Artificial Sugars Sweeten Tap Water in Canada
New research shows sweeteners evade wastewater systems, infiltrating watersheds and drinking water supplies
Do you try to avoid artificial sweeteners? Choose tap water over flavored waters, or lemonade over diet soda? Despite your best efforts, new research suggests that you may be ingesting small amounts of artificial sweeteners all the same.
photo by PacificKlaus, on Flickr
In a study conducted by Environment Canada and the University of Waterloo, researchers found high concentrations of artificial sweeteners in the Grand River in Ontario, Canada. Researchers sampled the river water at 23 sites, and found elevated concentrations of four sweeteners: cyclamate, saccharin, sucralose, and acesulfame. Acesulfame was the most persistent of the sweeteners, detected in 21 testing sites along 300 kilometers of the river.
“Artificial sweeteners are resistant to being broken down,” explains Professor John Spoelstra, an author of the study from University of Waterloo. “So they end up in the waste water system and the same chemical properties that make them resistant to being degraded in the body also make them resistant to being degraded in the wastewater system.” They also slip through water filtration systems, entering municipal water supplies.
However, sugary rivers may have an upside: They allow scientists to trace wastewater as it moves through watersheds. Artificial sweeteners, which are found primarily in human food, also allow for differentiation between human waste and agricultural waste within waterways.
“[Artificial sweeteners] offer a very powerful way for me to be able to tell whether a water body has been impacted by wastewater,” says Spoelstra. “The benefit of the sweeteners compared to other [[tracers] is that they are at pretty high concentrations that we can easily measure, and they seem to be more resistant to being broken down in the environment than some of the other compounds, so it makes them more of an ideal tracer.”
The study did not examine the potential impact of fake sugars on plants, animals, or people. It did note, however, that “aquatic organisms likely experience long-term exposure to significant concentrations of [artificial sweeteners] downstream of urban centers that discharge [wastewater treatment plant] effluents,” and that “impacts are not confined to the immediate reach below [wastewater treatment plants] but persist for hundreds of kilometers.”
Limited research has been conducted on these potential ecological impacts. One study found that exposure to the artificial sweetener sucralose can cause crustaceans to eat more, while another found that fake sugars impact crustaceans’ swimming speed. Other researchers, however, found that sucralose exposure had no impact on shrimp behavior or plant growth, and that artificial sweeteners do not bioaccumulate in algae or aquatic animals.
The jury is also out on whether artificial sweeteners are bad for human health. Several studies have suggested that artificial sweeteners can cause cancer in lab animals. High artificial sweetener intake has also been linked with weight gain, metabolic syndrome, Type II diabetes and cardiovascular disease. Other studies, however, have come to the opposite conclusion, showing that artificial sweeteners are unlikely to cause cancer in humans and can help with weight loss under certain circumstances. The National Cancer Institute has taken the position that artificial sweeteners are safe for humans, and the US Food and Drug Administration has approved them for human consumption.
Spoelstra assures us that artificial sweetener concentrations in our water, though high, cannot be compared to levels found in diet sodas and other flavored drinks: “In the river, the concentrations that we are seeing are tens of thousands to hundreds of thousands times lower than the artificial sweetener concentrations that you’d find in, say, a beverage that has been sweetened with artificial sweeteners.”