Mercury levels in lichens from different host trees around a chlor-alkali plant in New Brunswick, Canada.

Mercury concentrations were determined in the epiphytic lichen Hypogymnia physodes along five transects starting from a chlor-alkali plant located at Dalhousie, New Brunswick, a landfill site and a nearby electricity generating station. Lichen samples were collected from white birch (Betula papyrifera) and spruce (Picea sp.) or balsam fir (Abies balsamea).