Geochemical markers in the detection and identification of fossil fuels in waste material from an illegal landfill fire

Organic compounds, including n-alkanes, steranes, pentacyclic triterpanes, polycyclic aromatic hydrocarbons (PAHs), and alkyl aromatic hydrocarbons, often originate from industrial activities, vehicle emissions, used transformer oils, biomass combustion, and also natural organic matter. The unprotected surroundings of former industrial sites, especially those affected by fire, pose significant risks to public health and the environment, particularly soil and water. These compounds are also excellent geochemical markers for determining the material that was used to ignite the fire, including petroleum products, oils, greases, and gasoline. This study presents research findings from an illegal landfill in Sosnowiec, Poland, which caught fire in 2020, leading to the combustion of petroleum substances, plastics, and other waste. The study found PAH_sum concentrations ranging from 4.57 to 302.45 ppm in soil samples and from 3.04 to 27211.98 ppm in burnt solid waste samples, indicating significant contamination. The test results confirmed that the main sources of these pollutants in the analyzed research area were, among other things, greases, industrial oils, products from solid fuel processing, and coal waste. The use of pentacyclic triterpanes (hopanes and moretanes) seems to be the most effective diagnostic method to detect the presence of organic fossil fuels in waste samples. This research underscores the critical need to monitor and control illegal landfills to prevent fires and limit the exposure of communities and the environment to toxic pollutants. The methodologies applied here could be adopted globally to address soil and water pollution in similar contexts. By using these techniques, researchers could better interpret and manage environmental data, ultimately improving pollution control strategies worldwide.