News
When your local reflecting pool or pond turns green with algae, don’t reach for chemicals – nature has better solutions
When ponds and reflecting pools turn green with algae, chemical “quick fixes” often fail. Here’s how nature-based solutions like Daphnia and aquatic plants can restore water quality longer-term.
Eric Palkovacs, University of California, Santa Cruz
When the Lincoln Memorial Reflecting Pool turned green with algae just days after a US$15 million renovation, the U.S. government scrambled for chemicals and expensive technical solutions to fix the iconic landmark.
Trying to kill algae with chemicals is a common response when community ponds or other water features go green. But as a scientist who studies freshwater ecology, I can tell you there are better solutions that cost far less, last longer and carry less risk of harm to pets and wildlife.
Rather than battling against nature, these alternatives work with nature for long-term solutions. https://www.youtube.com/embed/nkqBQ1r0Kto?wmode=transparent&start=0 If you need to treat a slimy, green, algae-filled body of water, you shouldn’t drain and refill the water, which resets the entire ecosystem. Instead, one solution is quite simple and relies on nature, not chemicals.
What went wrong on the National Mall
The algal bloom that turned the Reflecting Pool a vibrant green shouldn’t have been a surprise.
The pool is big, more than a third of a mile long and around 165 feet wide. But it’s shallow, meaning it warms up quickly in the sun. When it was repainted “American flag blue” during the renovations in spring 2026, the new color darkened the pool, and darker colors absorb more heat.
On top of those conditions, the pool was refilled with water from the nutrient-rich tidal basin of the Potomac River. The combination of warm water and nutrients created prime conditions for algae to bloom, turning the water pea soup green.
As the national conversation over the Reflecting Pool shifts to political finger-pointing, an important environmental question deserves careful scrutiny: What is the best approach to maintain water quality in a case like this, whether for a national monument or a community water feature or pond?
Trying to chemically or mechanically remove algae can damage the structure of a water feature and may harm species in the water that could actually help solve the problem.
Importantly, chemical and mechanical solutions are only temporary fixes. When the Reflecting Pool is drained and filled again, there’s a good chance that algae will bloom again.
Natural algae control
Limnologists – scientists like me who study inland water bodies – have spent many decades learning why lakes and ponds turn green and how to clear them up.
Often, nutrient-rich waters fueled by fertilizer runoff from farm fields or sewage from cities are the sources that stimulate algal growth.
However, natural ponds also host grazing zooplankton, which eat algae. For example, a type of zooplankton called Daphnia, known as water fleas because of the way these tiny crustaceans swim, can control algae by consuming it before it becomes a pea soup nuisance. Thus, a thriving Daphnia population can help maintain good water quality in a lake, pond or community water feature, even when nutrient levels spike.
In addition to being highly effective grazers, Daphnia have another superpower – they can evolve rapidly. Urban waterbodies are often harsh environments with a variety of challenges, including high temperatures, low levels of dissolved oxygen, and pollutants. Daphnia can adapt to tough conditions, making these creatures an ideal source of algae control in many urban ponds.
Rooted aquatic plants are also useful for algae control in ponds because they absorb nutrients. Thus, shallow ponds with thick beds of aquatic plants can often resist algal blooms when nutrient levels rise.
Why draining might not be the best solution
One downside to draining and refilling a pond or urban water feature to try to clean it is that doing so resets the aquatic ecosystem, erasing the signature of any past evolution that has taken place.
Imagine Daphnia in a shallow pond that experiences periodic heat waves throughout the summer. Through repeated exposure to high temperatures, natural selection favors heat-resistant genotypes that can thrive in an urban pond.
Daphnia and other grazing zooplankton can also evolve resistance to some types of cyanobacteria, also known as blue-green algae, which produce compounds that are toxic to people and pets. Daphnia that evolve resistance to those toxins can help control harmful cyanobacterial blooms.
If a Daphnia population that evolved to tolerate warm temperatures, low oxygen levels or cyanotoxins is removed, the new population likely won’t be ready to handle those local challenges. This evolutionarily naive population will perform poorly in its new environment, reducing its effectiveness at controlling algal blooms.
As a result, traditional mechanical and chemical approaches may actually work against the goal of minimizing algae in ponds and other water features.
Nature-based solutions
The use of Daphnia to control algal blooms is just one example of solving environmental challenges with nature-based solutions.
Growing urban forests to provide cooling and improve air quality to help reduce the need for more energy-intensive air conditioning is another example. Maintaining urban wetlands can help reduce flooding, protect property and recharge groundwater more effectively and for less money than building and maintaining levees. Coastal marshes similarly reduce erosion, buffer storm surges and support fisheries.
All these urban ecosystems protect biodiversity and support human health and well-being.
From national landmarks to city parks and backyard ponds, projects of all sizes can take advantage of nature-based solutions. While each specific project is unique, some general principles apply.
Ecosystems are most resilient when they are diverse and connected. So, it is beneficial to use a variety of species and genotypes and provide corridors that support the movement of organisms and their beneficial genes.
Urban climates are changing rapidly, so it helps to use species and genotypes that will thrive under future conditions, including rising temperatures.
Not every solution has to be engineered
The hubbub over the Reflecting Pool holds a mirror up to assumptions about how to solve pressing environmental challenges. The idea of just engineering one’s way out of any environmental crisis has limits.
Understanding ecology and nature’s mechanisms of ecosystem resilience can achieve sustainable solutions that benefit both nature and people.
Eric Palkovacs, Professor of Ecology and Evolutionary Biology, University of California, Santa Cruz
This article is republished from The Conversation under a Creative Commons license. Read the original article.
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Food Truths
The Truth About the “Chemical” in McDonald’s Burger Buns: Should Consumers Be Concerned?
What’s in the Burger Buns:The “yoga mat chemical” controversy changed how consumers view food additives. Here’s what azodicarbonamide is, why McDonald’s removed it, and what the science actually says.
For years, headlines and social media posts have warned consumers about a so-called “yoga mat chemical” found in hamburger buns served by major fast-food chains. The claims sparked widespread concern, prompted petitions, and eventually led several restaurant companies—including McDonald’s—to change their recipes.
But what was the chemical, and is there actually a health risk today?
What Was the Controversial Ingredient?
The ingredient at the center of the controversy was azodicarbonamide (ADA), a chemical used as a dough conditioner. It helped improve the texture of bread, making dough easier to handle and producing softer, more consistent buns.
Ironically, the same compound is also used in manufacturing certain foamed plastics, including some yoga mats and shoe soles. That connection gave rise to the viral nickname, “the yoga mat chemical.”
While the comparison was technically accurate, it also lacked important context. Food-grade azodicarbonamide and industrial applications are very different, and many chemicals have multiple uses across industries.
Why Did People Become Concerned?
The concern wasn’t simply that ADA was used in food. Scientists focused on what happens during baking.
When bread is baked, most azodicarbonamide breaks down into other compounds. Some laboratory studies involving animals raised questions about one of these breakdown products, called semicarbazide (SEM), when administered in high doses.
Those findings prompted some countries to take a more cautious regulatory approach.
Why Is It Banned in Some Countries?
The European Union and Canada do not permit azodicarbonamide as a flour treatment agent. Their food safety policies often follow the precautionary principle, removing ingredients when safer alternatives exist or when scientific uncertainty remains.
In contrast, the U.S. Food and Drug Administration has determined that azodicarbonamide is safe when used within approved limits.
These differing regulations don’t necessarily mean one side believes the ingredient is dangerous while the other believes it is harmless. Instead, they reflect different philosophies about regulating food additives.
Does McDonald’s Still Use It?
No.
McDonald’s removed azodicarbonamide from its U.S. hamburger buns in 2014 following growing consumer demand for simpler ingredient lists.
Today’s buns no longer contain the ingredient, joining a broader trend among food manufacturers to eliminate additives that have become controversial with consumers.
Are There Other Ingredients Consumers Should Know About?
Modern commercial bread still contains ingredients designed to improve freshness, texture, and shelf life.
These may include:
- Calcium propionate to prevent mold
- Ascorbic acid (Vitamin C) as a dough conditioner
- Enzymes that improve consistency
- Emulsifiers that help maintain softness
These ingredients have been evaluated by food safety agencies and are generally recognized as safe when used according to regulations.
The Bigger Health Picture
Nutrition experts generally agree that focusing on one ingredient can distract from the larger issue.
The greatest health risks associated with fast food are more closely linked to:
- High sodium intake
- Excess saturated fat
- Added sugars
- Large portion sizes
- Frequent consumption of ultra-processed foods
An occasional fast-food meal is unlikely to determine someone’s long-term health. Overall dietary patterns, physical activity, sleep, and other lifestyle factors have a much greater impact.
Consumer Awareness Is Changing the Food Industry
Whether or not an ingredient poses a measurable health risk, public concern can influence corporate decisions.
Over the past decade, many food companies have reformulated products to remove controversial ingredients, reduce artificial additives, and simplify ingredient labels. In many cases, those changes have been driven as much by consumer preferences as by regulatory requirements.
The Bottom Line
The “yoga mat chemical” story captured public attention because it combined science, food safety, and memorable marketing. While azodicarbonamide was once used in some hamburger buns, including those supplied to McDonald’s, the company removed it from its U.S. buns years ago.
Current evidence suggests consumers are better served by paying attention to their overall diet rather than worrying about a single ingredient that has already disappeared from many products.
Being an informed consumer means looking beyond the headlines, understanding the science, and recognizing that nutrition is about the complete picture—not just one ingredient.
Related External Links
- U.S. FDA – Food Additives & GRAS Ingredients Information for Consumers
- U.S. FDA – Food Additives and Petitions
- FDA – Azodicarbonamide (ADA) Food Substance Database
- Electronic Code of Federal Regulations – 21 CFR §172.806 (Azodicarbonamide)
- FDA – Types of Food Ingredients and Why They’re Used
- Health Canada – Permitted Flour Treatment Agents
- McDonald’s USA – Nutrition Calculator & Ingredient Information
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STM Blog
Association of Black Cardiologists to Celebrate Legacy and Leadership at 16th Annual Spirit of the Heart Awards
The Association of Black Cardiologists (ABC) is bringing its signature celebration of impact back to New York City this fall—spotlighting leaders and organizations working to make cardiovascular care more equitable, more accessible, and more effective. The 16th Annual Spirit of the Heart Awards Program & Fundraiser is set for Saturday, October 3, 2026 (6:00 p.m.–9:00 p.m.) at Cipriani Wall Street in Manhattan.
For ABC, the evening is more than a high-profile awards program. It’s a cornerstone fundraising event that helps power the organization’s year-round work—supporting medical student scholarships, fellowships, education, and programs designed to strengthen the pipeline of diverse clinicians and researchers while improving outcomes in communities that carry a disproportionate burden of heart disease.
A fundraising night with long-term stakes
ABC leaders say the Spirit of the Heart Awards is built around a simple idea: celebrating progress while investing in the people who will drive the next wave of change.
Event co-chair Icilma Fergus, MD—Director of the Cardiovascular Disparities Center at Mount Sinai Medical Center and Board Chair of ABC—framed the night as a forward-looking commitment.
“This gathering is about more than one evening of celebration; it is about investing in the future of cardiovascular health for years to come,” Fergus said in the announcement. She added that the support generated through the event helps expand opportunities for aspiring clinicians, researchers, and leaders whose work can transform care and improve lives nationwide.
Honorary Chairperson: Samin K. Sharma, MD
ABC announced Samin K. Sharma, MD as the event’s Honorary Chairperson. Sharma serves as Chief of Clinical Cardiology, Director of the Cardiovascular Clinical Institute, and the Anandi Lal Sharma Professor of Medicine at the Icahn School of Medicine at Mount Sinai.
In the release, ABC highlighted Sharma’s international reputation in interventional cardiology and physician education, noting that he has trained cardiovascular specialists from around the world while advancing the field through research, mentorship, and patient care.
“I am honored to serve as Honorary Chairperson for this important event,” Sharma said. “The Spirit of the Heart Awards Program reflects the power of partnership, philanthropy, and leadership to advance cardiovascular health.”
A full weekend of impact, including policy
The awards program is part of a broader weekend of programming. On Friday, October 2, ABC will host its Annual Policy Pulse Summit at Venable LLP in New York City, convening leaders to discuss policy issues shaping the future of cardiovascular health.
What to expect at the Spirit of the Heart Awards
ABC is positioning the evening as both a celebration and a community gathering—bringing together leaders from healthcare, philanthropy, industry, and advocacy.
The event will be co-emceed by:
- Sandra Bookman, award-winning journalist and anchor of Eyewitness News on ABC7/WABC-TV New York
- Thomas Cunningham IV, President and Chief Content Officer of BrandCunningham
The program is expected to include:
- Presentation of the Spirit of the Heart Awards
- Recognition of medical student scholarship recipients
- Special guest appearances
- A live auction
- Musical entertainment
Event co-chair Barbara Hutchinson, MD, PhD, President of Chesapeake Cardiac Care, emphasized the role of sustained collaboration in moving the needle on heart health.
“The Spirit of the Heart Awards Program is a reminder that lasting progress in cardiovascular health is achieved through vision, partnership, and sustained commitment,” Hutchinson said.
How to attend, sponsor, or support
ABC is directing attendees and supporters to its event site for tickets, sponsorship opportunities, and donations:
- Event info / tickets / sponsorship / donations: https://abcardioevents.org
About the Association of Black Cardiologists
Founded on the belief that “every heart counts,” the Association of Black Cardiologists works to promote prevention and treatment of cardiovascular disease and to advance health equity by eliminating disparities. ABC’s membership is open to all, regardless of race, ethnicity, or vocation. The organization’s work spans education, advocacy, research, patient and community outreach, and leadership development.
- Organization website: https://abcardio.org
Source and media contact
- Press release source (PRNewswire): https://www.prnewswire.com/news-releases/association-of-black-cardiologists-to-celebrate-legacy-and-leadership-at-16th-annual-spirit-of-the-heart-awards-302206000.html
Media Contact (from the release):
- Akeia Blue, VP of Communications
- 419395@email4pr.com
- 240-321-9227
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Food and Beverage
Millions of Eggs Recalled Over Possible Salmonella Risk: What Consumers Need to Know
A major egg recall is affecting nearly 1.6 million dozen eggs sold under several popular brands. Here’s how to determine if your eggs are included and what steps to take if they are.
News You Can Use This Moment!
Consumers are being urged to check their refrigerators after a major recall involving nearly 1.6 million dozen shell eggs due to the potential presence of Salmonella Enteritidis, a bacterium that can cause serious foodborne illness.
The voluntary recall, announced by Midwest Poultry Services, L.P., affects white shell eggs and brown cage-free eggs produced at two Texas farms and distributed between June 6 and July 3, 2026. According to the U.S. Food and Drug Administration (FDA), the eggs were sold through grocery stores and foodservice distributors in Texas, Louisiana, Oklahoma, Arkansas, Mississippi, and New Mexico.
What Brands Are Included?
The recalled eggs were sold under several familiar brand names, including:
- Kroger
- Simple Truth
- Brookshire’s
- Country Morning
- Sunups
Not every carton under these brands is affected. Consumers should look for:
- Plant Code: P-1950 or 0840962
- Julian Dates: 157 through 184
- Best By/Sell By Dates: July 20, 2026, through August 17, 2026
Why the Recall Matters
Salmonella can cause symptoms including:
- Diarrhea
- Fever
- Stomach cramps
- Nausea
- Vomiting
Symptoms typically begin 12 to 72 hours after eating contaminated food and usually last four to seven days. While many healthy adults recover without treatment, infections can become severe in young children, older adults, pregnant women, and people with weakened immune systems.
The FDA and the Centers for Disease Control and Prevention (CDC) are investigating a multistate outbreak involving 98 confirmed illnesses across 17 states, resulting in 26 hospitalizations. No deaths have been reported. Investigators say the recalled eggs are linked to part of the outbreak, although they do not account for every reported illness.
What Should You Do?
If you have eggs matching the recalled codes:
- Do not eat them.
- Return them to the store for a refund or dispose of them safely.
- Wash your hands thoroughly after handling the carton.
- Clean and sanitize any refrigerator shelves, containers, or kitchen surfaces the eggs may have touched.
If you have already eaten the eggs and develop symptoms of Salmonella infection, contact your healthcare provider, especially if symptoms are severe or persist.
Are Arizona Consumers Affected?
The recalled products were officially distributed in six states, and Arizona is not listed among the primary distribution states. However, because food products can move through wholesalers, travelers, or secondary retailers, Arizona consumers who recently purchased eggs while traveling—or who received eggs from family or friends in affected states—should still check the carton codes.
The Bottom Line
Food recalls are an important part of protecting public health. Taking a few moments to inspect the eggs in your refrigerator could help prevent a serious illness. If your carton matches the recalled plant codes and date range, don’t take the risk—return it or throw it away.
STM Daily News will continue to monitor this developing story and provide updates as additional information becomes available.
Related Resources
- FDA Recalls, Market Withdrawals & Safety Alerts
- FDA Foodborne Illness Outbreak Investigations
- CDC: Salmonella Information
- FoodSafety.gov Consumer Resources
