I am interested in the role that marine organisms play in the cycle of chemicals that are of relevance for the health of ecosystem and human, as well as these human and ecosystem health consequences. My research generates new knowledge on metal bioavailability of their bioaccumulation patterns in marine systems, and this knowledge can be used in environmental risk assessments as well as other applications (let me know if you have any more ideas and suggestions). Note that risk assessment approach has frequently relied on the levels of dissolved contaminants, ignoring potentially relevant chemical (e.g. chemical speciation) and biological processes (e.g. dietary assimilation of metals). Many elements (mercury – Hg, arsenic – As, cadmium – Cd etc.) naturally present in the environment can become enriched and elevated beyond the natural background due to anthropogenic activities (e.g. agriculture, industry including energy production). Those elements enter aquatic – both pelagic and benthic – food chains in the oceans. Organisms can incorporate elements into their body via aqueous exposure and/or by ingestion.
In the past, I have examined mechanisms that could influence biogeochemical transformations and bioavailability of arsenic, cadmium and chromium to deposit-feeding polychaetes (Ph.D. dissertation work), an essential step towards understanding the bioaccumulation. Later on (post-doc) I have studied bioaccumulation of radioactive isotopes of cesium (i.e. 137Cs and 134Cs) that were released by the Dai-ichi nuclear facility near Fukushima. Colleagues and I have used the Fukushima-cesium as a tracer of cross-Pacific migration of the Pacific bluefin tuna. Upon departure at UConn at Avery Point, where I am associated with the lab of professor Robert Mason, I have shifted my focus to flow of Hg in marine food webs. Knowledge of this topic is of critical importance as the organic form of Hg i.e. methylmercury is a significant neurotoxicant in human and its main source for us is marine fish consumption.
Baumann Z. and N.S. Fisher. 2011. Relating the sediment phase speciation of As, Cd and Cr with their bioavailability for the deposit-feeding polychaete Nereis succinea. Environmental Toxicology and Chemistry 30: 747-756
Baumann Z. and N.S. Fisher. 2011. Modeling metal bioaccumulation in a deposit-feeding polychaete from labile sediment fractions and from pore water. Science of the Total Environment 409: 2607-2615
Buesseler, K. O., S. R. Jayne, N. S. Fisher, I. I. Rypina, H. Baumann, Z. Baumann, C. F. Breier, E. M. Douglass, J. George, A. M. Macdonald, H. Miyamoto, J. Nishikawa, S. M. Pike, and S. Yoshida. 2012. Fukushima-derived radionuclides in the ocean and biota off Japan. Proceedings of the National Academy of Sciences of the United States of America. 109: 5984-5988
Baumann Z., Koller. A. and N.S. Fisher. 2012. Factors influencing the assimilation of arsenic in a deposit-feeding polychaete. Comparative Biochemistry and Physiology Part C: Toxicology and Pharmacology 156: 42-50
Madigan, D.J., Baumann Z., and Fisher N.S. 2012. Pacific bluefin tuna (Thunnus orientalis) transport Fukushima-derived radionuclides from Japan to California. Proceedings of the National Academy of Sciences of the United States of America. 109: 9483-9486
Madigan, D.J., Baumann Z., Snodgrass, O.E., Ergül, H.E., Dewar, H., and Fisher, N.S. (2013) Radiocesium in Pacific bluefin tuna Thunnus orientalis in 2012 validates new tracer technique. Environmental Science and Technology 47: 2287-2294
Fisher, N.S., Beaugelin-Seiller K., Hinton, T.G., Baumann, Z., Madigan, D.J., Garnier-Laplace, J. (2013) An evaluation of radiation doses and associated risk from the Fukushima nuclear accident to marine biota and human consumers of seafood. Proceedings of the National Academy of Sciences of the United States of America 110: 10670-10675
Baumann, Z., Casacuberta, N., Baumann, H., Masque, P., and Fisher N.S. (2013) Natural and Fukushima-derived radioactivity in macroalgae and mussels along the Japanese shoreline. Biogeoscience 10: 2617-2633
Fisher, N.S., and Z. Baumann (2013) Application of radiotracer methodology for understanding the influence of geochemical fractionation on metal bioavailability in estuarine sediments. In: Proceedings of “IAEA International Symposium on Isotopes in Hydrology, Marine Ecosystems, and Climate Change Studies”
Madigan, D.J. Baumann Z., Carlisle A.B., Hoen, D.K, Popp, B.N., Dewar, H., Snodgrass, O.E., Block, B.A., and Fisher, N.S., (2013) Reconstructing trans-oceanic migration patterns of Pacific bluefin tuna using a chemical tracer toolbox. Ecology 95: 1674-1683
Nalluri D., Baumann Z., Abercrombie D.L., Chapman D.L., Hammerschmidt C.R., Fisher N.S. (2014) Methylmercury in dried shark fins and shark fin soup from American restaurants. Science of the Total Environment 496: 644-648
Madigan D.J., Baumann Z., Carlisle A.B., Hoen D.K, Popp B.N., Dewar H., Snodgrass O.E., Block B.A., and Fisher S. (2014) Reconstructing transoceanic migration patterns of Pacific bluefin tuna using a chemical tracer toolbox. Ecology 95: 1674-1683.
Baumann, H., Wells, R.J.D., Rooker, J.R., Zhang, S., Baumann, Z., Madigan, D.J., Dewar, H., Snodgrass, O.E., Fisher, N.S., (2015) Combining otolith microstructure and trace elemental analyses to infer the arrival of juvenile Pacific bluefin tuna in the California current ecosystem. ICES Journal of Marine Science: Journal du Conseil. 72: 2128-2138.
Baumann Z. Fisher N.S., Gobler C.J., Buesseler K.O., George J.A., Pike S.M., Breier C.F., Nishikawa J. (2015) Fukushima 137Cs in planktonic food webs off Japan. Deep Sea Research Part I: Oceanographic Research Papers. 106: 9-16.