Lithium isotopes in marine food webs: Effect of ecological and environmental parameters

Non-conventional stable isotopes have received increasing attention in the past decade to investigate multi-level ecological connections from individuals ecosystems. More recently, trace and non-nutrient elements, potentially toxic (i.e., Hg), also been recognized of great significance discriminate sources, transports, bioaccumulation, as well trophic transfers. In contrast, lithium (Li) concentrations its isotope compositions (δ 7 Li) remain poorly documented aquatic ecosystems, despite possible accumulation marine organisms, industrial production, demonstrated hazardous effects on biota. Here, we present first Li investigation various soft tissues, organs or whole plankton, bivalves, cephalopods, crustaceans, fish different biogeographical regions [North Mediterranean Sea, North Atlantic Ocean (Bay Biscay), South East Pacific (New Caledonia), Southern Indian (Kerguelen Islands)]. Independently considered δ values range widely, 4.6‰ (digestive gland bivalves) 32.0‰ (zooplankton). Compared homogeneous seawater ∼ 31.2‰ ± .3‰), organisms mostly fractionate favor light ( 6 Li). Within same taxonomic group, significant differences are observed among organs, indicating a key role physiology distribution isotopes. Statistically, position is only slightly related average composition tissues but this aspect deserves further at organ level. Other potential influences uptake by ingestion gill ventilation. Overall, work constitutes extensive baseline coastal large geographic areas preserved anthropogenic contamination.