Suitability of a Cellulose-Based Nanomaterial for the Remediation of Heavy Metal Contaminated Freshwaters: A Case-Study Showing the Recovery of Cadmium Induced DNA Integrity Loss, Cell Proliferation Increase, Nuclear Morphology and Chromosomal Alterations on Dreissena polymorpha

Abstract

The contamination of freshwaters by heavy metals represents a great problem, posing a threat for human and environmental health. Cadmium is classified as carcinogen to humans and its mechanism of carcinogenicity includes genotoxic events. In this study a recently developed eco-friendly cellulose-based nanosponge (CNS) was investigated as a candidate in freshwater nano-remediation process. For this purpose, CdCl2 (0.05 mg L−1) contaminated artificial freshwater (AFW) was treated with CNS (1.25 g L−1 for 2 h), and cellular responses were analyzed before and after CNS treatment in Dreissena polymorpha hemocytes. A control group (AFW) and a negative control group (CNS in AFW) were also tested. DNA primary damage was evaluated by Comet assay while chromosomal damage and cell proliferation were assessed by Cytome assay. AFW exposed to CNS did not cause any genotoxic effect in zebra mussel hemocytes. Moreover, DNA damage and cell proliferation induced by Cd(II) turned down to control level after 2 days when CNS were used. A reduction of Cd(II)-induced micronuclei and nuclear abnormalities was also observed. CNS was thus found to be a safe and effective candidate in cadmium remediation process being efficient in metal sequestering, restoring cellular damage exerted by Cd(II) exposure, without altering cellular physiological activity.

Synthesis and Application of Cellulose-Polyethyleneimine Composites and Nanocomposites: A Concise Review

“…Moreover, the new composite has been further tested for its remediation action in realistic media, both in fresh water mono-contaminated with Cd(II) [72] and in sea-water mono-contaminated with Zn(II) [69]. In both cases, once again, the remediation approach was validated by in vivo tests.…”

Cellular Responses Induced by Zinc in Zebra Mussel Haemocytes. Loss of DNA Integrity as a Cellular Mechanism to Evaluate the Suitability of Nanocellulose-Based Materials in Nanoremediation

“…and in other aquatic organisms [19,42]. Baseline levels of DNA damage in zebra mussel haemocytes were also found to correlate with animal maintenance temperature [43].…”

“…Recently, sustainable cellulose-based nanomaterials are becoming increasingly attractive for their potential use in environmental remediation [ 14 , 15 , 16 , 17 , 18 , 19 ]. In this background, ecotoxicology can provide suitable tools able to select eco-safe and sustainable nanomaterials for environmental remediation [ 20 ].…”

The Era of Nanomaterials: A Safe Solution or a Risk for Marine Environmental Pollution?

“…The resulting CNS evidences a nanoporous structure characterized by a high chemical and mechanical stability [ 86 ]. CNS, used as it is or ground into powder, have demonstrated high efficiency to remove heavy metals (Zn, Cd, Cr, Hg, Ni, Cu) and organic dyes from water and artificial seawater [ 45 , 85 , 89 , 157 , 158 ]. More importantly, these nanostructured materials have been synthesized and optimized following the lab scale, the eco-design concept previously discussed, in order to ensure the eco-safety of the nanosponge, while preserving its remediation efficiency ( Figure 5 ).…”