Release of polycyclic aromatic compounds into a Mediterranean creek (Catalonia, NE Spain) after a forest fire

• Published in: Water research (Oxford) 2007-05, Vol.41 (10), p.2171-2179
• Main Authors: Vila-Escalé, M., Vegas-Vilarrúbia, T., Prat, N.
• Format: Article
• Language: English
• Subjects: Absorbance; Applied sciences; aromatic compounds; bioaccumulation; carbon; Conservation of Natural Resources; dissolved organic carbon; Exact sciences and technology; Fires; Fluorescence; Fresh Water - analysis; gas chromatography; Inorganic Chemicals - analysis; leaching; Mediterranean Region; Mediterranean stream; Organic carbon; Organic Chemicals - analysis; organic compounds; Other industrial wastes. Sewage sludge; Pollution; Polycyclic aromatic compounds (PAC); polycyclic aromatic hydrocarbons; Polycyclic aromatic hydrocarbons (PAH); Polycyclic Aromatic Hydrocarbons - isolation & purification; rain; Spain; streams; surface water; temporal variation; Wastes; water erosion; water pollution; Water treatment and pollution; wildfires
• ISSN: 0043-1354; 1879-2448
• DOI: 10.1016/j.watres.2006.07.029

Wildfires produce polycyclic aromatic compounds (PACs), among which polycyclic aromatic hydrocarbons (PAHs) are of environmental concern. After a fire affecting a Mediterranean creek, we studied the distribution and short-term permanence of PACs and of 16 priority PAH pollutants in the aquatic environment. PACs were traced through absorbance and fluorescence emissions and organic carbon concentrations. PAHs were analysed by gas chromatography. High TOC/DOC concentrations and fluorescence/absorbance values reflected abnormal inputs of fire-induced aromatic compounds. Their concentrations decreased gradually but showed sporadic peaks after precipitation. Fifteen months later, values still surpassed background levels. Initially concentrations of individual and total PAH species of the dissolved, particulate and sediment phases were increased. Then they fluctuated with new PAH inputs related with runoff, leaching and soil erosion following precipitation events. All PAH concentrations approached background levels 15 months after the fire, and never reached values of toxicological concern. However, some bioaccumulation may have occurred.