Superfund Research Program
Blocking Mosquitoes with a Graphene Shield
An innovative graphene-based film helps shield people from disease-carrying mosquitoes, according to a new study. The research, conducted by the Brown University Superfund Research Program (SRP) Center, was published August 26 in the Proceedings of the National Academy of Sciences.
“These findings could lead to new protective methods against mosquitoes, without the environmental or human health effects of other chemical-based repellants,” said Heather Henry, Ph.D., a health scientist administrator with the NIEHS SRP.
The study, led by Brown SRP Center Director Robert Hurt, Ph.D., shows that graphene, a tight, honeycomb lattice of carbon, could be an alternative to chemicals now used in mosquito repellants and protective clothing.
Through an SRP research project, Hurt fabricates and tests high-performance, graphene-based environmental barriers to prevent the release and transport of vapor toxicants. Several years ago, he began devising suits with graphene to protect workers against hazardous chemicals at environmental cleanup sites. Hurt and his team also started looking into other applications for the effective barrier.
In the new study, researchers found dry graphene film seemed to interfere with mosquitoes’ ability to sense skin and sweat because they did not land and try to bite. A closer look at videos taken of the mosquitoes in action revealed that the insects landed much less frequently on graphene than on bare skin. The graphene film also provided a strong barrier that mosquitoes could not bite through, although when wet with sweat, mosquitoes landed on skin.
NIEHS SRP Director Bill Suk, Ph.D., was pleased to see that this new use for graphene was developed as an offshoot of his program’s work. “SRP is a problem-solving program,” said Suk. “This is a significant public health problem that is in need of a solution."
To read more about this work, see the September 2019 issue of the NIEHS Environmental Factor.
SRP Presented New Research at PFAS Meeting
Superfund Research Program (SRP) grantees from around the country gathered August 12 – 15 to discuss per- and polyfluoroalkyl substances (PFAS) at the Society of Environmental Toxicology and Chemistry's North America Focused Topic Meeting in Durham, North Carolina.
Several SRP trainees presented posters on their research, including Anna Robuck and Jitka Becanova, Ph.D., of the University of Rhode Island (URI) Sources, Transport, Exposure, and Effects of PFAS (STEEP) SRP Center. Robuck's poster described her work to characterize PFAS profiles in seabirds to better understand how and which PFAS are accumulating in wildlife. Becanova described the development of passive samplers, designed with the unique capability of detecting PFAS in both air and water.
During the poster session, SRP Health Scientist Administrators Michelle Heacock, Ph.D., and Heather Henry, Ph.D., promoted new tools and technologies the program's researchers are developing to characterize PFAS in the environment and to remove PFAS from water, soil, and sediment. They also featured work from SRP grantees who are examining how PFAS may harm human health. Finally, they highlighted activities wherein SRP-funded centers are sharing research findings and information on PFAS to communities that may be affected by PFAS exposure.
Jennifer Guelfo, Ph.D., of Texas Tech University and the Brown University SRP Center, presented her research and discussed the challenges of characterizing the vast number of different PFAS compounds. She is working to discern how to prioritize PFAS based on sources and pathways of exposure. Along a similar line of inquiry, Elsie Sunderland, Ph.D., of Harvard University and the URI STEEP SRP Center, chaired a session on exposure assessment for PFAS. Understanding where PFAS are found in the environment is the first step in understanding how people and animals encounter them. This information, in turn, helps researchers conduct risk assessments and determine ways to protect health.
Modifying Microbes to Reduce Soil Contamination
Microbes in soil can break down just about anything from fallen leaves to harmful contaminants, with the right combination of species. The Duke University Superfund Research Program (SRP) Center identifies which microbial communities in soils can enhance degradation of contaminants.
The Duke researchers recently characterized microbes that can break down creosote in soil. Creosote is a type of polycyclic aromatic hydrocarbon (PAH), a large group of hazardous chemicals commonly found at Superfund sites.
Using gene sequencing, the researchers found three types of microbes, Geobacter, Mycobacterium, and Sphingomonads, that could survive in creosote-contaminated soil and break down PAHs and other contaminants.
Characterizing microbes and their ability to break down contaminants is the first step in identifying ways to enhance bioremediation at PAH-contaminated sites. As scientists acquire more genetic data on bacteria, they aim to expand their database of microbes that can withstand and degrade PAHs, which contains information for improving bioremediation processes.