Effect of natural organic matter on cerium dioxide nanoparticles settling in model fresh water.
Chemosphere
; 81(6): 711-5, 2010 Oct.
Article
em En
| MEDLINE
| ID: mdl-20728203
ABSTRACT
The ecological risk assessment of chemicals including nanoparticles is based on the determination of adverse effects on organisms and on the environmental concentrations to which biota are exposed. The aim of this work was to better understand the behavior of nanoparticles in the environment, with the ultimate goal of predicting future exposure concentrations in water. We measured the concentrations and particle size distributions of CeO(2) nanoparticles in algae growth medium and deionized water in the presence of various concentrations and two types of natural organic matter (NOM). The presence of natural organic matter stabilizes the CeO(2) nanoparticles in suspension. In presence of NOM, up to 88% of the initially added CeO(2) nanoparticles remained suspended in deionized water and 41% in algae growth medium after 12d of settling. The adsorbed organic matter decreases the zeta potential from about -15 mV to -55 mV. This reduces aggregation by increased electrostatic repulsion. The particle diameter, pH, electric conductivity and NOM content shows significant correlation with the fraction of CeO(2) nanoparticles remaining in suspension.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Poluentes da Água
/
Cério
/
Nanopartículas Metálicas
/
Água Doce
Tipo de estudo:
Prognostic_studies
/
Risk_factors_studies
Idioma:
En
Revista:
Chemosphere
Ano de publicação:
2010
Tipo de documento:
Article
País de afiliação:
Holanda