Hydrocarbon Toxicity Workup

Updated: Feb 15, 2022
  • Author: Derrick Lung, MD, MPH, FACEP, FACMT; Chief Editor: Michael A Miller, MD  more...
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Laboratory Studies

The workup depends on the exposure. Pulse oximetry should be performed on all patients to evaluate oxygenation.

Complete blood count

Acute ingestion of benzene can result in leukocytosis. Anemia can occur as a result of intravascular hemolysis. Chronic benzene exposure may produce either acute myelogenous leukemia or aplastic anemia.

A complete blood cell count (CBC) should be ordered if there is concern for any of the above findings. However, it is not necessary to routinely obtain a CBC in all hydrocarbon exposures.


A routine basic metabolic panel should be performed to determine the blood urea nitrogen (BUN), creatinine, glucose, and electrolyte levels and permit calculation of the anion gap (see the Anion Gap calculator).

Any patient appearing intoxicated should have the serum glucose level checked expeditiously.

The anion gap will most likely be normal, but in acute toluene intoxication, an elevated anion gap can be present. The presence of an anion gap, especially if associated with a profound acidosis in a patient appearing intoxicated, however, should prompt an evaluation for other etiologies (eg, methanol, ethylene glycol, salicylates).

Acute kidney injury following massive hydrocarbon ingestion can occur but is rare.

Testing of hepatic transaminase levels should be performed, as these can be elevated following hydrocarbon ingestion (particularly the halogenated hydrocarbons).

A serum creatine kinase (CK) level should be obtained, as acute rhabdomyolysis has been reported in association with isolated hydrocarbon intoxication.

Specific diagnostic testing for hydrocarbon poisoning exists but is unlikely to be clinically helpful, as these tests are not routinely available.


Imaging Studies

Chest radiography

All symptomatic patients should have a chest x-ray performed.

Patients who are asymptomatic (eg, no coughing or signs/symptoms of respiratory distress) should not have a chest radiograph obtained immediately. Rather, asymptomatic patients should have chest radiography performed at the end of a 6-hour observation period.

See the image below.

Anteroposterior view of the chest of 14-month-old Anteroposterior view of the chest of 14-month-old boy 30 hours after ingesting lamp oil. Note the central right lower lobe infiltrate obscuring the right heart border.

Other Tests

An electrocardiogram should be obtained to assess for dysrhythmias, especially in cases of suspected hydrocarbon abuse (ie, individuals who were huffing or bagging).