News
Untreated sewage and fertilizer runoff threaten the Florida manatee’s main food source, contributing to malnutrition
Aarin-Conrad Allen, Florida International University
The gentle, slow-moving Florida manatee has no natural predators.
And yet, these charismatic mammals face numerous threats.
Manatees are struck by vessels in busy waterways across the state, and a majority bear scars from these collisions.
Harmful algal blooms – characterized by the rapid growth of algae that degrades water quality – can impair their nervous systems.
With less blubber, or fat, compared with other marine mammals like whales, dolphins, seals and sea lions, manatees are vulnerable to cold-stress syndrome during winter months.
And they can ingest or get entangled in marine debris like derelict fishing gear and drown or be crushed by floodgate and water control structures.
I am a doctoral candidate in marine biology at Florida International University’s Institute of Environment. Over the past 15 years, I have gained extensive experience working with marine mammals, particularly manatees.
Recently, my colleagues at the United States Geological Survey, Florida Department of Environmental Protection and I documented a change in the dietary pattern of manatees. We found that manatees are eating less seagrass – traditionally their primary food source – and more algae than in decades past. This change occurred along Florida’s Atlantic coast during a period of extensive seagrass decline.
We believe this represents an emerging threat to the species’ survival.
Protected species
Manatees were listed as an endangered species under the Endangered Species Act of 1973. By the early 1990s, the manatee population in Florida had dwindled to less than 1,300.
Researchers believe that federal protection, along with additional state measures such as slow-speed zones and no-entry refuges, has contributed to the growth of the manatee population in Florida.
In 2017, manatees were reclassified from endangered to threatened. Surveyors counted 5,733 individual manatees during a statewide aerial survey conducted in 2019.
Florida manatees average 9-12 feet (2.7-3.7 meters) in length and typically weigh about 1,000 pounds (450 kilograms), but they can grow as large as 3,500 pounds (1,600 kilograms). As the largest fully aquatic herbivore, they consume 5% to 10% of their body weight in vegetation each day.
While manatees eat a broad diet of over 60 different plants, they most commonly feed on species of seagrass. Seagrasses are marine plants that, like land plants, have leaves, flowers, roots and seeds, and make their food through photosynthesis.
So what happens when these seagrasses are no longer available?
A changing estuary
The Indian River Lagoon is an estuary along Florida’s east coast that covers roughly 350 square miles (560 square kilometers) between the mainland and barrier islands, from Ponce Inlet to Jupiter Inlet.
It is a critical habitat for manatees, which feed on native seagrass meadows in the lagoon during their seasonal migrations.
Seagrasses are vital to the health of marine ecosystems. They are a habitat for juvenile fish and other marine organisms, provide food for aquatic herbivores, reduce carbon in the atmosphere and improve water quality. They also protect coastal habitats by stabilizing sediments and reducing wave energy that can erode shorelines and damage coastal infrastructure, especially during hurricanes.
For more than a decade, the Indian River Lagoon has experienced extensive loss of seagrass meadows, due to a series of algae blooms associated with nutrient runoff and degraded water quality from septic overflow leaching into the environment.
When untreated sewage and fertilizers flow into the estuary, they add nitrogen, phosphorus and other nutrients that drive excessive algal growth. These harmful algal blooms deplete oxygen levels and block sunlight, which seagrass needs for photosynthesis.
Between 2011 and 2019, over 50% of all seagrass in the lagoon was lost. This led to an increase in macroalgae and even led to a change in the animal communities that live in the lagoon. For example, among finfish, sheepshead populations declined, while seabream numbers increased. Invertebrate communities were also affected, with bryozoans colonizing areas previously dominated by barnacles.
Manatees along the Atlantic coast have suffered two unusual mortality events since the seagrass decline, including one that is ongoing. Researchers attribute the increase in manatee deaths to malnutrition due to a shortage of seagrasses in the Indian River Lagoon.
A shift in manatees’ diet
In our study, we examined 193 manatee stomach samples collected from carcasses recovered from the Indian River Lagoon during two time periods – one before and one after the onset of the seagrass loss in 2011.
We compared stomach sample contents from carcasses collected between 1977 and 1989 with samples collected between 2013 and 2015.
Our findings indicate that manatees consumed 45% less seagrass and 74% more algae after the seagrass decline.
Recently, in a study supported by FIU’s Center for Aquatic Chemistry and Environment, I investigated differences in the nutritional composition – like protein, fat, carbohydrate and fiber – of items identified in manatee stomach samples. My preliminary results show notable differences in the nutritional composition of seagrass and algae.
Marine mammals are particularly vulnerable to dietary shifts due to their large size and high energy demands. Such changes can worsen their physical health and increase the likelihood of starvation.
Depleted oxygen levels are having a similar impact on aquatic vegetation and seagrass meadows in other regions of Florida, like Biscayne Bay and the Caloosahatchee River and Estuary. This suggests that the ecological challenges seen in the Indian River Lagoon could become more widespread.
What is the solution?
Remediation efforts within the lagoon have incorporated the restoration of seagrass through aquaculture and replanting strategies, similar to efforts to restore coral reefs.
While the lagoon’s seagrass has recently shown signs of regrowth, the rehabilitation of the ecosystem must begin with improving and maintaining water quality.
Counties along the lagoon have enacted fertilizer bans that aim to reduce the levels of nitrogen and phosphorus in the water that drive algal blooms.
New research, however, indicates that these restrictions alone will not fix the problem, as residential septic systems are the primary source of nutrient pollution in the lagoon.
Furthermore, many of the factors contributing to harmful algal blooms are intensified by global warming and changing climate, which could accelerate the decline of seagrass in Florida and elsewhere.
Given the multiple, synergistic threats facing manatees, I believe that improving water quality, protecting their food sources, and further research – coupled with community outreach and education – are critical to ensure the long-term survival of this iconic Florida species.
Aarin-Conrad Allen, Ph.D. Candidate in Marine Sciences, Florida International University
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
