DEC 29, 2018 6:56 PM PST

Fish ear bones track coal ash contamination

Coal ash contamination is a public health threat across the United States. Coal ash refers to the toxic remains of coal burning in power plants. The chemicals in coal ash are known carcinogens and also cause developmental disorders and reproductive problems, according to Earth Justice. When coal ash gets into waterways and ecosystems, it leaves death in its wake, poisoning fish and wildlife. However, despite its known dangers, the Environmental Protection Agency has not taken major action to monitor and protect the waters we drink, so US waters remain contaminated.

But new research from Duke University published in Environmental Science & Technology Letters has unearthed a new tool to identify and track coal ash contamination – and it comes from an unlikely source: the ear bones of fish.

Jessica Brandt, the lead author of the paper, explained that her team used isotope ratios in fish ear bones (called otoliths) to analyze the presence of coal ash contamination in two North Carolina lakes that had been impacted by effluents from coal ash ponds at nearby power plants. "Calcified structures -- or otoliths -- found in a fish's inner ear are known to store a lot of life history information, including chemical and physical records of the fish's age, natal habitat, and migration patterns. We've shown that otoliths also capture the signatures of contaminants that have affected the fish's ecosystems,” Brandt said.

The specific isotope that the team analyzed was strontium. According to Science Daily, strontium is unique in that it is a naturally occurring trace element in coal that retains isotopic ratios even after the coal is burned and coal ash is introduced to an aquatic environment.

The team was able to verify the origins of the coal ash because strontium isotope ratios in the otoliths of fish matched the strontium isotope ratios in samples collected from sediment at the bottom of the lakes. "This shows otoliths can be used as biogenic tracers to assess the potential for ecological impacts of coal ash waste streams in affected waters," said Brandt.

Coal ash is toxic to humans and wildlife. Photo: Tree Hugger

The potential of this new, surprising tool is vast. "This study's finding demonstrates that otolith studies can add to our existing research efforts," said Brandt. "Water-based strontium isotope tracers only give us information about coal ash impacts at a particular point in time, but because otoliths continuously grow over a fish's lifetime, we could use time-series analyses of otoliths to determine the timing of waste stream discharges or spills going back several years. This represents an emerging and important new direction in environmental toxicology and water-quality research."

Sources: Science Daily, Earth Justice, Environmental Science & Technology Letters

About the Author
BA Environmental Studies
Kathryn is a curious world-traveller interested in the intersection between nature, culture, history, and people. She has worked for environmental education non-profits and is a Spanish/English interpreter.
You May Also Like
JUL 12, 2022
Technology
Using Fiber Optic Cables to Detect Glacial Volcano Tremors
JUL 12, 2022
Using Fiber Optic Cables to Detect Glacial Volcano Tremors
Subglacial volcanoes are the result of volcanic activity that takes place beneath a glacier. As the result of magma and ...
JUL 20, 2022
Technology
More efficient and faster devices from electron spin control
JUL 20, 2022
More efficient and faster devices from electron spin control
A recent collaborative research study between the Rensselaer Polytechnic Institute and the University of California at S ...
JUL 26, 2022
Cannabis Sciences
Formation of toxic ketene likely caused by vaping cannabinoid acetates
JUL 26, 2022
Formation of toxic ketene likely caused by vaping cannabinoid acetates
A recent peer-reviewed study conducted at Portland State University and slated to be published in Chemical Research and ...
JUL 30, 2022
Earth & The Environment
Climate Change Causing Hot Trouble for Lakes
JUL 30, 2022
Climate Change Causing Hot Trouble for Lakes
A recent study from a collaborative research team and published in BioScience discusses how consequences from climate ch ...
AUG 09, 2022
Earth & The Environment
Tropical ozone hole larger than Antarctic ozone hole
AUG 09, 2022
Tropical ozone hole larger than Antarctic ozone hole
In a recent single-author study published in AIP Advances, Qing-Bin Lu, a scientist from the University of Waterloo in O ...
AUG 13, 2022
Plants & Animals
Phosphorus Deficiencies Limit Plant Growth in the Amazon
AUG 13, 2022
Phosphorus Deficiencies Limit Plant Growth in the Amazon
One key nutrient plants need to thrive and survive is CO2, which is why plants have been a vital part of maintaining pla ...
Loading Comments...