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    Smarter regulation of global shipping emissions could improve air quality and health outcomes

    Emissions from shipping activities around the world account for nearly 3 percent of total human-caused greenhouse gas emissions, and could increase by up to 50 percent by 2050, making them an important and often overlooked target for global climate mitigation. At the same time, shipping-related emissions of additional pollutants, particularly nitrogen and sulfur oxides, pose a significant threat to global health, as they degrade air quality enough to cause premature deaths.

    The main source of shipping emissions is the combustion of heavy fuel oil in large diesel engines, which disperses pollutants into the air over coastal areas. The nitrogen and sulfur oxides emitted from these engines contribute to the formation of PM2.5, airborne particulates with diameters of up to 2.5 micrometers that are linked to respiratory and cardiovascular diseases. Previous studies have estimated that PM2.5  from shipping emissions contribute to about 60,000 cardiopulmonary and lung cancer deaths each year, and that IMO 2020, an international policy that caps engine fuel sulfur content at 0.5 percent, could reduce PM2.5 concentrations enough to lower annual premature mortality by 34 percent.

    Global shipping emissions arise from both domestic (between ports in the same country) and international (between ports of different countries) shipping activities, and are governed by national and international policies, respectively. Consequently, effective mitigation of the air quality and health impacts of global shipping emissions will require that policymakers quantify the relative contributions of domestic and international shipping activities to these adverse impacts in an integrated global analysis.

    A new study in the journal Environmental Research Letters provides that kind of analysis for the first time. To that end, the study’s co-authors — researchers from MIT and the Hong Kong University of Science and Technology — implement a three-step process. First, they create global shipping emission inventories for domestic and international vessels based on ship activity records of the year 2015 from the Automatic Identification System (AIS). Second, they apply an atmospheric chemistry and transport model to this data to calculate PM2.5 concentrations generated by that year’s domestic and international shipping activities. Finally, they apply a model that estimates mortalities attributable to these pollutant concentrations.

    The researchers find that approximately 94,000 premature deaths were associated with PM2.5 exposure due to maritime shipping in 2015 — 83 percent international and 17 percent domestic. While international shipping accounted for the vast majority of the global health impact, some regions experienced significant health burdens from domestic shipping operations. This is especially true in East Asia: In China, 44 percent of shipping-related premature deaths were attributable to domestic shipping activities.

    “By comparing the health impacts from international and domestic shipping at the global level, our study could help inform decision-makers’ efforts to coordinate shipping emissions policies across multiple scales, and thereby reduce the air quality and health impacts of these emissions more effectively,” says Yiqi Zhang, a researcher at the Hong Kong University of Science and Technology who led the study as a visiting student supported by the MIT Joint Program on the Science and Policy of Global Change.

    In addition to estimating the air-quality and health impacts of domestic and international shipping, the researchers evaluate potential health outcomes under different shipping emissions-control policies that are either currently in effect or likely to be implemented in different regions in the near future.

    They estimate about 30,000 avoided deaths per year under a scenario consistent with IMO 2020, an international regulation limiting the sulfur content in shipping fuel oil to 0.5 percent — a finding that tracks with previous studies. Further strengthening regulations on sulfur content would yield only slight improvement; limiting sulfur content to 0.1 percent reduces annual shipping-attributable PM2.5-related premature deaths by an additional 5,000. In contrast, regulating nitrogen oxides instead, involving a Tier III NOx Standard would produce far greater benefits than a 0.1-percent sulfur cap, with 33,000 further avoided deaths.

    “Areas with high proportions of mortalities contributed by domestic shipping could effectively use domestic regulations to implement controls,” says study co-author Noelle Selin, a professor at MIT’s Institute for Data, Systems and Society and Department of Earth, Atmospheric and Planetary Sciences, and a faculty affiliate of the MIT Joint Program. “For other regions where much damage comes from international vessels, further international cooperation is required to mitigate impacts.” More

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    Using graphene foam to filter toxins from drinking water

    Some kinds of water pollution, such as algal blooms and plastics that foul rivers, lakes, and marine environments, lie in plain sight. But other contaminants are not so readily apparent, which makes their impact potentially more dangerous. Among these invisible substances is uranium. Leaching into water resources from mining operations, nuclear waste sites, or from natural subterranean deposits, the element can now be found flowing out of taps worldwide.

    In the United States alone, “many areas are affected by uranium contamination, including the High Plains and Central Valley aquifers, which supply drinking water to 6 million people,” says Ahmed Sami Helal, a postdoc in the Department of Nuclear Science and Engineering. This contamination poses a near and present danger. “Even small concentrations are bad for human health,” says Ju Li, the Battelle Energy Alliance Professor of Nuclear Science and Engineering and professor of materials science and engineering.

    Now, a team led by Li has devised a highly efficient method for removing uranium from drinking water. Applying an electric charge to graphene oxide foam, the researchers can capture uranium in solution, which precipitates out as a condensed solid crystal. The foam may be reused up to seven times without losing its electrochemical properties. “Within hours, our process can purify a large quantity of drinking water below the EPA limit for uranium,” says Li.

    A paper describing this work was published in this week Advanced Materials. The two first co-authors are Helal and Chao Wang, a postdoc at MIT during the study, who is now with the School of Materials Science and Engineering at Tongji University, Shanghai. Researchers from Argonne National Laboratory, Taiwan’s National Chiao Tung University, and the University of Tokyo also participated in the research. The Defense Threat Reduction Agency (U.S. Department of Defense) funded later stages of this work.

    Targeting the contaminant

    The project, launched three years ago, began as an effort to find better approaches to environmental cleanup of heavy metals from mining sites. To date, remediation methods for such metals as chromium, cadmium, arsenic, lead, mercury, radium, and uranium have proven limited and expensive. “These techniques are highly sensitive to organics in water, and are poor at separating out the heavy metal contaminants,” explains Helal. “So they involve long operation times, high capital costs, and at the end of extraction, generate more toxic sludge.”

    To the team, uranium seemed a particularly attractive target. Field testing from the U.S. Geological Service and the Environmental Protection Agency (EPA) has revealed unhealthy levels of uranium moving into reservoirs and aquifers from natural rock sources in the northeastern United States, from ponds and pits storing old nuclear weapons and fuel in places like Hanford, Washington, and from mining activities located in many western states. This kind of contamination is prevalent in many other nations as well. An alarming number of these sites show uranium concentrations close to or above the EPA’s recommended ceiling of 30 parts per billion (ppb) — a level linked to kidney damage, cancer risk, and neurobehavioral changes in humans.

    The critical challenge lay in finding a practical remediation process exclusively sensitive to uranium, capable of extracting it from solution without producing toxic residues. And while earlier research showed that electrically charged carbon fiber could filter uranium from water, the results were partial and imprecise.

    Wang managed to crack these problems — based on her investigation of the behavior of graphene foam used for lithium-sulfur batteries. “The physical performance of this foam was unique because of its ability to attract certain chemical species to its surface,” she says. “I thought the ligands in graphene foam would work well with uranium.”

    Simple, efficient, and clean

    The team set to work transforming graphene foam into the equivalent of a uranium magnet. They learned that by sending an electric charge through the foam, splitting water and releasing hydrogen, they could increase the local pH and induce a chemical change that pulled uranium ions out of solution. The researchers found that the uranium would graft itself onto the foam’s surface, where it formed a never-before-seen crystalline uranium hydroxide. On reversal of the electric charge, the mineral, which resembles fish scales, slipped easily off the foam.

    It took hundreds of tries to get the chemical composition and electrolysis just right. “We kept changing the functional chemical groups to get them to work correctly,” says Helal. “And the foam was initially quite fragile, tending to break into pieces, so we needed to make it stronger and more durable,” says Wang.

    This uranium filtration process is simple, efficient, and clean, according to Li: “Each time it’s used, our foam can capture four times its own weight of uranium, and we can achieve an extraction capacity of 4,000 mg per gram, which is a major improvement over other methods,” he says. “We’ve also made a major breakthrough in reusability, because the foam can go through seven cycles without losing its extraction efficiency.” The graphene foam functions as well in seawater, where it reduces uranium concentrations from 3 parts per million to 19.9 ppb, showing that other ions in the brine do not interfere with filtration.

    The team believes its low-cost, effective device could become a new kind of home water filter, fitting on faucets like those of commercial brands. “Some of these filters already have activated carbon, so maybe we could modify these, add low-voltage electricity to filter uranium,” says Li.

    “The uranium extraction this device achieves is very impressive when compared to existing methods,” says Ho Jin Ryu, associate professor of nuclear and quantum engineering at the Korea Advanced Institute of Science and Technology. Ryu, who was not involved in the research, believes that the demonstration of graphene foam reusability is a “significant advance,” and that “the technology of local pH control to enhance uranium deposition will be impactful because the scientific principle can be applied more generally to heavy metal extraction from polluted water.”

    The researchers have already begun investigating broader applications of their method. “There is a science to this, so we can modify our filters to be selective for other heavy metals such as lead, mercury, and cadmium,” says Li. He notes that radium is another significant danger for locales in the United States and elsewhere that lack resources for reliable drinking water infrastructure.

    “In the future, instead of a passive water filter, we could be using a smart filter powered by clean electricity that turns on electrolytic action, which could extract multiple toxic metals, tell you when to regenerate the filter, and give you quality assurance about the water you’re drinking.” More

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    Inaugural fund supports early-stage collaborations between MIT and Jordan

    MIT International Science and Technology Initiatives (MISTI), together with the Abdul Hameed Shoman Foundation (AHSF), the cultural and social responsibility arm of the Arab Bank, recently created a new initiative to support collaboration with the Middle East. The MIT-Jordan Abdul Hameed Shoman Foundation Seed Fund is providing awardees with financial grants up to $30,000 to cover travel, meeting, and workshop expenses, including in-person visits to build cultural and scientific connections between MIT and Jordan. MISTI and AHSF recently celebrated the first round of awardees in a virtual ceremony held in Amman and the United States.

    The new grant is part of the Global Seed Funds (GSF), MISTI’s annual grant program that enables participating teams to collaborate with international peers, either at MIT or abroad, to develop and launch joint research projects. Many of the projects funded lead to additional grant awards and the development of valuable long-term relationships between international researchers and MIT faculty and students.

    Since MIT’s first major collaboration in the Middle East in the 1970s, the Institute has deepened its connection and commitment to the region, expanding to create the MIT-Arab World program. The MIT-Jordan Abdul Hameed Shoman Foundation Seed Fund enables the MIT-Arab World program to move forward on its key objectives: build critical cultural and scientific connections between MIT and the Arab world; develop a cadre of students who have a deep understanding of the Middle East; and bring tangible value to the partners in the region.

    Valentina Qussisiya, CEO of the foundation, shared the importance of collaboration between research institutes to improve and advance scientific research. She highlighted the role of AHSF in supporting science and researchers since 1982, emphasizing, “The partnership with MIT through the MISTI program is part of AHSF commitment toward this role in Jordan and hoped-for future collaborations and the impact of the fund on science in Jordan.”

    The new fund, open to both Jordanian and MIT faculty, is available to those pursuing research in the following fields: environmental engineering; water resource management; lean and modern technologies; automation; nanotechnology; entrepreneurship; nuclear engineering; materials engineering; energy and thermal engineering; biomedical engineering, prostheses, computational neuroscience, and technology; social and management sciences; urban studies and planning; science, technology, and society; innovation in education; Arabic language automation; and food security and sustainable agriculture.

    Philip S. Khoury, faculty director of MISTI’s MIT-Arab World program and Ford International Professor of History and associate provost at MIT, explained that the winning projects all deal with critical issues that will benefit both MIT and Jordan, both on- and off-campus. “Beyond the actual faculty collaboration, these projects will bring much value to the hands-on education of MIT and Jordanian students and their capacity to get to know one another as future leaders in science and technology,” he says.

    This year, the MIT-Jordan Abdul Hameed Shoman Foundation Seed Fund received numerous high-quality proposals. Applications were reviewed by MIT and Jordanian faculty and selected by a committee of MIT faculty. There were six winning projects in the inaugural round:

    Low-Cost Renewable-Powered Electrodialysis Desalination and Drip Irrigation: Amos Winter (MIT principal investigator) and Samer Talozi (international collaborator)

    iPSC and CRISPR Gene Editing to Study Rare Diseases: Ernest Fraenkel (MIT principal investigator) and Nidaa Ababneh (international collaborator)

    Use of Distributed Low-Cost Sensor Networks for Air Quality Monitoring in Amann: Jesse Kroll (MIT principal investigator) and Tareq Hussein (international collaborator)

    Radiation Effects on Medical Devices Made by 3D Printing: Ju Li (MIT principal investigator) and Belal Gharaibeh (international collaborator)

    Superprotonic Conductivity in Metal-Organic Frameworks for Proton-Exchange Membrane Fuel Cells: Mircea Dinca (MIT principal investigator) and Kyle Cordova (international collaborator)

    Mapping Urban Air Quality Using Mobile Low-cost Sensors and Geospatial Techniques: Sarah Williams (MIT principal investigator) and Khaled Hazaymeh (international collaborator)

    The goal of these funded projects is for researchers and their students to form meaningful professional partnerships across cultures and leave a lasting impact upon the scientific communities in Jordan and at MIT.

    “[The fund will] enhance the future career prospects of emerging scholars from both countries,” said awardee Professor Kyle Cordova, executive director for scientific research at Royal Scientific Society and assistant to Her Royal Highness Princess Sumaya bint El Hassan for scientific affairs. “Our young scholars will gain a unique perspective of the influence of different cultures on scientific investigation that will help them to function effectively in a multidisciplinary and multicultural environment.” More