Emerging investigators: profiles of the contributors

Environmental Science: Processes & Impacts is committed to supporting early career scientists, and it is because of this that we are both proud and very pleased to introduce the third edition of our emerging investigators issue, which celebrates the best and brightest amongst early career environmental scientists around the world. To introduce our contributors, we asked each of them a set of questions regarding their personal careers and the future of environmental research. Their responses are extremely insightful, and display the great depth and variety of our contributors, and of their research interests.

This article provides more information on each contributor, including brief biographical details, and their responses to the following questions:

1. What are your ultimate research objectives that you would like to reveal in the field of your choice?

2. What do you think are the key ingredients to become a successful research leader in environmental science/engineering?

3. In your opinion, what is the greatest future environmental challenge that will need to be addressed by environmental scientists/engineers?

4. Who in environmental science/engineering inspires you the most and why?

Mohammed Baalousha

Mohammed Baalousha received a B.Sc. in Civil Engineering from the Islamic University of Gaza, Palestine in 2001. After that, he moved to France where he completed a Masters degree in Applied Mechanics in 2002 and a Ph.D. in Environmental Biogeochemistry in 2006, both from the University of Bordeaux. Between 2006 and 2013, he has undertaken a variety of postdoctoral research roles at the University of Birmingham, UK in the area of Environmental Nanoscience. In 2014, he joined the Department of Environmental Health Sciences at the University of South Carolina, SC, USA as a tenured-track Assistant Professor of Environmental Nanoscience. He is also affiliated with the Center for Environmental Nanoscience and Risk at the Arnold School of Public Health. His current research interests are centered on understanding nanoscale phenomena in the environment, including (1) understanding the fate, behavior and transformations of nanomaterials in the environment, their interaction with natural nanomaterials and their impact on conventional contaminants; (2) developing new analytical approaches to measure nanomaterials in the environment; and (3) understanding the potential environmental health concerns of manufactured nanomaterials.

1. My ultimate research objective is to develop a better understanding of nano-phenomena; their applications to improve environmental quality, but also their implications on environmental and human health. In particular, I am interested in: (1) developing a better understanding of the mechanisms controlling fate, transport and transformations of nanomaterials in environmental systems in order to predict their environmental exposure, (2) developing analytical tools to detect and quantify environmental exposure to nanomaterials, which can be used by policy makers to establish relevant measures that will protect environmental and human health, and (3) developing an understanding of the impact of nanomaterial physicochemical properties on their toxicity.

2. Environmental science is a highly interdisciplinary field, requiring collaborative effort among scientists in different scientific disciplines and in particular at the boundaries of conventional scientific disciplines. Thus, key ingredients for success in environmental science would be developing an in-depth understanding and world-class expertise in a focused research area, developing a wide understanding of other areas where your expertise can be utilized, and establishing a good professional network of scientists to collaborate with.

3. One of the greatest environmental challenges is to understand and mitigate the impact of new technologies on environmental and human health in order to avoid any unforeseen scenarios, but also to ensure the sustainability of such novel technologies and harness their benefits.

4. Throughout my education and career, I made many friends (needless to mention names here as they know themselves) rather than colleagues who inspired me in different aspects of my work, but also my life. I hereby extend my gratitude to them all.

Benjamin Barratt

Ben Barratt started his working life as a meteorologist, completing a joint degree in Physics and Meteorology at Reading University, UK. However, an M.Sc. in Environmental Engineering led to the realisation that the field of air quality improvement was more interactive and fulfilling. He went on to help establish the London Air Quality Network and assessed the impact of the Congestion Charging Scheme and Low Emission Zone in London. He obtained his Ph.D. from King's College London in 2010, followed by a lectureship in 2012. His current research work includes the development of a dynamic 3D air pollution exposure model in Hong Kong and the inclusion of air pollution exposure in public health interventions.

1. While evidence of the diverse health impacts of air pollution on human health is becoming steadily more robust, distinct causal pathways between specific pollutants and physiological outcomes remain unclear. We have a better chance of identifying these pathways if we can characterize an individual's, or a population's, exposure to air pollutants as they go about their daily lives and couple this with health metrics. I would like to utilize advances in personal health and environmental monitoring technology to identify a direct measurable link between environmental exposure and health. Such a link would be a powerful tool in awareness raising, policy development, healthcare forecasting and, ultimately, improve the length and quality of life of millions of people, which would be nice.

2. One of the key ingredients that is rarely mentioned when giving advice to people starting their research career is imagination. Unless you are extremely specialized, there will be many other researchers around the world with similar research themes trying to answer similar questions. A successful research leader needs to be able to look at those questions from a different angle, using their imagination to formulate novel methods, exploit existing datasets in fresh ways and generate proposals that spark the imagination of others. Research funding and academic positions are extremely competitive and researchers need a creative mind to recognize good opportunities when they are presented and form effective interdisciplinary collaborations.

3. In my view, the greatest environmental challenge that we will face in the future is the same challenge that we have faced since the industrial revolution and beyond; the creation and distribution of cheap, clean, truly sustainable energy. Without restrictions on power use we could make huge advancements in almost every other environmental discipline – climate change, air quality, water quality, food production, healthcare, transport etc. Micro power generation has a role to play – domestic photovoltaic panels are now a common sight across Europe – but large scale generation still has a very long way to go and most of the current solutions are sticking plasters at best.

Paloma Beamer

Paloma I. Beamer, Ph.D., joined the College of Public Health at the University of Arizona in 2007 as an assistant professor. She is an environmental engineer by training and earned her B.S. from the University of California, Berkeley and her M.S. and Ph.D. from Stanford University. Her research focuses on understanding how individuals are exposed to environmental contaminants and the health risks of these exposures with a special focus on vulnerable populations, including children, low-wage immigrant workers, and those in the US–Mexico Border Region. The ultimate goal of her work is to develop more effective interventions and policies for the prevention of avoidable cases of certain diseases such as asthma. She has received a Mentored Quantitative Scientist Award from the National Institutes of Health.

1. My scholarly activities are focused on preventing disease and health disparities by reducing environmental exposures in vulnerable populations. Therefore, I have focused on the following interrelated research questions: (1) What are we exposed to? (2) How are we exposed? and (3) What are the health effects of these exposures? Ultimately, my goal is to use my engineering skills to develop and evaluate interventions to reduce these exposures.

2. I think a strong foundation in multiple scientific disciplines and mathematics is key to being successful in the interdisciplinary field of environmental science/engineering. You also need the ability to effectively communicate complicated problems and their potential solutions with various stakeholders including fellow researchers, government agencies, and the public. After all what is the value of our research if our findings cannot be translated into effective interventions and policies to protect public health and the environment? Finally you need patience and tenacity to keep working on your research question as you face multiple challenges, and the creativity to overcome them.

3. I think one of the greatest challenges we face is how to determine what are appropriate levels of chemicals for us to be exposed to. Even though it has been almost 40 years since the Toxic Substances Control Act was passed in the US, we still have only limited data on a small number of the more than 80 000 chemicals in commercial products that also end up in our environment. As the EU moves towards stricter legislation under REACH, tools are still needed to screen and assess these tens of thousands of chemicals for their risks to humans and the environment. Until we have a better idea of these risks, it will be very hard for environmental scientists and engineers like us to design interventions to reduce these exposures and environmental impacts.

4. I have been fortunate to have great mentors in the field. I am very indebted to them and their scholarship continues to provide me with inspiration because of their creativity and passion for their work. But when I need a moment of inspiration I still go back to the 1989 speech “We must do justice” by César Chávez. Even though he was a labor activist and not a scientist, his United Farm Workers union was able to successfully develop policies to limit pesticide exposures in the fields even before the creation of the EPA. Reading this speech always reminds me of our responsibility as environmental scientists/engineers to work towards solutions for reducing environmental health disparities among those who have the least resources to control their exposures but who face a disproportionate burden of environmental contamination in their communities.

Brian Chaplin

Dr Brian P. Chaplin is an Assistant Professor of Chemical Engineering at the University of Illinois at Chicago. He holds B.S. and M.S. degrees from the University of Minnesota in Civil Engineering, and a Ph.D. from the University of Illinois at Urbana-Champaign in Environmental Engineering. He became interested in electrochemistry when he was a postdoctoral researcher in the Department of Chemical and Environmental Engineering at the University of Arizona. Research and educational activities in his Environmental Chemistry Lab are focused on novel electrochemical and catalytic processes for water treatment, with an emphasis on developing technologies that promote water sustainability.

1. My ultimate motivation for doing research is to learn as much as possible about our world and pass this knowledge on to students and colleagues. While we often measure our success by number of papers and grant money, most researchers are in this field because of a thirst for knowledge. Fulfilling this thirst is satisfying in itself, and I believe that simply focusing on learning and teaching allows all the other things that are deemed to constitute a successful research career will come naturally.

2. Although many attributes are needed to become a successful research leader, I think the most important ingredient is curiosity. For me, curiosity is what made me stay in the laboratory late at night as a graduate student and postdoc. Curiosity is also what keeps me up late at night when trying to piece experimental data together for a paper or proposal. Having curiosity allows you to work hard without knowing how hard you are actually working, and I think that attribute can also spill over to students.

3. I believe our greatest environmental challenge in the future will be a lack of fresh water supply, due to a combination of climate change and population growth. That is why I believe it is critical that as a field we continue to look for novel ways to purify water by low-cost, socially acceptable, and sustainable means. This undertaking will require collaboration amongst scientists, engineers, policy makers, and the general public. As I already see that we are making strides in this direction, I am confident that we will rise to the challenge.

4. Many people have inspired me over my career, and I try to learn something from everyone that I encounter. Probably my biggest influence in the field is Professor Vernon Snoeyink. I actually have had very little personal interaction with Professor Snoeyink, but his dedication to the field was very apparent to me while I was a Ph.D. student at the University of Illinois at Urbana-Champaign. I marveled at the numerous hours of work Professor Snoeyink logged while he was officially retired. His work ethic was an indication to me that he was truly dedicated to the field and enjoyed his work. Professor Snoeyink's actions have inspired me and many others to dedicate ourselves fully to the field of Environmental Engineering and Science.

Kai Loon Chen

Kai Loon Chen is an Assistant Professor in the Department of Geography and Environmental Engineering at Johns Hopkins University. Dr Chen completed his B.Eng. and M.Eng. degrees in Civil Engineering at the National University of Singapore in 2001 and 2003, respectively, and then went on to earn his Ph.D. from the Environmental Engineering Program at Yale University in 2008. His current research interests include the fate, transport, and effects of engineered nanomaterials in environmental and biological systems, interactions between nanoparticles and biological membranes, and utilizing nanotechnology for membrane filtration processes, water purification, and environmental remediation.

1. The research goal of our group is to identify the key parameters that control the nonspecific interactions between engineered nanomaterials and cell membranes. This information will aid the elucidation of the mechanisms for the cytotoxicity of nanomaterials and hence will enable the design and production of safer engineered nanomaterials. In addition, the understanding of nanoparticle–cell interactions will open up new opportunities for the use of nanomaterials as antimicrobial agents for biomedical and environmental applications.

2. I think it is important to work in a research area that is new and relevant to key environmental issues. A successful research leader should be able to come up with novel approaches to solve environmental problems. He/she should also be able to communicate his/her research effectively to the scientific community as well as the general public.

3. One of the key environmental challenges is the lack of access to safe drinking water. Environmental scientists and engineers have been working on different technologies that will increase the supply and improve the quality of drinking water and I feel that this is certainly an area that we can continue to contribute to.

4. My Ph.D. advisor, Menachem (Meny) Elimelech, is a great inspiration in environmental science research. His research is original and fundamental and yet applicable to the problems environmental engineers currently face, especially in the fields of membranes and environmental nanotechnology. Meny is also a dedicated mentor to his students and postdocs both current and past, and I still continue to learn from him.

Wei Chen

Wei Chen is a professor at the College of Environmental Science and Engineering, Nankai University, Tianjin, China, and an adjunct professor of environmental engineering at Rice University, Houston, Texas, USA. He received a B.S. (1992) in environmental chemistry from Nankai University, and M.S. (1997) and Ph.D. (1999) in Environmental Science and Engineering from Rice University. His current research interests include environmental processes and implications of engineered carbon nanomaterials, fate and transport of organic contaminants in the environment, and environmental nanotechnology for water treatment.

1. I would hope that the research outcomes of my work will eventually make some impacts in the remediation of contaminated environments, e.g., improving the understanding of important interfacial processes governing contaminant behaviour, or facilitating the development of new remediation technologies.

2. Personally I think two ingredients are critical at a minimum – one is always working on important problems, and the second is always being open minded, especially to unexpected results. Of course, a great leader should be able to foresee future research needs and therefore lead followers in the right direction.

3. I am not qualified to talk about this, but personally I feel that one of greatest challenges in our fields is always dealing with the complexity involved in the real environment. This often makes it extremely difficult to translate what we know in the lab to what can be done in the field.

4. My Ph.D. advisor, Professor Mason Tomson at Rice University, has played the most critical role in my career development, by teaching me how to be a real scientist.

Owen Duckworth

Owen Duckworth was born in Richmond, Virginia, to a pair of English professors. He received his B.S. in Chemistry and Geology from the College of William and Mary (1997), where he performed undergraduate research on a polluted lake and fell in love with environmental science. He went on to receive a M.S. in Environmental Science and Engineering from the University of North Carolina at Chapel Hill (2000), and a Ph.D. in Environmental Engineering from Harvard University (2003). After working as a postdoctoral scholar at the University of California, Berkeley, he accepted a position as an Assistant Professor of Soil Biogeochemistry in the Soil Science Department at North Carolina State University, and was promoted to Associate Professor in 2013. His current work probes the interactions between microbes, minerals, and contaminants in soils, sediments, natural waters, and engineered systems.

1. I am fascinated by the molecular connections between organisms and the inorganic world. Understanding how microbes derive energy and nutrition from minerals is at the heart of many environmental processes.

2. I think that curiosity is a key trait for researchers. Although mission-driven science is important, many big discoveries have come from exploring the curiosity-driven projects that individual scientists are passionate about. These “pet projects” often contain your most creative ideas and result in fascinating science.

3. The biggest challenge will be feeding and supplying water to a population of approximately 9 billion by 2050 while preserving human health, wilderness and recreational areas, species diversity, and other natural resources.

4. Clair Patterson and Linus Pauling strike me as important and courageous figures with profound scientific and societal legacies.

Julian Fairey

Julian Fairey was born in Chilliwack, British Columbia, Canada, in 1977. He received a B.S. in Civil Engineering from the University of Alberta in 2000 and M.S. and Ph.D. degrees in Civil Engineering from The University of Texas at Austin in 2002 and 2006, respectively. Following a two-year post-doctoral position at Carnegie Mellon University, he joined the Department of Civil Engineering at the University of Arkansas as an Assistant Professor. His research group focuses on various aspects of physico-chemical treatment processes, with an emphasis on disinfection byproduct formation and control and development of sorbent-based processes for water purification.

1. The overarching objective of my research program is to discover novel materials and processes to curb formation of disinfection byproducts (DBPs) in drinking water. At present, my lab group is developing new DBP-precursor removal strategies to treat source waters enriched with nutrients from agricultural runoff and micropollutants from wastewater effluents. More long-term investigations include assessing how anticipated increases in atmospheric carbon dioxide in the coming decades might alter the abundance and reactivity of DBP-precursors in freshwaters. The goal of these studies is to help water utilities adapt existing treatment processes and integrate new ones to curb formation of regulated and toxicologically relevant DBPs.

2. In my opinion, most successful researchers, regardless of their field, have a passion for identifying and solving important problems. The inevitable ups and downs of academic research require a good deal of perseverance, patience, and humility, and must be complemented by the support of hardworking and talented colleagues, administrators, post-docs, and students. Some good luck helps too, especially in the early years of an academic career!

3. While I hardly qualify as an oracle of environmental science and engineering, a great challenge, in my opinion, lies in elevating access to water and sanitation to the some 2.5 billion people that lack these basic necessities. It would be wonderful to be part of the generation of scientists and engineers that contributes to closing this gap. Given the scale and breadth of the problem, this may require reimagining how we approach helping, both within the environmental sciences and beyond. However, as I am only now beginning to involve myself in projects related to water and sanitation in the developing world, my understanding of the underlying environmental science issues is poor, and my contributions, if any, are aspirational at best.

4. While I respect and admire a great many researchers within the environmental science and engineering community, I don't know that a particular person or group inspires me. However, I am inspired to be a small part of maintaining and perhaps improving our water treatment and sanitation systems, and to contribute to the education of the next generation of environmental scientists and engineers. The water systems operated day-in and day-out are true marvels – with all that's involved in supplying drinking water and sanitation on-demand, it's truly extraordinary that breakdowns in these systems are so rare.

Matthew Ginder-Vogel

Prof. Matt Ginder-Vogel is an assistant professor in the Environmental Chemistry and Technology program at the University of Wisconsin–Madison. Prior to joining the Madison faculty, Dr Ginder-Vogel was the manager of process and analytical chemistry at Calera Corporation. At Calera he led teams responsible for production of cementitious materials derived from industrial CO₂ sources. Previously he worked at the Delaware Environmental Institute at the University of Delaware. He received his Ph.D. in soil and environmental biogeochemistry from Stanford University. Ginder-Vogel's research seeks to define the fundamental biogeochemical processes controlling the dynamics of nutrients and contaminants within complex environmental media.

1. My research focuses on connecting macro-scale environmental problems with the causative micro- and molecular-scale mechanisms. A large portion of this research has been devoted to determining reactions controlling the fate of the metal(loid) ions chromium, technetium, uranium, and arsenic, and of nutrients/contaminants, such as carbon, nitrate and phosphate.

2. I feel the essential qualities for a successful research leader in environmental science and engineering are tenacity, a commitment to collaborating with scientists of diverse backgrounds, and an inter-disciplinary outlook.

3. I believe humans' legacy of soil and water contamination is the biggest challenge environmental scientists and engineers face.

4. My role models are Ed Lavern, my high school chemistry teacher at Little Falls Community High School in Minnesota, whose enthusiasm for chemistry was inspiring to all his students; Dave Allberg, my research mentor in chemistry at Carleton College, because of his passion for science; Scott Fendorf, my Ph.D. advisor in the Department of Environmental Earth Systems Science at Stanford, because of his reminders that everyone brings an individual approach to scientific problems; and Don Sparks, my mentor at the University of Delaware, because he embodies the idea that scientific expertise and compassion go hand in hand.

Jeremy S. Guest

Jeremy Guest is an Assistant Professor in the Department of Civil and Environmental Engineering at the University of Illinois at Urbana-Champaign (UIUC), and currently serves as the Thrust Leader for Sanitation and Resource Recovery for the Safe Global Water Institute and as the Environmental Sustainability Lead for the USAID Soybean Innovation Lab. He earned his B.S. in civil engineering from Bucknell University (2005), his M.S. in civil engineering from Virginia Polytechnic Institute and State University (2007), and his Ph.D. in environmental engineering from the University of Michigan (2012). His research centers on the development of technologies that manage wastewater as a renewable resource. By integrating experimentation, modeling, and quantitative sustainable design, Dr Guest's research group leverages fundamental insights into molecular- and cell-scale processes to advance systems-scale sustainability, connecting technology innovation with broader societal initiatives for advancing energy, food security, health and nutrition in both developing and technologically advanced communities.

1. The ultimate goal of my research group is to increase access to and the sustainability of sanitation in both developing and technologically advanced communities. Our focus is on the development of innovative technologies and management strategies that make wastewater treatment financially viable through energy production, chemical production, nutrient and water recovery. Our specific research objectives stem from critical barriers to the technologies and management strategies we develop, and span from navigating cell metabolism to the design of resilient treatment processes in an effort to advance community- and global-sustainability.

2. One of the characteristics I admire most in our field's research leaders is clarity of vision. Often I am struck by the alignment between the target outcomes for their work and the fundamental advancements they make to science and engineering. By maintaining their focus on achieving specific benefits for society, they are able to consistently make meaningful progress towards lofty goals for a safe and sustainable world through even the most basic research on small-scale phenomena.

3. Environmental challenges will continue to evolve due to the dynamic interactions between nature and society. I believe it is our role as environmental engineers and scientists to develop adaptive solutions to these evolving challenges by harmonizing societal development with long-term goals for environmental sustainability. This requires that we transition away from our focus on reactive, “end-of-pipe” mitigation and shift to a proactive role in resource management, technology and product development, and the planning and design of the built environment.

4. I have benefited tremendously from interactions with a number of leaders in our field, and each has left his or her mark on me. The two that have been the greatest source of inspiration, however, are Drs Glen Daigger (CH2M HILL) and Mark van Loosdrecht (TU Delft). Both are visionaries who have transformed the wastewater industry through their leadership and innovation, and both devote time and energy to mentor young engineers and scientists who aspire to follow in their footsteps. For these reasons and many more, I find them to be continuous sources of inspiration.

April Z. Gu

Dr Gu is an associate professor in the Civil and Environmental Engineering Department, and faculty and track leader for the Interdisciplinary Bioengineering Program within the College of Engineering at Northeastern University. She obtained her B.S. in Environmental Engineering and Science from Tsinghua University in Beijing, China and a Ph.D. in Civil and Environmental Engineering, jointly in Microbiology, from the University of Washington. Her expertise and areas of research interest include application of biotechnology for water and wastewater treatment, water quality monitoring and toxicity assessment, biosensors, microbial ecology, bioavailability of nutrients in aquatic systems and bioremediation. She serves as associate editor or editorial board member for several journals and is active as a member of international and national committees for AEESP, IWA, WEF and AWWA. She has received a number of institutional and national awards including the Søren Buus Outstanding Research Award at NEU and the NSF CAREER award. She was an invited speaker for the Gordon Conference – Environmental Nanotechnology 2013, and the Gordon Conference – Water Science in 2012.

1. To contribute to the development of feasible and effective water quality monitoring technologies for achieving the sustainability of water resources and public health protection.

2. The key ingredients to become a successful research leader in the field of environmental science and engineering include: devotion, a broad knowledge base, forward-thinking, and collaboration.

3. Global environmental issues and threats that cannot be easily addressed and will require collaboration across governmental and disciplinary boundaries.

4. Those who raise philosophical questions on the way we think and approaches we take; those who have grand visions and lead the field; and those who make fundamental breakthroughs in enabling areas.

Berat Haznedaroglu

Berat Haznedaroglu was born in Aksaray, Turkey in 1980. He received his B.Sc. in Biological Sciences from the Middle East Technical University in Ankara. He moved to the United States to pursue his graduate work and finished his M.Sc. at the Civil and Environmental Engineering Department of Villanova University, PA in 2005. His Ph.D. is from the Chemical and Environmental Engineering Department of the University of California, Riverside. Following a postdoc at Yale University, he joined the Department of Civil, Structural, and Environmental Engineering at the University at Buffalo in late 2012. Berat's overall research interests address problems pertaining to water quality and sustainable bioenergy. He specializes on the fate and transport behavior of important human and animal pathogens in aquatic environments and functional genomics of photosynthetic organisms for biofuel and value-added product applications. More information on his group and research activities can be found at: http://buffalo.edu/~berathaz.

1. My research projects generally revolve around water, energy, and food safety. Despite their vast and broad nature, I try to attack problems at their core utilizing fundamental science, and translate them into engineering solutions. Most of the research questions we try to answer are interlinked with each other; therefore, identifying the missing links and placing them in true applications is my utmost objective.

2. Accepting the fact that you would not be able to know everything. Our time-limited graduate work touches only a small portion of a research topic despite its great implications. So, I believe finding the right people who would complement your expertise is one of the keys. These people should also be people you enjoy working with, and who help you fulfill the big picture together. It is extremely important to use the best tools available in terms of sensitivity and specificity. Last but not least, listen to everybody and listen well. I keep being amazed by learning from the citizen scientists, teachers, and undergraduate students I interact with.

3. Despite advances in science and technology, we are still procrastinating on global issues such as sanitation and climate change. We need better integration between environmental concerns and socio-economic-political elements. The United Nations Environment Programme (UNEP) and UN-Habitat report 1.8 million children under five years old die from water related diseases every year. That means one every 20 seconds. This puts pressure and responsibility on all of us. I believe that our greatest challenge as environmental scientists and engineers will be to re-define sustainability with affordable, efficient, and smart water and wastewater management solutions.

4. There are numerous people whom I would not be able to name individually here. My graduate and postdoctoral advisors, colleagues at the Association of Environmental Engineering and Science Professors (AEESP), and zealous students inspire me the most as they are truly exemplary that what we do collaboratively does in fact matter and affect many.

David Ladner

David A. Ladner has studied environmental engineering since his B.S. degree at New Mexico Tech in his home state in 2003. He completed M.S. (2005) and Ph.D. (2009) work at the University of Illinois at Urbana-Champaign with Mark Clark. Ladner was a postdoc with Paul Westeroff at Arizona State University, then went to Clemson University as an Assistant Professor in 2010. Ladner's research investigates the principles behind using membranes and polymers in environmental applications, including seawater desalination, emerging contaminant removal from drinking water, and oil spill remediation. He also investigates sustainable environmental engineering processes, such as the integration of algaculture into wastewater treatment plants for nutrient recovery and energy cost reduction. His work has been funded by the US National Science Foundation, the US Environmental Protection Agency, and the US Bureau of Reclamation, among others.

1. We need infinite cycles. My grand challenge is to help move us in that direction by helping to close loops in our current environmental engineering processes. A key to this is separations: separating contaminants and salts from water, separating resources (like those in algae) from their surrounding media, and separating industrial pollutants from process streams even before they reach the effluent pipe. Finding creative, truly sustainable ways to accomplish these separations is my ultimate research objective.

2. Curiosity. When one is curious, one cannot help thinking about the interesting phenomena at play in our world. When in the shower, on the running trail, slogging through email, or whatever the location, ideas will come, conversations with others will ignite, and connections will form to find solutions to the problems one is investigating. Staying curious is a key to thriving in the field. What do you think about when you have nothing to think? If it is your science and engineering, you are on the right track.

3. I do not know if this is the “greatest” challenge, but it is one that is falling under the radar: salt. Dilution is, unfortunately, the solution we are currently applying for salt emissions. These recalcitrant materials are among the most difficult to separate, and problems with increasing salinity will need to be dealt with at some point in the future.

4. Mark M. Clark, my Ph.D. advisor, and Muriel M. Steele, my first Ph.D. student. My advisor and I are quite different, which is why he was able to teach me things I didn't expect to learn. Mark thinks deeply and creatively, and is a master at questioning assumptions and avoiding silos of thought. He gave me latitude to explore, yet the support I needed to thrive. Muriel is now, similarly, teaching me things I didn't expect to learn and is paving her path through science and engineering; equally inspiring.

David Jassby

David Jassby is an assistant professor in the Department of Chemical and Environmental Engineering at UC Riverside. Before that, David was the Executive Director of the Center for the Environmental Implications of NanoTechnology (CEINT) at Duke University. He received his Ph.D. from the Department of Civil and Environmental Engineering at Duke University. He has a M.S. in Environmental Engineering from UC Davis, and a B.Sc. in Microbiology from Hebrew University. His research focuses on water treatment technologies, environmental microbiology, and membrane separations. David hails from Israel, a country well acquainted with challenging water issues and innovative, technology-driven, solutions.

1. I was raised with water conservation and awareness drilled into my consciousness, and this has driven my research interests. Ultimately, I want to develop clever solutions to water quantity and quality issues. I am interested in new techniques and materials that are becoming available through the work of Material Scientists and Surface Chemists, and I believe that we can make a real difference in water treatment technologies using these tools. I am very interested in applying new materials and approaches to different separation processes, and in particular, membranes. Considering the growing list of undesirable chemicals in our water resources, there are many opportunities to apply innovative separation processes towards the removal of these contaminants, and I wish to be part of this effort.

2. I think the most important ingredient is curiosity. You have to be genuinely interested in what you are working on, i.e. excited. Keeping an open mind and listening to what other researchers are doing in other fields is also very important. There are many smart people out there, and it is critical to keep abreast with the latest developments in other fields; sometimes the solution to your particular problem can be found in a completely unrelated area! Also, I believe that talking to industry leaders and utility managers is a critically important ingredient to success. They are in the trenches, and can often identify key problems that need solving.

3. I think that with increased scrutiny of our water quality, environmental scientists and engineers will be asked to develop cost-effective treatment tools that are capable of delivering water that meets ever more stringent quality standards. Also, with growing populations and a changing climate, waters that were considered too “difficult” to be used as potable sources are getting a fresh look, and it is up to us to develop the next generation of technologies that will make this happen. In particular, I believe that wastewater and agricultural drainage water reuse will become more of a necessity, requiring new approaches to effectively treat these resources.

4. I am particularly inspired by individuals and groups that examine fundamental environmental phenomena, and develop models that capture and explain them. A theoretical grounding is critical for the development of sustainable environmental solutions, and I greatly admire the individuals in our field who provide fundamental insight into the processes they study.

Christina K. Remucal

Christina Remucal is currently an assistant professor in the Department of Civil and Environmental Engineering at the University of Wisconsin-Madison, where she focuses on aquatic chemistry. She is also affiliated with several interdisciplinary programs, including Environmental Chemistry and Technology, Freshwater and Marine Sciences, and Molecular and Environmental Toxicology. Dr Remucal holds a B.S. (2003) in Environmental Engineering and Science from the Massachusetts Institute of Technology and an M.S. (2004) and Ph.D. (2009) in Civil and Environmental Engineering from the University of California, Berkeley. She completed her postdoctoral research in the Institute of Biogeochemistry and Pollutant Dynamics at the Swiss Federal Institute of Technology in 2012.

1. My research focuses on providing clean water and is motivated by the deep appreciation of water I gained growing up in the high desert of northern New Mexico. My current research investigates contaminant transformation processes in both natural and engineered systems, such as photochemical reactions and advanced oxidation processes. Ultimately, I hope to develop a mechanistic understanding of these systems that can be used in water purification applications.

2. Although we often specialize in one area of environmental science and engineering, like aquatic chemistry, it is important to recognize that the systems we study are extremely messy and complicated. The water, air, soil, and biota are connected and it is impossible to separate one from another. Similarly, the complex environmental challenges we face will require interdisciplinary solutions. Because it is not possible for a single person to address these issues independently, it is necessary for researchers to develop strong collaborations that take advantage of their areas of expertise.

3. Providing sufficient quantities of clean water will be one of the greatest challenges of the 21^st century. It is a problem rooted both in quantity and quality. Population growth, changes in land use and increased demands on water used during energy production will continue to put more stress on this limited resource. A changing climate will make our water supplies less predictable due to changes in precipitation patterns and a higher incidence of extreme events. Even if we are able to meet these water challenges in the developed world, we still have not provided water to everyone on earth; one in six people worldwide currently does not have access to reliable and safe water sources. As the demand for water increases, we will be forced to turn to lower quality water sources. Environmental scientists and engineers will need to find creative solutions to address these challenges.

4. It is impossible to pick just one person who has inspired me to pursue a career in environmental chemistry. I have been extremely fortunate to have amazing mentors as an undergraduate (Tina Voelker), graduate student (David Sedlak), and post-doc (Kris McNeill). Now that the tables are turned and I am in a mentoring role, I find that my daily inspiration comes from my students. Their passion and curiosity is a great reminder of the reasons I was drawn to environmental engineering.

Pablo Ruiz

Pablo Ruiz's current research interests include exposure to pollutants in the urban environment and the associated health effects. He is also interested in the impact of climate change on the health of the population, particularly the impacts of temperature changes on susceptible populations. In a broader context he is interested in the balance of power between the members of a society, which may lead to environmental deterioration and health impacts and the political, technological and economic forces that impact this balance. Pablo is a biochemist from the University of Chile and holds a doctoral degree in Environmental Health from the Harvard School of Public Health.

1. Overall, I want to be closer to problems that involve small communities that might be affected by the “economic development” of the country. In Chile, recently we learned from our former president that there are “zones of environmental sacrifice”, which involve communities near facilities for copper production, energy production and such. I think it is a duty of us as environmental scientists to study these zones, understand their risks and dangers, communicate them to the public and advocate for improvements to protect the health of our people and children.

2. Being back in Chile for some years, I think one thing that is very important for scientists in developing countries is to learn to do good science with a reduced budget. I think it is important to be able to perform good studies in these conditions so you do not depend on large amounts of external funding from private companies. I think this gives scientists independence and lets them be closer to more relevant pollution/health problems that might affect poor communities. It is my wish as a scientist to be closer to communities with environmental challenges than to large scale projects.

3. I think the main challenge we are facing now is climate change, which in the end is a challenge regarding a change from less sustainable and unequal patterns of transport, energy production and goods production to more sustainable, healthy and green solutions. This problem has the difficult context of the level of inequalities that different countries currently have, and how these changes might increase or decrease these inequalities.

4. Globally, I think the way James Hansen has both produced relevant science regarding climate change and the way he has communicated it to other scientists, politicians and the general public is really inspiring and I wish I could have just 1% of his talent to do so.

Jonathan (Josh) Sharp

Jonathan O. (Josh) Sharp is an assistant professor in the Civil and Environmental Engineering Department at the Colorado School of Mines. Research within his laboratory focuses on the ramifications of biological processes on water quality and utilizes a multidisciplinary approach that integrates facets of environmental engineering, microbiology, hydrology, and geochemistry. In addition to exploring the implications of insect-induced tree mortality on biogeochemical processes as described in this issue, his research investigates microbially-mediated redox transformations of metals and radionuclides as well as the attenuation of trace and emerging water pollutants in engineered and natural systems. Dr Sharp lives in Golden, Colorado, USA with his wife and two young boys.

1. As someone who works at the interface of environmental engineering, microbiology and geochemistry, I am fascinated by the notion of correlating microbial composition to biogeochemical outcomes. I hope to apply this understanding to explore how microbial processes can impact our water supply and how we can manipulate environmental conditions to enhance beneficial microbially-mediated reactions.

2. The university environment is vibrant, full of enthusiasm and just plain fun; these feed into the success of its members. In terms of personal success, I would also suggest that creativity, perseverance and the ability to step outside of one's comfort zone to address challenging problems in new ways are some of the most important ingredients.

3. Ensuring clean, reliable, sustainable, and affordable water for the world's expanding population.

4. I've been exposed to so many amazing researchers in the field and have been mentored at every step of my professional development by outstanding academics. Each of these individuals inspired and helped to steer my path, and I am grateful to them all. However, if I had to choose one, it would be my father who is a soon-to-be retired professor of oceanography. He has shown me the value and synergistic nature of being an outstanding person, family member, educator, and researcher. Thanks Dad!

Elizabeth A. Stone

Elizabeth A. Stone is an Assistant Professor of Chemistry at the University of Iowa where she conducts research on atmospheric aerosols and teaches courses in analytical chemistry. Prior to her position at the University of Iowa, she was a Senior Scientist at New Mexico State University's Carlsbad Environmental Monitoring and Research Center. She holds a Ph.D. in Environmental Chemistry and Technology from the University of Wisconsin-Madison and a B.A. from Grinnell College.

1. As an atmospheric chemistry researcher, my objectives are to improve measurements of atmospheric aerosols in order to better understand their composition, sources, and transformations. In the environment, the effects of pollutants from different sources may combine synergistically, necessitating their study in complex, environmental mixtures. My research includes field sample collection, followed by chemical analysis, data analysis, and source apportionment modelling. Improved understanding of the composition and sources of PM in the atmosphere will help to reduce the uncertainty in predictions of future climate scenarios and to protect humans from exposure to environmental contaminants.

2. A successful leader in environmental science is one who is knowledgeable, passionate, creative, and innovative. They should have a forward-thinking vision, appreciation for the complexity of environmental systems, and work well in a collaborative environment.

3. In my opinion, the greatest environmental challenge that faces my generation is the mitigation of and adaptation to climate change. The impacts of climate change are diverse and span changes to the hydrologic cycle, atmospheric chemistry, agriculture, and the spread of disease. This complex global problem will require creative thinking, compromise, and interdisciplinary collaboration among scientists, politicians, educators, and the citizens of the world.

4. Rachel Carson inspired me to become an environmental scientist. Her transformative text Silent Spring enlightened me about the fate and transport of synthetic chemicals in the environment and their lasting effects many decades after their release. I continue to draw inspiration from Carson's work, particularly her ability to clearly and effectively communicate the scientific principles behind complex global environmental issues.

George Wells

George Wells is the Louis Berger Junior Assistant Professor of Civil and Environmental Engineering at Northwestern University. His research interests lie at the interface of microbial ecology and environmental biotechnology, with a particular focus on resource and energy recovery from waste, microbial nitrogen cycling and short-circuit biological nutrient removal processes, microbial ecology of engineered and impacted natural settings, sustainable biological wastewater treatment, and microbial greenhouse gas production. Prior to joining the faculty at Northwestern University, George completed Ph.D. and M.S. degrees at Stanford University and conducted postdoctoral research at Eawag – the Swiss Federal Institute of Aquatic Science and Technology.

1. The ultimate goal of my research is to leverage improved knowledge of microbial ecology to devise better microbial community management strategies that enable low-cost, sustainable environmental and public health protection, generation of renewable energy, and resource recovery from wastes. I'm particularly interested in developing and characterizing innovative, sustainable microbial bioprocesses for mitigation or recovery of nutrients from wastewater. Other research objectives that fall under the umbrella of this overall research goal include increasing our understanding of microbial greenhouse gas production and associated mitigation strategies, developing mechanisms to recover energy or higher value products from wastes or other low value feed streams, exploring implications of microbial systems biology to ecosystem function (process performance in engineering parlance), and assessing the validity of the application of classical ecological theory to engineered or impacted mixed microbial systems.

2. Passion and enthusiasm for protecting the environment and moving towards a more sustainable society; a keen sense of scientific curiosity with a capacity for outside-the-box thinking; a willingness and interest in engaging with others at all career levels in academia, the private sector, and government (particularly those in other fields); persistence and determination; a bit of “blue sky” idealism; and desire to “get one's hands dirty” are all key ingredients in my view for successful research leaders in environmental science and engineering. In my experience, leaders in our field very much display these ingredients, and are also remarkably open to mentoring and assisting emerging investigators. They also tend to have a sense of humor, particularly in the face of research setbacks, and often a good sense of work-life balance. These in my view are qualities to strive for the next generation of research leaders in environmental science and engineering.

3. Mitigation of climate change and management of the nitrogen cycle will, in my opinion, present enormous challenges in the coming decades, and thus will need to be the focus of substantial efforts by environmental scientists and engineers. These dual challenges are intimately linked to energy, agriculture, and water use (and scarcity), so environmental researchers will also need to play a key role in the development and adoption of novel renewable (bio)energy sources, safe and efficient mechanisms and technologies for reusing water, and implementation of sustainable food production practices both in rural and increasingly in urban areas.

4. An enormous number of mentors and colleagues have inspired me over the years, and indeed continue to inspire me today. There are far too many to list here, but the top of the list of inspiring members of the environmental science and engineering community are my graduate advisor (Craig Criddle), co-advisor (Chris Francis), and postdoctoral advisor (Eberhard Morgenroth). I've learned an incredible amount from all of them, and I take immense inspiration from their passion for their work, clear interest in colleagues at all levels, creativity, foresight, and generosity. Interactions with Mark Wiesner propelled me to join this field years ago as a rather naïve and idealistic undergraduate, and he continues to inspire me. In addition, Perry McCarty is an extraordinary individual directly responsible for an enormous number of advances that have truly changed the world for the better. He is also an extremely open and generous person, and is very much an inspiration to me, as he is for many in our field.

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