Arsenic compounds in terrestrial biota

During the past two decades trimethylarsine oxide, the tetramethylarsonium cation, arsenobetaine, arsenocholine, arsenic-containing riboses, and arsenic-containing lipids were identified in marine organisms. Terrestrial biota appeared to be restricted to the simpler organic compounds of arsenic such as methylarsonic acid, dimethylarsinic acid, and perhaps trimethylarsine. The development of an analytical method for the identification and quantification of inorganic and organic arsenic compounds with very low detection limits (extraction, evaporation of extract, dissolution of the residue, chromatography, nebulization in a hydraulic high-pressure nebulizer, detection of arsenic in the column effluent with an inductively coupled argon plasma mass spectrometer) proved that almost all of the arsenic compounds thus far found in marine organisms are also present in terrestrial biota. The detection limits of the analytical system are so low, that arsenic compounds can be quantified in human food derived from terrestrial biota. Knowledge of arsenic compounds in food should improve the assessment of risk posed by ingested arsenic.