The aim of the study is to develop quantitative methods for analysis of BMAA using novel derivatization techniques prior to LC-MS analysis and laser desorption. Also method application studies are to be performed both for already existing methods for BMAA quantification and the ones to be developed in the current study. Methods are supposed to be applied on food and cyanobacteria samples. Furthermore, levels of BMAA in the Baltic food web and possible aerosol transmission will be elucidated.