Super glue, known chemically as cyanoacrylate adhesive, is a fixture in households and workshops for its incredible bonding speed and strength. The common question of whether it is “toxic” often confuses chemical poisoning with physical harm, which are two very different hazards. While super glue is generally not considered a systemic poison, its rapid-acting chemistry creates significant risks for injury and irritation. Understanding the substance’s properties is the first step toward safe use, differentiating between a true chemical threat and an immediate physical danger.
Chemical Identity and Systemic Toxicity
Super glue is primarily composed of cyanoacrylate monomers, typically ethyl or methyl cyanoacrylate. The glue’s ability to bond instantly relies on a chemical process called anionic polymerization, initiated by trace amounts of moisture, such as the humidity in the air or on skin. When the liquid adhesive contacts water, the monomers rapidly link together to form long, inert plastic chains called polymers, releasing heat in an exothermic reaction.
Because this curing process is so fast, the liquid monomer quickly solidifies into a solid plastic mass, preventing it from being absorbed into the bloodstream. This rapid polymerization is the main reason why super glue is not classified as a systemic poison if accidentally ingested. The main internal risk is mechanical obstruction, where the solid mass adheres to the mouth, tongue, or teeth. Saliva and moisture will eventually weaken the bond, but medical attention is necessary to ensure the airway is clear.
Inhalation Risks from Vapors
While the cured adhesive is inert, the uncured liquid releases vapors that pose an inhalation hazard, particularly in small or poorly ventilated spaces. These fumes consist of cyanoacrylate monomers, which have a distinctive, acrid odor. The vapors are irritants, but they can cause a strong reaction in the eyes and respiratory system.
Exposure to these fumes can lead to immediate symptoms like watering eyes, coughing, and irritation of the nose and throat. For sensitive individuals, or with prolonged exposure in confined areas, the vapors can aggravate existing conditions or potentially cause an allergic reaction with asthma-like symptoms. It is recommended to use the adhesive in a well-ventilated space to keep the concentration of these irritating vapors low.
Physical Hazards and First Aid
The most common danger of super glue is its primary function: the rapid bonding of skin and tissue. The polymerization reaction occurs instantly upon contact with the moisture on human skin or mucous membranes. This can result in fingers, eyelids, or lips being instantly glued together, causing panic and potential tissue damage if forced apart.
A lesser-known hazard is the heat generated during the exothermic polymerization reaction, which is significantly intensified when the glue contacts porous materials like cotton or wool. If a large drop of glue soaks into a cotton shirt, the rapid reaction can generate enough heat to cause a thermal burn to the skin underneath.
First Aid
If skin becomes bonded, do not attempt to pull the area apart, as this can tear the skin. The bonded area should be immediately soaked in warm, soapy water to allow the water to slowly penetrate and weaken the bond. Acetone, found in many nail polish removers, can also be gently applied to the skin, but it should never be used near the eyes or lips.
If the eyelids are bonded together, the eye should be flushed thoroughly with warm water, and a wet compress should be applied. It is crucial never to force the eye open, as this could damage the cornea. Seek immediate medical attention, as the eye will naturally open as the moisture in the eye slowly breaks the adhesive bond, usually within one to four days.