New Measurements of Cyanobacterial Toxins in Natural Waters Using High Performance Liquid Chromatography Coupled to Tandem Mass Spectrometry

Abstract

The presence and levels of the cyanobacterial toxins microcystin-LR, anatoxin-a, and cylindrospermopsin were measured in various Wisconsin waters where algal nuisance or bloom conditions were noted. Out of 74 samples analyzed, 36 had detectable levels of microcystin-LR (49%), and four had detectable levels of anatoxin-a (5%). Cylindrospermopsin, the toxin produced by Cylindrospermopsis (a warm water species that has been moving its range northward, including to Wisconsin), was not detected in the field samples tested. Concentrations of microcystin-LR ranged from 1.2 to 7600 microg L(-1). Anatoxin-a ranged from 0.68 to 1750 microg L(-1), which is the highest concentration reported from around the world. Cyanobacterial toxins, because of their high potency, deserve continued scrutiny by resource managers and public health officials responsible for recreational waters.

Co-occurrence of microcystin and anatoxin-a in the freshwater lake Aydat (France): Analytical and molecular approaches during a three-year survey

“…Samples were considered positive for anatoxin-a detection when all 6 fragments obtained from the 166 ion MS/MS spectra were detected. Hedman et al, 2008;Graham et al, 2010;Li et al, 2010). The co-occurrence of these two toxins in lakes befalls in a wide range of cyanobacterial communities: most of them comprise Anabaena, but also Microcystis, Aphanizomenon, Planktothrix, Oscillatoria, or Pseudanabaena.…”

“…Nevertheless, a growing number of studies report the co-occurrence of several toxins in cyanobacterial blooms over the world (Park et al, 1998;Pawlik-Skowroń ska et al, 2004;Ballot et al, 2005;Hedman et al, 2008;Graham et al, 2010;Li et al, 2010), emphasizing the need to monitor several toxins in cyanobacterial blooms.…”

Microcystin in Missouri reservoirs

“…Occurrence and concentrations were similar across years, with approximately 50% of reservoirs sampled having detectable MC each summer (Table 4). Widespread occurrence with relatively few large values is characteristic of regional MC studies worldwide (Chorus and Bartram 1999, Graham et al 2004, Boyer 2007, Williams et al 2007, Hedman et al 2008, a consequence of extreme temporal and spatial variability in MC concentrations (Lindholm 1991, Kotak et al 1995, Welker et al 2003. Among reservoirs with MC maxima ≥1µg/L, 73% had detectable MC each summer, indicating seasonal inventory studies can identify reservoirs with potential for toxin production.…”

“…Potential CYL producers, including Anabaena, Aphanizomenon and Cylindrospermopsis, can dominate summer algal assemblages in Missouri reservoirs (Graham et al 2006a, Jones et al 2008a, but the toxin was detected in few samples and always at concentrations <1 µg/L. In most of the United States, CYL occurs relatively infrequently (<10% of samples) and when detected usually at concentrations <1 µg/L (Boyer 2007, Hedman et al 2008, although in Florida CYL has occurred in up to 30% of samples (Williams et al 2007) and at concentrations as large as 200 µg/L (Burns 2008).…”

“…Regional studies indicate MC occurs frequently in the Midwestern United States and may reach concentrations of human health concern (McDermott et al 1995, Dodds 1996, Graham et al 2004, Hedman et al 2008, Lindon and Heiskary 2008. Whereas several studies in the United States have assessed regional patterns in MC occurrence (McDermott et al 1995, Dodds 1996, Zimba and Grimm 2003, Graham et al 2004, Boyer 2007, Williams et al 2007, Hedman et al 2008, Lindon and Heiskary 2008, few have evaluated frequency of occurrence during successive summer seasons. Likewise, few regional studies have developed empirical relations between environmental factors and MC concentration.…”