Superfund Research Program
Suk Receives Fulbright Award to Support Environmental Health in Thailand
Superfund Research Program (SRP) Director William A. Suk, Ph.D., M.P.H., has been selected to receive a prestigious Fulbright U.S. Scholar Program award to increase environmental health capacity in South and Southeast Asia. As part of the international educational exchange program, Suk will serve as Fulbright lecturer in international and public health in collaboration with Mahidol University and the Chulabhorn Research Institute in Bangkok, Thailand.
During his six-month Fulbright, Suk will teach courses and aid in program development for universities in Thailand and surrounding countries, with an emphasis on children’s environmental health and early-life exposures that lead to disease. He also will address global health concerns, such as chronic kidney disease of unknown origin (CKDu) and potentially harmful exposures from electronic waste, and will promote the development of tools and technologies to reduce exposures.
Suk will meet with researchers, postdocs, students, pediatricians, environmental health scientists, public health workers, and governmental ministries in South and Southeast Asia to discuss how environmental exposures may lead to disease and the importance of developing ways to intervene and prevent these diseases. He also will promote the SRP as a model for other universities to develop similar multidisciplinary research and training programs.
The Fulbright Program is sponsored by the U.S. government and is designed to build lasting connections between the people of the U.S. and those of other countries. Recipients of Fulbright awards are selected based on their academic and professional achievements, as well as record of service and demonstrated leadership in their respective fields.
Method Predicts Bioavailability of Mercury in Water and Sediment
In a new Superfund Research Program (SRP) study, researchers show how a simple sampler can be used to estimate mercury bioavailability – the amount of mercury that can be taken up by organisms – in sediment and water.
In mercury-contaminated sediment and water, bacteria can convert mercury into methylmercury, its more toxic and more bioavailable form. Because of this process, the bioavailability of mercury to these microbes and the production of methylmercury by bacteria are critical steps toward bioaccumulation of methylmercury in fish.
To better predict mercury bioavailability at a contaminated site, researchers led by Duke University scientist Heileen Hsu-Kim, Ph.D., investigated how different types of samplers can be used to measure the amount of mercury that is bioavailable in the environment. They compared several detection methods and found that sampling devices placed in water or sediment to detect a variety of metals, called diffusive gradient in thin-film passive samplers (DGT passive samplers), were the best predictor of mercury bioavailability. They found that the net production of methylmercury correlated well with the accumulation of mercury on the DGT passive samplers.
The study was supported by an SRP individual project grant focused on evaluating mercury methylation potential during remediation of contaminated sediments. According to the authors, this method has the potential to help researchers and site managers improve their understanding of the factors controlling mercury methylation at field sites. This could help them to predict how changes at the site, such as remediation efforts, might alter methylmercury production.
Dartmouth Superfund Research Program Informs International Mercury Reduction Efforts
A recent article highlights key research advances and needs to inform international policy decision making related to mercury. The article, co-authored by Celia Chen, Ph.D., of the Dartmouth College Superfund Research Program (SRP) Center, emphasizes the importance of bringing together scientific information to better understand the sources of mercury, its movement through the environment, and its effects on human and ecosystem health. Chen is an internationally recognized researcher on the accumulation of metals like mercury in aquatic food webs and serves as director of the Dartmouth SRP’s Research Translation Core.
Mercury contamination is a global problem. Recent advances in the measurement of mercury have helped scientists identify and monitor mercury in the environment. They have found that mercury levels in the atmosphere have been going down in North America and Europe; however, these levels have been increasing in East Asia and the Southern Hemisphere. More research is needed to understand mercury use and transport at the global scale.
This understanding is important as mercury can have adverse effects in humans, such as nervous system and digestive system toxicity. Symptoms can include memory loss, tremors, insomnia, and cognitive and motor dysfunction. Humans can be exposed to mercury through eating fish that contain a toxic form of mercury called methylmercury. Chen and other researchers are learning how mercury in the environment becomes available to organisms like fish and transforms into methylmercury. They also are developing effective ways to educate communities that rely on fish for their diet.
More research is also needed to understand how climate change might influence mercury movement through the environment. For example, during wildfires, mercury that was absorbed into plants can be released into the environment again. With predictions of more wildfires and other factors related to climate change, scientists are researching these processes to help policymakers with science-based decision making and land-use planning.
The recent paper is based on important findings and next steps discussed at the SRP-sponsored 13th International Conference on Mercury as a Global Pollutant (ICMGP-13), held in Providence, Rhode Island, in July 2017. A major goal of the conference was to inform policy changes in support of the Minamata Convention, which aims to protect human health and the environment from mercury releases. ICMGP-13 organizers previously commissioned four papers, published in the journal Ambio, to communicate important information from the conference.