Distribution, Bioaccumulation, Trophic Transfer, and Influences of CeO₂ Nanoparticles in a Constructed Aquatic Food Web

Abstract

In view of the final destination of nanomaterials, the water system would be an important sink. However, the environmental behavior of nanomaterials is rather confusing due to the complexity of the real environment. In this study, a freshwater ecosystem, including water, sediment, water lettuce, water silk, Asian clams, snails, water fleas, Japanese medaka, and Yamato shrimp, was constructed to study the distribution, bioaccumulation, and potential impacts of CeO nanoparticles (CeO NPs) via long-term exposure. The results demonstrated most of the CeO NPs deposited in the sediment (88.7%) when the partition approached to the constant 30 days later. The bioaccumulated Ce in six tested biota species was negatively correlated with its trophic level, showing no biomagnification of CeO NPs through this food web. CeO NP exposure induced visual abnormalities in hydrophytes, including chlorophyll loss in water silk and water lettuce, ultrastructural changes in pyrenoids of water silk, and root elongation in water lettuce. The generation of hydroxyl radical (·OH) and cell-wall loosening induced by CeO NP exposure might mediate the root growth in water lettuce. The findings on the environmental behavior of CeO NPs in water system have provided useful information on the risk assessment of nanomaterials.

Cellular Uptake of Few-Layered Black Phosphorus and the Toxicity to an Aquatic Unicellular Organism

“…It is widely known that reactive oxygen species (ROS) play an essential role in regulating various physiological functions of living organisms . Previous studies suggested that overproduction of ROS could lead to oxidative stress and thus harm lipids, proteins, and DNA, causing cell membrane damage, which is a well-known link to nanomaterial-induced cytotoxicity. − Herein, ROS generated by T. thermophila cells exposed to BP (0–10 μg/mL) was measured after 0.5 h exposure by increasing DCF fluorescence. The results are expressed as the fold change of ROS production compared to the control ( T. thermophila cells unexposed to BP).…”

Potential Hazard of Lanthanides and Lanthanide-Based Nanoparticles to Aquatic Ecosystems: Data Gaps, Challenges and Future Research Needs Derived from Bibliometric Analysis

“…These studies exposed bivalves [33,[53][54][55][56], crayfish [57], chironomids [50], and rooted aquatic plants [50] to Ln ions or their complexes. Only one study concerned Ln-based NPs (CeO 2 ) [58] examining accumulation in a food web that included bivalves, snails, and benthic shrimps. As a rule, the groups of organisms that were mostly used in the bioaccumulation studies were macrophytes (28%) and bivalves (26% of papers; Figure 5).…”

“…Indeed, even biodilution of Ln has been observed in natural ecosystems [59,63]. For example, the Ce concentrations were lower in higher food chain level (fish) than in lower food chain level organisms in bioaccumulation experiments with CeO 2 NPs in the constructing freshwater ecosystem [58].…”

Metabolomic and bioenergetic responses of human hepatocellular carcinoma cells following exposure to commercial copper hydroxide nanopesticide

“…Trophic transfer has been reported for several nanoparticles in aquatic and terrestrial food chains. [15][16][17][18][19][20][21][22] Based on the limited studies available, Cu(OH) 2 nanopesticide exposure can adversely affect aquatic organisms, including the estuarine amphipod Leptocheirus plumulosus, 23 embryonic zebrafish (Danio rerio), 24,25 microbial communities, [26][27][28][29] and other non-target organisms. Most significant is that there are no data on the potential for copper nanopesticide-induced toxicity in mammals, especially humans.…”