Gasoline, or petrol, is a transparent, yellowish liquid that serves as a fuel for internal combustion engines, but its chemical makeup is a complex and highly toxic mixture of hydrocarbons derived from crude oil. It contains volatile aromatic hydrocarbons such as benzene, toluene, ethylbenzene, and xylene (BTEX). Ingesting even a small amount of this substance constitutes a severe medical emergency that requires immediate professional assistance. The inherent toxicity and physical properties of the liquid make swallowing gasoline extremely dangerous.
The Immediate Chemical and Physical Threat
The most significant danger following the ingestion of gasoline is not systemic absorption through the stomach, but the physical entry of the liquid into the lungs, a process called pulmonary aspiration. Gasoline has extremely low viscosity, meaning it is a thin, free-flowing liquid. This property allows it to spread rapidly over large surface areas, making it easy for the substance to be accidentally inhaled into the trachea and bronchi during swallowing or gagging.
The high volatility of gasoline, meaning it easily turns into vapor at room temperature, further compounds the threat to the respiratory system. Once aspirated, the liquid spreads across the delicate surfaces of the airways and alveoli, where gas exchange occurs. The hydrocarbons act as chemical irritants, causing immediate inflammation and damage to the lung tissue.
The chemical injury involves the dissolution of lipids that make up the protective lining of the mucous membranes and the surfactant in the lungs. Surfactant reduces surface tension in the alveoli, preventing the tiny air sacs from collapsing. By dissolving this layer, gasoline causes the alveoli to collapse, leading to a breakdown of the lung’s ability to transfer oxygen into the bloodstream. This process initiates chemical pneumonitis, or lung inflammation, which is the most frequent cause of serious illness and death following ingestion.
Acute Symptoms and Critical Systemic Effects
The initial symptoms of gasoline ingestion are often centered on the respiratory system due to the rapid onset of aspiration pneumonitis. Patients may experience violent coughing, choking, and breathlessness (dyspnea) immediately after exposure. This can progress to rapid, shallow breathing (tachypnea) and hypoxemia, or low blood oxygen levels, as the lungs struggle to function.
Gastrointestinal symptoms occur as the substance passes through the digestive tract, causing direct chemical irritation of the mucous lining. An immediate burning sensation in the mouth, throat, and esophagus is typical, followed by severe abdominal pain. Vomiting can occur spontaneously, and the irritation can lead to hemorrhagic gastritis.
The central nervous system (CNS) can also be affected as the volatile hydrocarbons are absorbed into the bloodstream. Systemic absorption, particularly of compounds like benzene and toluene, causes transient CNS excitation followed by depression. Observable effects include dizziness, vertigo, and mental confusion, which may present as a staggering gait or slurred speech. In cases of large ingestion, the depression can become severe, leading to lethargy, seizures, loss of consciousness, or coma.
Emergency Protocol and Medical Intervention
Immediate action following the ingestion of gasoline must prioritize preventing further aspiration and obtaining professional medical care. Never induce vomiting, as this significantly increases the risk of the liquid passing into the lungs, which is the primary life-threatening event.
The affected person must be kept calm and immediately moved to a fresh air environment. Emergency services (911) should be called without delay, and the national toll-free Poison Help hotline (1-800-222-1222) should be contacted for expert guidance. It is helpful to provide medical personnel with the estimated amount ingested, the time of ingestion, and the patient’s current symptoms.
Medical intervention in a hospital setting is primarily supportive, as there is no specific antidote for gasoline poisoning. The initial focus is on the pulmonary system, with patients monitored closely for signs of chemical pneumonitis, which can take up to six hours to fully develop. Monitoring typically involves chest X-rays, pulse oximetry to measure blood oxygen saturation, and potentially arterial blood gas analysis.
If the patient has breathing difficulties, oxygen therapy or mechanical ventilation may be necessary to support respiratory function. Decontamination procedures like administering activated charcoal or performing gastric lavage (stomach pumping) are generally contraindicated due to the limited effectiveness of charcoal and the high risk of inducing aspiration with lavage. Patients with mild symptoms who show a clear chest X-ray and no respiratory distress are often observed for six to eight hours before being medically cleared.