Bioaccumulation of microcystins in seston, zooplankton and fish: A case study in Lake Zumpango, Mexico
Por:
Zamora-Barrios C.A., Nandini S., Sarma S.S.S.
Publicada:
1 ene 2019
Resumen:
Cyanotoxins from toxic blooms in lakes or eutrophic reservoirs are harmful to several organisms including zooplankton, which often act as vectors of these secondary metabolites, because they consume cyanobacteria, bioaccumulate the cyanotoxins and pass them on along the food chain. Microcystins are among the most commonly found cyanotoxins and often cause zooplankton mortality. Although cyanobacterial blooms are common and persistent in Mexican water bodies, information on the bioaccumulation of cyanotoxins is scarce. In this study we present data on the bioaccumulation of cyanotoxins from Planktothrix agardhii, Microcystis sp., Cylindrospermopsis raciborskii and Dolichospermum planctonicum blooms in the seston (suspended particulate matter more than 1.2 µm) by zooplankton and fish (tilapia (Oreochromis niloticus) and mesa silverside (Chirostoma jordani) samples from Lake Zumpango (Mexico City). The cyanotoxins were extracted from the seston, zooplankton and fish tissue by disintegration using mechanical homogenization and 75% methanol. After extraction, microcystins were measured using an ELISA kit (Envirologix). Concentration of microcystins expressed as equivalents, reached a maximum value of 117 µg g -1 on sestonic samples; in zooplankton they were in the range of 0.0070–0.29 µg g -1 . The dominant zooplankton taxa included Acanthocyclops americanus copepodites, Daphnia laevis and Bosmina longirostris. Our results indicate twice the permissible limits of microcystins (0.04 µg kg -1 d -1 ) for consumption of cyanobacterial products in whole fish tissue of Chirostoma jordani. The data have been discussed with emphasis on the importance of regular monitoring of water bodies in Mexico to test the ecotoxicological impacts of cyanobacterial blooms and the risk that consumption of products with microcystins could promote. © 2019 Elsevier Ltd
Filiaciones:
Zamora-Barrios C.A.:
Posgrado en Ciencias del Mar y Limnología, Universidad Nacional Autónoma de México, Av. Ciudad Universitaria 3000, C.P. 04510, Coyoacán, Ciudad de México, Mexico
Nandini S.:
Laboratory of Aquatic Zoology, Division of Research and Postgraduate Studies, National Autonomous University of Mexico, Campus Iztacala, Av. de Los Barrios No. 1, C.P. 54090, Los Reyes, Tlalnepantla, State of Mexico, Mexico
Univ Nacl Autonoma Mexico, Div Res & Postgrad Studies, Lab Aquat Zool, Campus Iztacala,Ave Los Barrios 1, Tialnepantla 54090, State Of Mexico, Mexico
Sarma S.S.S.:
Laboratory of Aquatic Zoology, Division of Research and Postgraduate Studies, National Autonomous University of Mexico, Campus Iztacala, Av. de Los Barrios No. 1, C.P. 54090, Los Reyes, Tlalnepantla, State of Mexico, Mexico
Univ Nacl Autonoma Mexico, Posgrad Ciencias Mary & Limnol, Ave Ciudad Univ 3000, Mexico City 04510, DF, Mexico
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