The contribution of Mytilus sp. in radionuclide transfer between water column and sediments in the estuarine and delta systems of the Rhône river

Distribution of tritium in estuarine waters: the role of organic matter

“…The mean and standard deviation of four replicate experimental values is given (10 and 100 mg L À1 only); nd ¼ not determined. Association of tritium with sediment organic matter was corroborated in our studies by its near-complete (>95%) digestion in untreated estuarine particles by base (1 M NaOH; Table 4), and incomplete (<70%) recovery by acid (1 M HCl), and has been demonstrated in independent studies by its release from contaminated sediment by combustion at >400 C (Gontier et al, 1992;McCubbin et al, 2001). Further evidence of tritium's affinity for organic matter include its extraction from particles by a digestive enzyme (Table 4), apparent salting out of aqueous species (Fig.…”

“…In the vicinity of a nuclear reprocessing plant discharging into the Irish Sea, corresponding measurements indicate K D s of around unit value (BNFL, 2003); in the vicinity of a reprocessing plant in the southern English Channel, the ratio of organically-bound tritium to free-water tritium in biota exceeds unity (Masson et al, 2005). Down-estuary of nuclear installations in the River Rhô ne, France, Gontier et al (1992) report tritium enrichments in sediment (over ambient water) of between 10 and 100, and note that the precise effect appears to be related to the organic content of sediment and the reciprocal of grain size. More recent measurements in the Rhô ne indicate elevated concentrations persisting in sediments upstream of the nuclear establishments (Jean-Baptiste et al, 2007).…”

“…Such enrichment, including concentration factors in excess of 10 5 for demersal fish and shellfish, were ascribed to the existence of organically-bound tritium (OBT) in local nuclear waste in the form of specific biochemicals, including carbohydrates, vitamins and amino acids (McCubbin et al, 2001). More generally, however, significant interaction of tritium with particles and organisms has been observed when tritium is released to the environment as tritiated water, HTO (Gontier et al, 1992;Masson et al, 2005;RIFE, 2007;Jean-Baptiste et al, 2007). For example, the activity of tritium in radioactive waste has been found to decrease 3-or 4-fold during water infiltration through sediments, an effect attributed to isotopic exchange between clay minerals and HTO and to adsorption of tritium to H-free minerals (Ló pez-Galindo et al, 2008).…”

Le tritium organique dans les écosystèmes d’eau douce : évolution à long terme dans l’environnement des centres nucléaires de production d’électricité français

“…Ces industries étaient largement implantées dans le Jura français et en Suisse il y une vingtaine d'années et le demeurent encore aujourd'hui en Suisse. Gontier et al (1992) et Pally et al (1993) avaient déjà souligné cette zone singulière vraisemblablement soumise aux rejets de l'industrie horlogère. Jean-Baptiste et al (2007) ont montré plus récemment que ces apports persistaient sans que l'on puisse en déterminer la composition exacte (matière organique naturelle marquée par les rejets des installations de fabrication de composés tritiés, ou rejet de composés tritiés tels que le polystyrène).…”

Human health risk assessment of environmental and dietary exposure to natural radionuclides in the Catalan stretch of the Ebro River, Spain

“…Some data on radioactivity levels in food from the literature are shown in Table 3: Relatively enhanced concentrations of 210 Pb and 210 Po had been already detected in fish and seafood, and more specifically in mussels, from Brazil and the Aegean Sea (Cunha et al 2001;Ugur et al 2002). Mussels are typically characterized as filterfeeding organisms, with a high capacity of particle retention (Gontier et al 1992). On the other hand, the concentrations in rice would fit with those found by Santos et al (2002) in Rio de Janeiro, Brazil (0.01-0.16 Bq kg −1 fresh weight).…”