Reduced transfer of metals and metalloids from stranded Sargassum to adjacent organisms

Since 2011 unprecedented biomass of holopelagic brown macroalgae Sargassum has stranded along the Caribbean coasts, inducing damages for coastal ecosystems, economy and human health. By accumulating metals and metalloids,Sargassum spp. can play a role in contaminant transportation from offshore to the coast. In order to evaluate those potential transfers, organisms (phanerogam: Halophila stipulacea, gastropoda: Littoraria angulifera and bivalvia: Isognomon alatus) from mangroves and seagrass of Guadeloupe (French West Indies) were sampled in coats exposed (Petit Cul-de-Sac Marin) and not exposed (Grand Cul-de-Marin) to Sargassum stranding. Two campaigns were realized during periods of massive (July 2020) and reduced (January 2021) stranding of Sargassum. Studied species presented different compositions in their 28 metal(loid)s trace elements with higher concentration in the bivalves Isognomon alatusin particular for the total Arsenic (tAs). None of the studied species presented an increased MTE concentration according to i) geographical proximity with stranded Sargassum and ii) temporal period of higher Sargassum stranding. The study suggests that transfer of metal, including As, from Sargassum to marine organisms would be limited.

Presentation Preference: Oral

Primary Presenter: Pierre-Yves Pascal, Université des Antilles (pierreyves.pascal@gmail.com)

Authors:

Océanne-Amaya Cipolloni, Université des Antilles  (oceanne.cipolloni@gmail.com)

Magalie Baudrimont, Université de Bordeaux  (magalie.baudrimont@u-bordeaux.fr)

Benoit Simon-Bouhet, Université de La Rochelle  (bsimonbo@univ-lr.fr)

Emilie Dassie, Université de Bordeaux  (emilie.dassie@u-bordeaux.fr)

Pierre-Yves Pascal, Université des Antilles  (pierreyves.pascal@gmail.com)