Low-Cost Technology Cleans Up Contaminated Sites

An innovative technology, developed with funding from the NIEHS Superfund Research Program (SRP), can deliver amendments that immobilize and degrade polychlorinated biphenyls (PCBs) in aquatic environments. The technology has proven effective in the field and resulted in millions of dollars in estimated cost savings at cleanup sites.

The Problem:

PCBs are a large and complex group of chemicals that were used in insulation, coolants, and electrical equipment. Although commercial production of PCBs was banned in the United States in 1979, they persist in the environment because of their stable chemical structure. PCBs can also accumulate in the aquatic food web, where they can pose a threat to human health.

SRP Solutions:

SediMite, developed by Upal Ghosh, Ph.D., of the University of Maryland, Baltimore County, and collaborators, uses activated carbon in the form of specialized pellets to bind to PCBs and reduce their bioavailability, or uptake by fish and other aquatic organisms. The technology can also be combined with microbes that break down PCBs, reducing their toxicity.

Documenting Effectiveness in the Field

• The approach reduces PCBs in sediment porewater and surface water in the field
• The technology lowers PCB levels measured in lake fish

Ghosh and his team collaborated with the Delaware Department of Natural Resources and Environmental Control (DNREC) to use the technology at Mirror Lake. They demonstrated that between 2013 and 2018, PCB concentrations in sediment porewater decreased by about 80% after applying SediMite. They also measured a 70% reduction in PCB levels in the lake’s fish.

Their success has important implications for human health because PCB contamination is the primary reason that fish consumption advisories are issued by DNREC and the Delaware Division of Public Health.

Building on this achievement, DNREC used an enhanced version of the SediMite technology in a new project to reduce PBCs in the Christina River. Ghosh and colleague Kevin Sowers, Ph.D., combined the activated carbon with microorganisms that can break down PCBs to both immobilize PCBs in the sediment and degrade them over time. After five months, SediMite enhanced with PCB-degrading microbes reduced the amount of PCBs in the sediment by approximately 25%. PCB concentrations decreased by around 35% in the surface water and 64% in sediment porewater.

Videos developed by DNREC depict the successes at Mirror Lake and the Christina River projects.

Building the Foundation

• Activated carbon reduces PCB bioavailability in the lab
• The technology offers significant cost savings compared to other clean-up methods

The technology builds on years of research by Ghosh and colleagues. SediMite was initially developed in part with SRP funding in an early project focused on optimizing the delivery method to apply activated carbon pellets to contaminated sites.

Ghosh had previously collaborated with Richard Luthy, Ph.D., an SRP grant recipient at Stanford University, to develop the novel concept of amending sediments with sorbents to reduce pollutant bioavailability. Their initial studies resulted in a method, patented in 2006, to stabilize persistent organic contaminants using carbon as sorbents and laid much of the groundwork for identifying potential barriers and future research needs to make the technology a viable reality, including the need for efficient methods to deliver the sorbents to sediment.

Ghosh then collaborated with Charlie Menzie, Ph.D., to develop SediMite to efficiently deliver amendments to sediments through a U.S. EPA Small Business Innovation Research program grant. Initial tests demonstrated that it was a feasible technology for use in the field. With SRP funding, the researchers scaled up their method to deliver activated carbon pellets from the lab to the field and patented SediMite in 2010.

Ghosh continued his research in a second SRP-funded project aimed at evaluating whether fish uptake less PCBs after remediation with activated carbon. The team used lab studies and modeling approaches to demonstrate that fish can reduced their PCB uptake by as much as 87% after 90 days of treatment with activated carbon.

They also showed that SediMite decreased the assimilation efficiency of PCBs by up to 93%. Assimilation efficiency measures the amount of the contaminant that remains in the body compared to the amount that is excreted. This early work by the scientists included scaling up their remediation work to the field study at Mirror Lake.

The technology was implemented in full-scale to remediate a five-acre lake in Dover, Delaware in 2013. It was also selected as a component of the cleanup strategy for a contaminated sediment site in Middle River, Maryland, where the approach was estimated to cost approximately $22 million less than traditional methods, such as dredging and hauling. 

Optimizing for Use at Scale

• Scaling up bacteria growth, dispersal, and deployment.
• Demonstrating effectiveness in the field.
• Collaborating in full-scale remediation projects.

While developing and patenting SediMite, the researchers identified some limitations to large-scale application of the technology. To address these limitations, Ghosh and Sowers, in collaboration with environmental scientist Bennett Amos, founded RemBac Environmental to enhance the SediMite carbon pellets with PCB-degrading microorganisms. Rembac was funded in 2020 through an SRP small business grant.

In the first phase of their project, they tested methods to optimize growing and storing large volumes of PCB-degrading organisms over time. They also developed and tested methods to apply the microbes more uniformly and cost-effectively to high volumes of activated carbon pellets, enabling them to scale up their technology to broader commercial use.

In the second phase of their project, the team plans to field test the effectiveness and utility of their technology at the New Bedford Harbor Superfund site. They hope their findings will inform regulators and other stakeholders as different PCB clean-up strategies are considered.

In 2022, the Elizabeth River Project started using SediMite to remediate Paradise Creek, a 14-acre tributary to the Elizabeth River in Virginia that is contaminated with PCBs. Another full-scale project, led by EPA, is using SediMite to remove dioxin from sediments in the Scanlon Reservoir in Minnesota.

SRP Funding Creates Synergy

New Directions

In 2021, Ghosh and team were awarded a four-year SRP grant to develop carbon-based sorbent materials to enhance the ability of bacteria to break down PCBs in sediments and mixtures of tetrachloroethylene (PCE) and trichloroethylene (TCE) in groundwater. PCE and TCE are chemicals often used in manufacturing and are the most frequently detected volatile organic chemicals in groundwater.

By understanding the interaction between surface chemistry and microbial degradation, the team expects to develop new technologies to remediate PCBs, PCE, TCE, and other chlorinated contaminants often found in the environment.

link to full article: 

https://www.niehs.nih.gov/research/supported/centers/srp/phi/archives/remediation/sedimite

Summer 2023 

Hennigan Lab

Developing new methods to measure atmospheric gas-phase ammonia

I am excited to deploy the instrumentation that we have been working on to collect data. It will be satisfying to see real tangible results come from something that I have worked on with other students!

The best part of my research is the people I work with, everybody in the lab is excited to be here and work on their respective projects.

Search for faculty and read about their research through their website or their department website. Then send an email to a professor who does research that speaks to you and/or aligns with your career goals.

AIChE ChemE Car Team Lead

Industry or M.S. in Chemical Engineering

https://www.linkedin.com/in/ben-welling-352602248/ 

We are now accepting applications for the third cohort of the BEMORE REU program at UMBC. 

Application Deadline:

For best consideration, please submit your applications by March 1, 2024.

The BEMORE REU program prepares students to address knowledge gaps, develop new technologies, and bring unique perspectives to complex problems in biochemical and environmental engineering and science.

Students that join the BEMORE REU Site will gain the interdisciplinary knowledge, skills, and training to address a variety of grand challenges.

Research Topics: 

•  water pollution & treatment
• sustainable plastic replacements
• smart polymers
• urban air quality
• novel biomaterials
• sustainable batteries and more. 

Additional details are available at https://bemore.umbc.edu/

Program details:

• June 3, 2024 to August 9, 2024
• $6000 stipend, travel allowance, and free on-campus housing
• Access to state-of-the-art laboratories
• Work with a diverse team of faculty and other students
• Learn about current issues in biochemical and environmental engineering and science
• Enjoy field trips, group activities, and our awards banquet

Eligibility:

• All majors are welcome to apply
• Current student at a two- or four-year college or university
• US citizen or permanent resident

APPLY NOW

Questions can be sent to  bemorereu@umbc.edu

Paul Loberg, '24 Chemical Engineering - Biotechnology & Bioengineering Track

Where was your Internship?

USALCO in Baltimore, Maryland

What is the focus of your Internship?

The focus of my internship was to develop an economical way to produce dry aluminum chloralhydrate. I am helping design and conduct experiments which would be used to advance the current R&D project through the pilot phase to a scaled up industrial version. I also did lab work to prepare and test the samples we collected from the experiments.

What are you looking forward to the most about your Internship? 

I am looking forward to returning in the winter and seeing how the project has progressed and working on it further.

What was the best part of your Internship?

The best part of my internship was the level of autonomy I was given, as an intern, by my bosses and co-workers. We had a voice during all discussions, we could make designs and sketches independently, and give our personal feedback on the project and the direction we thought it should move.

What advice do you have for students who are interested in getting involved in research or an internship?

My advice would be, even if it's late in the spring and you haven't managed to find an internship, keep applying to postings you want. I got the text for an interview during finals week while I was taking my last exam. Definitely start applying earlier if you can but don't let rejections or a lack of responses stop you.

Are you a member of any clubs/campus organizations?

I am the Treasurer of UMBC's student chapter of AIChE as well as a member of the Chemical Engineering Jeopardy team. I play basketball for the intramural CBEE team formed by ChemE students.

What are your goals after graduation?

I want to do R&D or process engineering full time.

Yoonjin Cho,

‘24 chemical engineering at Chung-Ang University, South Korea

When did you do your Internship?

Summer 2023

Where was your Internship?

Blaney Lab, UMBC

What is the focus of your Internship?

We are working to develop sampling methods for certain PFAS compounds. This is necessary as governments and regulatory agencies are actively evaluating and implementing measures to restrict the use of certain PFAS compounds and set acceptable exposure limits.

Specifically, I am working on the following projects: 

-Detection of per- and polyfluoroalkyl substances (PFAS) in wastewater, and biosolids samples. 

-Researching the impact of solution pH, temperature, and salt concentration on KPFAS Cl using membranes for passive sampler 

What are you looking forward to the most about your Internship? 

I look forward to improving my ability to read papers effectively and efficiently, as well as gaining practical experience in a laboratory setting and enhancing my data analysis skills.

What was the best part of your Internship OR What was the biggest learning moment of your Internship ?

I gave a presentation about the calibration curve and internal standard during a group meeting. At first, it was challenging to understand the concept, but through the process of looking things up in English and asking questions to team mates, it became fulfilling. Additionally, presenting in front of my colleagues in the lab pushed me out of my comfort zone. 

What advice do you have for students who are interested in getting involved in research or an internship?

Use diverse sources, including not only academic papers but also platforms like YouTube and blogs, to gain an understanding of the topic you're interested in.

Take your time looking for fields you would like but don't hesitate to take action!

Are you a member of any clubs/campus organizations?

University of Maryland-Baltimore County(exchange student)

Chung-Ang University, Korea(senior majoring in chemical engineering)

What are your goals after graduation?

Pursuing master's degree

Ethan Banks, ‘24 Chemical Engineering - Traditional Track

When did you do your Internship?

Summer 2023

Where was your Internship?

W.R. Grace in Curtis Bay, Maryland

What is the focus of your Internship?

Correlating laboratory results to easily measured in-process variables in order to improve the efficiency of production in a specialty catalyst plant.

What are you looking forward to the most about your Internship? 

Getting to learn new things in a real working environment

What was the best part of your Internship OR What was the biggest learning moment of your Internship ?

Getting to work in a manufacturing environment everyday and applying the skills learned in my classes to the real world. I really enjoyed seeing all of the unit operations and core concepts I've learned about come to life.

What advice do you have for students who are interested in getting involved in research or an internship?

Apply early and often! It can't hurt to apply to any opportunity that you may be interested in. Also, be sure to leverage your network. If you know somebody that works at a company you are interested in, don't be afraid to reach out.

Are you a member of any clubs/campus organizations?

Vice President of UMBC's student chapter of AIChE, ChemE Jeopardy Team Member, Current Teaching fellow for ENCH300, Past Teaching Fellow for ENCH225L and ENCH215, Subject Tutor for Chemical Engineering Classes at UMBC's Academic Success Center.

What are your goals after graduation?

Get a full time job in industry

Learn more about Ethan Banks: 

https://www.linkedin.com/in/ethan-banks-b3622521b/ 

About this book: 

University of Maryland, Baltimore County - Applying a Novel Symbolic Regression To Speed Up Surface Chemistry Simulations

UMBC chapter of National Society of Black Engineers (NSBE) shines at regional conference

Members of UMBC’s chapter of the National Society of Black Engineers (NSBE) traveled to Norfolk, Virginia for their annual regional conference in November and came home with numerous awards. 

The UMBC team defeated Carnegie Mellon University and North Carolina State University to win the Tech Bowl competition, a Jeopardy-style game that tests teams’ knowledge of fundamental engineering principles. UMBC also claimed first through third place in the research poster presentation contest, which involved a 10-minute technical research talk followed by questions from the judges and audience.

The team relied on prior knowledge to excel in the Tech Bowl, only having decided to participate upon arriving at the conference. “It was really exciting getting so many questions right with our only practice being from our coursework,” shares UMBC NSBE chapter president Nelanne Bolima ’24, chemical engineering. “That just goes to show how well UMBC’s College of Engineering and IT prepares students to succeed.”

In addition to Bolima, the Tech Bowl team members included Kayla Magruder ’26, chemical engineering; Saleem Lawal ’25, computer science; and Daniel Williams ’24, computer science. Presentation winners were Williams (first), Bolima (second), and Christopher Appiah ’24, mechanical engineering (third). Keith Harmon, director of the UMBC Meyerhoff Scholars Program, serves as the chapter advisor.

“We are so proud of the UMBC NSBE Chapter,” Harmon shares. “They do tremendous work supporting UMBC STEM majors and offering service impacting youth in the Baltimore-Washington corridor.”

Students supporting students

NSBE is a completely student-run organization, creating leadership opportunities for hundreds of students across the country. UMBC’s NSBE chapter supports members through activities such as mentoring initiatives, conference preparation, networking opportunities, and leadership development programming. The chapter also focuses on community outreach, such as visiting high schools, collaborating with non-profits, and welcoming younger students to shadow the chapter’s board meetings.

“I have benefitted from being a member of this team by gaining invaluable public speaking and collaboration skills,” Appiah shares. “I learned how to effectively present, detailing the broader impact of research I have done.” Appiah conducts research with Ankit Goel, assistant professor of mechanical engineering. Goel’s group works on complex applications of control theory in robotics and autonomous systems. 

For Jaden Somerville ’25, mechanical engineering, “the competition not only improved my technical skills, but also taught me teamwork, problem-solving, and effective time management.”

In March 2024, the chapter will take its talents to the 50th annual NSBE convention in Atlanta, Georgia. 

As summer wildfire smoke choked Baltimore, UMBC air pollution researchers leapt into action

Starting this May, a series of wildfires in Eastern Canada sent enormous smoke clouds wafting into the U.S., triggering air quality warnings in cities from the Midwest to the Northeast. For days, orange skies backdropped landscapes clouded by acrid air. People who could hunkered inside with the doors and windows shut. Those who had to go out faced itchy eyes, burning throats, and worse.

As a resident of the Baltimore area—which was blanketed with particularly bad smoke in both early and late June—UMBC Professor Chris Hennigan looked at the haze with dismay. But as an environmental engineer who studies air pollution, he had an additional thought: “We were looking at the air quality forecasts, and we thought ‘We have to gather data,’” he says.

The public found many colorful words to describe the summer’s unwanted smoke: brutal, eerie, dystopian.

Hennigan and his team have been working to put numbers to the adjectives. On the roof of the engineering building, the researchers installed a squat, white sensor that monitors the levels of tiny particles in the air, particularly those measuring 2.5 micrometers in diameter or less—smaller than most bacteria. Called PM_2.5, these particles are released in large numbers during fires. They are dangerous to human health because they can work their way into the deepest parts of the lungs and even enter the bloodstream.

The sensor showed huge spikes in PM_2.5 when the smoke blew through, on some days reaching levels considered unhealthy for anyone to breathe.

The researchers also set up equipment to filter particles out of the air. After 24 hours, they collected the filters, which they are storing, neatly labeled, in a refrigerator in Hennigan’s lab.

The filtered samples will advance at least two ongoing investigations, Hennigan says. In one avenue of inquiry, Joel Tyson, Ph.D. ’23, biochemical engineering, is studying how tiny particles can harm human lung cells. Before this year’s smoky summer, Tyson had been studying the toxic effects of particulate matter normally found in the Baltimore air. With the new smoke samples, he will start to investigate whether wildfire smoke particles, per unit, are more toxic than regular urban particulate matter, which comes from sources such as cars and power plants. Some studies have indicated that wildfire particulate matter is indeed more toxic, but more research is needed before any definitive conclusions can be reached.

In another line of research, Hennigan is also studying how particles in the air, including from smoke, may affect the climate. Undergraduate chemical engineering students Danielle Larios ’25 and Luis Rodriguez ’25 are assisting in the investigations.

The researchers study how particles of brown-colored carbon-containing material absorb light. Burning vegetation sends large amounts of this brown carbon into the atmosphere. It’s possible that the particles are trapping significant heat from the sun, accelerating the pace of planetary warming. Such effects are not normally included in global climate models, and better understanding of the process could improve humanity’s ability to predict, and manage, the coming years of climate upheaval.

Climate change and wildfires are intimately linked. This summer was not only smoky, but also scorching. July marked the hottest month ever recorded, and scientists predict that as the world continues to warm, wildfires will continue to increase in quantity and intensity. “Smokeageddon,” as headlines put it, may become the new normal.

Hennigan says recent research illuminates how much wildfire smoke has contributed to air pollution trends. He points to a paper published in September in the scientific journal Nature that estimated that since 2016, wildfire smoke in the contiguous United States has undone around 25% of the progress in air quality made between 2000 and 2016.

For the researchers in Hennigan’s lab, those effects have been felt personally. 

Rodriguez recalled how in June he had to go out to buy a fresh pack of N95 masks. “The smoke was just awful,” he says. Larios says she felt a burning at the back of her throat in just 15 minutes walking to her car.

For Tyson, the effects of the smoke were so bad that at one point he struggled to breathe and had to visit the doctor. The episode, he says, drove home the importance of his toxicology research.

All three note both the complexity of the systems they are studying and the importance of discovering new knowledge that might help society handle the environmental challenges it faces.

“Our work can have real-world impact, and that’s exciting,” says Larios.