Polycyclic Aromatic Hydrocarbons in Liquid Fuels

Polycyclic aromatic hydrocarbons (PAHs) are a group of aromatic compounds containing two or more fused aromatic rings. In liquid fuels, they are considered undesirable components, as some PAHs have proven carcinogenic effects, and their combustion contributes to the formation of harmful particulate matter, negatively impacting both the environment and human health. Among the liquid fuels discussed in this article, PAH content is monitored only in selected diesel-type fuels. The most commonly used diesel fuel in the Czech Republic and across the EU is B7 diesel, which contains a maximum of 7 % (V/V) bio-component and must comply with the requirements of the EN 590 standard. This standard sets a maximum PAH content of 8 % (m/m) for B7 diesel. For aviation fuels and automotive gasolines, no specific PAH limits are defined; the relevant standards only specify maximum permissible levels of total aromatic hydrocarbons.