Background Bloom-forming cyanobacteria occur globally in aquatic environments. They produce diverse bioactive metabolites, some of which are known to be toxic. The most studied cyanobacterial toxins are microcystins, anatoxin, and...
moreBackground Bloom-forming cyanobacteria occur globally in aquatic environments. They produce diverse bioactive metabolites, some of which are known to be toxic. The most studied cyanobacterial toxins are microcystins, anatoxin, and cylindrospermopsin, yet more than 2000 bioactive metabolites have been identified to date. Data on the occurrence of cyanopeptides other than microcystins in surface waters are sparse. Results We used a high-performance liquid chromatography–high-resolution tandem mass spectrometry/tandem mass spectrometry (HPLC–HRMS/MS) method to analyse cyanotoxin and cyanopeptide profiles in raw drinking water collected from three freshwater reservoirs in the United Kingdom. A total of 8 cyanopeptides were identified and quantified using reference standards. A further 20 cyanopeptides were identified based on a suspect-screening procedure, with class-equivalent quantification. Samples from Ingbirchworth reservoir showed the highest total cyanopeptide concentrations, rea...