Emerging health issues of cyanobacterial blooms

Abstract

Abstract. This paper describes emerging issue related to cyanobacterial dynamics and toxicity and human health risks. Data show an increasing cyanobacteria expansion and dominance in many environments. However there are still few information on the toxic species fitness, or on the effects of specific drivers on toxin production. Open research fields are related to new exposure scenario (cyanotoxins in water used for haemodialysis and in food supplements); to new patterns of co-exposure between cyanotoxins and algal toxins and/or anthropogenic chemicals; to dynamics affecting toxicity and production of different cyanotoxin variants under environmental stress; to the accumulation of cyanotoxins in the food web. In addition, many data gaps exist in the characterization of the toxicological profiles, especially about long term effects.

Impact of climate change on waterborne diseases

“…Health risks due to the toxins produced by cyanobacteria, photosynthetic prokaryotes diffuse in all the habitats, especially the aquatic ones, have been extensively addressed in this same issue of Annali dell'Istituto Superiore di Sanità by Manganelli et al, p. 415 [99]. Briefly, cyanotoxins have different toxicological profiles, and target different organs.…”

“…Several environmental factors affect their production, but mechanisms are still unknown. Humans can be exposed to cyanotoxins via ingestion (drinking and bathing water, through aquatic food chain), via aerosol and via parenteral, if surface contaminated water is used for haemodialysis [99]. Climate changes effects will be summed up with the effects of other environmental variables on cyanobacterial fitness and toxicity, with different outcomes, depending on the species/strain and the environment (i.e.…”

Cyanobacteria and microcystin contamination in untreated and treated drinking water in Ghana

“…(Bláha et al, 2009;Van Apeldoorn et al, 2007). Their acute effetcs are primarily manifested in liver but MCs have been shown to induce gastrointestinal and renal damage or neurological symptoms as well (Manganelli et al, 2012). Chronic exposures to MCs have been linked to tumor promoting and carcinogenic effects which is based on laboratory animal and in vitro experiments (Svircev et al, 2010) and supported also by results of epidemiologic studies of human population consuming drinking water contaminated by these cyanotoxins (Fleming et al, 2002;Svircev et al, 2009Svircev et al, , 2013Svircev et al, , 2014Ueno et al, 1996;Yu et al, 1995;Zhou et al, 2002).…”

“…Microcystins (MCs) are probably the most frequently found cyanotoxins which can be produced by various cyanobacterial genera including water bloom-and scum-forming planktonic cyanobacteria such as Dolichospermum (formerly Anabaena), Microcystis or Planktothrix (Manganelli et al, 2012). Cyanobacteria representing these genera have been previosly identified in Ghanaian water reservoirs along with other cyanobacterial species potentially producing MCs (Addico et al, 2006(Addico et al, , 2009(Addico et al, , 2017.…”

“…MCs are therefore regarded as human health hazard. Exposure of human beings to MCs can occur via different routes, such as recreational and sport activities in contaminated water, consumption of contaminated fish products or food supplements, and consumption of contaminated drinking water (Manganelli et al, 2012). The World Health Organization (WHO) set a provisional guideline limit of 1 µg L -1 of MC-LR in drinking water (WHO, 1998).…”