@article {9333, title = {Aluminium-based galvanic anode impacts the photosynthesis of microphytobenthos and supports the bioaccumulation of metals released.}, journal = {Aquat Toxicol}, volume = {258}, year = {2023}, month = {2023 May}, pages = {106501}, abstract = {

Very few studies have looked at the potential biological effects of degradation products of galvanic anodes particularly on primary producers which are central to food webs in marine ecosystems. The galvanic anode cathodic protection system (GACP) is widely used to protect submerged metallic structures from corrosion. Aluminium (Al) and zinc (Zn) are the main constituents of galvanic anodes and are therefore released in the marine environment by oxidation process to form ions or oxy-hydroxides. The main objective of our study was to evaluate the effects of the metals released from an aluminium-based galvanic anode on microphytobenthos performance in term of biofilm growing through the analysis of photosynthetic parameters, the determination of chlorophyll and extracellular polymeric substances (EPS). The bioaccumulation of Al and Zn were measured in the microphytobenthic compartment collected at the surface of polyvinyl chloride (PVC) plates exposed during 13 days to seawaters enriched in different concentrations of metals released from dissolution of one anode. Determination of bioconcentration factors confirmed that the microphytobenthos has incorporated Al. A significative effect was observed on the Chl a concentration for the higher tested concentration ([Al]\ =\ 210.1\ {\textpm}\ 60.2\ {\textmu}g L\ \ ; [Zn]\ =\ 20.2\ {\textpm}\ 1.4\ {\textmu}g L\ \ ). The seawater exposed to the anode affected the MPB productivity (ETRII) with consequences on acclimatation light (Ek), absorption cross section of PSII (σ), F/F and NPQ. Regarding the EPS production, the anode degradation presented an impact on high and low molecular weight of both carbohydrates and protein fractions of microphytobenthos suggesting that EPS play an essential role in sequestering metal contaminants to maintain the integrity of the biological membranes and the functionality of the cellular organelles. The accumulation of Al released by GACP in microphytobenthos cells could lead to physiologic problems in photosynthetic organisms.

}, keywords = {Aluminum, Bioaccumulation, Ecosystem, Electrodes, Photosynthesis, Water Pollutants, Chemical, Zinc}, issn = {1879-1514}, doi = {10.1016/j.aquatox.2023.106501}, author = {Levallois, Alexandre and Vivier, Baptiste and Caplat, Christelle and Goux, Didier and Orvain, Francis and Lebel, Jean-Marc and Claquin, Pascal and Chasselin, L{\'e}o and Basuyaux, Olivier and Serpentini, Antoine} } @article {6709, title = {Transfer of elements released by aluminum galvanic anodes in a marine sedimentary compartment after long-term monitoring in harbor and laboratory environments}, journal = {Chemosphere}, volume = {239}, year = {2020}, pages = {124720}, abstract = {Cathodic protection by galvanic anodes (GACP) is often used to protect immerged metallic structures in harbor environments, especially GACP employing aluminum-based anodes. To follow a previous study that was performed in a laboratory on Al-anode, two monitoring periods were performed in parallel, one in an in situ environment (in the Port of Calais) for 42 months and the other in a laboratory for 18 months, to evaluate the transfer of metals constituting the Al-anode towards the sedimentary compartment. During each monitoring, two conditions of agitation of water (weak and strong) were compared, and different factors of sediment quality were used to assess the enrichment and potential toxic effects of these released metals. The results showed that the dissolution of Al-anode-induced a greater Zn enrichment of sediment than an Al enrichment. This is in contrast with the abundance of these elements present in the composition of the anode and suggested a potential toxic effect for marine organisms with regards to the discovered Zn level, especially in confined areas.}, keywords = {Aluminum, galvanic anode, Harbor, Marine sediments, Quality index, Zinc}, issn = {0045-6535}, doi = {10.1016/j.chemosphere.2019.124720}, url = {http://www.sciencedirect.com/science/article/pii/S0045653519319502}, author = {Christelle Caplat and Olivier Basuyaux and Pineau, S and Deborde, Jonathan and Grolleau, AM and S. Leglatin and Mahaut, Marie-Laure} } @article {4047, title = {Impact of Galvanic Anode Dissolution onMetal Trace Element Concentrations in Marine Waters}, journal = {water, air \& soil pollution}, volume = {226}, year = {2015}, month = {11/2015}, pages = {226-423}, abstract = {

Submerged harbor steel structures often employ cathodic protection using galvanic anodes to guard against corrosion. A laboratory experiment, with three different cathodic protection configurations by galvanic aluminum-based anodes, was performed to evaluate the potential metal transfer from the anodic alloy dissolution into the surrounding marine water. The anode dissolution rate is proportional to the imposed current demands and induced a significant Al, In, and Zn transfer in the dissolved and particulate fractions of the corrosion product layers covering the anode surface. These layers were poorly adherent, even under low hydrodynamic conditions. Consequently, at the anode vicinity, the suspended particle matter and dissolved fraction of surrounding marine waters showed strong enrichments in Al and Zn, respectively, the values of which could potentially affect the adjacent biota. After the anode activation period, however, the metal inputs from galvanic anode dissolution are rapidly diluted by seawater renewal. At regional scale, these metal fluxes should be negligible compared to river and wastewater fluxes. These results also showed that it is difficult to assess the impact of the anode dissolution on the concentrations of metals in the natural environment, especially for metals included in trace amounts in the anode alloy (i.e., Cu, Fe, In, Mn, and Si) in the aquatic compartment.

}, keywords = {aluminium, galvanic anode, metal transfer, Seawater, Zinc}, issn = {0049-6979}, author = {Deborde, J and Refait, P and Paco Bustamante and Christelle Caplat and Basuyaux, O and Grolleau, AM and M-L Mahaut} }