Biomarker compounds in ash from coal combustion in domestic furnaces (Upper Silesia Coal Basin, Poland)

► We investigate organic compounds in coal ash from domestic furnaces. ► Two types of organic compounds in ash extracts: from source coal and heat-originated. ► Biomarkers show recognizable distributions of source bituminous coal. ► Some biomarkers distributions are partially affected by heat. ► Temperature and oxygen level influence biomarker distributions.