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3. Occupational and environmental hazard assessments for the isolation, purification and toxicity testing of cyanobacterial toxins

Author

Wickramasinghe Wasantha A, Eaglesham Geoffrey K, Reardon Karen, McGregor Glenn B, Sadler Ross, Carmichael Wayne W, Stewart Ian, Seawright Alan A, and Shaw Glen R

Subjects
Industrial medicine. Industrial hygiene, RC963-969, Public aspects of medicine, RA1-1270
Abstract

Abstract Cyanobacteria can produce groups of structurally and functionally unrelated but highly potent toxins. Cyanotoxins are used in multiple research endeavours, either for direct investigation of their toxicologic properties, or as functional analogues for various biochemical and physiological processes. This paper presents occupational safety guidelines and recommendations for personnel working in field, laboratory or industrial settings to produce and use purified cyanotoxins and toxic cyanobacteria, from bulk harvesting of bloom material, mass culture of laboratory isolates, through routine extraction, isolation and purification. Oral, inhalational, dermal and parenteral routes are all potential occupational exposure pathways during the various stages of cyanotoxin production and application. Investigation of toxicologic or pharmacologic properties using in vivo models may present specific risks if radiolabelled cyanotoxins are employed, and the potential for occupational exposure via the dermal route is heightened with the use of organic solvents as vehicles. Inter- and intra-national transport of living cyanobacteria for research purposes risks establishing feral microalgal populations, so disinfection of culture equipment and destruction of cells by autoclaving, incineration and/or chlorination is recommended in order to prevent viable cyanobacteria from escaping research or production facilities.

Published
2009
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4. First Report of a Toxic Nodularia spumigena (Nostocales/ Cyanobacteria) Bloom in Sub-Tropical Australia. II. Bioaccumulation of Nodularin in Isolated Populations of Mullet (Mugilidae)

Author

Stewart, Ian, primary, Eaglesham, Geoffrey K., additional, McGregor, Glenn B., additional, Chong, Roger, additional, Seawright, Alan A., additional, Wickramasinghe, Wasantha A., additional, Sadler, Ross, additional, Hunt, Lindsay, additional, and Graham, Glenn, additional

Published
2012
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17. Use of HPLC-MS/MS to monitor cylindrospermopsin, a blue–green algal toxin, for public health purposes

Author

Eaglesham, Geoffrey K., Norris, Ross L., Shaw, Glen R., Smith, Maree J., Chiswell, Robyn K., Davis, Bradley C., Neville, Gerard R., Seawright, Alan A., and Moore, Michael R.

Abstract

Increasing reports of blooms of the blue–green alga Cylindrospermopsis raciborskii (C. raciborskii), which contains the hepatotoxic alkaloid cylindrospermopsin (CYN), have led to public health concerns in Australia. The toxicology of CYN appears complex and is still being elucidated. We have utilized the combination of sensitivity and specificity afforded by coupling high performance liquid chromatography (HPLC) to a tandem mass spectrometer (MS/MS) to produce an assay which is suitable for monitoring low CYN concentrations in water samples. Intact algal cells in the water sample are lysed by a freeze–thaw cycle. After filtration (0.45 μm filter), 110 μL is injected. The HPLC uses an Altima C18 (250×4.6 mm, 5 μm) column at 40°C. Chromatography utilizes a linear gradient from 1 to 60% methanol over 5 min, with a final isocratic stage holding at 60% methanol for 1 min. The mobile phase is buffered to 5 mM with ammonium acetate. The transition from the M+H ion (416 m/z) to the 194 m/z fragment is monitored. Linearity of this assay is 1–600 μg/L [peak area=304×CYN (μg/L)−569; r2=1.000 (n=7)]. Using a single point standard curve, total coefficients of variation were 26.4, 10.5, 12.6, and 10.7% at 0.78, 5.2, 104, and 1040 μg/L. This assay is utilized in conjunction with algal cell counts and mouse bioassays to monitor water bodies for public health purposes. The rationale used in employing these methods is discussed. ©1999 John Wiley & Sons, Inc. Environ Toxicol 14: 151–154, 1999

Published
1999
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18. Blooms of the cylindrospermopsin containing cyanobacterium, Aphanizomenon ovalisporum(Forti), in newly constructed lakes, Queensland, Australia

Author

Shaw, Glen R., Sukenik, Assaf, Livne, Adi, Chiswell, Robyn K., Smith, Maree J., Seawright, Alan A., Norris, Ross L., Eaglesham, Geoffrey K., and Moore, Michael R.

Abstract

The cyanobacterium, Aphanizomenon ovalisporum(Forti) is reported herein for the first time in Australia. Its distribution appears to be restricted to an isolated subtropical region which has distinctive water quality parameters including ready availability of nutrients and relatively high chloride and hardness levels. Blooms of A. ovalisporumin Queensland, Australia, formed a thick brown surface scum from spring to autumn in newly constructed shallow lakes. During such blooms, the water and cellular material were both found to contain cylindrospermopsin, a water soluble toxin that produced fatty livers with hepatocyte necrosis in mice similar to the toxicity produced by Cylindrospermopsis raciborskii(Wolosz.). Toxin levels in freeze‐dried A. ovalisporumare approximately 25% of those present in freeze‐dried C. raciborskii. However, A. ovalisporumappears to release more of the produced toxin into the water body than does C. raciborskii.

Published
1999
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20. Analysis of cyanobacterial toxins by hydrophilic interaction liquid chromatography-mass spectrometry.

Author

Dell'Aversano C, Eaglesham GK, and Quilliam MA

Subjects
Bacterial Toxins analysis, Chromatography, Liquid methods, Cyanobacteria chemistry, Spectrometry, Mass, Electrospray Ionization methods
Abstract

The combination of hydrophilic interaction liquid chromatography with electrospray mass spectrometry (HILIC-MS) has been investigated as a tool for the analysis of assorted toxins produced by cyanobacteria. Toxins examined included saxitoxin and its various analogues (1-18), anatoxin-a (ATX-a, 19), cylindrospermopsin (CYN, 20), deoxycylindrospermopsin (doCYN, 21), and microcystins-LR (22) and -RR (23). The saxitoxins could be unequivocally detected in one isocratic analysis using a TSK gel Amide-80 column eluted with 65% B, where eluent A is water and B is a 95% acetonitrile/water solution, both containing 2.0 mM ammonium formate and 3.6 mM formic acid. The analysis of ATX-a, CYN and doCYN required 75% B isocratic. Simultaneous determination of 1-21 was also possible by using gradient elution. HILIC proved to be suitable for the analysis of microcystins, but peak shape was not symmetric and it was concluded that these compounds are best analysed using existing reversed-phase methods. The HILIC-MS method was applied to the analysis of field and cultured samples of Anabaena circinalis and Cylindrospermopsis raciborskii. In general, the method proved quite robust with similar results obtained in two different laboratories using different instrumentation.

Published
2004
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