Tar burn

Background

  • Tar is a product of the distillation of coal.[1]
    • Asphalt (now more commonly used than tar) and tar are both forms of bitumen
  • Currently used mainly for roofing and road paving
    • When used for these purposes, tar/asphalt is heated to between 140-190°C (for paving) and 210-270°C (for roofing)[1]
    • Injuries limited almost exclusively to occupational exposure in these fields
  • Tar/asphalt is highly viscous and sticks to skin, making it difficult to remove and leading to more severe burns
  • Tar itself is sterile, but dead tissue underneath is not

Clinical Features

  • Viscous black substance on skin in setting of history of working with coal tar or asphalt
    • May be hardened or still relatively fluid on presentation to ED

Differential Diagnosis

Caustic Burns

Evaluation

  • Clinical diagnosis
  • Workup should be based on clinical presentation, and may include:
    • VBG, CBC, chem, total CK
    • CXR
    • ECG
    • Urinalysis (assess for myoglobinuria)
    • Serial assessments for compartment syndrome

Management

  • Immediate treatment
    • Cool tar with cold water until hardened to stop burning and limit tissue damage
    • Take care to avoid hypothermia
  • Removal of tar/asphalt (unless small area, will generally occur in inpatient setting)
    • Needs to be dissolved as manual debridement of hardened tar/asphalt damages underlying tissue[2]
    • The best solvents are chemically similar to tar/asphalt ("like dissolves like") - suggested agents include baby oil, sunflower oil, butter, and mayonnaise[2][1]
    • Neosporin ointment has a petroleum base and is successful at slowly dissolving tar/asphalt (may also help prevent infection)[1]
    • Mineral oil has also been identified as a safe, non-toxic, and effective means of dissolving tar/asphalt[3]

Disposition

  • Admit or transfer to burn center for:
    • >10% TBSA (>5% for full thickness injury)
    • Burns of face, eyes, ears, genitalia, joints
    • Circumferential burns
    • Airway involvement
    • Significant comorbidity

See Also

References

  1. 1.0 1.1 1.2 1.3 Bosse GM, et al. Hot asphalt burns: a review of injuries and management options. Am J Emerg Med. 2014 Jul;32(7):820.e1-3.
  2. 2.0 2.1 Iuchi M, et al. The comparative study of solvents to expedite removal of bitumen. Burns. 2009 Mar;35(2):288-93.
  3. Carta T, et al. Use of mineral oil Fleet enema for the removal of a large tar burn: a case report. Burns. 2015 Mar;41(2):e11-4.