20 June 2009
The bitter side of sweeteners
Sewage treatment plants fail to remove artificial sweeteners completely from waste water. What's more, these pollutants contaminate waters downstream and may still be present in our drinking water. Thanks to their new robust analytical method, which simultaneously extracts and analyses seven commonly used artificial sweeteners, Marco Scheurer, Heinz-Jürgen Brauch and Frank Thomas Lange from the Water Technology Center in Karlsruhe, Germany, were able to demonstrate the presence of several artificial sweeteners in waste water. Their findings(1) are published online this week in Springer's journal Analytical and Bioanalytical Chemistry.
A range of artificial sweeteners are commonly used in food and drinks, as well as drugs and sanitary products. The potential health risks of artificial sweeteners have been debated for some time. Until now, only sucralose has been detected in aquatic environments. Through the use of a new analytical method, the researchers were able to look for seven different artificial sweeteners (cyclamate, acesulfame, saccharin, aspartame, neotame, neohesperidin dihydrochalcone and sucralose) simultaneously, and show, for the first time, that a number of commonly used artificial sweeteners are present in German waste and surface water.
Scheurer and colleagues collected water samples from two sewage treatment plants in Germany – Eggenstein-Leopoldshafen and Karlsruhe – as well as from a soil aquifer treatment site located in a Mediterranean country that treats secondary effluent from a sewage treatment plant.
They tested the water samples using their new analytical method and detected four (acesulfame, saccharin, cyclamate, and sucralose) of seven artificial sweeteners in the waters from the two German sewage treatment plants, indicating incomplete elimination during waste water treatment. Their analyses also showed that these pollutants contaminate rivers and streams receiving water from the sewage treatment plants.
The authors then compared the conventional waste water treatment by sewage treatment plants with advanced waste water treatment by soil aquifer treatment. Traces of artificial sweeteners were present in both cases, proof that water purification was incomplete.
Marco Scheurer concludes: "Due to the use of artificial sweeteners as food additives, the occurrence of artificial sweetener traces in the aquatic environment might become a primary issue for consumer acceptance."