P. cretica extract, m/z traces of As-PC complexes measured by ESI-MS and m/z 75 (As) measured by ICP-MS. Separation, MeOH/formic acid gradient on C18 ODS2 column (*, at m/z 422.5 this signal is not identical with As(III)-PC3(2+) analysis of retention time, and spectra show it to be an unknown organic species; *, unknown species; #, species identified as mentioned in trace).