Bioaccumulation; Mercury; Methylmercury; Phytoplankton; Chlamydomonas reinhardtii; Dissolved organic matter; Ecotoxicology; Environmental Chemistry; Water quality
Li Mengting, Slaveykova Vera I. (2022), Dual role of titanium dioxide nanoparticles in the accumulation of inorganic and methyl mercury by crustacean Daphnia magna through waterborne and dietary exposure, in
Environmental Pollution, 295, 118619-118619.
Li Mengting, Liu Wei, Slaveykova Vera I. (2020), NanoTiO2 materials mitigate mercury uptake and effects on green alga Chlamydomonas reinhardtii in mixture exposure, in
Aquatic Toxicology, 224, 105502-105502.
Li Mengting, Slaveykova Vera I. (2020), A density gradient centrifugation method for rapid separation of nanoTiO2 and TiO2 aggregates from microalgal cells in complex mixtures with mercury, in
MethodsX, 7, 101057-101057.
Worms Isabelle A. M., Chmiel Hannah E., Traber Jacqueline, Tofield-Pasche Natacha, Slaveykova Vera I. (2019), Dissolved Organic Matter and Associated Trace Metal Dynamics from River to Lake, Under Ice-Covered and Ice-Free Conditions, in
Environmental Science & Technology, 53(24), 14134-14143.
Mercury is a toxic contaminant of global importance. Hg concentrations in the water column are very low, however both inorganic mercury (IHg) and methylmercury (MeHg) significantly concentrate in aquatic biota. In addition, a MeHg strongly biomagnifies in the food chain, thus representing an important threat for ecosystems and humans e.g. through fish consumption. However, Hg contents in biota at the top of the food chain, such as fish, seems to be determined by the amount of bioavailable mercury at the base of the food chain. In such as context the present project aims to improve the basic knowledge on different processes governing Hg species bioavailability to phytoplankton and to elucidate the modifying role of water quality variables, with emphasis on dissolved organic matter (DOM). The IHg and MeHg bioavailability dynamics will be characterized by measurement of the cellular mercury contents, uptake fluxes, and cellular responses (e.g. photosynthesis and expression level of the selected genes as candidates for early biomarkers) in a large mercury concentration range. The influence of DOM of different origin such as fulvic and humic-like substances, as well as extracellular polymeric substances on the mercury bioavailability and cellular response will be studied. In parallel IHg and MeHg speciation in the exposure medium will be modeled. As an ubiquitous bioaccumulative and toxic substance, Hg is listed in the priority hazardous substances of the European Union setting Environmental Quality Standards (EQS). Therefore, further ecologically meaningful investigation of Hg bioavailability and understanding the basic processes determining the incorporation of Hg at the base of the food chain seems critical for elaboration of the scientifically sound EQC for mercury. The present research will also contribute to the development of early warning biomarkers in support to biomonitoring efforts of mercury monitoring and support the implementation of the Minamata Convention.