Gasoline and other petroleum products are not among the top animal poisons, but they can cause illness if ingested or exposed to the skin. The most common petroleum products associated with illness include motor oil, gasoline, kerosene, propane and diesel.
Toxicity caused by petroleum products is based on the thinness and lightness of the product. Due to the ease of absorption, the thin, light products, such as gasoline, are more toxic than the thick, heavy products, such as motor oil.
Most petroleum products are readily absorbed from the skin and stomach. These products are irritants and cause redness and inflammation to the skin and stomach lining. If inhaled, they also cause irritation to the airways. The primary toxic agents in petroleum products are hydrocarbons, organic compounds that contain hydrogen and carbon only. The more hydrocarbons that are present, the lighter and thinner is the product.
The most common illness associated with petroleum product ingestion is burning of the mouth, throat, esophagus and stomach. This burning sensation can cause vomiting in some animals. As the animal vomits some of the petroleum can be inhaled into the airways, resulting in aspiration pneumonia. For this reason, inducing vomiting at home is not recommended. Animals that vomit on their own should be monitored closely for breathing problems. A few animals may develop serious neurologic signs including seizures, coma and death. It is possible that some of the hydrocarbons can be absorbed from the stomach into the airways, causing serious lung damage.
The amount of petroleum that needs to be ingested before signs of illness develop varies from product to product. For diesel fuel, about 18 mls (a little over 1 tablespoon) of fuel per pound of body weight needs to be ingested before the signs of diarrhea, vomiting and gastrointestinal upset are seen. For gasoline, 35 mls per pound needs to be ingested. For kerosene, 112 mls per pound needs to be ingested to reach toxic levels. After ingestion, most petroleum products are cleared from the body within 24 to 48 hours.
What to Watch For
Diagnosing petroleum ingestion can be difficult unless the owner witnessed the ingestion or exposure. If the animal vomits, the vomitus can be mixed with warm water. If petroleum is present, it will often rise to the surface. Chemical analysis of the vomitus is not typically performed due to cost and the length of time it takes to get results.
Physical examination may reveal petroleum odor to the breath or to the skin. Burns may be seen in the mouth and throat. If toxicity is from topical exposure, the skin may be red and inflamed. Recommended tests may include: