Perspective: Overcoming Implementation Barriers for Nanotechnology in Drinking Water Treatment
Nano Impact Statement:
The unique properties that arise at the nano-scale (magnetism, high surface area, selective surface reactivity, surface catalysis, rapid ion delivery, photocatalysis, plasmonic resonance, dielectric properties, electrical conductivity, super hydrophobicity, strength, etc.) can be used to purify drinking water. While discoveries of these processes are reported in the literature, actual products and processes have been slow to mature beyond the bench-scale into larger-scale, constructed systems or consumer point of use devices for purifying drinking water. This perspective article helps identify barriers that can be overcome to enable nanotechnology for water treatment.
Recipients of National Science Foundation Graduate Research Fellowships are seen by the federal agency as potential leaders in research, teaching and innovation in engineering and science.
Career success for these students is viewed as critical to the United States maintaining its leading role in technological advancement and its strength in national security.
The NSF also counts on the students’ future contributions to boost the vitality of the country’s economy.
The Graduate Research Fellows are awarded a three-year annual stipend of $34,000 and a $12,000 cost-of-education allowance for tuition and fees to pursue graduate degrees.
They also have opportunities for internships, professional development and participation in international research projects, and the freedom to do their own research at any accredited U.S. institution of graduate education of their choice.
Three graduate students in Arizona State University’s Ira A. Fulton Schools of Engineering — each pursuing a doctoral degree — are among the 2016 recipients of the highly sought after NSF Fellowships.
See full story here: But below is the story that highlights a student in our research group:
Anjali Mulchandani graduated from the University of California, Los Angeles, in 2014 with an undergraduate degree in civil and environmental engineering. But one of things that most strongly drew her interest there was a presentation by a visiting ASU engineer.
The talk by Fulton Schools Professor Bruce Rittman, director of the Swette Center for Environmental Biotechnology, put ASU on her list of places to explore when she was ready to apply to graduate school.
On her visit she met other ASU engineering professors whose expertise aligned with her interests in water-related engineering.
Now Fulton Schools Vice Dean of Research and Innovation, Professor Paul Westerhoff, a leading water treatment researcher, is her doctoral studies advisor.
Mulchandani, who grew up in Riverside, California, says she misses the ocean beaches that are close to UCLA, “but I have fallen in love with ASU. The environmental engineering community here is great.”
Her research and studies to earn a doctoral degree in the field focus on developing ways to reduce the amount of waste generated and the amount of energy consumed by current and emerging water treatment systems.
She is getting to pursue that goal by working with the ASU team led by Westerhoff that is part of a National Science Foundation Engineering Research Center, the Nanotechnology Enabled Water Treatment Systems center, or NEWT.
She was the president of NEWT’s Student Leadership Council, heading a group of students from each of the four universities that are part of NEWT. They helped to set the direction of the center’s research agenda and to communicate to the public about the center’s work.
Those students are also forming a network to continue collaborations on research as they complete work toward their degrees and embark on their careers.
A main thrust of Mulchandani’s research is atmospheric water capture, involving “a renewable, reusable system that could collect moisture from the air, and then convert it to a liquid phase for use as drinking water,” she explains. “This kind of system could be deployed to provide water in military, disaster relief, or rural off-grid locations.”
She thought it “a humorous but apt take on my work,” when at a research meeting Professor Westerhoff described her dissertation on getting water from the air and gold from waste material as “finding valuable things in unexpected places.”
Along with research, Mulchandani is putting significant time into gaining more experience in teaching, which she also wants to be a major part of her career.
The K-12 education outreach she’s done so far has led her to “fall in love with teaching, especially with teaching young students, because they are so open to learning and get so excited about it,” she says.
Teaching is a valuable skill for scientists and engineers to learn, she adds, “because one way you truly know that you understand your research and can communicate the importance of it is when you have to explain it to a sixth-grader.”
Mulchandani has worked on a National Science Foundation-supported project with Fulton Schools Assistant Dean of Engineering Education, Associate Professor Tirupalavanam Ganesh, that teaches sixth-grade students about water-related science.
She is currently teaching an after-school program in local elementary schools for which she devised the curriculum and the experiments that her young students conduct to learn basic principles of science and engineering.
She has also recruited her fellow graduate students to participate in ASU’s annual Night of the Open Door event that showcases the university’s research endeavors.
“I’m passionate about teaching and outreach, and that’s one of the reasons I like ASU. It does a good job at fulfilling its role as a public university by trying to communicate about the research it’s doing and how it is going to benefit the public.”
Some of the lessons she teaches young students in her education outreach classes are drawn from the research Mulchandani highlighted in the proposal that earned her the NSF Graduate Research Fellowship: her work on methods to recover gold, other valuable metals and bio-oil from sewage sludge.
With her presentation titled “You flushed the toilet, now what?” she teaches students about wastewater treatment plants, metals that are in foods and personal care products that end up in sewage, how sewage and waste are currently disposed of, and new sewage treatment and resource recovery technologies.
Work in those areas not only provided her a topic for her master’s thesis but won her research presentation competitions and awards at a national Sustainable Nanotechnology Conference, at an AZ Water Association Research Workshop, and at a research symposium for ASU graduate students in civil, environmental and sustainable engineering.
She also won the AZ Water Association’s Young Professionals Fresh Ideas competition for a presentation at the AZ Water Association annual conference earlier this year. The association then sent her to the American Water Works Association Annual Conference and Exposition this past summer in Chicago, where she presented her work to a national audience of water science and engineering experts.
Getting support from an NSF Graduate Research Fellowship award to help her pursue career goals in both research and teaching is a big motivator.
The fellowship “is one of the absolute most prestigious things you can aspire to as a graduate student,” Mulchandani says, and it makes her all the more determined “to do work that solves big problems and really helps people.”
Joe Kullman, firstname.lastname@example.org
Ira A. Fulton Schools of Engineering
hromium-6, a cancer-causing chemical made famous by the legal efforts of Erin Brockovich, has been found in the drinking water of many major cities, including Phoenix. Wochit
Distressed by recent news of the “Erin Brockovich” contaminant in your drinking water?
Don’t panic. Health recommendations are based on decades of exposure, so drinking water exceeding those goals for one day or even for the next five years statistically doesn’t change your cancer risk that much, an Arizona State University scientist said.
A report, released by Environmental Working Group, found that more than 200 million Americans drink water that has more chromium-6 in it than California scientists recommend.
Chromium-6 gained national attention in the 1990s when then-legal clerk Erin Brockovich helped residents in Hinkley, Calif., settle a massive case against Pacific Gas and Electric Co. The electric utility had polluted the groundwater with cancer-causing chemicals, which Brockovich linked to illnesses in the town.
1. The California Office of Health Hazard Assessment set a public health goal of .02 parts per billion.
That means if you drink water containing that amount of chromium-6 over 70 years, you have no more than a one-in-a-million chance of getting cancer. The office determines such goals on health alone — economic or technical feasibility not included.
2. California set its legal limit to 10 parts per billion.
That gives you a 500-in-a-million chance of getting cancer from chromium-6 ingestion. The state arrived at that number based on health, economical and technical feasibility.
3.The U.S. Environmental Protection Agency allows for chromium levels to reach 100 parts per billion.
That lumps together chromium-6 and its benign cousin, chromium-3, but assumes that all of those particles are of the harmful variety. The limit reflects up to a 5,000-in-a-million chance of getting cancer. The federal government set this standard in 2001 based on skin reactions and is considering lowering the limit. But don’t expect a draft assessment until 2017. The EPA reported five years ago that chromium-6 is likely to cause cancer.
4. Chromium-6 leaches into water either naturally or from runoff from industries such as electroplating, leather tanning and textile.
Chromium is an abundant element in Earth’s crust, found in rocks, plants, soil, volcanic dust, humans and animals. Chromium-6 is created when chromium oxidizes. Around here, the contaminant occurs naturally.
5. The contaminant is pervasive.
Environmental Working Group found that Americans drink water exceeding the California goal in all 50 states.
6. Your utility is most likely well within that federal standard, but also within the California standard, if your water system serves at least 10,000 people.
Most utilities in Arizona reported average chromium-6 levels below 10 parts per billion. The testing doesn’t include everyone, though. The law required water utilities nationwide serving at least 10,000 people to test for chromium-6 from 2013 to 2015. A small fraction of small systems were required to test.
7. Home test kits for chromium-6 won’t tell you if you’re within California limits.
Consumer-testing products tend to detect chromium-6 in parts per million. In fact, it’s only been about 10 to 12 years since the technology was developed to measure at the levels we do today. If you’re worried about chromium in your well, you’ll likely have to submit samples to a laboratory to find out if you’re close to California’s health goal, said Paul Westerhoff, senior sustainability scientist of Arizona State University’s Julie Ann Wrigley Global Institute of Sustainability.
8. Techniques to reduce your exposure can be expensive and water intensive.
Reverse osmosis is a method often recommended to reduce your exposure to chromium-6. These systems can cost hundreds of dollars and require vigilance on your part to make sure they’re well maintained and updated with filter replacements on a strict schedule. The technology also wastes about 70 percent of the water it processes, Westerhoff said.
Standard carbon filters will not tackle chromium-6, but the Environmental Working Group has recommended one type of pour-through filter that does. It is unclear, however, whether the product by Zero Technologies filters chromium-6 down to the California standard. The company certifies the product to reduce chromium levels to less than 50 parts per billion.
9. Make sure the product you buy is certified by the National Sanitation Foundation.
The blue “NSF” label ensures that the product’s claim has been validated.
10. ASU and other university researchers are working with private industry to develop another way to reduce chromium-6 exposure at home.
The team aims to release a technology in about a year that revamps the standard carbon-block filter to combat chromium-6. The work is partially funded by a $3.5 million National Science Foundation grant and membership fees from 15 industrial partners. The goal is to create a filter that is easier to use and less expensive than reverse osmosis, said Westerhoff, who is part of the team.
Phoenix: 7.9 parts per billion.
Glendale: 6.4 parts per billion.
Avondale: 6.1 parts per billion.
Gilbert: 5.9 parts per billion.
Mesa: 5.6 parts per billion.
Chandler: 5.2 parts per billion.
Peoria: 3.8 parts per billion.
Queen Creek: 3.5 parts per billion.
Scottsdale: 3.5 parts per billion.
Tempe: 2.3 parts per billion.
Source: Environmental Working Group
Note: These numbers reflect an average of all water samples taken from each city’s test sites, which includes lesser-used sources such as wells.
Connect here to read a MSNBC story featuring Ms. Chelsea Francis – a MS graduate a few years ago from our group.
Read here about doctoral candidate Xiangyu Bi’s recent award
Each year the ERC presents the award to a promising young researcher in environmentally sustainable manufacturing from its more than 12 participating universities. This is the 15th year that Anna Karecki, Simon’s mother, has traveled from New York to Tucson to personally present the award. “This was Simon’s family,” she said to the group. “With this award I hope to encourage these brilliant young people, who are so passionate about their work, like Simon was.”
The 2016 Simon Karecki Award was given to Xiangyu Bi, a doctoral student in civil, environmental and sustainable energy at Arizona State University. The Karecki Award Board selected Bi for maintaining an excellent academic record while working on several research projects and teaching lab courses. He has been recognized by several other groups, including the Sustainable Nanotechnology Organization.
“Potential Environmental Impacts and Antimicrobial Efficacy of Silver- and Nanosilver-Containing Textiles”
Environmental Science & Technology
Anti-odor athletic clothes containing silver nanoparticles have gained a foothold among exercise buffs, but questions have arisen over how safe and effective they are. Now scientists report in ACS’ journal Environmental Science & Technologythat silver nanoparticles and coatings do wash off of commercially available garments in the laundry but at negligible levels. They also found that even low concentrations of silver on clothing kept microbes at bay.
Thanks to their antimicrobial properties, silver nanoparticles are found in an increasing array of products such as food packaging, bandages and textiles. At the same time, scientists have been studying the possible effects silver nanoparticles might have on the environment and human health. Studies have shown that the particles can be toxic, but their safety is dependent on a number of factors such as size and dose. Few studies, however, have examined both their effectiveness in products and their potential for harm. Paul K. Westerhoff and colleagues wanted to see how the design of antimicrobial clothes affects how well they stand up to washing and their potential to leach silver into the environment.
The researchers tested commercial athletic shirts in which the silver nanoparticles were incorporated in one of four different ways. Washing the shirts released a range of silver concentrations, depending on how the nanoparticles were attached. But overall, the resulting toxicity of the wastewater due to its silver content was negligible to zebrafish embryos — a model animal used in toxicity studies. And after washing, the shirts still retained their antimicrobial effect even if their remaining metal concentration was low. The researchers also say, however, that the remaining silver will leach out over time when the clothes are discarded in landfills. They recommend keeping the initial metal concentration in these products low to help reduce their environmental impact while still maintaining their ability to fight off microbes.
The authors acknowledge funding from the U.S. Environmental Protection Agency.
We’ve all been told not to waste our money, but it turns out that every year millions of dollars are literally gone to waste.
Millions of dollars worth of valuable metals get flushed into our sewage every year, according to a 2015 study published in Environmental Science & Technology. For a city of about a million people, there is around 13 million dollars worth of metals.
“Each person discharges about 10 dollars worth of gold a year,” said Paul Westerhoff, Professor of Environmental and Sustainable Engineering at Arizona State University and author of the study.
He began studying the hidden treasures in our sewage sludge by first studying if nanoparticles from toothpaste made it past water purification. He found so much more.
“We found titanium dioxide that looks like it came from your toothpaste,” he said. “But then we also started to find gold nuggets and silver nuggets.”
These metals not only come from industrial processes, jewelry manufacturing and mining, but from our own bodies as well. Teeth fillings, decorative gold on food, as well as many pharmaceuticals can contribute to the metal we flush down the toilet.
“There’s a lot more gold floating around than you’d imagine,” said Westerhoff.
If this metal were to be mined, it could reduce the costs of getting rid of solids by 25 percent, and could potentially reduce a city’s taxes.
“Someone’s not going to come in and make money selling gold, but it will decrease the cost of treating waste water,” Westerhoff said.
Cities like Japan are already extracting metals from their sewage. Other cities like Switzerland are incinerating their solids with the idea of mining it in the future when technology is more advanced, and the process is less energy intensive.
“You can find ways to concentrate the metals down and then apply some of the same techniques as mining companies,” said Westerhoff.
Science can be dirty business, but Westerhoff keeps a good humor about it.
“I understand that there’s significant value in trying to communicate what we do in science to the public,” he said. “If it means talking about gold in poop, that’s good for me.”
Harvesting water from the atmosphere? It’s possible, says ASU engineer Paul Westerhoff. And it could be a viable option if drought and climate change threaten to dry up our supply. Westerhoff was interviewed on the topic on KJZZ radio’s news program “The Show.”
Announcement coincides with the White House Water Summit and World Water Day
Click here to our Nanosystems ERC on NanoEnabled Water Treatment Systems
(March 23, 2016) As a part of the White House Water Summit held yesterday on World Water Day, the Federal agencies participating in the National Nanotechnology Initiative (NNI) announced the launchof a Nanotechnology Signature Initiative (NSI), Water Sustainability through Nanotechnology: Nanoscale Solutions for a Global-Scale Challenge.
Access to clean water remains one of the world’s most pressing needs. As today’s White House Office of Science and Technology blog post explains, “the small size and exceptional properties of engineered nanomaterials are particularly promising for addressing the key technical challenges related to water quality and quantity.”
“One cannot find an issue more critical to human life and global security than clean, plentiful, and reliable water sources,” said Dr. Michael Meador, Director of the National Nanotechnology Coordination Office (NNCO). “Through the NSI mechanism, NNI member agencies will have an even greater ability to make meaningful strides toward this initiative’s thrust areas: increasing water availability, improving the efficiency of water delivery and use, and enabling next-generation water monitoring systems.”
Nanotechnology Signature Initiatives are areas that the NNI member agencies have identified as poised for significant advances through enhanced and focused coordination and collaboration. The complete list of NSIs with corresponding details can be found on Nano.gov.
For further information, see the announcements by the White House at: