Toxicity and Toxin Composition of Microcystis aeruginosa from Wangsong Reservoir

Abstract

The increasing world population, resulting in increased anthropogenic water pollution, is negatively impacting the limited available water resources. In South Korea, this similarly affects the water quality of reservoirs. As water is a basic necessity for life, water quality monitoring is essential but typically does not include toxicity testing. However, as toxic bloom event frequencies are increasing, this previously neglected aspect becomes pertinent. Therefore, in the present study, the toxin composition and toxicity of a Microcystis aeruginosa strain isolated from a persistent bloom in lake Wangsong, South Korea, was investigated. Methods A combination of bioassays and chemical analysis was used for this purpose. The bioassay species included terrestrial and aquatic plants, an alga, a rotifer, a tubificid annelid, and crustaceans, representing various trophic levels. Results The strain was found to produce microcystin-LR,-RR, and YR, as well as β-N-methylamino-L-alanine. The bioassays indicated that the primary producers were less sensitive to the crude extract. Conclusion The presence of absence of a visible cyanobacterial bloom is also not an indication of the toxins that may be present in the afflicted waters, and thus does not predict exposure risk. Similarly, the presence and absence of toxins and mixtures thereof does not indicate the ecological effect. Therefore, it would be advantages to include toxicity testing into routine water testing regimes to better understand the impact of harmful algal blooms.

Presence of Cyanotoxins in a Mexican Subtropical Monomictic Crater Lake

“…Other yet unknown cyanobacterial co-occurring metabolites might be the cause, or microorganisms attached to the mucilage. Another metabolite not linked to the above-mentioned symptoms, but of human health concern, is the β-N-methylamino-41 L-alanine (BMAA), which may be also present in the lake, since this amino acid has been suggested to be a causative agent involved in several neurodegenerative diseases [54] and has been found in M. aeruginosa [55].…”

Determining the Exposure Pathway and Impacts of Microcystis on Threadfin Shad, Dorosoma petenense, in San Francisco Estuary

“…Blooms can produce natural toxins that promote liver tumors, neural toxicity, and developmental toxicity (International Agency for Research on Cancer 2006; Downing et al 2011; Zegura et al 2011; Zanchett and Oliveira‐Filho 2013). These natural toxins include lipopolysaccharides, neurotoxin β‐methylamino‐L‐alanine (Cox et al 2005; Downing et al 2011; Esterhuizen‐Londt et al 2018), and the metabolite, microcystin. Microcystins have been found to cause impaired cellular function, lipidosis, sinusoidal congestion, and/or necrosis in the liver of common carp, Cyprinus carpio (Drobac et al 2016), rainbow trout, Oncorhynchus mykiss (Tencalla et al 1994), threadfin shad, Dorosoma petenense , (Acuña et al 2012b) and medaka fish, Oryzias latipes (Mezhoud et al 2008; Deng et al 2010).…”