MOBILIZATION OF METALS BY FUNGI IN HISTORIC GRAVEYARDS

Interactions among fungi, soil, and metals are at the heart of nutrient cycling in terrestrial systems. Both major and trace elements are found in soils, but the degree to which they are biologically available is influenced by chemical weathering of soil minerals by fungi. In addition to contributing to weathering, mushrooms are known to bioaccumulate metals from soil, so edible mushrooms growing on soils contaminated with toxic metals can cause harm to those who eat them. This study focuses on metal content of mushrooms and soils from cemeteries that are suspected to be contaminated with arsenic as a result of late-19th Century embalming practices. Mushrooms and soil were collected from eight cemeteries and two control areas in Lewiston, Auburn, and Sabattus, Maine and analyzed for metal content using acid digestion and ICP-OES. With particular focus on arsenic, concentrations of many metals in mushrooms are compared to concentrations of those metals in the soil on which the mushrooms were growing.