Advancing Water Analyses
Presenting new considerations to evaluate drinking water.
Lisa Holland, Vince Remcho, Susan D. Richardson, Vicki Blazer |
Water is life. Indeed, its existence on Mars has driven the search for life on the red planet (see Art of Analysis). Water is also a powerful solvent, carrying a myriad of chemicals, many of which undergo chemical conversion in the resulting complex mixture. Importantly, the quality of water entering a processing facility can affect the purity of the polished product. But, how much control do we have? Monitoring water and limiting toxic chemicals introduced into our water system can improve the process, and regulations govern what we know to be dangerous. However, there is a struggle to predict what new contaminants should be restricted.
At Pittcon 2015, we presented the conundrum of water quality in our session on emerging contaminants and healthy water. At the University of South Carolina, exquisite analyses based on chromatographic separation and high-resolution mass spectrometry provide powerful insight into the complex and dynamic mixture that is our municipal water. Analyzing water for pharmaceuticals, illegal drugs, food additives, pesticides, herbicides, and consumer products can reveal much. For example, penta and octa brominated contaminants (originating from polybrominated diphenyl ethers once used in flame-retardants) are toxic (1). A deca-brominated contaminant should be safe, except that it degrades to these more toxic constituents (1). So we must ask: “Is this an isolated problem?” Perhaps not.
Iopamidol is an invaluable imaging agent in medicine; it is safe for consumption and improves lives. Yet, when it is excreted by the body and subjected to chlorination, a 200-gram dose of a critical medical chemical becomes a toxic iodinated disinfection by-product (2). How could this have been anticipated? If we put the power of an LC-MS into a wastewater treatment facility, the operator would know, but such equipment and knowledge comes at a cost.
What if we reduced the cost by using non-toxic, disposable microfluidics to make simple and robust sensors? This would allow the operator to identify those species that are intolerable in the water system, those that can be better removed with changes in processing, and those that are indicators of anthropogenic contamination of natural waters. When knowledge is power, such strategies make sense.
At Oregon State University, researchers use polycaprolactone to build portable devices by printing simple patterns on laboratory filter paper (3, 4). The work – supported by the Bill and Melinda Gates Foundation – paints an interesting picture; colorimetric assays for bromide using the technology, for example, can easily recognize the yellow spots of hydraulic fracturing (fracking) fluid leakage. Paper is cheap and the human eye is the ultimate convenient detector. The measurement can be performed on a tight budget for less than one dollar with no training required. And, for an additional 100 dollars, a stable light source and USB adapter can be added to the device to improve quantification; another option is to use a mobile phone for detecting and data sharing. With these relatively low-cost tools, on-site monitoring becomes achievable for bromide and the principle may be applied to any other contaminant that can be adapted to colorimetric detection.
But let’s return to the question about what is not known. There are 800 known endocrine disrupting compounds, but the bigger threat comes from those compounds, metabolites or mixtures for which toxicity is not yet known. In our waterways, for example, dying freshwater fish tell us when agricultural runoff, antibacterial additives in soap, or pharmaceuticals excreted by humans, lead to a toxic recipe for aquatic life. So, we can learn a lot by monitoring wildlife. Population declines or sudden die-offs can be signs of caution, as can indicators of reproductive dysfunction, compromised immune systems, cancer, neurotoxicity and behavioral effects in fish living in these waters. Sediment, water, passive samplers, and fish may hold secrets that led a U.S. Geological Society (USGS) research team to assay 138 chemicals collected from samples at six different sites throughout the Potomac River basin – which supplies water to more than five million people in Maryland, Pennsylvania, Virginia, Washington D.C., and West Virginia in the USA (5, 6).
What can be done when human activities create chemical cocktails in our water system? Researchers at West Virginia University demonstrated the power of analyzing circulating steroids in fish by using a rapid capillary electrophoresis method to separate multiple steroids within five minutes, enabling detection of steroids in individual fish using UV-visible absorbance (7). When adapted for the analysis of a single zebrafish weighing only 1.5 grams, this method generates nanomolar detection limits and provides insight into hormonal responses to chemical exposure that correlates well with physiological endpoints. Monitoring changes in multiple circulating steroids enables researchers to screen chemicals rapidly for endocrine disruption. With information about specific changes in estrogens, androgens, and progestogens, the mechanisms of dysfunction can be better elucidated.
After we presented the above examples in our Pittcon session, we had a lively panel discussion, which increases the likelihood that this topic will be included in other national and international meetings. Being able to show how integrating technologies and how analytical chemistry can tackle such a complex problem, such as water safety, fires debate and, above all, we hope that scientists and citizen scientists will seek answers to these environmental issues with new enthusiasm. Certainly, further research must be supported to address these important questions (8).
- S. D. Richardson and T.A Ternes, “Water Analysis: Emerging Contaminants and Current Issues”, Analytical Chemistry, 86 (6), 2813-48 (2014).
- S. E. Duirk et al., “Formation of Toxic Iodinated Disinfection By-Products from Compounds Used in Medical Imaging”, Environmental Science & Technology, 45(16), 6845-54, (2011).
- M. T. Koesdjojo et al., “Cost-Efficient Fabrication Techniques for Microchips and Interconnects Enabled by Polycaprolactone”, Journal of Micromechanics and Microengineering, 22(11):115030 (2012).
- M. T. Koesdjojo et al., “Low-Cost, High-Speed Identification of Counterfeit Antimalarial Drugs on Paper”, Talanta, 130(0), 122-7 (2014).
- L. R. Iwanowicz et al., “Reproductive Health of Bass in the Potomac, USA, Drainage: Part 1. Exploring the Effects of Proximity to Wastewater Treatment Plant Discharge”, Environmental Toxicology and Chemistry, 28(5), 1072-83 (2009).
- D. A. Alvarez et al., “Reproductive Health of Bass in the Potomac, USA, Drainage: Part 2. Seasonal Occurrence of Persistent and Emerging Organic Contaminants”, Environmental Toxicology and Chemistry, 28(5), 1084-95 (2009).
- V. T. Nyakubaya et al., “Quantification of circulating steroids in individual zebrafish using stacking to achieve nanomolar detection limits with capillary electrophoresis and UV-visible absorbance detection”, Analytical and Bioanalytical Chemistry. epub ahead of print, DOI 10.1007/s00216-015-8785-0 (2015).
- P. J. Novak et al., “On the Need for a National (U.S.) Research Program to Elucidate the Potential Risks to Human Health and the Environment Posed by Contaminants of Emerging Concern”, Environmental Science & Technology, 45(9), 3829-30 (2011).
Lisa Holland received her BS degree in Chemistry from the University of Maryland at College Park, while working in the Electroanalytical Research Group at the National Institute of Standards and Technology. She received her PhD in Chemistry from the University of North Carolina at Chapel Hill under the direction of James Jorgenson. Through a National Research Service Award she held a postdoctoral fellowship under the direction of Susan Lunte in the Department of Pharmaceutical Chemistry at the University of Kansas. Holland is the recipient of a National Science Foundation Faculty Early Career Development award, has served on the scientific committee of national and international conferences, and has numerous publications in the field of separation chemistry. She was elected to the executive board of the American Chemical Society Subdivision of Chromatography and Separation Chemistry, is currently the Chair elect. She holds a faculty position in the C. Eugene Bennett Department of Chemistry at West Virginia University, specializing in microscale separations of biomolecules relevant to human health. She enjoys teaching instrumental analysis to undergraduate and graduate students and mentoring the many outstanding graduate students who have studied separation science at WVU.
Vince Remcho is Oregon State University’s Patricia Valian Reser Faculty Scholar, Professor of Chemistry and Professor of Materials Science. He holds adjunct appointments in Biochemistry & Biophysics and Industrial & Manufacturing Engineering. His research group works at the interface of science and engineering to design, fabricate ad optimize microscale analytical instruments and chemical reactors. These systems are applied in biochemical, environmental, and nanomanufacturing problem solving. Research support has come from NIH, DOE, NSF, the Air Force, Army and Naval Research Laboratories, the W.M. Keck Foundation and the Murdock Charitable Trust. He is the recipient of an NSF CAREER Award, was recognized with the Milton Harris Award for Research Excellence (2010),is a Fellow of AAAS (2014), was elected Oregon Scientist of the Year (2015), and has been recognized for teaching excellence. He received his BS (Biochemistry, 1989) and PhD (Chemistry, 1992) from Virginia Tech, where he worked with Harold M. McNair. He was a postdoctoral fellow at the University of Utah and the Pacific Northwest National Laboratory working with J. Calvin Giddings and Nathan E. Ballou.
Susan D. Richardson is the Arthur Sease Williams Professor of Chemistry in the Department of Chemistry and Biochemistry at the University of South Carolina. Prior to coming to USC in January 2014, she was a Research Chemist for several years at the U.S. EPA’s National Exposure Research Laboratory in Athens, GA. For the last several years, Susan has been conducting research in drinking water – specifically in the study of toxicologically important disinfection by-products (DBPs). Susan is the recipient of the 2008 American Chemical Society Award for Creative Advancements in Environmental Science & Technology, has received an honorary doctorate from Cape Breton University in Canada (2006), serves as an Associate Editor of Water Research and on the Editorial Advisory Board of Environmental Science & Technology, Rapid Communications in Mass Spectrometry, Journal of Hazardous Materials, and Environmental Science and Pollution Research. Susan has published more than 115 journal articles and book chapters and has written two ongoing invited biennial reviews for the journal Analytical Chemistry—on Emerging Contaminants in Water Analysis and Environmental Mass Spectrometry, She has a PhD in Chemistry from Emory University and a BS in Chemistry & Mathematics from Georgia College & State University.
Vicki Blazer received her BS in Marine Science and Biology from Southampton College of Long Island University and her PhD in Fisheries, Aquaculture and Pathology from the University of Rhode Island. After completing a postdoctoral position in Medical Microbiology at the Veterinary College, University of Georgia, she accepted the Assistant Leader position with the Cooperative Fish and Wildlife Research Unit in the School of Forest Resources, where she taught Fish Diseases, Fish Nutrition and Fish Pathology and directed graduate student research. Since coming to her current position as a Research Fishery Biologist at the US Geological Survey’s National Fish Health Research Laboratory in Kearneysville, WV, she has continued to teach classes and direct graduate student research. She is an adjunct professor at West Virginia University, Penn State University and Shepherd University. Her current primary research interests are understanding the influence of environmental stressors (climate, contaminants, parasites, pathogens) on the health of fish populations and utilizing fish health biomarkers as indicators of ecosystem health. Her major projects are in the Chesapeake Bay and Great Lakes watersheds and include understanding the sources, pathways and effects of endocrine disruptors and other contaminants of emerging concern.
