UPTAKE OF ARSENIC BY MUSHROOMS FROM SOIL

Graphite furnace atomic absorption spectrometry (standard addition met hod) was used to determine the total arsenic in wild-growing mushrooms after digestion with nitric acid, then with perchloric acid and in as sociated soils after digestion with mixtures of nitric and hydrofluori c acids in a microwave system. Among 83 species of mushrooms the highe st concentrations of arsenic on a dry mass basis were found in Laccari a amethystea (26-125 mg kg-l), Laccaria laccata (11-33 mg kg(-1)), The lephora terrestris (38 mg kg(-1)), Boletus cavipes (11.6 mg kg(-1)) an d Ramaria botrytis (10 mg kg(-1)). Mushroom caps of L. laccata, L. ame thystea, and B. cavipes had approximately double the arsenic concentra tions found in stems. The arsenic concentrations in caps of L. amethys tea and L. laccata were directly proportional to the concentrations in the soils. The concentrations of arsenic in the soils were in the ran ge 6.5-65 mg kg(-1). Among the 19 mushroom caps with arsenic concentra tions above the method detection limit of 0.2 mg As/kg dry mass, only L. amethystea and L. laccata had arsenic concentration ratios 'cap/soi l' higher than 1 (between 1.1 and 1.9). Thelephora terrestris had a ra tio of 2.37.