US EPA

516438 

Journal Article 

Determination of lead in samples of zooplankton, water, and sediments in a Mexican reservoir: Evidence for lead biomagnification in lower/intermediate trophic levels? 

Rubio-Franchini, I; Saavedra, JM; Rico-Martinez, R 

2008 

Yes 

Environmental Toxicology
ISSN: 1520-4081
EISSN: 1522-7278 

23 

4 

459-465 

English 

18214885 

10.1002/tox.20357 

BCI:BCI200800660984 

We have determined lead concentration of water, sediment, and zooplankton samples of El Niagara, a reservoir in Aguascalientes, Mexico. Our results include the first report of bioconcentration factor (BCF) obtained in an actual ecosystem (as opposed to the experimental setups in the laboratory) for a rotifer species; Asplanchna brigthwellii (BCF ca. 49 300). The BCF of this predatory zooplanktonic species (A. brigthwellii) are up to four times greater than those of two grazing zooplanktonic species (Daphnia similis and Moina micrura). In this contaminated reservoir that lacks fishes, Asplanchna, and Culex sp. together with ducks and other bigger invertebrates might represent the top predators. Our data suggest that biomagnification of lead through at least one trophic level can occur in freshwater systems. Biomagnification in A. brigthwellii might be explained in part by predation of this voracious predator on young of the herbivorous cladoceran, M. micrura. Our findings stand opposite to the current theoretical framework where lead biomagnification occurs only in lower trophic levels. (C) 2008 Wiley Periodicals, Inc. 

metal toxicity; bioconcentration factors; heavy metal toxicity; lead; accumulation; brachionus-calyciflorus; food-web; bioaccumulation; toxicity; aguascalientes; accumulation; metals; lakes