An adaptable mesocosm platform for performing integrated assessments of nanomaterial risk in complex environmental systems

Abstract

Physical-chemists, (micro)biologists, and ecologists need to conduct meaningful experiments to study the environmental risk of engineered nanomaterials with access to relevant mechanistic data across several spatial and temporal scales. Indoor aquatic mesocosms (60L) that can be tailored to virtually mimic any ecosystem appear as a particularly well-suited device. Here, this concept is illustrated by a pilot study aimed at assessing the distribution of a CeO2-based nanomaterial within our system at low concentration (1.5 mg/L). Physico-chemical as well as microbiological parameters took two weeks to equilibrate. These parameters were found to be reproducible across the 9-mesocosm setup over a 45-day period of time. Recovery mass balances of 115 ± 18% and 60 ± 30% of the Ce were obtained for the pulse dosing and the chronic dosing, respectively. This demonstrated the relevance of our experimental approach that allows for adequately monitoring the fate and impact of a given nanomaterial.

Press or pulse exposures determine the environmental fate of cerium nanoparticles in stream mesocosms

“…The uptake of nanoparticles and any effects on stream organisms will be addressed in a subsequent publication. The total amount of nanoparticles recovered (49.1% in the pulse and 41.5% in the press) was within the range of 7% to 115% in mass balance recoveries published in other studies [13,15,[45][46][47]. We feel that this percentage of recovery likely reflects variability in periphyton attached to the tiles and several compartments which were not possible to sample, such as the inside of the recirculation system, the sides of the fish cages, and insects emerging from the mesocosms throughout the experiment, each possibly carrying a small body burden of Ce.…”

“…The phenomenon of flocculation at high nanoparticle concentration relative to the DOC concentration and conversely the stabilization of suspended nanoparticles at lower nanoparticle concentrations relative to the DOC concentration has been observed in many studies of the behavior of metal‐based nanoparticles in the presence of DOC , including with CeO 2 nanoparticles in the presence of natural water even under static water conditions . It is predicted that CeO 2 nanoparticles should follow slow, first‐order sedimentation kinetics in the presence of natural organic colloids .…”

High‐Energy Resolution Fluorescence Detected X‐Ray Absorption Spectroscopy: A Powerful New Structural Tool in Environmental Biogeochemistry Sciences

“…High‐energy resolution fluorescence detected XANES was used in a recent study (Tella et al, 2015) addressing the environmental impact, (bio)distribution, and (bio)transformation of nano‐CeO 2 in realistic exposure conditions. This required the development of an adapted experimental strategy based on indoor aquatic mesocosms that virtually mimic aquatic ecosystems (Auffan et al, 2014; Tella et al, 2014). Over 4 wk, the transfer, redox transformation, and impacts of 1‐mg L −1 CeO 2 nanoparticles were determined respecting an ecologically relevant mollusc ( Planorbarius corneus ) living in a pond environment.…”

Environmental exposure of a simulated pond ecosystem to a CuO nanoparticle-based wood stain throughout its life cycle

“…at the first stages of the life cycle) 13,14 and the release of silver from commercialized nanoproducts 15 . In the current study, indoor aquatic mesocosms (60 L) were adapted to assess the exposure of ecosystems to the FP of CuO NOAA-based acryl paint (CuO_Acryl_FP) in a fashion that accommodates the control required to elucidate underlying mechanisms at various time and spatial scales 16 . In aquatic ecosystems, CuO_Acryl_FP will be controlled by physical-chemical change (aggregation, sorption of (in)organic substances, redox, etc.)…”

“…Using indoor aquatic mesocosms, this study will address the (bio)transformation, (bio)distribution and bioavailability of the released materials within different environmental compartments (e.g. water, sediments, biota), and will identify the compartments where concentrations will be the highest [16][17][18] . Such an approach is undisputable to generate reliable exposure and impact data and for their integration into environmental risk assessment models related to nanotechnologies.…”