ARSENIC COMPOUNDS IN TERRESTRIAL ORGANISMS .2. ARSENOCHOLINE IN THE MUSHROOM AMANITA-MUSCARIA

Arsenic compounds were identified and quantified in the mushroom Amani ta muscaria, collected close to a facility that had roasted arsenic or es, The powdered dried mushrooms were extracted with methanol/water (9 :1), the extracts were concentrated and the concentrates were dissolve d in water, The resulting solutions were chromatographed on anion-exch ange, cation-exchange and reversed-phase columns, Arsenic was detected on-line with an ICP-MS detector equipped with a hydraulic high-pressu re nebulizer, Arsenite, arsenate, dimethylarsinic acid and the tetrame thylarsonium cation were minor arsenic compounds (similar to 2% each o f the total 22 mg kg(-1) dry mass), and arsenobetaine, arsenocholine ( similar to 15% each) and several unidentified arsenic compounds (simil ar to 60%) were the major arsenic compounds in Amanita muscaria. The p resence of arsenocholine (detected for the first time in a terrestrial sample) was ascertained by matching retention times in the anion-exch ange, cation-exchange and reversed-phase chromatograms with the retent ion time of synthetic arsenocholine bromide and chromatographing extra cts spiked with arsenocholine bromide. (C) 1997 by John Wiley & Sons, Ltd.