Inorganic arsenic in holopelagic Sargassum spp. stranded in the Mexican Caribbean: Seasonal variations and comparison with international regulations and guidelines

• Published in: Aquatic botany 2023-09, Vol.188, p.103674, Article 103674
• Main Authors: Ortega-Flores, Paulina Annette, Gobert, Tristan, Méndez-Rodríguez, Lía Celina, Serviere-Zaragoza, Elisa, Connan, Solène, Robledo, Daniel, Freile-Pelegrín, Yolanda, Anda Montañez, Juan Antonio de, Waeles, Matthieu
• Format: Article
• Language: English
• Subjects: Chemical Sciences; Holopelagic Sargassum; Inorganic arsenic; Regulations; Valorisation
• ISSN: 0304-3770
• DOI: 10.1016/j.aquabot.2023.103674

Due to the massive proliferation and stranding of holopelagic Sargassum spp. over the last decade, different strategies for the sustainable valorisation of Sargassum biomass have been explored and investigated. One limitation to the development of Sargassum biomass valorisation is related to its high arsenic (As) content. The toxicity of As depends on the chemical forms present and their oxidation or valence state, classified as inorganic and organic compounds, with the inorganic As compounds being much more toxic than the organic ones. The aim of the present study was to determine the inorganic arsenic (iAs) content in holopelagic Sargassum spp. for which almost no information on stranded biomass is available. In this study, we examined the iAs content in the three holopelagic Sargassum morphotypes collected over a seasonal cycle in 2018–2019. The iAs concentrations ranged from 12.7 to 62.9 mg kg−1, representing 14.1–81.7% of total arsenic (TotAs). The iAs content was compared between species and seasons and discussed in the context of existing international regulations and guidelines. •Inorganic arsenic (iAs) content was monitored in stranded holopelagic Sargassum from the Mexican Caribbean.•The iAs content ranged from 12.7 to 62.9 mg kg−1 representing between 14.1% and 81.7% of total arsenic (TotAs).•The proportion of iAs increased over the period studied.•The highest iAs content was found in the warm-dry season with an annual mean of 41.0 mg kg−1.•The iAs content is well above the levels allowed by international guidelines.