Nanostructured cellulose sponge engineered for marine environmental remediation: Eco-safety assessment of its leachate on sea urchin reproduction (Part A)

Nanostructured cellulose sponges (CNS) have been developed as eco-friendly and sustainable engineered materials for marine environmental remediation. Despite their functionality, sensitivity, efficiency and specificity have been proved, CNS application is still limited since their environmental safety (eco-safety) has not been completely assessed. In this study, CNS were allowed to leach in natural seawater simulating the remediation process condition and the eco-safety of CNS leachate on sea urchin reproduction has been assessed by carrying out a multi-response integrated approach, combining standardized ecotoxicity tests, innovative bioassays and gamete quality assessment. Overall, the ecotoxicity data indicate that CNS leachate affects gamete quality, gamete fertilisation competence, and embryo development probably associated with the release of chemical additives used during the synthesis process. However, in the framework of the eco-design approach, consecutive leaching treatments and conditioning of CNS in seawater open the route for a new safety protocol successfully solving the ecotoxicity while maintaining CNS sorbent properties. A safe environmental application of the resulting conditioned CNS for seawater pollution remediation is envisaged.

Application of different enzyme assays and biomarkers for pollution monitoring of the marine environment

New phosphatase and DNase inhibition tests for assessing the total pollution of a natural marine ecosystem were applied. The seawater samples with different pollution degrees were collected in the Troitsa Bay of the Peter the Great Bay (the Sea of Japan). The sensitivity of the alkaline phosphatase test to integrated pollution was in accordance with the sensitivity of the standard sea urchin sperm cell toxicity test. The increased seawater pollution level was shown to result in an up to fourfold increase in specific activities of acid and alkaline phosphatases from the mussel Crenomytilus grayanus. It was demonstrated that a complex methodological approach can be used to assess marine water areas, as well as to assess the biological conditions of invertebrates adapting to different environmental and anthropogenic effects.