Coal ash selenium found in fish in N.C. lakes

February 07, 2017

DURHAM, N.C. -- A new Duke University study has found high levels of selenium in fish in three North Carolina lakes receiving power plants' coal ash waste.

"Across the board, we're seeing elevated selenium levels in fish from lakes affected by coal combustion residual effluents," said Jessica Brandt, a doctoral student in environmental health at Duke's Nicholas School of the Environment, who led the study.

Selenium is a naturally occurring element that is concentrated in coal ash and other coal combustion residuals. Early life exposure can cause deformities, impaired growth and reproduction, and in extreme cases death in fish and aquatic invertebrates. Because selenium accumulates in the food chain, it also can be toxic to birds that eat aquatic animals containing high levels.

Brandt and her colleagues published their peer-reviewed study Feb. 6 in the journal Environmental Science & Technology.

They measured selenium levels in surface water, bottom-sediment waters and fish from three N.C. lakes -- Sutton Lake near Wilmington, Mayo Lake near Roxboro, and Mountain Island Lake near Charlotte. The three lakes are, or until recently were, discharge sites for effluents from coal-fired power plants. Four types of fish tissue were analyzed: liver, muscle, ovary and testes.

The team also measured selenium in water, sediment and fish tissues in three similar lakes -- Adger, Tillery and Waccamaw -- with no such history of contamination. Samples were collected over a three-month period in spring 2015.

"Catastrophic releases of coal ash like the Dan River spill of 2014 get all of the attention, but there is ongoing, continuous contamination of aquatic ecosystems from hundreds of coal ash ponds across the country," Brandt said. "People fish in these lakes for recreation and subsistence purposes. We want to protect these public resources."

The EPA recently revised its selenium threshold criteria for aquatic health, and now places greater weight on concentrations in tissue rather than in water for evaluating ecosystem impacts.

"Selenium concentrations in surface water don't tell us as much about the risk of exposure to fish," Brandt explained.

Of the three coal ash discharge lakes tested in the new study, Sutton Lake had the highest levels of selenium. Eighty-five percent of all fish muscle samples examined there contained selenium levels above the EPA's threshold.

In Mayo Lake, 27 percent of muscle samples exceeded the EPA criteria.

Levels were below the EPA criteria in Mountain Island Lake.

North Carolina has new coal ash management rules in place to close coal ash ponds at some power plants, Brandt noted. "But it will be important to continue monitoring sediments and fish tissues at these sites after the selenium inputs are stopped," she said. "You have to look beneath the surface to understand how these problems persist over time."

The new study did not evaluate potential human health risks posed by the coal ash residual contamination.
-end-
Co-authors of the new study were Emily Bernhardt, professor of biogeochemistry; Gary Dwyer, senior research scientist, and Richard Di Giulio, Sally Kleberg Professor of Environmental Toxicology, all of Duke.

Primary funding came from the North Carolina Water Resources Research Institute.

Additional support came from an Environmental Protection Agency STAR Fellowship (#FP-91780101-1), the National Institute of Environmental Health Science (#T32-ES021432), and The Foundation for the Carolinas.

CITATION: "Selenium Ecotoxicology in Freshwater Lakes Receiving Coal Combustion Residual Effluents: A North Carolina Example," Jessica E. Brandt, Emily S. Bernhardt, Gary S. Dwyer, Richard T. Di Giulio; Environmental Science & Technology, Feb. 6, 2017. DOI: 10.1021/acs.est.6b05353

Duke University

Related Selenium Articles from Brightsurf:

Surrey reveals simple method to produce high performing Lithium Selenium batteries
Engineers at the University of Surrey have developed a simple and elegant method of producing high-powered lithium-selenium (Li-Se) batteries.

Easy to overdose on paracetamol if you're selenium deficient, says research
A lack of the mineral selenium in the diet puts people at risk of paracetamol overdose, even when the painkiller is taken at levels claimed to be safe on the packaging, according to collaborative research emerging from the University of Bath and Southwest University in China.

Link identified between dietary selenium and outcome of COVID-19 disease
An international team of researchers, led by Professor Margaret Rayman at the University of Surrey, has identified a link between the COVID-19 cure rate and regional selenium status in China.

Stream pollution from mountaintop mining doesn't stay put in the water
Since the 1980s, a mountaintop mine in West Virginia has been leaching selenium into nearby streams at levels deemed unsafe for aquatic life.

Spinal deformities in Sacramento-San Joaquin delta fish linked to toxic mineral selenium
Native fish discovered with spinal deformities in California's Sacramento-San Joaquin Delta in 2011 were exposed to high levels of selenium from their parents and food they ate as juveniles in the San Joaquin River, new research has found.

Agricultural area residents in danger of inhaling toxic aerosols
Excess selenium from fertilizers and other natural sources can create air pollution that could lead to lung cancer, asthma, and Type 2 diabetes, according to new UC Riverside research.

It's a small (coal-polluted) world, after all
A study published in Environmental Toxicology and Chemistry underscores that the release of pollutants in one region can have implications beyond its borders; emphasizing the dire need for global collaboration on environmental issues.

Russian scientists studied the effect of selenium on the properties of basil
Today many agricultural plants are grown using hydroponics, i.e. in artificial soilless environments.

Turning to old remedies for new health challenges
The last thing anyone wants during a stay in the hospital is a hospital-acquired infection.

Selenium anchors could improve durability of platinum fuel cell catalysts
Researchers at the Georgia Institute of Technology have developed a new platinum-based catalytic system that is far more durable than traditional commercial systems and has a potentially longer lifespan.

Read More: Selenium News and Selenium Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.