Heavy metals inParmelia sulcata collected in the neighborhood of a coal-fired power station

Abstract

The epiphytic lichenParmelia sulcata was collected in the neighborhood of a Portuguese coal-fired power station (Sines coal power station) as monitor for heavy metal air pollution. A study of the metal contents variability along 1991 and 1992 was performed. The heavy metals Ag, As, Br, Co, Cr, Fe, Hg, Sb, Se, and Zn were determined byk ₀-based instrumental neutron activation analysis. The concentrations found in 1991 and 1992 show an accumulating process of Co and Fe (≈5%/mo) and of Cr and Sb (≈7%/mo). Low accumulation is observed for Ag, Se, and Zn (≈2%/mo), and no concentration variation is observed for As, Br, and Hg. It is concluded that the metal accumulation observed is the result of the nearby ash and coal deposits.