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
- Caustic ingestion
- Caustic eye exposure (Caustic keratoconjunctivitis)
- Caustic dermal burn
- Airbag-related burns
- Hydrofluoric acid
- Tar burn
- Cement burn
Diagnosis
- Clinical diagnosis
- Workup should be based on clinical presentation, and may include:
Management
- Immediately
- Cool tar with cold water until hardens to limit tissue damage
- Take care to avoid hypothermia
- Removal
- Case reports suggest using mild solvents like sunflower oil, butter, or mayonnaise for thin layers
- Neosporin cream with polysorbate base (not the petroleum base) dissolves tar and may be used for residual tar
- If thick layer adherent, may use diesel to remove top layers
- However, such hydrocarbons can be absorbed through burns if in contact with pt
- Thus, use diesel only for top layer and use other milder solvents for bottom layer
Disposition
- Admit to burn center for >10% TBSA or significant full thickness injury