In the McDonough laboratory, we are investigating how organic contaminants impact aquatic ecosystems and human health by combining innovative environmental chemistry and bioanalytical techniques, state-of-the-art mass spectrometry, and field monitoring campaigns. Our work protects the public from exposure to harmful pollutants and draws attention to the global ubiquity of organic contaminants.
Research Talks
Current Research Projects
Bioaccumulation-Directed Prioritization of Ionizable Organic Contaminants
With this work, our objective is to develop “virtual organisms” to rapidly isolate and concentrate mixtures of known and unknown organic contaminants in a manner representative of accumulation in biota. These strategies will facilitate rapid identification and risk-based prioritization of ionizable synthetic organic chemicals from complex chronic exposures.
To date, much of our work in this arena has focused on analyzing tissues and fluids collected after dosing mice with field-collected aqueous film-forming foam containing hundreds of known and unknown per/polyfluoroalkyl substances (PFASs). The figure below (from McDonough et al., ES&T 2020) highlights a series of bis-perfluoroalkyl sulfonimides tentatively identified in the serum of AFFF-dosed mice though they were not detected in the original dosing mixture, suggesting that these previously overlooked chemicals are highly bioaccumulative.
Currently we are delving into in vitro techniques to further probe the processes occurring in the body and applying these ideas to a broader range of questions, including consideration of other ionizable organic contaminants besides PFASs and prioritization techniques in highly complex contaminated aquatic environments (SERDP Project ER22-4003).
Related Publications
Dukes, D. A.; McDonough, C. A. 2024. N-glucuronidation and excretion of perfluoroalkyl sulfonamides in mice following ingestion of aqueous film-forming foam. Environmental Toxicology & Chemistry, e00224. DOI: 10.1002/etc.5939
McDonough, C. A.; Scott, W. 2023. Tackling PFAS complexity with HRMS and Bioanalytical Techniques. LCGC Supplements: Hot Topics in PFAS, 41(s9), 12-16. DOI: 10.56530/lcgc.na.nr4267c9
McDonough, C. A., Choyke, S., Ferguson, P. L., DeWitt, J. C., Higgins, C. P. 2020. Bioaccumulation of novel per- and polyfluoroalkyl substances in mice dosed with an aqueous film-forming foam. Environ. Sci. Technol., 54, 5700-5709. DOI: 10.1021/acs.est.0c00234.
Widening the Lens on Organofluorine in Human Serum
Pre-PFAAs are PFASs that can potentially degrade to form highly persistent perfluoroalkyl acids (PFCAs and PFSAs) as their final product (McDonough et al., ES&T, 2022). Their bioavailability, toxicokinetics, and toxicology have not been studied extensively. The OECD has classified the majority of PFASs (4,186 out of 4,730 PFAS-related CAS numbers) as “potential precursors to PFAAs.” Pre-PFAAs make up a significant portion of historical and modern AFFFs. They are also used in a wide variety of consumer and industrial products encountered by the general public. We are working to measure much needed distribution coefficients and gather information on biological transformation rates and transformation products for these precursors.
We are also widening the lens on unidentified organofluorine by developing and optimizing new workflows for human biomonitoring. This includes ongoing work to develop improved methods to measure short-chain PFASs in human urine (funded by CDC NIOSH) and HRMS strategies to identify novel PFASs in human blood.
Related Publications
Perera, D.; Scott, W.; Smolinski, R.; Mukhopadhyay, L.; McDonough, C. A. Techniques to characterize PFAS burden in biological samples: Recent insights and remaining challenges. Trends in Environmental Analytical Chemistry, 2024, 41, e00224. DOI: 10.1016/j.teac.2023.e00224
McDonough, C. A.; Li, W.; Bischel, H. N.; De Silva, A. O.; DeWitt, J. C. Widening the lens on PFASs: Direct human exposure to perfluoroalkyl acid precursors (pre-PFAAs). ES&T, 2022, 56(10), 6004-6013. DOI: 10.1021/acs.est.2c00254
McDonough, C. A.; Choyke, S.; Barton, K. E.; Mass, S.; Starling, A. P.; Adgate, J. L.; Higgins, C. P. Unsaturated PFOS and other PFASs in human serum and drinking water from an AFFF-impacted community. ES&T. 2021, 55(12), 8139-8148. DOI: 10.1021/acs.est.1c00522
Barton, K.; Starling, A.; Higgins, C. P.; McDonough, C. A.; Calafat, A.; Adgate, J. Sociodemographic and behavioral determinants of serum concentrations of per- and polyfluoroalkyl substances in a community highly exposed to aqueous film-forming foam contaminants in drinking water. Int. J. Hyg. Environ. Health. 2020, 223(1), 256-266. DOI: 10.1016/j.ijheh.2019.07.012
PFASs in Benthic Biota Exposed to Impacted Marine Sediments (SERDP ER22-4003)
PFAS contamination in marine sediments poses significant risks to benthic organisms and trophic transfer within coastal ecosystems. This issue is particularly pronounced at sites impacted by aqueous film-forming foams (AFFF), where PFASs exist as complex mixtures. Our research aims to address critical knowledge gaps by: 1. Investigating how key variables—sediment characteristics, PFAS molecular structure, and mixture complexity—affect PFAS bioavailability, uptake, and bioaccumulation in major benthic organisms (e.g., worms, clams, fish, and crabs). 2. Assessing the role of diet as a pathway for PFAS exposure in benthic consumers. 3. Determining the relative toxicity of individual PFASs and PFAS mixtures on the survival and development of larval-stage benthic species.
To achieve these objectives, we are conducting laboratory-controlled exposure experiments using both laboratory-spiked and field-collected marine sediments with varying PFAS mixture complexity. Preliminary findings suggest that HLB solid-phase microextraction (SPME) blades show significant potential for monitoring bioavailable PFAS concentrations in complex environmental matrices. Additionally, we have observed that PFAS potency varies with chain length and functional groups across multiple ecological endpoints. Our ongoing research focuses on further exploring the mechanisms of adsorption and the utility of SPME for measuring bioavailability, aiming to advance our understanding of PFAS behavior at sediment-biology interfaces.
Past Projects
Depth profiles of Organophosphate Flame Retardants in the Remote Ocean
Dissolved organophosphate esters and polybrominated diphenyl ethers in remote marine environments: Arctic surface water distributions and net transport through Fram Strait
Passive sampling to Understand Contaminant Dynamics in the Great Lakes
Spatial distribution and air–water exchange of organic flame retardants in the Lower Great Lakes
Significance of Population Centers As Sources of Gaseous and Dissolved PAHs in the Lower Great Lakes
I am a new Ph.D. student in the Department of Chemistry at Carnegie Mellon University. As an undergraduate, I studied both chemistry and chemical biology, and my research focused on the effects of the environment on archaeological samples. I’m looking forward to transferring those lab skills to studying the effects of per/polyfluoroalkyl substances (PFAS) on the environment and biological systems. When I’m not in the lab, I enjoy horseback riding, reading, and hiking!
I am currently a first year Ph.D. student in the Chemistry Department at Carnegie Mellon University. I have a background in Environmental Science (Siena College, B.S.) and am interested in the fate of organic contaminants in the environment. I am particularly interested in the bioaccumulation of per/polyfluoroalkyl substances (PFASs) throughout aquatic food webs and aquatic ecosystems. Outside of the lab, I enjoy reading, embroidery and spending time outside!
I am a rising second-year PhD student in the Department of Chemistry at Carnegie Mellon University. I earned my M. Phil degree from Hussain Ebrahim Jamal Research Institute of Chemistry at the University of Karachi, Pakistan. During my previous research, I focused on method development using HPLC-ELSD to rapidly screen secondary metabolites derived from plants.
I am an environmental chemist from India, currently in the second year of my Ph.D. at Carnegie Mellon University. I am interested in the fate of organic pollutants in the environment and my work focuses on understanding per- and polyfluoroalkyl substances (PFAS) contamination trends in aquatic animals and environments. I am working on evaluating passive sampling strategies to measure the bioavailable fraction of PFAS in marine sediments. Outside of working in the lab, I enjoy badminton, hiking, and hanging out with my dog, Rocket!
Morgan Van Der Linde
Yanan received her M.S. and Ph.D. degrees in Environmental Engineering from Fudan University, China. She also completed an 18-month joint-Ph.D. training program at Aalborg University, Denmark. Her research focuses on the environmental fate, risks, and degradation mechanisms of emerging environmental micropollutants, including DBPs, PPCPs, and microplastics.
Dilani received her B.S. degree (with honors) in Chemistry from the University of Colombo, Sri Lanka in 2016, and her M.S. and Ph.D. degrees in Chemistry from the Florida International University in 2021 and 2022, respectively. She joined the McDonough lab in 2023 as a postdoctoral scientist.
I am a Fulbright-Nehru Postdoctoral fellow working in the area of Environmental chemistry and engineering at the McDonough lab, Department of Chemistry, Carnegie Mellon University. I received PhD in Soil Science and Agricultural Chemistry from Indian Agricultural Research Institute, New Delhi, India (2018). Prior to joining McDonough lab, I was a Soil Scientist at Central Soil Salinity Research Institute, Karnal, India. Currently, my research works focus on development of engineered clay mineral adsorbents using naturally available clay minerals and biowastes to remove PFAS from contaminated water and reducing PFAS bioavailability in food crops, deciphering an inexpensive and green PFAS remediation method.
I am a chemical oceanographer and analytical chemist working at the intersection of environmental analytical chemistry, environmental health engineering, and toxicology. I received my B.Sc. in Chemistry from the Massachusetts Institute of Technology (MIT) in 2008, and my Ph.D. in Chemical Oceanography from the University of Rhode Island Graduate School of Oceanography (URI GSO) in 2017. I completed a postdoctoral fellowship at Colorado School of Mines developing methods for nontarget analysis of per/polyfluoroalkyl substances (PFASs) in biological samples. I use cutting-edge environmental monitoring and analytical chemistry techniques to study the fate, transport, and biological effects of anthropogenic organic contaminants in aquatic environments. Broadly, I am interested in how the molecular structure and chemical properties of pollutants influence their fate in the environment, as well as their biological effects in aquatic organisms and humans. My overarching objective is to understand human and ecosystem health risk associated with organic contaminants in water and to identify particular compounds of concern that should be prioritized for remediation and toxicological investigation. When I’m not working, I am usually brewing beer and hanging out with my dogs, Millie (pictured here) and Pickles.
