title: Bioaccessibility of selenium after human ingestion in relation to its chemical species and compartmentalization in maize.
abstract: Selenium is a micronutrient needed by all living organisms including humans, but often present in low concentration in food with possible deficiency. From another side, at higher concentrations in soils as observed in seleniferous regions of the world, and in function of its chemical species, Se can also induce (eco)toxicity. Root Se uptake was therefore studied in function of its initial form for maize (Zea mays L.), a plant widely cultivated for human and animal food over the world. Se phytotoxicity and compartmentalization were studied in different aerial plant tissues. For the first time, Se oral human bioaccessibility after ingestion was assessed for the main Se species (Se(IV) and Se(VI)) with the BARGE ex vivo test in maize seeds (consumed by humans), and in stems and leaves consumed by animals. Corn seedlings were cultivated in hydroponic conditions supplemented with 1 mg L(-1) of selenium (Se(IV), Se(VI), Control) for 4 months. Biomass, Se concentration, and bioaccessibility were measured on harvested plants. A reduction in plant biomass was observed under Se treatments compared to control, suggesting its phytotoxicity. This plant biomass reduction was higher for selenite species than selenate, and seed was the main affected compartment compared to control. Selenium compartmentalization study showed that for selenate species, a preferential accumulation was observed in leaves, whereas selenite translocation was very limited toward maize aerial parts, except in the seeds where selenite concentrations are generally high. Selenium oral bioaccessibility after ingestion fluctuated from 49 to 89 % according to the considered plant tissue and Se species. Whatever the tissue, selenate appeared as the most human bioaccessible form. A potential Se toxicity was highlighted for people living in seleniferous regions, this risk being enhanced by the high Se bioaccessibility.
authors.affiliation: EcoLab (Laboratoire Ecologie Fonctionnelle et Environnement), INP, UPS, ENSAT, Université de Toulouse, Avenue de l'Agrobiopole, 31326, Castanet-Tolosan, France.|EcoLab, CNRS, 31326, Castanet-Tolosan, France.
authors.forename: Stéphane
authors.initials: S
authors.lastname: Mombo
authors.affiliation: Géosciences Environnement Toulouse (GET), Observatoire Midi Pyrénées, CNRS, IRD, Université de Toulouse, 14 Avenue E. Belin, 31400, Toulouse, France.
authors.forename: Eva
authors.initials: E
authors.lastname: Schreck
authors.affiliation: CERTOP, UMR5044, Université Toulouse Jean Jaurès, Maison de la Recherche, 5 allée Antonio Machado, 31058, Toulouse Cedex 9, France. camille.dumat@ensat.fr.|INP-ENSAT, Av. Agrobiopôle, BP 32607, 31326, Castanet-Tolosan, France. camille.dumat@ensat.fr.
authors.forename: Camille
authors.initials: C
authors.lastname: Dumat
authors.affiliation: EcoLab (Laboratoire Ecologie Fonctionnelle et Environnement), INP, UPS, ENSAT, Université de Toulouse, Avenue de l'Agrobiopole, 31326, Castanet-Tolosan, France.|EcoLab, CNRS, 31326, Castanet-Tolosan, France.
authors.forename: Christophe
authors.initials: C
authors.lastname: Laplanche
authors.affiliation: EcoLab (Laboratoire Ecologie Fonctionnelle et Environnement), INP, UPS, ENSAT, Université de Toulouse, Avenue de l'Agrobiopole, 31326, Castanet-Tolosan, France.|EcoLab, CNRS, 31326, Castanet-Tolosan, France.
authors.forename: Antoine
authors.initials: A
authors.lastname: Pierart
authors.affiliation: UPMC, UFR 918 - GESE, Sorbonne Universités, 75005, Paris Cedex 05, France.
authors.forename: Mélanie
authors.initials: M
authors.lastname: Longchamp
authors.affiliation: Géosciences Environnement Toulouse (GET), Observatoire Midi Pyrénées, CNRS, IRD, Université de Toulouse, 14 Avenue E. Belin, 31400, Toulouse, France.
authors.forename: Philippe
authors.initials: P
authors.lastname: Besson
authors.affiliation: UPMC, CNRS, EPHE, UMR 7619 Metis, Sorbonne Universités, 4 Place Jussieu, 75005, Paris, France.
authors.forename: Maryse
authors.initials: M
authors.lastname: Castrec-Rouelle
mesh_terms: D000818:Animals; D001682:Biological Availability; D005506:Food Contamination; D006801:Humans; D035261:Plant Components, Aerial / Q000737:chemistry; D018517:Plant Roots / Q000737:chemistry; D012639:Seeds / Q000737:chemistry; D012643:Selenium / Q000737:chemistry / Q000378:metabolism* / Q000633:toxicity*; D003313:Zea mays / Q000254:growth & development / Q000378:metabolism*
chemical_list: D012643:Selenium
keywords: Chemical species; Compartmentalization; Health risks; Maize (Zea mays L.); Oral bioaccessibility; Se