Environmental Science: Water Research & Technology blog

Onur Apul is an assistant professor of environmental engineering at the University of Maine. He earned his Ph.D. in 2014 in Environmental Engineering at Clemson University and his M.S. in 2009 from Turkey’s Middle East Technical University. Dr. Apul is selected to the 2022 cohort of the American Academy of Environmental Engineers and Scientists, 40 Under 40 Recognition Program. In 2021, he received the Emerging Investigator Award by Sustainable Nanotechnology Organization. In 2019, he received the “Outstanding Teacher Award” from American Society of Civil Engineers (ASCE) – Student Chapter. Dr. Apul has published more than 65 peer-reviewed journal articles and submitted 6 patent applications to date. He has given more than 100 presentations including invited keynote lectures and invited talks at national and international meetings. He is an editor of Chemical Engineering Science and early career editorial board member of Chemical Engineering Journal Advances and a member of American Chemical Society, Sustainable Nanotechnology Organization, and the Association of Environmental Engineering and Science Professors.

Read Onur’s Emerging Investigator article “Microplastic-based Leachate Formation under UV Irradiation: The Extent, Characteristics, and Mechanisms” and read more about him in the interview below:

Your recent Emerging Investigator Series paper focuses on Microplastic-based Leachate Formation under UV Irradiation: The Extent, Characteristics, and Mechanisms. How has your research evolved from your first article to this most recent article?

My PhD research focused on delineating intermolecular interactions for adsorption of organic pollutants by carbon-based materials. My training in adsorption of synthetic organic compounds inspired me to study microplastic surfaces as a new domain in aquatic environments. In the lab, we were getting familiar with microplastics, and our collaborator and EPA researcher Dr. Ateia helped us realize the importance of release of dissolved organic matter from microplastics. Overall, this study is a product of another type of interfacial interaction which gradually evolved from my PhD work.

What aspect of your work are you most excited about at the moment?

This study is only a first step of understanding interfacial interactions of microplastics in natural waters. There are other exciting and relevant research questions that we are asking to reveal this mechanism further. But personally, the ability to raise awareness and eventually mitigate this potential water quality problem, which is only recently connected to the life-cycle of plastics, excites me the most.

In your opinion, what are the most important questions to be asked/answered in this field of research?

New and advanced plastics and composites are breaking through in research and development. There are claims regarding their biodegradability, UV resistance, thermal resistance, self-healing properties. But how do these exciting material properties change the way these microplastics leach dissolved organic matter? And do we have the means to manage this additional influx of organic matter in water treatment facilities especially if you consider microplastics as widespread, increasing, non-point sources of pollution.

What do you find most challenging about your research?

Balancing the complexity of actual systems and the simplicity that we need in the lab to reveal fundamental information is the most challenging part of this research. In the environment there are so many types of plastics, different shapes, sizes, water quality metrics, biofilm coverage of these materials, mechanical interactions, diurnal variations, temperature changes. However, in the lab we are using distilled water and perfectly spherical, 3 mm beads in idealized conditions to understand very specific mechanisms. Although we learn transformative and new knowledge in simple systems, the differences between real world conditions start to make our research context disconnected. For engineers, I believe this delicate balance is universal and always challenging.

In which upcoming conferences or events may our readers meet you?

I try to attend Association of Environmental Engineering and Science Professors (AEESP) Research and Education Conferences, Sustainable Nanotechnology Organization (SNO) Conferences, American Chemical Society (ACS) Conferences, Water Quality and Technology Conference, (WQTC), Gordon Research Conferences (GRC).

How do you spend your spare time?

I try to read, listen to music, ride my bicycle, play basketball and exercise. But I am not doing a good job in balancing my time between work and play.

Which profession would you choose if you were not a scientist?

I would choose to be a lawyer. Probably because I don’t know how hard it is to be one.

Can you share one piece of career-related advice or wisdom with other early career scientists?

I would suggest learning how to manage time early on, which means learning how to say “no” to some opportunities. This would allow focusing on your research and advance more in one area. Also be kind to yourself. You are doing good!

Dr. Mengyan Li is an Associate Professor in the Department of Chemistry and Environmental Science at New Jersey Institute of Technology, specializing in environmental microbiology and biotechnology. Dr. Li received his MS and Ph.D. degrees in Environmental Engineering at Rice University. His research focuses on untangling novel microbial processes that decompose and transform emerging contaminants (e.g., 1,4-dioxane, PFAS, and antibiotics) and developing effective treatment technologies suited for municipal, industrial, and agricultural settings. To tackle frontier challenges in the water-energy-food nexus, his group synergizes modern biotechnological tools (e.g., omics, single-cell analysis, and microarray) with high-resolution mass spectrometry. Dr. Li is a recipient of the NSF CAREER Award, ISPTS Young Scientist Award, and NJIT CSLA Research Rising Star and Graduate Education Awards.

Read Mengyan’s Emerging Investigator article “environment-specific auxiliary substrates tailored for effective cometabolic bioremediation of 1,4-dioxane” and read more about him in the interview below:

Your recent Emerging Investigator Series paper focuses on Environment-specific Auxiliary Substrates Tailored for Effective Cometabolic Bioremediation of 1,4-Dioxane. How has your research evolved from your first article to this most recent article?

Fortunately, I have been working on 1,4-dioxane biodegradation and bioremediation ever since the beginning of my PhD study. Metabolism and cometabolism are two ways for microorganisms to degrade this emerging contaminant. Metabolism relies on microbes that can grow on 1,4-dioxane as the sole carbon and energy source. In contrast, microbes that cometabolize 1,4-dioxane require auxiliary substrates, such as propane and 1-propanol, to fuel the cells and stimulate the expression of 1,4-dioxane degrading enzymes. During my PhD at Rice University, I published my first article focusing on 1,4-dioxane metabolism and its implications for natural attenuation and bioaugmentation. However, bioremediation by metabolizers is challenged by several limitations for field applications. For instance, most 1,4-dioxane metabolizers tend to form clumps and exhibit low activities when 1,4-dioxane concentration is at trace level in the field. In this Emerging Investigator Series paper, we revealed that cometabolic bioremediation of 1,4-dioxane can be feasible in diverse environments. We also proved that 1-propanol can be an alternative auxiliary substrate as effective as propane when the native microbiome is low in biomass and diversity. This is a major advancement for field applications, since injection of liquid substrates like 1-propanol is more manageable and cost-efficient in deep aquifers and other 1,4-dioxane-impacted environments where injection of gaseous substrates like propane becomes less practical.

What aspect of your work are you most excited about at the moment?

I am very excited about untangling the molecular foundations for the biodegradation of 1,4-dioxane and other emerging contaminants and transform the learned knowledge to the innovation of remediation technologies to permanently remove these concerned chemicals.

In your opinion, what are the most important questions to be asked/answered in this field of research?

I think it is important to investigate (1) how to sustain and stimulate the activity of native or introduced microbes to degrade the contaminant of concern and (2) how native microbiomes and other environmental factors affect the performance of intrinsic bioremediation.

What do you find most challenging about your research?

With the assistance of state-of-the-art sequencing technologies, we are able to obtain the genomes or metagenomes of contaminant-degrading isolates or consortia, from which several putative genes can be predicted to be associated with the degradation of the contaminant. It is a challenging and tedious task to validate the function of these genes of interests though several biotechnologies (e.g., cloning and knock-out mutation) are available.

In which upcoming conferences or events may our readers meet you?

I routinely take my group to attend national and regional conferences organized by Battelle, Association of Environmental Engineering and Science Professors (AEESP), American Chemical Society (ACS), American Society for Microbiology (ASM), and Gordon Research Conferences (GRC). Internationally, I attend conferences organized by International Society for Microbial Ecology (ISME) and International Water Association (IWA). I look forward to connecting with the RSC-ES community in future events.

How do you spend your spare time?

I love nature and arts. Being located in the Metro New York area, I enjoy hiking on the Appalachian Trail, as well as exploring museums, galleries, and ethnic food around.

Which profession would you choose if you were not a scientist?

As an environmental scientist, I am looking for cures for our environment. Alternatively, I would probably work in the pharmaceutical industry to find cures for human beings.

Can you share one piece of career-related advice or wisdom with other early career scientists?

Being motivated and persistent are two driving forces for me to unravel the unknowns and innovate our traditions.

Read Oded Nir’s Emerging Investigator article “Elucidating morphological effects in membrane mineral fouling using real-time particle imaging and impedance spectroscopy” and read more about him in the interview below:

Your recent Emerging Investigator Series paper focuses on elucidating morphological effects in membrane mineral fouling using real-time particle imaging and impedance spectroscopy. How has your research evolved from your first article to this most recent article?

One of the projects I worked on during my postdoc was using acid-resistant membranes for the filtration of wastewater effluent. Although the effluent itself was not acidic, the robust membrane permitted the use of frequent cleaning with strong acid to eliminate scaling minerals. That can potentially allow reaching very high concentration on the retentate, which means higher permeate recovery and lower brine volume – a critical goal in wastewater effluent filtration. Doing the experiments, I found indications that unlike calcium carbonate, which tends to scale the membrane, calcium phosphate precipitation occurs mainly in the retentate solution, creating some kind of a cake layer. I was curious to know why it is happening, what are the crystal morphologies and the implications on fouling and cleaning, so in my lab, we took a deeper dive into mineral scaling using advanced real-time monitoring. Our findings strongly supported our early assumptions.

What aspect of your work are you most excited about at the moment?

Currently I am very excited about combining water and wastewater treatment with resource recovery, especially nutrients, through smart process designs.

In your opinion, what are the most important questions to be asked/answered in this field of research?

There is a lot of developments in the field of sustainable water treatment and resource recovery, but I think very often the question should be: is the technology or the process I developed techno-economically feasible? Or at-least, do you see a path towards techno-economical viability? We need these solutions now, not within 20-30 years.

What do you find most challenging about your research?

Bringing a technology from lab to commercial use is very challenging. The solution must be very simple, elegant, and economically attractive. Unfortunately, there is currently not enough incentive for young PI’s to push their innovations toward scale-up.

In which upcoming conferences or events may our readers meet you?

I will be giving talks in the European Desalination Society Congress (EDS 2022 Las-Palmas, Spain), and at the Nanofiltration 2022 conference in Achalem, Germany. Would be very happy to be approached by anyone interested.

How do you spend your spare time?

Mostly with my family. I also do trail running and hiking near our beautiful campus in the Negev desert

Which profession would you choose if you were not a scientist?

Has to be something creative, perhaps content creator or a musician

Can you share one piece of career-related advice or wisdom with other early career scientists?

Treat your students in the best possible way. Always listen, never get angry when making mistakes.