Fabian Fischer is an Assistant Professor in the Department of Pathology and Laboratory Medicine at Brown University. His lab asks why the same chemical exposure produces very different internal doses and health outcomes across people. The group combines in vitro cell-based bioassays, high-resolution mass spectrometry of biospecimens, and physiologically based pharmacokinetic (PBPK) modeling to quantify the concentrations that actually reach target tissues and drive biological effects of drugs and environmental chemicals.
To advance precision health across environmental chemicals and therapeutics, current projects explore how age, sex, genetics, and health conditions like diabetes or liver disease alter absorption, internal distribution, and clearance. By identifying who is most vulnerable to toxic accumulation or sub-therapeutic drug doses, the lab defines critical windows of susceptibility and translates these insights into targeted exposure interventions, precision dosing, and personalized medicine.
Dr. Fischer received his doctorate in environmental sciences from the University of Tübingen (Germany) in 2018 and was awarded the German Chemical Society prize for best doctoral thesis. He held JSPS and Alexander von Humboldt fellowships at the National Institute for Environmental Studies in Japan and a postdoctoral position at the Harvard John A. Paulson School of Engineering and Applied Sciences. He joined Brown in 2026 as Assistant Professor from the University of Rhode Island College of Pharmacy, where he retains an adjunct appointment. He also holds an Associate appointment at Harvard and an Adjunct appointment at Texas A&M University and serves as an Early Career Editor for Environmental Science & Technology Toxicology.
| Fischer, Fabian C., Geyer, Liam, Rodriguez, Miguel, Henneberger, Luise, Escher, Beate I. "DYNAMEX: A Time-Resolved Model for Predicting Distribution of Chemicals in In Vitro Cell Assays." Environmental Science & Technology, 2026. |
| Agudelo Areiza, Juliana, Becanova, Jitka, Vojta, Simon, Ganglbauer, Johanna, Apte, Udayan, Brunetti, Luigi, Kumer, Sean, Haque, Faiz, Kim, Euna, Sunderland, Elsie M., Lohmann, Rainer, Fischer, Fabian C., Slitt, Angela. "Presence of Legacy and Emerging PFAS in Human Liver Specimens Banked in the United States from 2000 to 2024." Environmental Science & Technology, vol. 60, no. 15, 2026, pp. 11281-11292. |
| Modaresi, Seyed Mohamad Sadegh, Becanova, Jitka, Vojta, Simon, Ryu, Sangwoo, Kaye, Emily M., Agudelo, Juliana, Diolintzi, Anastasia, Skende, Olga, Storch, Judith, Fischer, Fabian C., Slitt, Angela. "Liver and Intestinal Fatty Acid Binding Proteins Are Not Critical for Perfluorooctanesulfonate (PFOS) Tissue Distribution and Elimination in Mice." Chemical Research in Toxicology, vol. 38, no. 9, 2025, pp. 1576-1584. |
| Kaye, Emily M., Becanova, Jitka, Vojta, Simon, Lohmann, Rainer, Fischer, Fabian Christoph, Slitt, Angela. "Toxicokinetics and Perfluorooctanesulfonic Acid-Induced Liver Protein Expression Are Markedly Altered in Mice Lacking Albumin." Chemical Research in Toxicology, vol. 38, no. 7, 2025, pp. 1183-1191. |
| Baumert, Brittney O., Maretti-Mira, Ana C., Walker, Douglas I., Li, Zhenjiang, Stratakis, Nikos, Wang, Hongxu, Zhao, Yinqi, Fischer, Fabian Christoph, Jia, Qiran, Valvi, Damaskini, Bartell, Scott M., Chen, Jiawen Carmen, Inge, Thomas, Ryder, Justin R., Jenkins, Todd, Sisley, Stephanie, Xanthakos, Stavra, Kleiner, David E., Kohli, Rohit, Rock, Sarah, Eckel, Sandrah P., La Merrill, Michele A., Aung, Max M., Salomon, Matthew P., McConnell, Rob, Goodrich, Jesse, Conti, David V., Golden-Mason, Lucy, Chatzi, Lida. "Translational framework linking perfluoroheptanoic acid (PFHpA) exposure to metabolic dysfunction associated steatotic liver disease in adolescents." Communications Medicine, vol. 5, no. 1, 2025. |
| Fischer, Fabian C., Thackray, Colin, Ferguson, Nicholas, Chicoine, Christian, Skende, Olga, Hu, Zhiji, Zhu, Yumin, Slitt, Angela, Sunderland, Elsie M. "Understanding Mechanisms of PFAS Absorption, Distribution, and Elimination Using a Physiologically Based Toxicokinetic Model." Environmental Science & Technology, vol. 59, no. 26, 2025, pp. 13240-13250. |
| Fischer, Fabian Christoph, Ludtke, Sophia, Thackray, Colin, Pickard, Heidi M., Haque, Faiz, Dassuncao, Clifton, Endo, Satoshi, Schaider, Laurel, Sunderland, Elsie M. "Binding of Per- and Polyfluoroalkyl Substances (PFAS) to Serum Proteins: Implications for Toxicokinetics in Humans." Environmental Science & Technology, vol. 58, no. 2, 2024, pp. 1055-1063. |
| Baumert, Brittney O., Eckel, Sandrah P., Goodrich, Jesse A., Li, Zhenjiang, Stratakis, Nikos, Walker, Douglas I., Zhao, Yinqi, Fischer, Fabian Christoph, Bartell, Scott, Valvi, Damaskini, Lin, Xiangping, Fuentes, Zoe Coates, Inge, Thomas, Ryder, Justin, Jenkins, Todd, Kohli, Rohit, Sisley, Stephanie, Xanthakos, Stavra, Rock, Sarah, La Merrill, Michele A., McConnell, Rob, Conti, David V., Chatzi, Lida. "Changes in plasma concentrations of per- and Polyfluoroalkyl substances after bariatric surgery in adolescents from the Teen-Longitudinal Assessment of Bariatric Surgery (Teen-LABS) study." Science of The Total Environment, vol. 930, 2024, pp. 172840. |
| Ryu, Sangwoo, Yamaguchi, Emi, Sadegh Modaresi, Seyed Mohamad, Agudelo, Juliana, Costales, Chester, West, Mark A., Fischer, Fabian, Slitt, Angela L. "Evaluation of 14 PFAS for permeability and organic anion transporter interactions: Implications for renal clearance in humans." Chemosphere, vol. 361, 2024, pp. 142390. |
| Ryu, Sangwoo, Burchett, Woodrow, Zhang, Sam, Modaresi, Seyed Mohamad Sadegh, Agudelo Areiza, Juliana, Kaye, Emily, Fischer, Fabian Christoph, Slitt, Angela L. "Species-Specific Unbound Fraction Differences in Highly Bound PFAS: A Comparative Study across Human, Rat, and Mouse Plasma and Albumin." Toxics, vol. 12, no. 4, 2024, pp. 253. |
| Ryu, Sangwoo, Burchett, Woodrow, Zhang, Sam, Jia, Xuelian, Modaresi, Seyed Mohamad Sadegh, Agudelo Areiza, Juliana, Rodrigues, David, Zhu, Hao, Sunderland, Elsie M., Fischer, Fabian Christoph, Slitt, Angela L. "Unbound Fractions of PFAS in Human and Rodent Tissues: Rat Liver a Suitable Proxy for Evaluating Emerging PFAS?." Environmental Science & Technology, vol. 58, no. 33, 2024, pp. 14641-14650. |
| Hiki, Kyoshiro, Fischer, Fabian Christoph, Nishimori, Takahiro, Endo, Satoshi, Watanabe, Haruna, Yamamoto, Hiroshi. "Influence of water exchange rates on toxicity and bioaccumulation of hydrophobic organic chemicals in sediment toxicity tests." Environmental Science: Processes & Impacts, vol. 25, no. 3, 2023, pp. 609-620. |
| Nielsen, Flemming, Fischer, Fabian C., Leth, Peter M., Grandjean, Philippe. "Occurrence of Major Perfluorinated Alkylate Substances in Human Blood and Target Organs." Environmental Science & Technology, vol. 58, no. 1, 2023, pp. 143-149. |
| Baumert, Brittney O., Fischer, Fabian C., Nielsen, Flemming, Grandjean, Philippe, Bartell, Scott, Stratakis, Nikos, Walker, Douglas I., Valvi, Damaskini, Kohli, Rohit, Inge, Thomas, Ryder, Justin, Jenkins, Todd, Sisley, Stephanie, Xanthakos, Stavra, Rock, Sarah, La Merrill, Michele A., Conti, David, McConnell, Rob, Chatzi, Lida. "Paired Liver:Plasma PFAS Concentration Ratios from Adolescents in the Teen-LABS Study and Derivation of Empirical and Mass Balance Models to Predict and Explain Liver PFAS Accumulation." Environmental Science & Technology, vol. 57, no. 40, 2023, pp. 14817-14826. |
| Nishimori, Takahiro, Hiki, Kyoshiro, Fischer, Fabian Christoph, Endo, Satoshi, Yamamoto, Hiroshi, Watanabe, Haruna. "Comparing 10- and 28-Day Sediment Toxicity and Bioaccumulation of Fluoranthene in Hyalella azteca Using Passive Sampling Techniques." Environmental Toxicology and Chemistry, vol. 41, no. 11, 2022, pp. 2679-2687. |
| Fischer, Fabian C., Hiki, Kyoshiro, Endo, Satoshi. "Free Versus Bound Concentration: Passive Dosing from Polymer Meshes Elucidates Drivers of Toxicity in Aquatic Tests with Benthic Invertebrates." Environmental Toxicology and Chemistry, vol. 43, no. 8, 2022, pp. 1747-1756. |
| Proença, Susana, Escher, Beate I., Fischer, Fabian C., Fisher, Ciarán, Grégoire, Sébastien, Hewitt, Nicky J., Nicol, Beate, Paini, Alicia, Kramer, Nynke I. "Effective exposure of chemicals in in vitro cell systems: A review of chemical distribution models." Toxicology in Vitro, vol. 73, 2021, pp. 105133. |
| Fischer, Fabian Christoph, Hiki, Kyoshiro, Soetaert, Karline, Endo, Satoshi. "Mind the Exposure Gaps—Modeling Chemical Transport in Sediment Toxicity Tests." Environmental Science & Technology, vol. 55, no. 17, 2021, pp. 11885-11893. |
| Hiki, Kyoshiro, Fischer, Fabian Christoph, Nishimori, Takahiro, Watanabe, Haruna, Yamamoto, Hiroshi, Endo, Satoshi. "Spatiotemporal Distribution of Hydrophobic Organic Contaminants in Spiked-Sediment Toxicity Tests: Measuring Total and Freely Dissolved Concentrations in Porewater and Overlying Water." Environmental Toxicology and Chemistry, vol. 40, no. 11, 2021, pp. 3148-3158. |
| Scholz, Stefan, Nichols, John W., Escher, Beate I., Ankley, Gerald T., Altenburger, Rolf, Blackwell, Brett, Brack, Werner, Burkhard, Lawrence, Collette, Timothy W., Doering, Jon A., Ekman, Drew, Fay, Kellie, Fischer, Fabian, Hackermüller, Jörg, Hoffman, Joel C., Lai, Chih, Leuthold, David, Martinovic-Weigelt, Dalma, Reemtsma, Thorsten, Pollesch, Nathan, Schroeder, Anthony, Schüürmann, Gerrit, von Bergen, Martin. "The Eco-Exposome Concept: Supporting an Integrated Assessment of Mixtures of Environmental Chemicals." Environmental Toxicology and Chemistry, vol. 41, no. 1, 2021, pp. 30-45. |
| Fischer, Fabian C., Abele, Cedric, Henneberger, Luise, Klüver, Nils, König, Maria, Mühlenbrink, Marie, Schlichting, Rita, Escher, Beate I. "Cellular Metabolism in High-Throughput In Vitro Reporter Gene Assays and Implications for the Quantitative In Vitro–In Vivo Extrapolation." Chemical Research in Toxicology, vol. 33, no. 7, 2020, pp. 1770-1779. |
| Escher, Beate I., Henneberger, Luise, König, Maria, Schlichting, Rita, Fischer, Fabian C. "Cytotoxicity Burst? Differentiating Specific from Nonspecific Effects in Tox21 in Vitro Reporter Gene Assays." Environmental Health Perspectives, vol. 128, no. 7, 2020. |
| Fischer, Fabian C., Henneberger, Luise, Schlichting, Rita, Escher, Beate I. "How To Improve the Dosing of Chemicals in High-Throughput in Vitro Mammalian Cell Assays." Chemical Research in Toxicology, vol. 32, no. 8, 2019, pp. 1462-1468. |
| Henneberger, Luise, Mühlenbrink, Marie, König, Maria, Schlichting, Rita, Fischer, Fabian C., Escher, Beate I. "Quantification of freely dissolved effect concentrations in in vitro cell-based bioassays." Archives of Toxicology, vol. 93, no. 8, 2019, pp. 2295-2305. |
| Fischer, Fabian C., Cirpka, Olaf A., Goss, Kai-Uwe, Henneberger, Luise, Escher, Beate I. "Application of Experimental Polystyrene Partition Constants and Diffusion Coefficients to Predict the Sorption of Neutral Organic Chemicals to Multiwell Plates in in Vivo and in Vitro Bioassays." Environmental Science & Technology, vol. 52, no. 22, 2018, pp. 13511-13522. |
| Henneberger, Luise, Mühlenbrink, Marie, Fischer, Fabian C., Escher, Beate I. "C18-Coated Solid-Phase Microextraction Fibers for the Quantification of Partitioning of Organic Acids to Proteins, Lipids, and Cells." Chemical Research in Toxicology, vol. 32, no. 1, 2018, pp. 168-178. |
| Fischer, Fabian C., Abele, Cedric, Droge, Steven T. J., Henneberger, Luise, König, Maria, Schlichting, Rita, Scholz, Stefan, Escher, Beate I. "Cellular Uptake Kinetics of Neutral and Charged Chemicals inin VitroAssays Measured by Fluorescence Microscopy." Chemical Research in Toxicology, vol. 31, no. 8, 2018, pp. 646-657. |
| Fischer, Fabian C., Henneberger, Luise, König, Maria, Bittermann, Kai, Linden, Lukas, Goss, Kai-Uwe, Escher, Beate I. "Modeling Exposure in the Tox21 in Vitro Bioassays." Chemical Research in Toxicology, vol. 30, no. 5, 2017, pp. 1197-1208. |
| Fischer, Fabian, Böhm, Leonard, Höss, Sebastian, Möhlenkamp, Christel, Claus, Evelyn, Düring, Rolf-Alexander, Schäfer, Sabine. "Passive Dosing in Chronic Toxicity Tests with the Nematode Caenorhabditis elegans." Environmental Science & Technology, vol. 50, no. 17, 2016, pp. 9708-9716. |
Dr. Fischer’s lab decodes how pharmaceuticals, environmental contaminants, and advanced biological therapies move into, through, and out of the body. To predict how much of a substance reaches a biological site where it can act, the group combines reporter gene cell assays, Transwell cell assays, microextraction binding assays, and quantitative mass spectrometry with physiologically based pharmacokinetic modeling. These approaches quantify cellular responses, tissue binding, crossing of biological barriers (e.g., blood-brain barrier), distribution among organs, and clearance. The developed models connect an environmental exposure or administered dose to concentrations at target sites, and their predictions are tested against measurements from animal studies and human samples. This framework spans environmental contaminants and therapeutic agents, from small molecules to peptides, antibodies, and targeted drug carriers, while accounting for the distinct pharmacokinetic mechanisms that govern each.
The relationship between external and internal dose also differs among people. Age, sex, pregnancy, genetic variation, and liver or kidney disease can alter protein binding, transport, distribution, and clearance. By quantifying these differences, the lab determines when the same external exposure or administered dose may produce higher or lower concentrations at a target site. This work helps identify populations and life stages with distinct internal exposures, inform more precise drug dosing and delivery, and evaluate potential strategies for reducing body burdens of chemical contaminants. Environmental chemicals and drugs are usually studied separately in different fields, but Dr. Fischer’s lab connects them through the same questions: Where does it go? How much reaches the target site? How long does it stay? And how can we adjust that course to optimize dosing, identify risk factors, and improve public health?
2026
2025
2024
Earlier
| Year | Degree | Institution |
|---|---|---|
| 2018 | PhD | Eberhard Karls University of Tübingen |
| 2015 | MSc | Justus Liebig University Giessen |
| 2012 | BSc | University of Bielefeld |
| Postdoctoral Researcher | Harvard University | 2022-2023 | Cambridge, MA, USA |
| Japan Society for the Promotion of Science (JSPS) and Alexander von Humboldt Postdoctoral Fellow | National Institute for Environmental Studies | 2019-2022 | Tsukuba, Ibaraki, Japan |
| Name | Title |
|---|---|
| Bartnikas, Thomas | Associate Professor of Pathology and Laboratory Medicine, Director of the MD/PhD Program |
| Braun, Joseph | Professor of Epidemiology, Director of the Center for Climate, Environment & Health |
| Friedman, Jennifer | Professor of Epidemiology, Professor of Pediatrics |
| Kurtis, Jonathan | Stanley M. Aronson Professor of Pathology and Laboratory Medicine, Chair of Pathology and Laboratory Medicine, Executive Director of the MD-PhD Program |
| Lawler, Sean | Professor of Pathology and Laboratory Medicine |
| Mathiowitz, Edith | Professor of Pathology and Laboratory Medicine, Professor of Engineering |
| Pennell, Kurt | 250th Anniversary Professor of Engineering |
| Plavicki, Jessica | Associate Professor of Pathology and Laboratory Medicine |
| Spade, Daniel | Assistant Professor of Pathology and Laboratory Medicine |
Brown
External academic appointments
Advisory and expert committees
Editorial
| Assistant Professor. Brown University , 2026- |
| Associate. Harvard University, 2026- |
| Assistant Professor. University of Rhode Island, 2023-2026 |
Fischer teaches pharmacokinetics and toxicology to students entering biomedical and clinical research. His courses cover ADME fundamentals, pharmacokinetic and pharmacodynamic modeling, precision medicine and pharmacogenomics, and the toxicology of everyday chemical exposures. Across all of them he emphasizes quantitative reasoning: how to move from a measured concentration to a defensible statement about what reaches a target tissue and what that means for a patient or a population.
He mentors at every level, from high school students through doctoral candidates and postdoctoral fellows. His group currently trains a cohort of ScM students on thesis projects spanning barrier assays, protein binding measurement, mass spectrometry method development, and physiologically based pharmacokinetic modeling. He has supervised six doctoral students, six master's students, and seven undergraduate researchers, and he co-organized the Rhode Island Nano-Bio Engineering Academy, a hands-on research event for local high school students.
Courses taught include ADME-Pharmacokinetics Fundamentals, Pharmacokinetics and Pharmacodynamics for Scientists, Precision Medicine and Applied Pharmacogenomics, and Toxic or Not?, a general education course on chemical exposure and health. He has also lectured on chemical fate modeling and applied environmental toxicology at the Harvard John A. Paulson School of Engineering and Applied Sciences.
