As(III), from As2O3 dissolved in 4 g L1 NaOH ; As(V), from Na2HAsO47H2O
dissolved in water; MA, prepared from (CH3)AsO(ONa)26H2O dissolved in water; DMA, prepared from
(CH3)2AsNaO23H2O dissolved in water.
Arsenocholine (AC) from (CH3)3As+(CH2) CH2OHBr was supplied
by the ‘‘Service Central d’Analyse’’ and trimethylarsine oxide (TMAO) was prepared from
(CH3)3AsO (Argus Chemicals, Vernio, Italy) dissolved in water.