Cyanotoxin mixtures and taste-and-odor compounds in cyanobacterial blooms from the Midwestern United States.
The mixtures of toxins and taste-and-odor compounds present during cyanobacterial blooms are not well characterized and of particular concern when evaluating potential human health risks. Cyanobacterial blooms were sampled in twenty-three Midwestern United States lakes and analyzed for community composition, thirteen cyanotoxins by liquid chromatography/mass spectrometry and immunoassay, and two taste-and-odor compounds by gas chromatography/mass spectrometry. Aphanizomenon, Cylindrospermopsis and/or Microcystis were dominant in most (96%) blooms, but community composition was not strongly correlated with toxin and taste-and-odor occurrence. Microcystins occurred in all blooms. Total microcystin concentrations measured by liquid chromatography/mass spectrometry and immunoassay were linearly related (r(s) = 0.76, p < 0.01) and LC/MS/MS concentrations were lower than or similar to ELISA in most (85%) samples. Geosmin (87%), 2-methylisoborneol (39%), anatoxin-a (30%), saxitoxins (17%), cylindrospermopsins (9%), and nodularin-R (9%) also were present in these blooms. Multiple classes of cyanotoxins occurred in 48% of blooms and 95% had multiple microcystin variants. Toxins and taste-and-odor compounds frequently co-occurred (91% of blooms), indicating odor may serve as a warning that cyanotoxins likely are present. However, toxins occurred more frequently than taste-and-odor compounds, so odor alone does not provide sufficient warning to ensure human-health protection.
Graham
Jennifer L
JL
United States Geological Survey, Kansas Water Science Center, 4821 Quail Crest Place, Lawrence, Kansas 66049, USA. jlgraham@usgs.gov
Loftin
Keith A
KA
Meyer
Michael T
MT
Ziegler
Andrew C
AC
D001427:Bacterial Toxins / Q000032:analysis*; D000458:Cyanobacteria / Q000737:chemistry* / Q000254:growth & development; D004797:Enzyme-Linked Immunosorbent Assay; D015146:Midwestern United States; D009812:Odorants; D013649:Taste
D001427:Bacterial Toxins