Ubiquitous Occurrence of the Artificial Sweetener Acesulfame in the Aquatic Environment: An Ideal Chemical Marker of Domestic Wastewater in Groundwater

Abstract

Artificial low-calorie sweeteners are consumed in considerable quantities with food and beverages. After ingestion, some sweeteners pass through the human metabolism largely unaffected, are quantitatively excreted via urine and feces, and thus reach the environment associated with domestic wastewater. Here, we document the widespread occurrence of four sweeteners in the aquatic environment and show that one of these compounds, acesulfame, meets all of the criteria of an ideal marker for the detection of domestic wastewater in natural waters, particularly groundwater. Acesulfame was consistently detected in untreated and treated wastewater (12-46 microg/L), in most surface waters, in 65% of the investigated groundwater samples, and even in several tap water samples (up to 2.6 microg/L) from Switzerland. The sweetener was not eliminated in wastewater treatment plants (WWTPs) and was quite persistent in surface waters, where concentrations increased with population in the catchment area and decreased with water throughflow. The highest concentrations in groundwater, up to 4.7 microg/L, were observed in areas with significant infiltration of river water, where the infiltrating water received considerable discharges from WWTPs. Given the currently achieved detection limit of approximately 0.01 microg/L, it is possible to trace the presence of > or = 0.05% wastewater in groundwater.

Emerging organic contaminants in groundwater: A review of sources, fate and occurrence

“…While for many pharmaceuticals there are multiple sources in the environment globally, it is still possible to elucidate source terms on a local or sub-regional scale (e.g. Clara et al, 2004;Buerge et al, 2009Buerge et al, , 2011. The following sections critically review pollution of groundwater resources by EOCs from key point and diffuse sources.…”

“…Eckel et al, 1993;Holm et al, 1995), as well as indirectly through the process of groundwater-surface water (GW-SW) exchange (Buerge et al, 2009). …”

Antibiotics and sweeteners in the aquatic environment: biodegradability, formation of phototransformation products, and in vitro toxicity

“…Furthermore, persistent antibiotic compounds may contribute to the development of bacterial resistance, a feature that has already been described in various environmental compartments (Kiimmerer 2009) . Surprisingly, the two sweeteners cyclamate and saccharine could be classified as readily biodegradable although they have been detected in different aquatic media (Van Stempvoort et al 2011 ;Scheurer et al 2009;Buerge et al 2009). This apparent persistence, or pseudopersistence, clearly demonstrates that cyclamate and saccharine are discharged via wastewater at remarkably high quantities.…”

“…After ingestion, they pass through the human body, where they are largely unaffected by the metabolism, and reach the aquatic environment through domestic wastewater (Rodero et al 2009). They have been repeatedly detected in wastewater, groundwater, seawater, and tap water (Buerge et al 2009;Mead et al 2009;Van Stempvoort et al 2011). Because of their frequent occurrence in the aquatic environment (Table 1), artificial sweeteners are even used as anthropogenic wastewater markers (Buerge et al 2009;Oppenheimer et al 2012).…”

“…They have been repeatedly detected in wastewater, groundwater, seawater, and tap water (Buerge et al 2009;Mead et al 2009;Van Stempvoort et al 2011). Because of their frequent occurrence in the aquatic environment (Table 1), artificial sweeteners are even used as anthropogenic wastewater markers (Buerge et al 2009;Oppenheimer et al 2012). Their unintended presence in different aquatic compartments is a matter of concern, even though they undergo comprehensive toxicological testing prior to their use in consumer products (e.g., Grice and Goldsmith 2000;Weihrauch and Diehl 2004).…”