Antifreeze is a common fluid used in vehicle engines to protect the cooling system from freezing and overheating. This coolant contains chemicals that can pose a risk to human health, especially when its vapors are released into the air. Antifreeze fumes can make you sick, though the severity depends on the chemical makeup of the product and the extent of the exposure. Understanding the components and conditions that create dangerous fumes is key to mitigating this health risk.
What Makes Antifreeze Toxic
The potential for illness stems from the primary ingredients in antifreeze, typically one of two glycol compounds. The most common and hazardous component is ethylene glycol (EG), which is highly effective but also a poison. Propylene glycol (PG) is the less toxic alternative, often used in “safer” or pet-friendly products.
EG itself is not the most dangerous substance; toxicity arises after it enters the body. Enzymes metabolize EG into increasingly toxic byproducts, including glycolic acid and oxalic acid. The accumulation of these organic acids leads to severe metabolic acidosis, disrupting bodily function. Oxalic acid also forms calcium oxalate crystals, which deposit in the kidneys and can cause acute kidney failure.
How Fume Exposure Occurs
The risk of inhaling fumes relates to ethylene glycol’s chemical properties. EG has a low vapor pressure, meaning it does not readily evaporate into the air at standard room temperature. Therefore, substantial exposure to true EG vapor is unlikely in a typical, well-ventilated environment.
Dangerous exposure requires conditions that actively transform the liquid into a breathable form. The most common scenario is when antifreeze is aerosolized or heated to high temperatures, such as in a leaky or overheating engine. A cracked radiator or hose can spray a fine mist, or aerosol, of the coolant into the air, which is easily inhaled. Vapors and aerosols can also accumulate to dangerous concentrations when working in poorly ventilated, confined spaces, like a closed garage.
Recognizing Inhalation Symptoms
Inhaling concentrated antifreeze vapors or aerosols directly irritates the mucous membranes and the upper respiratory tract. Exposure above 80 parts per million (ppm) can lead to respiratory discomfort and coughing.
The symptoms of inhalation often overlap with the initial stages of ingestion poisoning, which affects the central nervous system (CNS). Early signs include a feeling of intoxication, similar to alcohol consumption, along with dizziness, headache, and fatigue. More pronounced CNS effects may involve slurred speech and a lack of coordination. If exposure is high enough, symptoms can progress to profound nausea, vomiting, disorientation, or even stupor. While inhalation is typically less severe than ingestion, prolonged exposure can still lead to systemic toxicity, requiring prompt medical attention for respiratory depression or metabolic acidosis.
Safe Handling and Emergency Steps
Preventing fume exposure involves controlling the conditions that create vapors and aerosols. Always ensure your work area is well-ventilated when handling antifreeze, especially near a running or recently stopped engine. Avoid opening a hot cooling system, as pressurized coolant can spray or release steam and vapor. Wear appropriate personal protective equipment, such as chemical-resistant gloves and safety goggles, to prevent skin and eye contact during fluid changes.
In the event of fume inhalation, immediately move the exposed person to an area with fresh air. If eye or throat irritation occurs, flush the irritated areas with water for at least 15 minutes. If symptoms persist, or if high exposure leads to dizziness, confusion, or difficulty breathing, seek medical help immediately. For any suspected severe exposure or accidental ingestion, contact the Poison Help hotline at 1-800-222-1222 for expert guidance.