Accumulation of several heavy metals and lanthanides in mushrooms (Agaricales) from the Chicago region

This study explored the differences in metal uptake in sporocarps of ectomy corrhizae-forming fungi relative to (1) fungal species; (2) collection loca tion; (3) differential metal uptake and variation within single-species, si ngle-area populations; and (4) mobile metal content of soil substrate for t he fungi. In addition, this study examined levels of some of the lanthanide s in these mushrooms, as lanthanide uptake in higher fungi has not been qua ntified to date. In 1995 and 1996, sporocarps from three species of ectomyc orrhizal fungi (Amanita flavorubescens, Amanita rubescens, and Russula pect inatoides) were collected from Cowles Bog, Indiana Dunes National Lakeshore (near an industrial area) and the Palos forest preserves (near a residenti al area). Soil was also collected from the Cowles Bog plots; metals were ex tracted from the soil, either with local Lake Michigan water or with nitric acid. These two extractions were meant to simulate the natural soil equili brium concentrations of soluble metals and the maximum possible effects of any fungal chelating chemicals, respectively. An inductively coupled plasma mass spectrometer was used to analyze soil extracts and nitric acid digest s of whole sporocarps for the target analytes. The metals found at elevated levels in the mushrooms included four of environmental interest (Ag, Cd, B a, and Pb) and three lanthanides (La, Ce, and Nd). Significant differences in uptake of metals were observed between A. rubescens and R. pectinatoides , while A. rubescens and A. flavorubescens were not significantly different . With regard to location, more cadmium was found in Cowles Bog collections of A. rubescens, while Pales forest A. rubescens had more of the lanthanid es and barium. Significant specimen-to-specimen variation occurred in all p opulations examined. Correlation analysis between pairs of trace elements w ithin each sporocarp population revealed strong positive correlations betwe en the lanthanides. Sporocarps concentrated more metal than was made availa ble by the lake water extraction of soil and less metal than was made avail able by the nitric acid extraction of soil. (C) 1998 Elsevier Science B.V. All rights reserved.