Superfund Research Program
- Sunderland Discusses PFAS Research at ATSDR
- Successful SRP Webinar Series Focuses on Toxicity Testing
- Distinguished Lecture Highlights Mechanisms of Liver Cancer
- Public Webinar Outlines Latest PFAS Exposure and Health Research
- EPA Adds Six Hazardous Waste Sites to the National Priorities List
- SRP Brings Solution-Oriented Science to SOT
- SRP Grantee Presents NIEHS Seminar on Clinical Intervention for Pain
- Trainee Research Featured in the SRP Poster Winners Webinar
- Eight Northeast SRP Centers Convene at Regional Meeting
- Workshop Takes Next Steps with Lancet Commission Report
- Iowa SRP Center Model Enables Accurate Air Pollutant Measurements
- SRP Researchers Create Ultrastretchable Nano Barrier for Numerous Applications
- SRP Grantees Work to Improve Water Quality for Native Communities
- SRP Grantees Participate in Federal PFAS Information Exchange
- Improving Site Characterization to Assess Contaminant Removal
- SRP Research Finds Ancestry-Based Differences in Telomere Length Genes
- SRP Grantee Featured in Science Friday Video
- Fish Adaptation to TCDD Seen at the Genome Level
- SRP Grantee Takes Cleanup Technology to the Field
Sunderland Discusses PFAS Research at ATSDR
At a May 10 seminar, Elsie Sunderland, Ph.D., described her research efforts to understand how people are exposed to poly- and perfluoroalkyl substances (PFASs) and to develop quantitative tools tracing PFAS exposures back to their sources. PFASs are a large group of manufactured compounds that have been widely used since the 1950s to make everyday products more resistant to stains, grease, and water. In animal studies, some PFASs have been shown to disrupt endocrine activity, reduce immune function, and bring about developmental problems.
Sunderland's talk at the Agency for Toxic Substances and Disease Registry (ATSDR) in Atlanta was part of the SRP-ATSDR Seminar Series. Hosted by the NIEHS Superfund Research Program (SRP), ATSDR, and the National Center for Environmental Health, the seminar was followed by a lunch discussion and afternoon meetings with staff from ATSDR and other local partners. The SRP-ATSDR seminars highlight the most recent SRP research results relevant to ATSDR and help SRP scientists identify potential future research needs.
Sunderland, an associate professor at the Harvard School of Public Health and project leader at the University of Rhode Island SRP Center, described how her team uses novel statistical methods to link PFASs measured in surface waters and fish to their sources. She also explained how they are using these methods to analyze human serum data to understand which sources of PFASs contributed most to human exposures. They have found that while seafood was an important source for some types of PFASs in certain populations, consumer products were the largest source of PFASs overall.
Successful SRP Webinar Series Focuses on Toxicity Testing
In the spring 2018 Risk e-Learning webinar series, Superfund Research Program (SRP) grantees and colleagues featured research and technologies that may be useful for evaluating the safety of chemicals. These approaches aim to replace or reduce the use of animal models, test more chemicals in a shorter period of time, and generate findings that are more relevant to humans. In total, this series attracted 1,022 live participants, 420 online archive views, and 3,128 video podcast downloads.
On the May 14 kickoff session, Toxicity Testing Strategies and Model Systems, presenters provided an overview of toxicity testing strategies to advance the use of 21st-century science in chemical safety evaluation. Speakers also described the pros and cons of model systems, such as zebrafish and cell-based assays, to explore chemical safety. Presenters included Nicole Kleinstreuer, Ph.D., deputy director of the National Toxicology Program's Interagency Center for the Evaluation of Alternative Toxicological Methods; Lisa Truong, Ph.D., a member of the Oregon State University SRP Center; and April Rodd, Ph.D., a postdoctoral researcher at Brown University and a former Brown SRP Center trainee.
The May 23 session, Tools for Assessing Exposure and Toxicity, outlined how toxicity data from one chemical may be used to identify other potential toxicants. Presenters also explored rapid screening tools to assess chemical contaminants in the environment and highlighted genetic screening tools to examine mechanisms of toxicity. Presenters included James W. Rice, Ph.D., a former SRP trainee who now works at Gradient; Erin Baker, Ph.D., a Pacific Northwest National Laboratory researcher and member of the Texas A&M University SRP Center; and Chris Vulpe, M.D., Ph.D., a professor at the University of Florida and a University of California, Berkeley SRP Center collaborator.
The final session on May 31, Modernizing Safety Testing, focused on new and emerging strategies for chemical safety evaluation. The discussion included work to understand how studies using animals, cells, and computer models can address population variability and how in vitro high-throughput assays can provide useful information for assessing the safety of complex mixtures. Presenters included SRP Director Bill Suk, Ph.D.; Weihsueh Chiu, Ph.D., leader of the Texas A&M University SRP Center’s Decision Science Core; and Michael DeVito, Ph.D., acting chief of the National Toxicology Program Laboratory.
More details and archives of each session are available on the SRP Risk e-Learning series page. Risk e-Learning webinars are conducted by the SRP in collaboration with the U.S. Environmental Protection Agency (EPA) Office of Land and Emergency Management. The two-hour sessions focus on sharing innovative treatment and site characterization technologies with EPA risk assessors and regional project managers, state and local regulatory agencies, environmental engineering and consulting firms, and academia.
Distinguished Lecture Highlights Mechanisms of Liver Cancer
In a May 15 seminar at NIEHS, Michael Karin, Ph.D., detailed the sequence of molecular changes in the liver that eventually lead to liver cancer. Karin, a Distinguished Professor of Pharmacology and Pathology at the University of California, San Diego (UCSD) School of Medicine, is part of the UCSD Superfund Research Program (SRP) Center.
SRP Director Bill Suk, Ph.D., hosted the talk. In his introduction, Suk explained that Karin has studied the relationship between inflammation, cancer, and metabolic disease at UCSD since 1986.
The Karin group is interested in nonalcoholic steatohepatitis (NASH), one of the more serious illnesses in a group of metabolic disorders known as nonalcoholic fatty liver disease (NAFLD). NAFLD, which affects one-third of U.S. adults, starts as simple fatty liver, but 10–15 percent of patients will develop NASH.
"The factors that control the switch from simple fatty liver to NASH are not clear," Karin said, "but we speculate that it is associated with stress in a part of the cell called the endoplasmic reticulum (ER)."
The ER is a network of tubules in plant and animal cells that produce lipid and proteins. Karin and his colleagues decided to test the hypothesis that the ER was involved using mice that are more likely to develop ER stress in the liver.
In these mice, Karin and his colleagues revealed that a high-fat diet increases ER stress, which activates proteins that increase the production of cholesterol and fatty acids. This process gives rise to cell death and inflammation and, ultimately, the progression from simple fatty liver to NASH.
"Not only does Karin’s work in mice provide a new model for understanding the development of NASH, but it may also uncover what happens in the steps from NASH to liver cancer," said Suk.
Public Webinar Outlines Latest PFAS Exposure and Health Research
New information on per- and polyfluoroalkyl substances (PFAS) in drinking water and potential health effects was the focus of a May 1 Collaborative on Health and the Environment (CHE) webinar. The webinar was co-organized by the Boston University (BU) Superfund Research Program (SRP) Center.
PFAS chemicals have received increasing attention because they have been found in several drinking water systems and have been linked to reproductive, developmental, liver, kidney, and immunological effects.
In a December 2016 CHE call, presenters outlined the problem of PFAS in drinking water. Because of continued interest in the topic and the high volume of emerging research, organizers held this follow-up webinar to delve into practical information about PFAS testing and interpretation of contamination data, as well as new findings on potential health effects. Speakers included BU SRP Center grantee Tom Webster, D.Sc.; Nancy Rothman, Ph.D., CEO and Principal Scientist of New Environmental Horizon, Inc.; and Richard Spiese, of the Vermont Department of Environmental Conservation, Waste Management Division.
Talks by Rothman and Spiese focused on the latest methods for measuring PFAS in drinking water and how PFAS contamination in drinking water is being addressed.
"The field of expertise is expanding quickly, and there are a lot of resources to help you keep informed on changes to regulations and methods for testing," said Rothman. She emphasized the importance of using labs with experience in PFAS analysis and described the data needed to accurately measure PFAS in community drinking water.
Spiese described lessons learned on installing and operating systems to remove PFAS at impacted residences in Vermont. He discussed system installation and their process for inspection, maintenance, and long-term monitoring of PFAS concentrations.
Webster followed the first two talks with the current state of the science on the health effects of PFAS exposure.
"We have seen an explosion of research on PFAS since the last call in December 2016," Webster said. "Since then, about 40 PFAS epidemiology papers have been published linking PFAS to health outcomes." These studies have reported associations between increased PFAS exposure and higher risk of preterm birth, thyroid hormone disruption, and decreased visual motor ability.
The webinar was moderated by BU SRP Research Translation Core leader Wendy Heiger-Bernays, Ph.D. In her introduction, she provided a short overview of the SRP and encouraged participants to learn more about the University of Rhode Island SRP Center, which is focused on sources, transport, exposure, and effects of PFAS.
EPA Adds Six Hazardous Waste Sites to the National Priorities List
The U.S. Environmental Protection Agency (EPA) recently announced that it added six hazardous waste sites to the National Priorities List (NPL) of Superfund sites. In addition, EPA is proposing to add four additional sites to the list.
The added sites in Delaware, Indiana, Minnesota, South Carolina, and Texas include former textile manufacturing sites, former metal finishing and electroplating sites, and groundwater plumes.
Superfund is the federal program that investigates and cleans up complex, uncontrolled, or abandoned hazardous waste sites in the country. Proposed and newly added NPL sites may offer opportunities for SRP grantees to conduct research.
SRP Brings Solution-Oriented Science to SOT
Superfund Research Program (SRP) grantees from all over the country gathered in San Antonio, Texas, for the 2018 Society of Toxicology (SOT) Annual Meeting March 11 – 15. Grantees and staff gave talks and presented posters highlighting SRP-funded research advances in toxicology.
More than 80 SRP project leaders and trainees from at least 13 SRP Centers presented oral or poster presentations. NIEHS SRP staff members Danielle Carlin, Ph.D., Michelle Heacock, Ph.D., Heather Henry, Ph.D., Brittany Trottier, and SRP Director Bill Suk, Ph.D., were on hand to meet with grantees, view their posters, and discuss their innovative research. An SRP reception also gave trainees the opportunity to network.
Some SRP grantees chaired sessions exploring cutting-edge toxicology research. Texas A&M University SRP Center Director Ivan Rusyn, Ph.D., co-chaired a workshop focused on reducing uncertainty when predicting the toxicity of a chemical based on data from similar chemicals. University of North Carolina at Chapel Hill SRP Center Director Rebecca Fry, Ph.D., co-chaired a symposium on the role of epigenetic changes on metal-induced diseases. Epigenetic changes affect the function of genes without changing the underlying DNA sequence.
Carlin also co-chaired a symposium titled, "Atherosclerosis as a Model to Understand the Combined Effects of Environmental Chemical and Non-Chemical Stressors." Presentations covered how chemical and non-chemical stressors may lead to atherosclerosis, biological mechanisms of environmentally relevant chemicals, how diet and physical activity may modify atherosclerotic events, and how conceptual models can be created to evaluate complex pathways in this disease. The session included presentations by University of Kentucky SRP Center Director Bernhard Hennig, Ph.D., and University of Louisville SRP Center Director Sanjay Srivastava, Ph.D.
SRP staff were also available in the NIEHS Research Funding Insights Room, where current grantees and applicants could speak with program officers or scientific review officers about the grants process. In a special session on federal research funding opportunities, Heacock presented an NIH grants overview. Following her presentation, former Boston University SRP Center grantee and current NIEHS Outstanding New Environmental Science awardee Neel Aluru, Ph.D., described keys to success and lessons learned in the NIH grants process.
For more information about NIEHS at SOT, see the Environmental Factor article.
Additional SOT photos of SRP grantees are presented below, courtesy of Heather Henry:
SRP Grantee Presents NIEHS Seminar on Clinical Intervention for Pain
Renowned scientist and Superfund Research Program (SRP) grantee Bruce Hammock, Ph.D., was invited to present the Immunity, Inflammation, and Disease Laboratory Special Seminar at NIEHS on March 28, 2018. Hammock's talk focused on neuropathic pain, which is caused by damage or disease affecting the body's sensory system, and how findings from his lab are being translated into clinical interventions.
"We currently lack medical tools to address neuropathic pain, and there hasn't been a great deal of interest or ability to come up with new drugs among pharmaceutical companies," Hammock said. "This leaves a critical need for options to treat this pain and improve quality of life for patients suffering from a wide variety of common diseases."
Hammock, who has led the University of California (UC) Davis SRP Center since its inception in 1987, is best known for his discovery of soluble epoxide hydrolase (sEH), an enzyme in cells that degrades chemically stable fatty acid epoxides. He described how blocking the function of this enzyme can reduce endoplasmic reticulum (ER) stress, which is an underlying mechanism by which many diseases produce inflammation and pain.
According to Hammock, blocking sEH function — and therefore ER stress — may be a way to treat neuropathic and inflammatory pain, as well as other diseases stemming from ER stress, such as asthma, fibrosis, diabetic neuropathy, colitis, and depression.
Trainee Research Featured in the SRP Poster Winners Webinar
On March 27, 2018, the four winners from the Superfund Research Program (SRP) Annual Meeting's poster competition presented their outstanding research via webinar to an interdisciplinary audience of SRP staff and grantees.
In his opening remarks, SRP Director Bill Suk, Ph.D., said: "The SRP is a firm supporter of training in the broadest possible way within our multidisciplinary framework. I'm really looking forward to hearing from these four outstanding trainees and for this opportunity for them to share their research with all of you."
The webinar provided a great opportunity for people who were not able to view the student posters at the SRP Annual Meeting to hear the winners describe their current research and future directions:
- Stephanie Kim of Boston University described her use of digital gene expression profiling to understand how metabolism-disrupting chemicals alter the characteristics of fat cells.
- The University of Kentucky's Hongyi (Derek) Wan shared how he has developed membrane platforms with iron and palladium nanoparticles to remove polychlorinated biphenyls from water.
- Kelly Fader of Michigan State University talked about how dioxin exposure increases bone mass and decreases fat cells in bone marrow while also disrupting bone resorption.
- Texas A&M University's Meichen Wang discussed her research to develop a broad-acting sorbent that could be used as a dietary supplement to bind to harmful chemicals in the intestine, preventing their absorption in the body and protecting human health.
Eight Northeast SRP Centers Convene at Regional Meeting
The Northeast Superfund Research Program (SRP) Meeting brought together eight SRP Centers to discuss collaborations and network. Held in Woods Hole, Massachusetts, on March 26 – 27, the meeting included scientific presentations and poster sessions.
Grantees discussed wide-ranging topics, including the exposome, big data, fate and transport of contaminants, remediation approaches, and community engagement. The meeting also had a special focus on trainee development and included a poster competition, speed mentoring, and networking events.
SRP Health Scientist Administrator Michelle Heacock, Ph.D., was on hand to meet with grantees and hear about their exciting research. "The Northeast SRP Meeting was a unique opportunity for these Centers to come together and discuss their diverse research in a shared regional context," she noted.
The Boston University, Brown University, Columbia University, Dartmouth College, Massachusetts Institute of Technology, Northeastern University, University of Pennsylvania, and University of Rhode Island SRP Centers participated in the meeting.
Workshop Takes Next Steps with Lancet Commission Report
Environmental health experts gathered March 1 - 2, 2018, in Seattle, Washington, to create a strategic framework for addressing global pollution using the 2017 Lancet Commission on Pollution and Health report. The workshop was convened by the Global Burden of Disease (GBD) project's Pollution and Health Initiative.
Several current and previous Superfund Research Program (SRP) grantees attended the workshop, including Philippe Grandjean, Ph.D., from the University of Rhode Island SRP Center; Philip Landrigan, M.D., from the Ichan School of Medicine at Mount Sinai; Howard Hu, M.D., from the University of Toronto; and David Bellinger, Ph.D., from Harvard University. Landrigan, one of 40 international authors of the Lancet Commission report, discussed plans to establish a Global Pollution Observatory that will collect and curate data on pollution and pollution-related disease to share with the scientific community.
According to the report, 16 percent of all deaths worldwide can be directly linked to pollution, such as air pollution, lead, neurodevelopmental toxicants, and climate change. The economic costs associated with pollution were estimated at more than $4.6 trillion per year.
"We realized that it was important to document not only the health impacts of global pollution, but also the measurable costs of pollution as an economic burden," said SRP Director Bill Suk, Ph.D., an author on the report. "This is the first analysis to comprehensively report both aspects."
The GBD workshop and related efforts are exploring ways to enhance data collection, improve communication with decision-makers, and reduce pollution to decrease the burden of disease and associated economic costs around the world.
Iowa SRP Center Model Enables Accurate Air Pollutant Measurements
The University of Iowa Superfund Research Program (SRP) released a Web-based application to help researchers and regulators more accurately determine pollutant concentrations in air using passive air samplers. The application is designed to predict the sampling rates and volumes captured by passive air samplers equipped with polyurethane foam (PUF-PAS), which are frequently used to capture and measure airborne persistent organic pollutants (POPs).
The Web-based application helps users understand how much air went through a PUF-PAS sampler, which is needed to predict the airborne POP concentration. It uses a mathematical model based on user-entered deployment dates of the passive sampler and the compounds of interest. The model uses publicly available hourly meteorological data and the physical and chemical properties of the target compounds to predict the sampling rate and sampling volume for gas-phase compounds captured by the sampler. It can be used to accurately predict the sampling volume of passive air samplers deployed anywhere in the world.
This interface was developed based on research described in an Iowa SRP Center publication led by Keri Hornbuckle, Ph.D. In a 2017 Risk e-Learning webinar, Hornbuckle described this work, as well as other methods for accurate and reproducible measurements of polychlorinated biphenyls (PCBs), a type of POP, in air, water, soil, sediment, pore water, plant tissue, and human blood serum.
SRP Researchers Create Ultrastretchable Nano Barrier for Numerous Applications
Novel textured coatings made from graphene can act as ultrastretchable barriers to stop chemicals and other molecules from passing through, according to new research from the Brown University Superfund Research Program Center. The authors suggest these novel films could be used to create multifunctional fabrics and responsive devices, including personal monitoring equipment, wearable electronics, and soft robotics.
The research team used graphene nano-sheets that can change shape by folding and unfolding to mimic a more elastic behavior, which improves upon traditional approaches that create a material that is quite stiff and cracks easily. The stretchable technology also can function as a sensor to detect certain chemicals and to act as either an impassible or selective barrier. These characteristics will make the material useful for a variety of future cutting-edge applications.
SRP Grantees Work to Improve Water Quality for Native Communities
Researchers at the University of New Mexico's Superfund Research Program Center (UNM SRP Center) are studying the effects of exposure to uranium and mixed metals mining waste in water on Native Americans in the southwest. Funded in the fall of 2017, their work is already making headlines. Center Director Johnnye Lewis, Ph.D., was recently featured in the UNM College of Pharmacy's Lobo Script monthly magazine and in the Albuquerque Journal.
Lewis described how UNM SRP Center researchers are investigating the health impacts of mixed metals and uranium exposures on Native Americans, how these contaminants move through the environment, and how they can be stabilized to decrease their movement into surface water and to protect human health.
Lewis explained that an estimated 40 percent of surface water in the western U.S. is contaminated with uranium, and tribes in these regions rely much more heavily on surface water than do other populations for not only drinking but also for irrigation, livestock watering, and cultural uses.
Lewis is also part of a collaboration aiming to reach the World Health Organization's goal of providing clean drinking water to all people by 2030. Organized by the United Nations Children's Fund, the Global Water Challenge, Stanford University's Water in the West program, and the U.S. Water Partnership, the collaborative is identifying barriers and developing a roadmap to ensure the U.S. meets the 2030 goal. Lewis' work in this collaborative is focused on providing clean drinking water for Native Americans and others in the southwest, where infrastructure is deteriorating and unaffordable for many communities.
SRP Grantees Participate in Federal PFAS Information Exchange
On February 5 - 6, Superfund Research Program (SRP) grantees provided their expertise and perspectives during the Federal Information Exchange on per- and polyfluoroalkyl substances (PFAS) in Bethesda, Maryland. PFAS chemicals have received increasing attention because they have been found in several drinking water systems and have been linked to reproductive, developmental, liver, kidney, and immunological effects.
Hosted by the Toxics and Risks Subcommittee of the National Science and Technology Council, the workshop provided a forum to share emerging data and key knowledge gaps in the sources, pathways, treatment, and health effects of PFAS. SRP grantees Raymond Ball, Ph.D., Jennifer Guelfo, Ph.D., and Angela Slitt, Ph.D., participated in the workshop.
"The meeting was informative and underlined the magnitude of the PFAS problem," said Ball, president and principal engineer at the NIEHS-funded small business EnChem Engineering. As part of his SRP project, Ball's team is developing a technology to expedite the removal of PFAS from soil and groundwater.
The meeting opened with remarks from senior government officials, including NIEHS Director Linda Birnbaum, Ph.D., and the Centers for Disease Control and Prevention's National Center for Environmental Health Director Patrick Breysse, Ph.D. Following talks from researchers about new findings in their areas of expertise, federal employees and federally funded researchers participated in breakout sessions to discuss current scientific knowledge and future directions.
"The meeting provided a platform for researchers and employees across federal agencies to hear how each is engaged in science and decision-making regarding PFAS," said Guelfo, a researcher at the Brown University SRP Center. Her recent work has focused on using publicly available data to develop models that predict areas with potential PFAS groundwater contamination.
"Given that PFAS includes thousands of compounds, one recurring theme was the need for methods for prioritizing compounds and the need to understand the influence of mixtures," Guelfo added. "There was also a lot of discussion about developing standard methods for PFAS analysis."
In addition to discussions about routes of exposure and treatment methods, time was set aside to discuss the current understanding of the health effects of PFAS. Slitt, a grantee at the University of Rhode Island SRP Center, is studying whether PFAS exposure increases the risk for obesity-induced fatty liver disease and metabolic disorders.
In the final session, participants discussed risk assessment, consideration of data needs for protecting human health, and ongoing coordination and communication across federal agencies. The workshop was immediately followed by a closed Toxics and Risks Subcommittee meeting to discuss how these findings will inform agencies moving forward.
Improving Site Characterization to Assess Contaminant Removal
A computational model can be used to measure how different factors influence the removal of groundwater contaminants at hazardous waste sites, according to a study from the University of Arizona Superfund Research Program Center. Researchers led by Mark Brusseau, Ph.D., developed the predictive model and found that their contaminant estimates from the model compared well to measurements taken at a Superfund site.
Their model uses the relationship between reductions in contaminant discharge and removal as the metric to examine remediation efficiency. Characterization methods such as this may help researchers more easily understand factors that may impact the distribution of contaminants at a site, which can provide more information about the effectiveness of remediation efforts.
Building on these findings, the research team used the model to examine factors that influence contaminant removal in large groundwater contaminant plumes. Specifically, they looked at areas with low groundwater flow adjacent to large aquifer systems, which is common at many hazardous waste sites.
They found that the location of pump-and-treat wells, relative to contaminated water, can have a significant impact on how effectively contaminants are removed and how they persist in large groundwater systems. Based on well configuration, zones may be formed where contaminants remain stagnant, which reduces the effectiveness of pump and treat. This illustrates the need for dynamic system operations in which the system is routinely monitored and operational conditions are modified to maintain peak performance.
In a 2017 Risk e-Learning webinar, Brusseau described this work, as well as other efforts to improve characterization methods to understand the factors contributing to the persistence of contaminants in groundwater.
SRP Research Finds Ancestry-Based Differences in Telomere Length Genes
People with different ancestries may inherit telomere length differently, according to a new study from the Columbia University Superfund Research Program (SRP) Center. Telomeres are segments at the end of DNA, and telomere length plays an important role in aging and aging-related diseases. This study provides new information about the genes associated with telomere length across populations and highlights the importance of including diverse populations in genome-wide association studies (GWAS).
Although telomere length is a heritable trait, it still can vary considerably between individuals and populations, leading scientists to study how it is passed between generations. Previous studies that have investigated how telomere length is inherited have relied primarily on populations of European descent. In this study, researchers used samples from the Health Effects of Arsenic Longitudinal Study cohort in Bangladesh and found important ancestry-based differences in how telomere length might be passed on.
In addition to replicating some findings from other genome-wide association studies, such as those showing that gene regions called TERT and TERC are related to telomere length, the researchers also identified a new association. The study reports a link between telomere length and a gene region called RTEL1 and, importantly, a distinct second region of RTEL1 that had not been previously identified in relation to telomere length. This specific region of RTEL1 is common in South Asian populations but less so in other populations.
SRP Grantee Featured in Science Friday Video
Karletta Chief, Ph.D., of the University of Arizona Superfund Research Program (SRP) Center was recently interviewed on Science Friday. Her interview coincided with the release of the sixth and final installment of a short video anthology, "Breakthrough: Portraits of Women in Science," which follows women working at the forefront of their fields.
Bitter Water, the last film in the anthology, featured Chief and her SRP-funded work to address the concerns of the Navajo community after the Gold King Mine spill in 2015. In both the video and the interview, Chief explained how her research team helped identify more than 100 unique cultural uses of the river that were not previously considered in exposure estimates. They also studied how metals and other potentially toxic contaminants moved through the river’s sediment and water. Chief further shared her personal history and experiences leading her to become a hydrologist.
The Breakthrough anthology from Science Friday and the Howard Hughes Medical Institute blends the personal stories of women in science, technology, engineering, and math with highlights of their innovative scientific research and accomplishments.
Fish Adaptation to TCDD Seen at the Genome Level
Long-term exposure to environmental toxicants can affect the genome of Hudson River tomcod much more than previously expected, according to researchers led by Isaac Wirgin, Ph.D., at the New York University School of Medicine. A recent study led by Isaac Wirgin, Ph.D. and his team sheds light on the effects of exposure to the pollutant 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) on the genomes, or full set of genes, from two tomcod populations 86 miles apart with distinctly different exposure histories.
The recent findings build on Wirgin’s Superfund Research Program (SRP)-funded work. The Hudson River Estuary in the New York City Metropolitan area has a long history of pollutants from both local and distant sources. In a study in the journal Science in 2011, funded in part by the SRP, Wirgin and his team describe how Atlantic tomcod in the Hudson River have genetically evolved to withstand the effects of pollutants, primarily polychlorinated biphenyls (PCBs), in the river.
In the new study, the researchers used larvae from both the pollutant-resistant Hudson River tomcod population and a non-resistant nearby Shinnecock Bay population. They exposed the two groups of larvae to TCDD and then compared the global expression of genes in the resistant and non-resistant tomcod.
They observed differences between the two populations in the number of genes that were expressed differently at all doses of TCDD. At the two lowest TCDD doses, 250 and 1,141 genes were differentially expressed in Shinnecock Bay larvae compared with only 14 and 12, respectively, in Hudson River larvae. At the highest dose, 934 genes were differentially expressed in Shinnecock Bay larvae and 173 in Hudson River larvae, but only 16 percent of affected genes were shared among both populations.
“I think the data is pretty dramatic in demonstrating just how great the effect of Hudson River-borne pollutants has been on the evolution of its tomcod population,” said Wirgin. “Pollutants can have far greater effects on exposed populations than we ever imagined.”
According to the authors, understanding differences in gene expression will allow them to better understand the toxic impacts of exposure and evaluate their mechanistic basis.
SRP Grantee Takes Cleanup Technology to the Field
Superfund Research Program (SRP) grantee Dibakar Bhattacharyya, Ph.D., of the University of Kentucky was recently awarded funding to help the Chevron Corporation remove metals and other potentially harmful contaminants from wastewater created during oil production.
Bhattacharyya's SRP-funded work was critical in laying the foundation that provided the opportunity to transfer his technology from the laboratory to the field. His team at the University of Kentucky SRP Center pioneered the development and use of specialized membranes to break down toxic organic compounds, such as polychlorinated biphenyls, trichloroethylene, and napthenic acids in water.
These membranes, which are embedded with nanoparticles in the lab, also can be used to capture metals like arsenic and mercury, making them ideal for the work with Chevron.