Ingestion, inhalation, or direct skin contact with petroleum, petroleum condensate, gasoline, diesel fuel, kerosene, crude oil, or other hydrocarbon mixtures can cause illness and occasionally death in animals. Pipeline breaks, accidental release from storage tanks, and tank car accidents may contaminate land and water supplies. Animals may have access to open or leaky containers of fuel or other hydrocarbon materials.
Crude oil and gasoline contain varying amounts of aromatic hydrocarbons including benzene, toluene, ethyl-benzene, and xylene. These compounds, if ingested or inhaled in sufficient amounts, can have short- or longterm effects different from those caused by other hydrocarbons that make up most oil and gas products. Benzene, for example, is a known carcinogen at high levels of exposure and may damage red blood cells. Toluene can cause severe neurologic signs and damage. Gasoline, naphtha, and kerosene can damage lung tissue. Gasoline and naphtha may cause vomiting. Older formulations of lubricating oils and greases can be particularly dangerous because of toxic additives or contaminants (for example, lead).
Petroleum fractions have been used as pesticides for ticks and mites for many years. Small quantities applied to the skin cause few or no harmful effects, but large quantities and prolonged exposure can cause severe reactions. If their fur becomes contaminated, both dogs and cats can ingest petroleum products during grooming. Dogs can also ingest petroleum products directly when they are left in open containers. Animals confined to poorly ventilated areas where petroleum products have been used or stored can breathe in these compounds.
Petroleum hydrocarbon poisoning can involve the lungs, skin, gastrointestinal system, or the central nervous system. In most cases of ingestion, no signs are seen. Aspiration pneumonia (sometimes caused during vomiting) is usually the most serious consequence of ingestion of these materials. Severe bloat is not consistently seen but can cause death very shortly after ingestion of gasoline or naphtha. Loss of appetite and mild depression begin in about a day and last 3 to 14 days depending on dose and content. Blood sugar can be low for several days after ingestion. These signs and weight loss may be the only signs in animals that do not bloat or draw the oil into their lungs. Some animals (ruminants) develop a longterm wasting condition.
The feces of ruminants may become dry and formed several days after ingestion of kerosene or lighter hydrocarbon substances. In contrast, heavier hydrocarbon mixtures tend to cause emptying of the bowels. Oil may be found in feces up to 2 weeks after ingestion. Regurgitated or vomited oil may be seen on the muzzle and lips. Signs can include excitability or depression, shivering, head tremors, visual problems, and lack of coordination. Sudden, severe pneumonia with coughing, rapid and shallow breathing, reluctance to move, head held low, weakness, oily nose discharge, and dehydration are seen in some animals that breathe highly volatile mixtures into their lungs; death usually is seen within days. Respiratory signs may be limited to difficulty breathing shortly before death in animals that draw heavier hydrocarbons into their lungs.
Your veterinarian can confirm the diagnosis by the signs, along with analysis of gastrointestinal contents, lung, liver, kidney, and the suspected source.
If the animal has bloated, the pressure should be released by passing a stomach tube if necessary to save the animal’s life. However, passing a stomach tube dramatically increases the risk of drawing the substance into the lungs. If the animal has not bloated, medications are given to cause emptying of the bowels, but there is no evidence that they improve prognosis. In dogs and cats, vomiting should not be induced, to avoid the risk of drawing the substance into the lungs. Activated charcoal can be used.
Animals with respiratory problems may need broad-spectrum antibiotic treatment. Treatment of aspiration pneumonia associated with petroleum products is rarely effective, and the prognosis is poor. This is because it is usually several days before signs appear, which delays the start of treatment. In the case of skin exposure, the skin should be washed gently (no brushing or rubbing) with soap or mild detergents and large amounts of cool water. Further treatment is supportive, depending on the signs.
Petroleum hydrocarbon poisoning can be avoided only by preventing access. These substances must be stored properly, and fencing around high-risk petroleum facilities must be well maintained.