It All Starts with Science

This Week in EPA Science

By Kacey Fitzpatrick

Happy fall! Here’s the latest in EPA science.

research_recap_250Testing Salt-Tolerant Algae as a Desalination Method
There is a large volume of brackish water (salt water and fresh water mixed together) in many arid areas of the world, but current desalination methods are expensive and use a lot of energy. Recently, some of our scientists investigated the use of salt tolerant algae—also known as halophytic algae—as a natural and sustainable method to decrease salinity in brackish water and seawater. Learn more about this research in the blog Using Green to Combat Saline: Testing Salt-Tolerant Algae as a Desalination Method.

EPA’s Integrated Risk Information System Assessment of Ammonia
There are a number of ways that humans can be exposed to ammonia. To characterize the potential health effects, EPA recently released an Integrated Risk Information System (IRIS) assessment that looks at the noncancer health hazards that may result from inhalation of ammonia. Learn more about the assessment in the blog EPA’s Integrated Risk Information System Assessment of Ammonia.

The Arsenic Sensor Prize Competition
Interested in helping protect our nation’s drinking water? EPA and the U.S. Bureau of Reclamation are joining forces to launch the Arsenic Sensor Prize Competition for the development of new technology to detect arsenic in water. Learn more about the upcoming competition in the blog We’re Sensing a Change in Water Monitoring: Introducing the Arsenic Sensor Prize Competition.

Water Quality Research Grants
This week EPA announced funding to six universities to work with local communities to better understand the economic value of water quality. This research will provide a critical link between water quality science and the monetary value of the services that healthy waterways provide. Learn more about the grants in this press release.

Need more science? Mark you calendars for some of these upcoming events at EPA.

Now get outside and enjoy the gorgeous fall weather.

About the Author: Kacey Fitzpatrick is a writer working with the science communication team in EPA’s Office of Research and Development. She is a regular contributor to It All Starts with Science and the founding writer of “The Research Recap.”

Editor's Note: The opinions expressed here are those of the author. They do not reflect EPA policy, endorsement, or action.

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Using Green to Combat Saline: Testing Salt-Tolerant Algae as a Desalination Method

By Christina Burchette

In 2014, the Lawrence Berkeley National Lab Institute for Globally Transformative Technologies released a report called “The 50 most critical scientific & technological breakthroughs required for sustainable global development.” Of all the technologies the report highlighted, the number one priority on the list was a new method for desalinating water. That’s because water security is closely linked with energy and food security issues—world water demand is rising, and more than 70% is used for agriculture.

Algae water sample, desalinated sample, desalinated and filtered water sample

From left: Desalinated and filtered water sample, desalinated water sample, algae water sample

There is a large volume of brackish water (salt water and fresh water mixed together) in many arid areas of the world, but current desalination methods are expensive and use a lot of energy, which means that most people who need them can’t use them. Finding a low-cost and renewable desalination method could help alleviate some of the effects of water scarcity, which is becoming an increasingly apparent problem as we continue to feel the impacts of climate change around the world.

So how do we find a sustainable, low-cost, and energy efficient way to remove salinity from water, making it suitable for drinking and agriculture? By harnessing the power of the ultimate technology: Mother Nature. Recently, some of our scientists investigated the use of salt tolerant algae—also known as halophytic algae—as a natural and sustainable method to decrease salinity in brackish water and seawater. Some species of salt-tolerant algae can absorb up to 50 times more salt than the concentration of salt in the water they inhabit, making them a perfect (and natural!) way to desalinate water for potable use. In addition, the growing algae can be used to mitigate carbon dioxide from point source emissions. Once the algae has been used for desalination, it can then be harvested and used as a raw material for biofuel production to reduce the use of fossil fuels.

The photobioreactor looks like a large glass tube

The photobioreactor

To gather insight about which algae species would perform the best during experiments, researchers visited an algae bank at the University of Texas at Austin. After screening more than 12 different types of algae species and noting special conditions like pH, micronutrient requirements, and light cycle sensitivity, researchers picked four types of halophytic algae that had the best salt uptake rates.

They then grew and tested the algae for its salt-removal capabilities in a photobioreactor, which is a vessel that housed the algae and provided it with the light it needed to mature. Researchers manipulated the algae’s breeding and feeding conditions to optimize growth rate, survival rate, and absorbency and discovered that they could remove up to 30% salinity in brackish water samples in one treatment stage.

While complete desalination can’t be achieved with algae alone, this method can serve as a pretreatment to other desalination technologies—reducing the energy footprint and financial costs of desalination while making the process more sustainable. EPA researchers are currently comparing the sustainability advantages of biodesalination technology with conventional approaches. This research highlights not only what our researchers are doing to provide potential solutions to global water issues, but also the amazing things that can be achieved with natural resources and a little bit of science.

Various algae species in smaller bioreactors

Various algae species in smaller bioreactors

About the Author: Christina Burchette is an Oak Ridge Associated Universities contractor and writer for the science communication team in EPA’s Office of Research and Development.

Editor's Note: The opinions expressed here are those of the author. They do not reflect EPA policy, endorsement, or action.

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EPA’s Integrated Risk Information System Assessment of Ammonia

By Salina Tewolde and Lou D’Amico, Ph.D.

The first thing that probably comes to your mind when I say “ammonia” is that household product you use to clean just about anything in your house. Besides being used as an all-purpose cleaner, ammonia also occurs naturally in air, soil, and water. As you’re reading this, you’re producing ammonia too – it’s used in nucleic acid and protein synthesis, and helps your body maintain its acid-base balance – all part of normal biological processes.

The largest and most significant use of ammonia is in agricultural fertilizers, which represents about 80% of commercially produced ammonia. Ammonia is also used in food products as an antimicrobial agent, in water purification, and in refrigeration systems. It’s also an important chemical intermediate in the production of pharmaceuticals and other chemicals, and is used to reduce nitrogen oxide emissions from combustion sources like some industrial boilers and diesel engines. Some major sources of ammonia gas come from leaks and spills during the production, storage, or processing stages of the chemical. Other sources include decaying manure from livestock, application of fertilizers in agricultural, and sewage or wastewater emissions in the environment. EPA’s Toxic Release Inventory reports that over 150 million pounds of ammonia was released from reporting facilities in 2014.

There are a number of ways that humans can be exposed to ammonia. The most common route of exposure is through breathing air that contains ammonia. Humans can be exposed to ammonia gas from household cleaning products or through direct skin contact via products that contain the chemical. Livestock and poultry farmers that work in animal feeding operations or confinement areas can be exposed to ammonia released from animal waste, and farmers can be exposed when applying ammonia-containing fertilizers to fields.

IRIS spelled out with flowers in the backgroundTo characterize the potential health effects that humans can acquire from inhaling high concentrations of ammonia, EPA recently released an Integrated Risk Information System (IRIS) assessment that looks at the noncancer health hazards that may result from inhalation of ammonia.

EPA’s assessment evaluates chronic inhalation exposure to ammonia, observed at levels that exceed naturally-occurring ammonia concentrations. Human and animal studies showed that inhalation exposure had an effect on the respiratory tract in humans, which is the site of direct contact when ammonia is inhaled. This hazard determination was based on findings from multiple epidemiology studies in human populations exposed to ammonia in different settings (workers in industrial, cleaning and agricultural settings, volunteers exposed for up to 6 hours under controlled conditions, as well as case reports) and animals (short-term and subchronic studies in several species and across different exposure patterns). Short-term inhalation exposure to high levels of ammonia in humans can cause irritation and serious burns in the mouth, lungs, and eyes. Chronic exposure to airborne ammonia may increase the risk of respiratory irritation, cough, wheezing, tightness in the chest, and decreased lung function.

EPA’s IRIS assessment includes an estimate of the amount of ammonia that one can breathe every day for a lifetime that is likely to be without harmful health effects. This is known as an inhalation reference concentration, or RfC. The RfC was derived from an occupational study by Holness et al. (1989) that looked at the relationship between decreased lung function and long-term exposure to ammonia from workers at a soda ash plant. Ammonia was last evaluated by the IRIS Program in 1991, and as a result of the reevaluation posted this week, the RfC is five-fold higher (less stringent) than what was previously on the IRIS database. You can learn as much as you care to about ammonia inhalation toxicity through either reading the Toxicological Review on the IRIS Ammonia webpage, or getting the highlights through the accompanying IRIS Summary.

IRIS assessments go through rigorous review prior to finalization. This ammonia assessment was reviewed by EPA’s program offices and regions and other federal agencies, as well as external peer review by the Science Advisory Board Chemical Assessment Advisory Committee. The public also had opportunity to comment. All of this information is available on the IRIS chemical-specific page for ammonia, and demonstrates the IRIS Program’s commitment to transparency while providing high quality, publicly available information on the toxicity of chemicals to which the public might be exposed.

Reference:  Holness, DL; Purdham, JT; Nethercott, JR. (1989). Acute and chronic respiratory effects of occupational exposure to ammonia. AIHA J 50: 646-650.

About the Authors: Salina Tewolde is a student contractor and writer working with the science communication team in EPA’s Office of Research and Development. Lou D’Amico is the Acting Communications Director for the National Center for Environmental Assessment, which houses the IRIS Program.

Editor's Note: The opinions expressed here are those of the author. They do not reflect EPA policy, endorsement, or action.

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Upcoming Events at EPA

By Michaela Burns

A new school semester means more learning! Not in school? You can still learn about science at EPA from some of our upcoming events.

Science To Achieve Results Tribal Grantee Progress Review Meeting
Tuesday, September 20th at 9 a.m. ET—Wednesday, September 21st at 5 p.m. ET  

Tribal landDon’t miss EPA’s Science to Achieve Results (STAR) Tribal Grantee Progress Review Meeting where we will receive research progress updates from the grantees awarded under the 2013 Request for Applications, Science for Sustainable and Healthy Tribes. EPA researchers will also share their work and present tools that can be applied to improve tribal health and well-being. Grantees, EPA, and other partners will discuss future opportunities for collaboration. Register now.

Food-Use Chemicals in ToxCast: Identification, Curation, and Evaluation
Thursday, September 22nd at 11 a.m. ET

pile of fruitIn this month’s CompTox Communities of Practice webinar, Agnes Karmaus, of Integrated Laboratory Systems, Inc., will discuss recently published research on food-relevant chemicals using the publicly available ToxCast high-throughput screening program.  Tune in and learn more.

 

 

Microbiomes in the Built Environment
Thursday, September 22ndat 11:00 a.m. ET

Control panel of the gas boiler for hot water and heatingA vast number of bacteria, viruses, fungi, and protozoa can live in built environments such as heating, ventilation, and air conditioning (HVAC) systems. These microbial communities or “microbiomes” are influenced by interactions with humans, animals, and plants and factors such as air flow, temperature, humidity, chemical exposures, and building materials. In this upcoming webinar, Dr. Brent Stephens, Associate Professor of Architectural Engineering at the Illinois Institute of Technology, will present an overview of the current science on microbiomes and the built environment. Register now!

Perfluorinated Chemicals: Analytics, Occurrence, and Treatment
Tuesday, September 27th at 2:00 p.m. ET

water faucet This month’s Small System’s webinar will focus on perfluorinated chemicals (PFCs) with an emphasis on perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS). Jody Shoemaker will present EPA’s analytical method for PFCs. This will cover the approach, performance data, holding time studies, and contamination issues. Marc Mills will present source water issues for PFCs, including the impact of wastewater effluents. Thomas Speth will cover what is known from the literature regarding PFOA and PFOS treatment for the technologies commonly employed by drinking water facilities. Register to learn more.

I-WASTE
Wednesday, September 28th at 3:00 p.m. ET

i-waste in actionThis month’s EPA Tools and Resources Webinar is on I-WASTE, a web-based decision support tool that organizes information related to managing waste resulting from natural disasters or terrorist attacks. It can be used by emergency response authorities, property owners, planners, treatment managers, as well as tribal, state, and local agencies responsible for making disposal decisions. Register for the webinar.

For more events head on over to the EPA research event page.

 About the Author: Michaela Burns is an Oak Ridge Associated Universities contractor and writer for the science communication team in EPA’s Office of Research and Development.

Editor's Note: The opinions expressed here are those of the author. They do not reflect EPA policy, endorsement, or action.

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We’re Sensing a Change in Water Monitoring: Introducing the Arsenic Sensor Prize Competition

By Lauren McAllister

Interested in helping protect our nation’s drinking water? EPA and the U.S. Bureau of Reclamation (USBR) are joining forces to launch the Arsenic Sensor Prize Competition for the development of new technology to detect arsenic in water.

info graphic about arsenic in drinking waterThe Safe Drinking Water Act requires that public water systems monitor regulated contaminants in drinking water to ensure public safety. Arsenic, a naturally occurring element, is one of the many drinking water contaminants actively monitored by drinking water systems because it can result in adverse health conditions, including an increased risk for a range of cancers. Measuring and testing for arsenic requires expensive instruments and lab work, as well as time. However, with new and emerging technologies, a more efficient arsenic monitoring technology could help to improve the monitoring system, reduce costs, and better protect human health and the environment.

Typically, samples are sent to a laboratory for analysis, with results available days to weeks later. New technology could accelerate this process by allowing for immediate detection of arsenic in water. This could reduce monitoring costs and help water utilities more effectively control treatment to remove arsenic from the drinking water supply.

The Arsenic Sensor Prize Competition aims to improve the existing process with upcoming and emerging technology.  The competition is not exclusively restricted to sensor developers, but seeks applicants from all fields. Applicant criteria includes anyone with ideas for how to rapidly, accurately, and cost-effectively measure arsenic in water.

The first phase of the Arsenic Sensor Prize Competition is scheduled to be launched in fall 2016. Entries will be judged and cash prizes will be awarded to winners. If you are interested in receiving notifications about the Arsenic Sensor Prize Competition, email PRIZE@usbr.gov with “Arsenic Sensor Prize Competition” in the subject line to join the email list. The official prize competition announcement will be posted on Challenge.gov.

About the Author: Lauren McAllister is an Oak Ridge Associated Universities contractor with the Innovation Team in EPA’s Office of Research and Development.

Editor's Note: The opinions expressed here are those of the author. They do not reflect EPA policy, endorsement, or action.

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This Week in EPA Science

By Kacey Fitzpatrickresearch_recap_250

Fall is right around the corner! Here’s a quick read before you head out to soak up the last few days of summer. Check out the latest in EPA science.

Integrated Risk Information System Program
Last week, EPA’s Integrated Risk Information System (IRIS) Program released the final assessment of trimethylbenzenes (TMBs). IRIS assessments provide health effects information and toxicity values for cancer and non-cancer health outcomes by using the best available scientific data. Learn about how to use the database in the blog Navigating a Newly Posted IRIS Assessment.

Interconnections in the Web of Life
For the past five years, researchers at EPA’s Western Ecology Division laboratory in Corvallis, Oregon have been composting their food scraps.  After noticing that large food scraps were being stirred-up overnight by something in their compost bins, they installed a self-operated wildlife camera inside one of the bins to identify the culprits. Read about what the researchers found in the blog Interconnections in the Web of Life.

Faces of EPA
Want to know more about what it’s like to work at EPA? Check out some of our featured researchers.

Meet Mary Kentula! Mary is an ecologist at EPA and the technical lead for EPA’s National Wetland Condition Assessment. Learn more about her work by watching the video Faces of EPA: Mary Kentula.

Meet Jana Compton! Jana is a research ecologist at EPA. Her research focuses on water quality and the impacts of nutrient pollution, such as nitrogen and phosphorous, on water quality. Learn more about her work by watching the video Faces of EPA: Jana Compton.

About the Author: Kacey Fitzpatrick is a writer working with the science communication team in EPA’s Office of Research and Development. She is a regular contributor to It All Starts with Science and the founding writer of “The Research Recap.”

Editor's Note: The opinions expressed here are those of the author. They do not reflect EPA policy, endorsement, or action.

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Navigating a Newly Posted IRIS Assessment

By Ashley Mayrianne Jones and Lou D’Amico, Ph.D.

Last week, EPA’s Integrated Risk Information System (IRIS) Program released the final assessment of trimethylbenzenes (TMBs). IRIS assessments provide health effects information and toxicity values for cancer and non-cancer health outcomes by using the best available scientific data.  Government and others combine IRIS toxicity values with exposure information to help characterize public health risks of chemical substances and use these assessments to support decisions designed to protect human health.

But you don’t need to wait until an assessment is finalized to learn more about the science that informs the Agency’s risk assessment and risk management decisions.

EPA is committed to transparency and providing information about its research and assessments. IRIS is no exception. Recently, EPA updated their web presence to help the general public find information faster and easier. As part of this update, EPA made significant changes to the IRIS website.

screenshot of the iris website

The online IRIS database contains crucial information from assessments on chemical substances that can be used to support hazard identification and dose-response assessment – two of the four steps in the human health risk assessment process.

So where to begin?  Well, the first place would be the IRIS Program home page at https://www.epa.gov/iris. There, you’ll find links to general program materials (such as the IRIS multi-year agenda), a calendar of public meetings and workshops, and an  “About IRIS” page, which explains the IRIS process and program history. You can also sign up for the IRIS listserv using the form at the top of the home page. Even more ways to stay up-to-date on IRIS activities are described under “Staying Connected.”

The quickest option to search for a chemical is to enter the chemical name or CASRN (the CAS registry number – a unique identifier for chemical substances) in the “Search IRIS” box on the middle right of the home page. The “Assessments” link under the search bar on the home page allows for more advanced search options.  Using the link, you can browse chemicals alphabetically, by organ or system, and by current stage in the IRIS process. The quick check provides a convenient way of seeing what step of the IRIS process an ongoing chemical assessment is in.  Each chemical in the IRIS database has a chemical-specific webpage, with links to the toxicological reviews (if available), an IRIS summary of the findings, and key information on toxicity values and the organ systems that may be affected by exposure to a chemical.  Toxicological reviews can be lengthy documents though, and the IRIS summary provides a shorter description of the findings for a given chemical.

Anyone can browse the IRIS database or search for a specific chemical assessment, just like the newly added assessment for trimethylbenzenes (TMBs). TMB’s are a group of volatile hydrocarbons produced during petroleum refining and may be inhaled by exposure to vehicle emissions.  The IRIS assessment for TMBs actually contains information on three isomers: 1,2,3-TMB, 1,2,4-TMB, and 1,3,5-TMB, which all have specific chemical pages on the IRIS website.

scrren shot of the specific page within the IRIS website

Whether you’re interested in TMBs or any other chemical, a wealth of information is available on each chemical’s webpage.  The critical systems affected by a chemical are identified, along with toxicity values (like the reference dose and reference concentration for non-cancer effects) and are provided right on the main page.  For example, TMBs are associated with nervous, respiratory, and hematological system effects.  The carcinogenicity of a chemical is also described through a weight-of-evidence characterization, as well as quantitatively, if appropriate.  Each IRIS assessment provides authoritative, peer-reviewed information on a chemical’s toxicity.

A tremendous amount of work goes into completing the 7-step process to finalize a draft IRIS assessment. EPA releases a number of documents along the way, including past drafts of assessments, comments from interagency reviewers, and preliminary materials used early in assessment development.  Your gateway to all this information is through the “History” tab right on the main page for each chemical entry on the database.

IRIS assessments aren’t regulations, but they provide a critical part of the scientific information for decision-making to protect public health across EPA.  They’re also important resources for state environmental and public health agencies, and are widely used by the scientific community in the U.S and the world.

If you have any questions regarding the IRIS Program or the website, you can always contact us at the IRIS hotline at 202-566-1676 or hotline.iris@epa.gov.

About the Authors: Ashley Mayrianne Jones is a student contractor and writer working with the science communication team in EPA’s Office of Research and Development.  Lou D’Amico is the Acting Communications Director for the National Center for Environmental Assessment, which houses the IRIS Program.

Editor's Note: The opinions expressed here are those of the author. They do not reflect EPA policy, endorsement, or action.

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Interconnections in the Web of Life

By Randy Comeleo

For the past five years, we have been composting our food scraps with the assistance of red worms in outdoor bins at EPA’s Western Ecology Division (WED) laboratory in Corvallis, Oregon.  Last winter, we noticed that large food scraps were being stirred-up overnight by something in our compost bins.  We installed a self-operated wildlife camera inside one of the bins and soon identified the culprits: an after-hours party of dusky-footed woodrats–handsome, ash gray packrats with large ears and furred tails–were enjoying the freshly added vegetables.

A night-vision video captures a rat enjoying food from the compost bin

A dusky-footed woodrat visits the EPA Western Ecology Division laboratory compost bins.

Over the next several months, our self-operated wildlife camera revealed a continuous nighttime parade of skunks, raccoons, opossums, gray foxes, and coyotes on our WED campus.

The video captures a fox hanging around the fence of the campus at night

A self-operated wildlife camera captures a photo of a coyote at the EPA Western Ecology Division.

A remarkable example of the interconnectedness of species occurred a few weeks ago when we witnessed a female osprey carrying a large fish over our WED property.  The osprey lost her grip on the fish when she turned into a strong westerly headwind and the fish landed a few feet from the WED gray fox family’s den site.

A bird flying carrying a fish

An osprey carrying a largescale sucker flies over the EPA Western Ecology Division laboratory (Photo by Randy Comeleo).

The next day, we found the partially scavenged fish on the ground and identified it as a largescale sucker, most likely from the Willamette River, located nearly two miles away.

Gray fox pups enjoyed a fresh fish delivery to the EPA Western Ecology Division (photo by Bonnie Smith).

Gray fox pups enjoyed a fresh fish delivery to the EPA Western Ecology Division (photo by Bonnie Smith).

The fish was soon completely consumed by the hungry little foxes and the event illustrated just how interconnected we all are in the Web of Life.

 

About the Author: Randy Comeleo is an Ecologist for EPA’s Western Ecology Division research lab. He works primarily with the Air, Climate, and Energy research program as a Geographic Information System Analyst.

Editor's Note: The opinions expressed here are those of the author. They do not reflect EPA policy, endorsement, or action.

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Research Recap

By Aaron Ferster

research_recap_250Despite the short work week and the return of a mid-summer-like heat wave, EPA researchers were able to continue to get a lot of work done. Here’s a quick recap of some of what we shared this week.

Innovative Science is Bubbling Up

“The way that methane emission rates from reservoirs are currently estimated doesn’t take into account a number of factors that can affect how much is emitted into the atmosphere such as the location, water depth, overall size of the reservoir and other conditions,” writes Rose Keane. Her blog explains how Jake Beaulieu and other EPA researchers are developing new models and tools to fix that, and improve such estimates. Read all about it in her post, Bubbling Up: Methane from Reservoirs Presents Climate Change Challenge.

Climate Change Impact EPA Science

For several EPA researchers, days spent along the coast aren’t just great for their scenic beauty. Such important ecosystems are also important field sites for scientific investigation. Researchers have recently published results of work examining how different impacts of climate change are affecting coastal ecosystems. They demonstrate how vulnerable these natural resources are to drought, sea level rise, and other impacts of a changing climate. Read about them in Andrew Miller’s blog, Climate Change…By the Seashore.

About the Author: EPA science writer Aaron Ferster kept busy this week covering the Research Recap.

Editor's Note: The opinions expressed here are those of the author. They do not reflect EPA policy, endorsement, or action.

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Bubbling Up: Methane from Reservoirs Presents Climate Change Challenge

By Rose Keane

EPA researcher Jake Beaulieu spends a lot of his time on the water, especially at Harsha Lake, a reservoir just southeast of Cincinnati, OH. He’s not a sailor, nor does he work with marine life. Instead, Beaulieu studies how methane (CH4)—a less discussed but more powerful greenhouse gas than carbon dioxide—is emitted from reservoirs. He and other EPA researchers are developing new models and tools to improve methane emission estimates in reservoirs and our understanding of their contributions to greenhouse gas levels globally.

Beaulieu’s team using a new surveying technique to measure methane emissions from reservoirs.

Beaulieu’s team is applying surveying techniques in novel ways to estimate methane emissions.

Methane gas contributes to rising temperatures and one way it is produced is by tiny organisms in sediments at the bottom of lakes. One important source of food for these organisms is decaying algae, which is converted to methane when eaten by these tiny organisms.

According to Beaulieu, the way that methane emission rates from reservoirs are currently estimated doesn’t take into account a number of factors that can affect how much is emitted into the atmosphere such as the location, water depth, overall size of the reservoir and other conditions.

One of the main ways that large amounts of methane are released from reservoirs is through something called ebullition—or more simply, the bubbles that come up from the mud. The bubbles are filled with methane, and Beaulieu’s research has shown that in areas where the water is deeper and less disturbed, there’s less of these methane bubbles coming to the surface. In areas where the water is more shallow or more frequently disturbed, there’s not enough weight (from the atmosphere or from the water itself) to hold the bubbles in, so emissions increase.

In April this year, 177 countries and states across the world signed the Paris Agreement on Climate Change—a landmark agreement that outlines ways for countries to limit their greenhouse gas emissions, encourage more sustainable infrastructure and economic development, and better plan for responding to the impacts of changing climatic conditions. Beaulieu says that improved estimates of methane emissions from reservoirs will result in better information that can aid in the global effort to reduce greenhouse gas emissions.

His paper, Estimates of reservoir methane emissions based on a spatially balanced probabilistic survey, was recently published in Limnology and Oceanography.

About the Author: Rose Keane is an Oak Ridge Associated Universities contractor with the science communications team in EPA’s Office of Research and Development.

Editor's Note: The opinions expressed here are those of the author. They do not reflect EPA policy, endorsement, or action.

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