Cyanobacterial toxins, exposure routes and human health

Abstract

The production of potent toxins by bloom-, scum-and mat-forming cyanobacteria, in fresh-, brackish and marine waters, appears to be a global phenomenon. Cyanobacterial toxins can also be produced by cyanobacteria from terrestrial sources. The range and number of known cyanobacterial toxins are increasing apace as associated poisoning incidents are investigated, and increasingly powerful analytical methods are applied to complement toxicity-based studies on both natural samples and laboratory isolates of cyanobacteria. Water quality management to reduce toxic cyanobacterial mass developments, and schemes to mitigate the potential effects of cyanobacterial toxins, require an understanding of the occurrence and properties of the toxins and of the exposure routes via which the toxins present risks to health. Here, we review advances in the recognition of cyanobacterial toxins and their toxicity, and of the exposure routes with reference to human health, namely via skin contact, inhalation, haemodialysis and ingestion (the oral route).

Simultaneous determination of microcystin-LR and its glutathione conjugate in fish tissues by liquid chromatography–tandem mass spectrometry

“…Microcystins (MCs) are potent monocyclic heptapeptides produced by many members of cyanobacteria, including Microcystis, Anabaena, and Planktothrix [1,2]. They have a common moiety composed of five amino acids: 3-amino-9-methoxy-l0-phenyl-2,6,8-trimethyldeca-4,6-dienoic acid (Adda), N-methyldehydroalanine (Mdha), d-alanine, ␤-linked d-erythro-␤-methylaspartic acid and ␥-linked d-glutamic acid, and two l-amino acids as variants [3].…”

Algae in Forensic Investigations

“…Many of the filamentous, mat-forming algae of pond surfaces, particularly if they are bluegreen in color, are likely to be blue-green algae such as Anabaena (Figure 9.2A), Lyngbya, or Oscillatoria (Figure 9.2B). Many blue-green algae produce powerful dermatoxins, neurotoxins, or hepatotoxins -toxins that can make humans sick or prove fatal to livestock who have ingested or otherwise been exposed to water from a water body with a bloom (large growth) of toxic blue-greens (Hayman 1992;Codd et al 1999;Falconer and Humpage 2006). Blue-green toxins have also been implicated in certain neurodegenerative diseases of humans, with some (e.g., lytico-bodig of Guam) occurring on the scale of regional or local epidemics that have lasted decades before the root cause of the disease has been identified (Cox and Sacks 2002).…”

Analysis of microcystins by capillary high performance liquid chromatography using a polymethacrylate‐based monolithic column

“…MCs have proved to be inhibitors of serine/threonine specific protein phosphatases (PP1 and PP2A) [3,4]. They are widely recognized as a public health problem due to both their potent acute liver toxicity (LD 50 (mouse) is 50 -500 lg/kg and a mouse injected with a lethal dose dies within l -3 h), and their long-term effects as tumour promoters [5,6]. Blooms of cyanobacteria are becoming more and more prevalent as a result of the discharge of increasing amounts of nutrients such as nitrates and phosphates coming from fertilizers and domestic sewage.…”