By Kayla Cooke, contributing writer
A study by Dr. Sarah Whorley, an associate professor of biology at Daemen University, is shedding light on the long-term consequences of winter road salt on freshwater ecosystems. It reveals how rock salt pollution occurs all year long and affects aquatic life beyond the winter months.
Whorley, a professor and researcher at Daemen University, has been studying algae and anthropogenic disturbances since 2006. Road salt has recently become a specific focus of her work.
“I did not go to graduate school to study algae and freshwater. I did not know algae were a thing. I did not know people studied freshwater specifically,” said Whorley. “It was pretty interesting, and I wanted to continue working on it and doing more with it. So, I got an M.S. and then a PhD. That’s how I got started—by complete accident and happenstance.”
Now, Whorley’s research focuses on how road salt influences stream algae and macroinvertebrates, which are crucial bioindicators of aquatic health. With the Thruway Division of New York State applying over 180,000 tons of road salt, and likely more when including towns, cities, and counties—there is increasing concern about long-term ecological consequences.
“It is non-intuitive that climate change and specifically the warming aspect of climate change leads in some places, in some circumstances, to more cold and snow[y],” Whorley explained. “This winter alone, we had over 45 straight days of measurable snowfall, and that was all because of cold air interacting with the unfrozen waters of Lake Erie until it finally got cold enough for long enough that the lake could freeze.”
Increased snowfall leads to more road salt application, and colder temperatures make it necessary for the use of more aggressive de-icing agents such as magnesium chloride and calcium chloride
“The problematic part of salt for organisms is not just saltiness for the sake of saltiness. It’s that chloride ion,” Whorley said. “When you use different salts for colder temperatures like magnesium or calcium chloride, you get more chloride per unit of salt, which can have significant ecological consequences.”
Whorley and her team measured chloride’s impact on freshwater life by analyzing stream samples for biochemical changes. Her research team includes undergraduate students Sage Sellers, Madelyn Casselman, and Blake Pahuta, who are investigating topics ranging from algal biochemical properties to the effects of road salt on freshwater ecosystems.
“Some previous work found that when we looked at algae ratios of omega-3 to omega-6 fatty acids, the number of omega-6s was increased with salinity,” Whorley explained. “In high-salinity circumstances, omega-6s were almost double the amount of omega-3s. This road salt is potentially increasing the amount of omega-6s in algae while suppressing omega-3 fatty acid production.”
This shift in fatty acid composition could have cascading effects on the entire aquatic food web. These omega-6 fatty acids may affect the immune-inflammatory system, the hypothalamic-pituitary-adrenal (HPA) axis, and the autonomic nervous system (ANS), all involved in stress responses.
“If macroinvertebrates are increasingly eating stressed-out food, are they going to become stressed out themselves? What happens to their physiology, reproductive health, and the fish that eat them?” Whorley asked. “We might be in the process of turning the base of our food web into basically inflammatory junk food.”
The broader implications of this study extend beyond just aquatic organisms.
“We are really all interconnected. There’s no escaping it,” Whorley said. “We might not want to be interconnected, but we are all connected to every other group of living things out there.” While road salt is widely used for safety, alternative de-icing methods could help reduce environmental damage.
“Wisconsin has experimented with different forms of road deicer, including whey leftover from cheese production, which contains proteins and amino acids that prevent ice formation,” Whorley noted. “Some areas also use sugar beet extracts, sand, and grit instead of chemical salts. There are also ideas that we should shift our work mentality so that snow days become work-from-home days, reducing the need for road salt altogether.”
Other potential solutions involve increasing public transportation usage and reconsidering how roads are maintained during winter storms.
“Using mass transit more would mean fewer cars on the road, which could reduce the need for plowing and salting,” Whorley suggested. “There are also ideas that we should go back to using tire chains instead of depending entirely on salt.”
Whorley’s research is ongoing, with potential expansion beyond New York.
“Right now, we’re surveying 30 streams across the state, but I’ve received a lot of interest from colleagues in other states like New Jersey and North Carolina,” Whorley said. “It would be interesting to compare salting regimes in different climates and assess how different levels of road salt use impact aquatic ecosystems.”
However, balancing research with teaching remains a challenge.
“At a place like Daemen University, teaching always has to come first,” Whorley said. “I’m dedicated to advancing scientific understanding and inspiring students to engage in environmental research.”
“We’re all, you know, aiming high, dreaming big, and doing what we can do. Our little piece of the scientific puzzle is all we always aim to contribute to.” Whorley added.