posted on 2012-10-16, 00:00authored byAlina
D. Burchardt, Raquel N. Carvalho, Angelica Valente, Paola Nativo, Douglas Gilliland, Cesar P. Garcìa, Rosanna Passarella, Valerio Pedroni, François Rossi, Teresa Lettieri
The aim of the present study was to investigate the effect
of silver
nanoparticles (AgNP) of different sizes toward two primary producer
aquatic species. Thalassiosira pseudonana and Synechococcus sp. have been selected as representative models
for the lower trophic organisms in marine and freshwater habitats,
respectively. Time-dependent cellular growth was measured upon exposure
to both AgNP and silver nitrate (AgNO3). In addition, AgNP
behavior in freshwater and marine waters has been followed by CPS
disc centrifuge, in the time frame of AgNP exposure studies, and the
kinetic release of silver from AgNP of different sizes was measured
by dialysis and inductively coupled plasma mass spectrometry (ICP-MS).
The combination and interpretation of all these data suggest that
a shared effect of AgNP and released silver was responsible for the
toxicity in both organisms. Furthermore, the toxic effects induced
by AgNP exposure in the present study seem to result from a mixture
of parameters including aggregated state, size of the AgNP, stability
of the preparation, and speciation of the released silver.