Specific Pathways of Dietary Methylmercury and Inorganic Mercury Determined by Mercury Speciation and Isotopic Composition in Zebrafish (Danio rerio)
Language
EN
Article de revue
This item was published in
Environmental Science and Technology. 2015-09-23, vol. 49, n° 21, p. 12984-12993
English Abstract
An original approach is proposed to investigate inorganic (iHg) and methylmercury (MeHg) trophic transfer and fate in a model fish, Danio rerio , by combining natural isotopic fractionation and speciation. Animals were ...Read more >
An original approach is proposed to investigate inorganic (iHg) and methylmercury (MeHg) trophic transfer and fate in a model fish, Danio rerio , by combining natural isotopic fractionation and speciation. Animals were exposed to three different dietary conditions: i. 50 ng Hg g-1, 80% as MeHg; ii. diet enriched in MeHg 10000 ng Hg g-1, 95% as MeHg and iii. diet enriched in iHg 10000 ng Hg g-1, 99% as iHg. Harvested was carried out after 0, 7, 25 and 62 days. Time-dependent Hg species distribution and isotopic fractionation in fish organs (muscle, brain, liver) and faeces, exhibited different patterns, as a consequence of their dissimilar metabolization. The rapid isotopic re-equilibration to the new MeHg-food source reflects its high bioaccumulation rate. Relevant aspects related to Hg excretion are also described. This study confirms Hg isotopic fractionation as a powerful tool to investigate biological processes, although its deconvolution and fully understanding is still a challenge.Read less <