title: Cyanotoxins: bioaccumulation and effects on aquatic animals.
abstract: Cyanobacteria are photosynthetic prokaryotes with wide geographic distribution that can produce secondary metabolites named cyanotoxins. These toxins can be classified into three main types according to their mechanism of action in vertebrates: hepatotoxins, dermatotoxins and neurotoxins. Many studies on the effects of cyanobacteria and their toxins over a wide range of aquatic organisms, including invertebrates and vertebrates, have reported acute effects (e.g., reduction in survivorship, feeding inhibition, paralysis), chronic effects (e.g., reduction in growth and fecundity), biochemical alterations (e.g., activity of phosphatases, GST, AChE, proteases), and behavioral alterations. Research has also focused on the potential for bioaccumulation and transferring of these toxins through the food chain. Although the herbivorous zooplankton is hypothesized as the main target of cyanotoxins, there is not unquestionable evidence of the deleterious effects of cyanobacteria and their toxins on these organisms. Also, the low toxin burden in secondary consumers points towards biodilution of microcystins in the food web as the predominant process. In this broad review we discuss important issues on bioaccumulation and the effects of cyanotoxins, with emphasis on microcystins, as well as drawbacks and future needs in this field of research.
authors.affiliation: Laboratory of Evaluation and Promotion of Environmental Health, Instituto Oswaldo Cruz, FIOCRUZ, Av. Brasil 4365, Manguinhos, Rio de Janeiro, RJ 21045-900, Brazil.
authors.forename: Aloysio da S
authors.initials: ADS
authors.lastname: Ferrão-Filho
authors.affiliation: Departament of Ecology and Marine Resources, Federal University of Rio de Janeiro State (UNIRIO), Av. Pasteur 458, Urca, Rio de Janeiro, RJ 22290-040, Brazil.
authors.forename: Betina
authors.initials: B
authors.lastname: Kozlowsky-Suzuki
mesh_terms: D000818:Animals; D001427:Bacterial Toxins / Q000378:metabolism* / Q000633:toxicity; D000458:Cyanobacteria / Q000472:pathogenicity*; D052998:Microcystins / Q000378:metabolism / Q000633:toxicity
chemical_list: D001427:Bacterial Toxins; D052998:Microcystins