Mass fragmentographic estimation of trimethylarsine oxide in aquatic organisms

An analytical method for quantitative and qualitative analysis of trimethylarsine oxide (TMAO) in biological material has been developed in our laboratorries. By use of mass fragmentographic technique together with synthetic deuterium labelled trimethylarsine oxide as internal standard it is possible to compensate for chemical and physical interactions. TMAO is, besides arsenobetaine and arsenocholine, an arsenic compound identified in fish. Low levels of TMAO are found in fresh fish, and elevated concentrations seem to be common in stored and frozen fish.