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Monday, September 15, 2014

Nuclear waste eaters: Scientists discover hazardous waste-eating bacteria

Date: September 9, 2014
Source: University of Manchester
Summary: Tiny single-cell organisms discovered living underground could help with the problem of nuclear waste disposal, say researchers. Although bacteria with waste-eating properties have been discovered in relatively pristine soils before, this is the first time that microbes that can survive in the very harsh conditions expected in radioactive waste disposal sites have been found.

The bacterium (inset) was found in soil samples in the Peak District.
Credit: Image courtesy of University of Manchester

Tiny single-cell organisms discovered living underground could help with the problem of nuclear waste disposal, say researchers involved in a study at The University of Manchester.

Although bacteria with waste-eating properties have been discovered in relatively pristine soils before, this is the first time that microbes that can survive in the very harsh conditions expected in radioactive waste disposal sites have been found. The findings are published in the ISME (Multidisciplinary Journal of Microbial Ecology) journal.

The disposal of our nuclear waste is very challenging, with very large volumes destined for burial deep underground. The largest volume of radioactive waste, termed 'intermediate level' and comprising of 364,000m3 (enough to fill four Albert Halls), will be encased in concrete prior to disposal into underground vaults. When ground waters eventually reach these waste materials, they will react with the cement and become highly alkaline. This change drives a series of chemical reactions, triggering the breakdown of the various 'cellulose' based materials that are present in these complex wastes.

One such product linked to these activities, isosaccharinic acid (ISA), causes much concern as it can react with a wide range of radionuclides -- unstable and toxic elements that are formed during the production of nuclear power and make up the radioactive component of nuclear waste. If the ISA binds to radionuclides, such as uranium, then the radionuclides will become far more soluble and more likely to flow out of the underground vaults to surface environments, where they could enter drinking water or the food chain. However, the researchers' new findings indicate that microorganisms may prevent this becoming a problem.

Working on soil samples from a highly alkaline industrial site in the Peak District, which is not radioactive but does suffer from severe contamination with highly alkaline lime kiln wastes, they discovered specialist "extremophile" bacteria that thrive under the alkaline conditions expected in cement-based radioactive waste. The organisms are not only superbly adapted to live in the highly alkaline lime wastes, but they can use the ISA as a source of food and energy under conditions that mimic those expected in and around intermediate level radwaste disposal sites. For example, when there is no oxygen (a likely scenario in underground disposal vaults) to help these bacteria "breath" and break down the ISA, these simple single-cell microorganisms are able to switch their metabolism to breathe using other chemicals in the water, such as nitrate or iron.

The fascinating biological processes that they use to support life under such extreme conditions are being studied by the Manchester group, as well as the stabilizing effects of these humble bacteria on radioactive waste. The ultimate aim of this work is to improve our understanding of the safe disposal of radioactive waste underground by studying the unusual diet of these hazardous waste eating microbes. One of the researchers, Professor Jonathan Lloyd, from the University's School of Earth, Atmospheric and Environmental Sciences, said: "We are very interested in these Peak District microorganisms. Given that they must have evolved to thrive at the highly alkaline lime-kiln site in only a few decades, it is highly likely that similar bacteria will behave in the same way and adapt to living off ISA in and around buried cement-based nuclear waste quite quickly.

"Nuclear waste will remain buried deep underground for many thousands of years so there is plenty of time for the bacteria to become adapted. Our next step will be to see what impact they have on radioactive materials. We expect them to help keep radioactive materials fixed underground through their unusual dietary habits, and their ability to naturally degrade ISA."

Story Source: The above story is based on materials provided by University of Manchester.

Thursday, September 11, 2014

To clean air and beyond: Catching greenhouse gases with advanced membranes

Date: September 4, 2014
Source: Institute for Integrated Cell-Material Sciences, Kyoto University
Summary: An advanced membrane has been developed for the purpose of cleaning up greenhouse gases. The membranes are cheaper, long-lasting, selective and highly permeable compared to commercially available ones.

PIM-1 is a highly permeable membrane compared with commercially available ones. The orange balloon on the left illustrates this point as a higher volume of nitrogen gas is able to pass through PIM-1 into the balloon compared with the membrane on the right, connected to the pink balloon.

Greenhouse gases, originating from industrial processes and the burning of fossil fuels, blanket the Earth and are the culprits behind current global warming woes. The most abundant among them is carbon dioxide, which made up 84% of the United States' greenhouse gases in 2012, and can linger in Earth's atmosphere for up to thousands of years.

Countries all over the world are looking to reduce their carbon dioxide footprint. However, carbon dioxide is essentially a waste product with little immediate commercial value and large treatment costs. Therefore, new low-cost technologies are sorely needed to incentivize greenhouse gas capture by industry.

Easan Sivaniah -- an associate professor at Kyoto University's Institute for Integrated Cell-Material Sciences (iCeMS) -- led an international team of researchers from iCeMS and the University of Cambridge to create an advanced membrane capable of rapidly separating gases.

The membrane they worked on, referred to as PIM-1, is "typically embedded with a network of channels and cavities less than 2 nm in diameter that can trap gases of interest once they enter," said Qilei Song, who was involved in the study. "The only problem is that their intrinsic properties make them rather flimsy and their starting selectivity is weak."

To overcome PIM-1's weaknesses, Sivaniah's team heated PIM-1 at temperatures ranging from 120 to 450 °C in the presence of oxygen, a process referred to as thermal oxidation. "Oxygen, under high temperatures, chemically reacts with PIM-1 to reinforce the strength of channels while controlling the size of so-called gate openings leading into the cavities, which allows for higher selectivity," said Song.

The resulting improved PIM-1 was found to be twice as selective for carbon dioxide while allowing air to pass through it 100 times faster compared with commercially available polymers. PIM-1 can also be used for other applications such as capturing carbon dioxide from the burning of fossil fuels, enriching the oxygen content in air for efficient combustion engines, hydrogen gas production, and processes to generate plastic.

"Basically, we developed a method for making a polymer that can truly contribute to a sustainable environment," said Sivaniah. "And because it is affordable and long-lasting, our polymer could potentially cut the cost of capturing carbon dioxide by as much as 1000 times."

Story Source: The above story is based on materials provided by Institute for Integrated Cell-Material Sciences, Kyoto University.

Thursday, September 4, 2014

Clean air halves health costs in Chinese city

Air pollution regulations over the last decade in Taiyuan, China, have substantially improved the health of people living there, accounting for a greater than 50% reduction in costs associated with loss of life and disability between 2001 and 2010, according to researchers at the Columbia Center for Children's Environmental Health (CCCEH) at the Mailman School of Public Health, the Shanxi Medical University, the Center of Diseases Control and Prevention of Taiyuan Municipality, and Shanghai Fudan University School of Public Health.

The study is the first to document the health and economic benefits of policies to reduce the burden of air pollution in a highly polluted area of China, and provides a model to measure how policies to improve air quality can protect human health. Results appear online in the journal Environment International.

Taiyuan, the capital of Shanxi Province, is a major center in China for energy production and metallurgical industries. To combat air pollution, the Shanxi Provincial Government implemented many new environmental policies and regulations. Between 2000 and 2012, these included mandating the closure of many polluting sources, auditing companies that produced large amounts of toxic and hazardous materials, setting pollutant emissions standards, and promoting energy efficiency and pollution reduction. As a result, concentrations of particulate matter (PM10) declined by more than half, from 196 µg/m3 in 2001 to 89 µg/m3 in 2010, as measured at eight sites throughout the city.

Reductions in particulate matter between 2001 and 2010 were associated with 2,810 fewer premature deaths, 31,810 fewer hospital admissions, 141,457 fewer outpatient visits, 969 fewer ER visits, and 951 fewer cases of bronchitis. The team estimated that there were more than 30,000 fewer DALYs -- disability-adjusted life years, a standard measure of the loss of healthy years -- attributed to air pollution in Taiyuan in 2010 compared to 2001. The cost of premature death due to air pollution decreased by 3.83 billion Yuan, or approximately $621 million.

Particulate matter is released by coal-burning plants and other sources. These small particles can lodge themselves deeply in human lungs, and are associated with heart and lung conditions and premature death.

"Our results suggest that the air quality improvement from 2001 to 2010 resulted in substantial health benefits. In fact, the health and financial impacts of air pollution could potentially be greater than those reported due to our selection of only a few health outcomes that could be quantitatively estimated and translated into monetary values," says lead investigator Deliang Tang, DrPH, associate professor of Environmental Health Sciences at the Mailman School of Public Health.

The study builds on similar research from CCCEH in China, showing improvements in air quality were linked with improved childhood developmental scores.

"Over the last ten years, our research in two Chinese cities have demonstrated that strong government policies to reduce air pollution can result in substantial health benefits for children and adults," says Frederica Perera, PhD, director of the Columbia Center for Children's Environmental Health at the Mailman School of Public Health. "These findings make the argument for stronger and broader regulations in Chinese cities where air pollution remains a serious health problem."

According to the Chinese Ministry of Environmental Protection, only three of 74 cities the government monitors meet minimum air standards. In March, Premier Li Kequiang announced that the country would "declare war against pollution," by reducing particulate matter and closing outdated industrial plants.

Story Source: Columbia University's Mailman School of Public Health.

Friday, August 22, 2014

Switzerland's new natural swimming pool does away with the chemicals

The Naturbad Riehen swimming pool is entirely chemical-free (Photo: Helen Schneider).

Image Gallery (10 images)

A whiff of chlorine is virtually synonymous with taking a dip in a swimming pool. While it helps to kill off bacteria, it also serves as a subtle reminder that you are wading around in chemically treated water (if tasting the odd mouthful just isn't enough). Switzerland's Naturbad Riehen swimming pool is entirely chemical-free, relying instead on a biological filter system to provide clean and natural water for thousands of patrons, no itchy red eyes in sight.

A town of around 20,000 people, Riehen sits just outside of Basel on the Swiss-German border. This section of the border wraps around Riehen in such a way that in 2006, the town's old swimming pool had to be demolished to make way for a tunnel connecting two German cities on either side. With the controversial roadway completed in 2013, the people of Riehen were quick to reclaim their territory.

"The citizens wanted their pool back and believed that a natural swimming pool would suit their interest in bathing, swimming and playing, just as well as a traditional pool," Christian Lupp, Recreation and Sports representative from the Municipality of Riehen tells Gizmag. "Furthermore, there was the understanding that the natural water is better for the skin and eyes and feels smoother and softer".

Features include a wading pool for toddlers, a separate pool with a sloping gravel beach.

The first man-made natural swimming pools date back to the early 1980s in Austria, though these were largely for private use. The precise mechanics vary between each natural pool, but they typically contain the swimming water inside a membrane and then a separate water regeneration zone to clean it. Aquatic plants kill off germs while absorbing nutrients from the water for growth. Often the water is pumped across the surface of rocks or gravel to which the bacteria clings, functioning as a natural filter.

Since the 1980s, the concept has been commercialized and spread to different parts the world. Natural pools for public use have popped up in Germany, the UK and one is currently under construction at Webber Park in Minneapolis, set to be the first in the United States. Lupp says a point of difference for the Naturbad Riehen is that it's au naturel from the ground up, allowing for better integration of the pool's natural technology with its wooden infrastructure.

"Many other projects are conversions of traditional pools," he explains. "Our pool is absolutely built from zero, allowing the extraordinary possibility of a holistic design and a combination between the natural technology and its according architecture."

An on-site cafe offers refreshments and snacks, with wooden decking and grass.

Swiss architects Herzog & de Meuron designed Riehen's new swimming pool to accommodate the town's families and blend in with the greenery that surrounds. Features include a wading pool for toddlers, a separate pool with a sloping gravel beach, a water-slide, a 25-meter (82 ft) lap pool and a diving board. An on-site cafe offers refreshments and snacks, with wooden decking and grass providing a place for some time out.

Officially opening for business in mid-June, the Naturbad Riehen is equipped to deal with 2,000 daily visitors. We're guessing the residents of Riehen are pretty happy with their new pool, with the possible exception of those in the business of selling swimming goggles.

Source: Naturbad Riehen

Wednesday, August 20, 2014

New Tel Aviv University building is "greenest in the Middle East"

Date: August 13, 2014

A new building has been opened for Tel Aviv University's Porter School of Environmental Studies.

You'd hope that a school of environmental studies would practice what it preaches. Well, Tel Aviv University's Porter School of Environmental Studies does so emphatically. Its newly inaugurated building is, it says, the first LEED Platinum-certified in Israel and the greenest in the Middle East.

Leadership in Energy & Environmental Design (LEED) certification has become a widely recognized mark of environmental good practice in the design, construction, maintenance and operation of buildings. Amongst the LEED Platinum-certified buildings that were recently featured, BioCasa 82 in Italy was claimed to be Europe's first LEED Platinum home, the Munich-based NuOffice was claimed to be the world's most sustainable office building and Dubai's Chance Initiative was claimed to be the world's most sustainable building overall.

The PSES building was designed in collaboration by Geotectura Studio and Axelrod Grobman Architects with the aim of being a "living laboratory." As well as providing spaces for education and learning, it was decided that the building should be a demonstrative educational platform in itself, with users and visitors able to examine the environmental technologies installed therein.

The Capsule in the PSES building houses a workshop and meeting space (Photo: Shai Epstein).

Amongst the public and education spaces in the building are an auditorium, a spacious atrium that can be used for meetings and exhibitions, classrooms, lecture halls, research offices, meeting rooms and offices. The temperature in the PSES building is regulated using a solar energy-powered air conditioning system, along with a structure design optimized for local conditions. Grey water, meanwhile, is recycled and reused elsewhere in the building.

In addition to a green roof, the building features an "EcoWall" which is described as an iconic element of the building's aesthetic, but is also a functional part of its environmental efforts. The EcoWall provides protection from the sun in the building's atrium, but also capitalizes on its south-facing orientation by hosting the array of solar panels used to power the building's air conditioning. Terraces along the EcoWall can also be used for experimental research.

The PSES building has a green roof (Photo: Shai Epstein).

The PSES building also features a striking Capsule element as part of its design. The Capsule is a 3D elliptical structure that's suspended in the building's atrium and that pokes out of the EcoWall. Housed in the Capsule is a workshop and meeting room with "state of the art multimedia technology." The external surface of the Capsule is covered in connected LEDs that are used to display environmental information, such as energy statistics of the PSES Building and pollution levels in Tel Aviv.

The PSES building was inaugurated in May and held its first graduation ceremony in June.

The video below shows an animated rendering of the PSES building.

Source: Porter School of Environmental Studies

Monday, August 4, 2014

Scientists Caution Against Exploitation of Deep Ocean

Date: July 30, 2014
Source: Oregon State University
Summary: The world's oceans are vast and deep, yet rapidly advancing technology and the quest for extracting resources from previously unreachable depths is beginning to put the deep seas on the cusp of peril, an international team of scientists has warned.


A new OSU study looks at how exploiting the ocean's vast resources have put it in peril.
Credit: Image courtesy of Oregon State University

The world's oceans are vast and deep, yet rapidly advancing technology and the quest for extracting resources from previously unreachable depths is beginning to put the deep seas on the cusp of peril, an international team of scientists warned this week.

In an analysis in Biogeosciences, which is published by the European Geosciences Union, the researchers outline "services" or benefits provided by the deep ocean to society. Yet using these services, now and in the future, is likely to make a significant impact on that habitat and what it ultimately does for society, they point out in their analysis.

"The deep sea is the largest habitat on Earth, it is incredibly important to humans and it is facing a variety of stressors from increased human exploitation to impacts from climate change," said Andrew Thurber, an Oregon State University marine scientist and lead author on the study. "As we embark upon greater exploitation of this vast environment and start thinking about conserving its resources, it is imperative to know what this habitat already does for us."

"Our analysis is an effort to begin to summarize what the deep sea provides to humans because we take it for granted or simply do not know that the deep sea does anything to shape our daily lives," he added. "The truth is that the deep sea affects us, whether we live on the coast or far from the ocean -- and its impact on the globe is pervasive."

The deep sea is important to many critical processes that affect Earth's climate, including acting as a "sink" for greenhouse gases -- helping offset the growing amounts of carbon dioxide emitted into the atmosphere. It also regenerates nutrients through upwelling that fuel the marine food web in productive coastal systems such as the Pacific Northwest of the United States, Chile and others. Increasingly, fishing and mining industries are going deeper and deeper into the oceans to extract natural resources.

"One concern is that many of these areas are in international waters and outside of any national jurisdiction," noted Thurber, an assistant professor (senior research) in Oregon State's College of Earth, Ocean, and Atmospheric Sciences. "Yet the impacts are global, so we need a global effort to begin protecting and managing these key, albeit vast, habitats."

Fishing is an obvious concern, the scientists say. Advances in technology have enabled commercial fisheries to harvest fish at increasing depths -- an average of 62.5 meters deeper every decade, according to fisheries scientists. This raises a variety of potential issues.

"The ability to fish deeper is shifting some fisheries to deeper stocks, and opening up harvests of new species," Thurber said. "In some local cases, individual fisheries are managed aggressively, but due to how slow the majority of the fish grow in the deep, some fish populations are still in decline -- even with the best management practices."

The orange roughy off New Zealand, for instance, is both a model of effective and conservation-based management, yet its populations continue to decline, though at a slower rate than they would have experienced without careful management, Thurber noted.

"We also have to be concerned about pollution that makes its way from our continental shelves into the deep sea," he added. "Before it was 'out of sight, out of mind.' However, some of the pollution can either make it into the fish that we harvest, or harm the fishers that collect the fish for us. It is one of the reasons need to identify how uses of the deep sea in the short term can have long-term consequences. Few things happen fast down there."

Mining is a major threat to the deep sea, the researchers point out in their analysis. In particular, the quest for rare earth and metal resources, which began decades ago, has skyrocketed in recent years because of their increased use in electronics, and because of dwindling or limited distribution of supplies on land. Mining the deep ocean for manganese nodules, for example -- which are rich in nickel -- requires machines that may directly impact large swaths of the seafloor and send up a sediment plume that could potentially affect an even larger area, the scientists note.

These mining resources are not limited to muddy habitats, Thurber pointed out. Massive sulfides present at hydrothermal vents are another resource targeted by mining interests.

"The deep sea has been an active area for oil and gas harvesting for many years," he said, "yet large reservoirs of methane and other potential energy sources remain unexploited. In addition to new energy sources, the potential for novel pharmaceuticals is also vast.

"There are additional threats to these unique habitats, including ocean acidification, warming temperatures and possible changes to ocean circulation through climate change."

The next step, the researchers say, is to attach an economic value to both the services provided by the deep sea -- and the activities that may threaten those services.

"What became clear as we put together this synopsis is that there is vast potential for future resources but we already benefit greatly through this environment," Thurber said. ""What this means is that while the choices to harvest or mine will be decided over the coming decades, it is important to note that the stakeholders of this environment represent the entire world's population."

"The Bible, the Koran, the Torah, and early Greek texts all reference the deep sea," he added. "Maybe it's time for all of us to take a closer look at what it has to offer and decide if and how we protect it."

Source: The above story is based on materials provided by Oregon State University.

Wednesday, July 9, 2014

Oklahoma earthquakes induced by wastewater injection by disposal wells, study finds

House damage in central Oklahoma from the magnitude 5.6 earthquake on Nov. 6, 2011.

Credit: Brian Sherrod, USGS

The dramatic increase in earthquakes in central Oklahoma since 2009 is likely attributable to subsurface wastewater injection at just a handful of disposal wells, finds a new study to be published in the journal Science on July 3, 2014.

The research team was led by Katie Keranen, professor of geophysics at Cornell University, who says Oklahoma earthquakes constitute nearly half of all central and eastern U.S. seismicity from 2008 to 2013, many occurring in areas of high-rate water disposal.

"Induced seismicity is one of the primary challenges for expanded shale gas and unconventional hydrocarbon development. Our results provide insight into the process by which the earthquakes are induced and suggest that adherence to standard best practices may substantially reduce the risk of inducing seismicity," said Keranen. "The best practices include avoiding wastewater disposal near major faults and the use of appropriate monitoring and mitigation strategies."

The study also concluded:

  • Four of the highest-volume disposal wells in Oklahoma (~0.05% of wells) are capable of triggering ~20% of recent central U.S. earthquakes in a swarm covering nearly 2,000 square kilometers, as shown by analysis of modeled pore pressure increase at relocated earthquake hypocenters.
  • Earthquakes are induced at distances over 30 km from the disposal wells. These distances are far beyond existing criteria of 5 km from the well for diagnosis of induced earthquakes.
  • The area of increased pressure related to these wells continually expands, increasing the probability of encountering a larger fault and thus increasing the risk of triggering a higher-magnitude earthquake.

"Earthquake and subsurface pressure monitoring should be routinely conducted in regions of wastewater disposal and all data from those should be publicly accessible. This should also include detailed monitoring and reporting of pumping volumes and pressures," said Keranen. 'In many states the data are more difficult to obtain than for Oklahoma; databases should be standardized nationally. Independent quality assurance checks would increase confidence. "

Source: The above story is based on materials provided by Cornell University.

Journal Reference: K. M. Keranen, M. Weingarten, G. A. Abers, B. A. Bekins, and S. Ge. Sharp increase in central Oklahoma seismicity since 2008 induced by massive wastewater injection. Science, 3 July 2014 DOI: 10.1126/science.1255802