazardous in case of skin contact (irritant), of eye contact (irritant), of ingestion, . Hazardous in case of skin contact (corrosive, sensitizer, permeator), of eye contact (corrosive), of inhalation (lung sensitizer). Non-corrosive for lungs. Liquid or spray mist may produce tissue damage particularly on mucous membranes of eyes, mouth and respiratory tract. Skin contact may produce burns. Inhalation of the spray mist may produce severe irritation of respiratory tract, characterized by coughing, choking, or shortness of breath. Severe over-exposure can result in death. Inflammation of the eye is characterized by redness, watering, and itching. Skin inflammation is characterized by itching, scaling, reddening, or, occasionally, blistering.