Gasoline fumes are harmful in large amounts. The poisonous ingredients in gasoline leads to serious and potentially permanent lung damage. Direct inhalation of gasoline causes carbon monoxide poisoning. In smaller doses, gasoline vapors result in nose and throat irritation, dizziness and breathing difficulties.
Gasoline contains poisonous chemicals called hydrocarbons. According to the National Institutes of Health, prolonged and intentional aspiration of gasoline fumes causes serious and potentially permanent lung damage. Exposure to small amounts of gasoline vapors when filling a car's fuel tank do not necessarily cause adverse health effects. However, the results of long-term exposure to gas fumes in a controlled environment, like a gas station, are not fully known. Gasoline has a distinctive smell that is noticeable at low levels, so potential leaks are often discovered and eliminated before harm has occurred.
The first thing to do if a person breathes an excessive amount of gasoline fumes is to get that person into fresh air as quickly as possible. Prolonged exposure may require calling an ambulance or poison control center. The practice of aspirating gasoline fumes for a stimulant effect is a form of substance abuse and is extremely dangerous. It can lead to long-term health problems, including brain, liver and kidney damage.