Scientists find ‘alarming' levels of toxic metals, pollution in Lake Maurepas
Scientists at Southeastern Louisiana University have found dangerously high levels of toxic metals and other contaminants in Lake Maurepas and have traced most of the pollution to industrial and other human activities.
Led by SLU chemistry professor Fereshteh Emami, a team of researchers analyzed 400 water and sediment samples collected from multiple locations and depths in the lake from June through December 2023 and developed new methodologies to trace the origin of the pollutants, track how they spread and determine the factors that make them worse. The results were 'alarming,' according to the study, which was published in Environments in November and accepted for publication in another scientific journal, ACS Omega, this month.
The analysis revealed concentrations of heavy metals and nutrients far beyond the thresholds the Environmental Protection Agency considers safe. Arsenic levels peaked at 420% above the safe limit for lakes and 6,300% over the EPA's drinking water threshold. Lead and cadmium were detected at similarly high levels averaging orders of magnitude above safe limits. Nickel, copper, and manganese concentrations were also observed above their respective safety thresholds.
Heavy metal exposure is known to cause severe health problems and can be fatal to humans.
'I was just surprised how polluted the area is,' Emami said in an interview.
Emami's team at Southeastern developed new methodologies that allowed them to trace the pollutants to Pass Manchac and three rivers that feed into Lake Maurepas: the Blind, Amite and Tickfaw. It indicated that industrial and agricultural activities are major sources of the pollution.
The researchers also detected a spike in contaminants near Pass Manchac following the Oct. 23, 2023, 'super-fog' multi-vehicle pileup on Interstate 55, indicating that toxic chemicals from combustion vehicles are also running off into the lake.
The heavy metal concentrations found in Lake Maurepas are similar to those later detected following breaks in the waste containment levees at the Atlantic Alumina (Atalco) facility in Gramercy last year. Atalco's toxic metals — which also included arsenic, cadmium and lead, among others — ended up in a public drainage system that flows into the Blind River Swamp of Lake Maurepas.
Although Emami's new methodologies did not trace the pollutants to specific facilities, news of the Atalco incident brought to light a previously unknown event that aligns with their findings, at least anecdotally, Emami said. More sampling and analysis is needed deeper upstream into those rivers in order to further narrow down the sources, she said.
The researchers found other contaminants in the lake, including high levels of nitrogen, phosphorus and a parameter called chemical oxygen demand, which indicates the presence of organic pollutants in water. According to the study, all three parameters were elevated at averages beyond what is considered safe. Their methodologies traced these pollutants to urban runoff and agriculture.
The samples contained other toxic metals, such as mercury, at levels that were within safe limits. But the study noted they still pose a threat to humans and the environment through bioaccumulation, in which low doses of a heavy metal can amass in a living organism over time and add up to a dangerous level.
'Because of the non-biodegradable and bioaccumulative nature of these heavy metals, they could accumulate and biomagnify in fish and other aquatic animals,' the researchers wrote. 'As a result, they could enter the human body eventually through the food chain.'
Emami said mercury is particularly dangerous because it easily bioaccumulates in crops and animals such as fish. Her team is conducting a follow-up study in which they are testing aquatic samples from Lake Maurepas and surrounding rivers for heavy metals and other contaminants such as polyfluoroalkyl substances (PFAS), known as 'forever chemicals.'
Corinne Gibb, a chemist who works for the environmental advocacy Louisiana Bucket Brigade and was not involved in the study, said the research very clearly points to pollution that is flowing into Lake Maurepas from other water bodies.
'What they're showing for sure is that the pollution is coming through those rivers,' Gibb said.
A Louisiana refinery spilled toxic waste into the community and knew about it for months
Southeastern has been monitoring Lake Maurepas since the proposal of a carbon sequestration project by Air Products & Chemicals. The company plans to use carbon capture technology to trap emissions from an $8 billion hydrogen manufacturing complex in Ascension Parish and take them by pipeline to Lake Maurepas, where Air Products will have the capacity to inject an estimated 5 million tons of CO2 per year about a mile below the lakebed.
In the first half of 2023, Air Products performed seismic testing to map the geological formations under the lake. In August of that year, the company moved a large temporary drilling rig into Lake Maurepas that served as a test well for the collection of core and fluid data, which ended in early 2024.
Emami's team initially suspected but were ultimately unable to link any chemical pollutants to Air Products' activity in the lake. Aside from providing a multi-million dollar funding grant, the company played no role in any aspects of the study, its design or the decision to publish the results.
'We're committed to protecting the Lake Maurepas environment and ecosystem, which is why we have supported the independent monitoring of the Lake,' Air Products spokeswoman Christina Stephens said Wednesday after learning about the SLU study's findings. 'It's important for people to understand the lake's ecosystem, and as our work progresses we will continue to operate in a safe and responsible fashion.'
That still doesn't assuage concerns of some local lawmakers. Rep. Kim Coates, R-Ponchatoula, who ran for office on a platform of protecting Lake Maurepas, pointed out the study shows the baseline water quality of the lake is already deeply concerning and could be made worse with general disturbances that accompany lakebed drilling and similar industrial activities.
'Adding deep geological carbon sequestration to an ecosystem already under strain from nutrient pollution raises serious questions,' Coates said. 'Even well-intentioned projects can have unintended consequences in such a delicate and dynamic environment. Until more is known, extreme caution is not just warranted — it's essential.'
SLU's study is the first of its kind to combine dynamic statistical models with water quality data to trace pollutant sources and their driving factors. This allowed Emami's team to provide a comprehensive assessment of the chemical composition of Lake Maurepas based on a wide array of data. The methodology can also be used to predict when and where pollutants will flow or migrate to other areas, she said.
'Using the models, we were looking for the origins of the pollutant sources, and I wanted to know if the pollution sources in the Blind River could [let us] predict what was gonna show up in Manchac,' Emami said. 'And it did.'
Emami said Pass Manchac's significant tidal exchange between Lake Maurepas and Lake Pontchartrain has allowed her team to conclude that the water quality and levels of pollution between the two estuaries are virtually the same.
Until the start of Southeastern's research, there was no ongoing public monitoring for toxic metals in Lake Maurepas.
Louisiana Department of Environmental Quality spokesman Matthew Day said the public should be aware of existing fish consumption advisories, such as one issued last year for Lake Maurepas based on elevated mercury levels detected in fish tissue. However, the agency does not conduct any regular heavy metal monitoring in Lake Maurepas because it is not required under Clean Water Act obligations, Day said.
SUPPORT: YOU MAKE OUR WORK POSSIBLE
Hashtags
Try Our AI Features
Explore what Daily8 AI can do for you:
Comments
No comments yet...
Related Articles
Medscape
20 minutes ago
- Medscape
Calcium Deposition Can Increase Osteoarthritis Risk
Calcium crystal deposition may be a risk factor for knee osteoarthritis (OA), according to a new study. In an analysis including more than 6400 middle-aged to older adults, individuals with knee chondrocalcinosis were 75% more likely to develop knee OA than those without the condition at baseline. Because knee chondrocalcinosis and OA are often observed together, it is commonly considered a feature of the OA disease process, said Jean W. Liew, MD, an assistant professor of rheumatology at Boston University, Boston, and coauthor of the study. 'This study suggests that calcium crystal deposition is a cause of knee OA rather than just a consequence,' she told Medscape Medical News . The analysis included data from two independent cohorts: the Rotterdam Study (RS) and the Multicenter Osteoarthritis Study (MOST). RS enrolled individuals aged 55 years or older residing in Rotterdam, the Netherlands. MOST, which recruited participants from Birmingham, Alabama, and Iowa City, Iowa, enrolled adults aged 50-79 years with preexisting knee OA or at increased risk for OA due to overweight status, knee injury, or knee symptoms. Researchers examined the association between baseline knee chondrocalcinosis, measured via x-ray, and development of radiographic knee OA over time. Radiographic knee OA was defined as a Kellgren and Lawrence grade (KLG) ≥ 2 or if the individual had undergone knee replacement at follow-up. The analysis, published online on August 5, 2025, in Annals of the Rheumatic Diseases , included 3737 individuals from the RS cohort and 2750 individuals from the MOST cohort. At baseline in the RS cohort, 76.1% of participants had no signs of radiographic knee OA (KLG = 0), and 4.3% had knee chondrocalcinosis. For the MOST cohort, 68.5% had no signs of radiographic knee OA, and 5.0% had knee chondrocalcinosis at baseline. The analysis found that knee chondrocalcinosis increased the risk for incident radiographic knee OA after adjustment for age, sex, and BMI. The pooled odds ratio (OR) between both groups was 1.75 (95% CI, 1.25-2.27; P < .001). There were no cases of regression of chondrocalcinosis during follow-up, which suggests that chondrocalcinosis does not resolve over time, Liew and colleagues wrote. In a subgroup analysis including only individuals with KLG of 0 at baseline, the results were similar (OR = 1.77; 95% CI, 1.04-3.01; P = .035). More severe chondrocalcinosis was also associated with increased risk of developing knee OA. Commenting on the study for Medscape Medical News , Sara Tedeschi, MD, MPH, noted that these findings 'strongly suggest that [chondrocalcinosis] is a risk factor for the new development of osteoarthritis in people who don't currently have radiographic osteoarthritis.' Tedeschi is the head of crystal-induced arthritic diseases at Brigham and Women's Hospital in Boston. 'One of the unique features of this paper,' she said, 'is that they were able to look at knees that had chondrocalcinosis at baseline but no osteoarthritis at baseline and were able to follow them forward' with years of follow-up data. Treatment Options Liew now wants to explore whether treatments for inflammation related to calcium crystal deposition could also help prevent or delay progression of OA in this subset of patients. 'It's time to look at designing studies focused on this subgroup of people (with chondrocalcinosis on imaging) and testing whether treatments that work for crystal-associated arthritis like gout or calcium pyrophosphate deposition disease would also work for knee OA,' she said. 'Hints of such benefits have appeared in previous cardiovascular randomized controlled trials of colchicine, where patients receiving the drug had a lower risk of joint replacement as a secondary outcome,' noted Tedeschi. It's 'one interesting therapy to consider' for potential future trials, as are other anti-inflammatory medications like interleukin-1 inhibitors, she added.
Fast Company
an hour ago
- Fast Company
How tech pinpoints urban heat islands and makes cooling projects easier
It's summer, and it's been hot, even in northern cities such as Boston. But not everyone is hit with the heat in the same way, even within the same neighborhood. Take two streets in Boston at 4:30 p.m. on a recent day, as an example. Standing in the sun on Lewis Place, the temperature was 94 degrees Fahrenheit (34.6 degrees Celsius). On Dudley Common, it was 103 F. Both streets were hot, but the temperature on one was much more dangerous for people's health and well-being. The kicker is that those two streets are only a few blocks apart. The difference epitomizes the urban heat island effect, created as pavement and buildings absorb and trap heat, making some parts of the city hotter. A closer look at the two streets shows some key differences: Dudley Common is public open space sandwiched between two thoroughfares that create a wide expanse of pavement lined with storefronts. There aren't many trees to be found. Lewis Place is a residential cul-de-sac with two-story homes accompanied by lots of trees. This comparison of two places within a few minutes' walk of each other puts the urban heat island effect under a microscope. It also shows the limits of today's strategies for managing and responding to heat and its effects on public health, which are generally attuned to neighborhood or citywide conditions. Even within the same neighborhood, some places are much hotter than others owing to their design and infrastructure. You could think of these as urban heat islets in the broader landscape of a community. Sensing urban heat islets Emerging technologies are making it easier to find urban heat islets, opening the door to new strategies for improving health in our communities. While the idea of reducing heat across an entire city or neighborhood is daunting, targeting specific blocks that need assistance the most can be faster and a much more efficient use of resources. Doing that starts with making urban heat islets visible. In Boston, I'm part of a team that has installed more than three dozen sensors across the Roxbury neighborhood to measure temperature every minute for a better picture of the community's heat risks, and we're in the process of installing 25 more. The Common SENSES project is a collaboration of community-based organizations, including the Dudley Street Neighborhood Initiative and Project Right Inc.; university researchers like me who are affiliated with Northeastern University's Boston Area Research Initiative; and Boston city officials. It was created to pursue data-driven, community-led solutions for improving the local environment. Data from those sensors generate a real-time map of the conditions in the neighborhood, from urban heat islets like Dudley Common to cooler urban oases, such as Lewis Place. These technologies are becoming increasingly affordable and are being deployed in communities around the world to pinpoint heat risks, including Miami, Baltimore, Singapore, and Barcelona. There are also alternatives when long-term installations prove too expensive, such as the U.S.'s National Oceanic and Atmospheric Administration volunteer science campaign, which has used mobile sensors to generate onetime heat maps for more than 50 cities. Making cooler communities, block by block Although detailed knowledge of urban heat islets is becoming more available, we have barely scratched the surface of how they can be used to enhance people's health and well-being. The sources of urban heat islets are rooted in development—more buildings, more pavement, and fewer trees result in hotter spaces. Many projects using community-based sensors aspire to use the data to counteract these effects by identifying places where it would be most helpful to plant trees for shade or install cool roofs or cool pavement that reflect the heat. However, these current efforts do not fully capitalize on the precision of sensors. For example, Los Angeles's massive investment in cool pavement has focused on the city broadly rather than overheated neighborhoods. New York City's tree planting efforts in some areas failed to anticipate where trees could be successfully planted. Most other efforts compare neighborhood to neighborhood, as if every street within a neighborhood experiences the same temperature. London, for example, uses satellite data to locate heat islands, but the resolution isn't precise enough to see differences block by block. In contrast, data pinpointing the highest-risk areas enables urban planners to strategically place small pocket parks, cool roofs, and street trees to help cool the hottest spaces. Cities could incentivize or require developers to incorporate greenery into their plans to mitigate existing urban heat islets or prevent new ones. These targeted interventions are cost-effective and have the greatest potential to help the most people. But this could go further by using the data to create more sophisticated alert systems. For example, the National Weather Service's Boston office released a heat advisory for July 25, 2025, the day I measured the heat in Dudley Common and Lewis Place, but the advisory showed nearly the entirety of the state of Massachusetts at the same warning level. What if warnings were more locally precise? On certain days, some streets cross a crucial threshold—say, 90 F—whereas others do not. Sensor data capturing these hyperlocal variations could be communicated directly to residents or through local organizations. Advisories could share maps of the hottest streets or suggest cool paths through neighborhoods. There is increasing evidence of urban heat islets in many urban communities and even suburban ones. With data showing these hyperlocal risks, policymakers and project coordinators can collaborate with communities to help address areas that many community members know from experience tend to be much hotter than surrounding areas in summer. As one of my colleagues, Nicole Flynt of Project Right Inc., likes to say, 'Data + Stories = Truth.' If communities act upon both the temperature data and the stories their residents share, they can help their residents keep cool—because it's hot out there.
Medscape
an hour ago
- Medscape
Pediatric Sleep Screener Boosts Diagnoses, Referrals
Children's poor sleep is associated with obesity, academic problems, suicide attempts, and other mental health concerns, but the issue is not consistently addressed in pediatric primary care. A new well-child-visit screening tool for primary care clinicians (PCCs) appears to help boost diagnosis and referrals, according to findings from a study published in JAMA Network Open . Ariel A. Williamson, PhD, with The Ballmer Institute for Children's Behavioral Health, University of Oregon, Portland, Oregon, and colleagues tested an electronic, age-based sleep screener that evaluated infant bed sharing, snoring three nights a week, short sleep time, perceived sleep problems, and adolescent daytime sleepiness. The researchers conducted a retrospective, observational case-control study in the Children's Hospital of Pennsylvania primary care network of 31 practices in Pennsylvania and New Jersey; 27 in suburban/rural settings and four in metropolitan settings. During implementation, 204,872 patients completed the screening, with adoption in 89.5% of all well-child visits. The screening indicated that 9.7% of patients had frequent snoring, 12.2% had sleep problems, and 34.4% had insufficient sleep. Bed sharing was reported for 6.5% of infants and 14.7% of adolescents reported daytime sleepiness. The identification of sleep problems was followed by provision of family education resources. Sleep Disorder Diagnosis 64% More Likely With Screener Compared with the pre-implementation period, at well-child visits with a completed sleep screener, PCCs were significantly more likely to make a sleep disorder diagnosis (odds ratio [OR], 1.64; 95% CI, 1.56-1.73), order a polysomnogram (OR, 2.67; 95% CI, 2.32-3.20), and refer to sleep clinics (OR, 6.48; 95% CI, 5.03-8.34) or otolaryngology (OR, 4.46; 95% CI, 3.95-5.02). Rupali Drewek, MD, a pediatric pulmonologist and co-medical director of the Sleep Medicine Program at Phoenix Children's in Phoenix, who was not involved with the study, told Medscape Medical News the screener is promising and its proactive approach — even in children with no obvious symptoms — allows for earlier intervention and improved quality of life. 'Sleep problems affect up to half of children at some point,' she said, 'yet they are rarely addressed unless parents bring them up. Implementing a standardized screening tool during routine pediatric visits ensures systematic identification of issues that might otherwise go unnoticed. Taking action early can lead to better health, better school performance, and less stress for families and the healthcare system.' Adding a new screening tool should fit easily into a regular checkup without slowing workflow substantially, she said. 'It offers a scalable, low‑cost solution to reach millions of children.' Educating the medical team will be important to successful implementation, she said. 'Everyone on the care team needs to know how to read the results and what to do next if a child's answers show there might be a sleep problem.' Lessening Healthcare Inequities In an accompanying editorial, Sarah M. Honaker, PhD, with the Department of Pediatrics at Indiana University School of Medicine, Indianapolis, and Stephen M. Downs, MD, MS, with the Department of Pediatrics, Wake Forest University in Winston Salem, North Carolina, said the screener, 'offers a refreshing departure from this pattern of asking PCCs to know more and do more. [T]his is an opportune time to study the implementation of systems that will support PCCs in providing evidence-based care.' The editorialists wrote that the broad screening at well-child visits could help lessen healthcare inequities. They noted that children from minoritized backgrounds with a lower socioeconomic status are more likely, for instance, to have obstructive sleep apnea (OSA) and are less likely to receive timely, evidence-based care. 'For example, Black children are two to four times more likely to have OSA and less likely to receive a [polysomnogram] referral,' they wrote. One of the main unanswered questions, Honaker and Downs wrote, is how much the educational components help once the problems have been identified and whether guidance about sleep duration results in actual improvements in sleep duration. A key strength of the work is replicability in other health systems, with individual adaptations, the editorialists noted. '[T]he system designed by Williamson and colleagues offers an excellent starting point for other healthcare systems seeking to support PCCs in prevention, identification, and management of pediatric sleep disruption,' they wrote. Williamson reported receiving honoraria from the National Sleep Foundation, the American Academy of Pediatrics, and Wesleyan University and an honorarium and travel support from The Pennsylvania State University, outside the submitted work. This study was supported by the Possibilities Project at Children's Hospital of Philadelphia and the Eunice Kennedy Shriver National Institute of Child Health and Human Development. Honaker reported receiving consulting fees from Covington LLC; grants from the National Heart, Lung, and Blood Institute; equity ownership of For Dreamers LLC; and grants from the American Academy of Sleep Medicine Foundation outside the submitted work. Downs reported that he is the co-creator of the Child Health Improvement through Computer Automation (CHICA) software and cofounder of Digital Health Solutions LLC, which licenses CHICA. Drewek reported no relevant financial relationships.
