Distribution of Four Artificial Sweeteners in Water Treatment and Water Supply System in City H of Zhejiang Province

Abstract

Taking the sewage and drinking water treatment system of two cities in Zhejiang Province as the main research target, a systematic investigation on the common artificial sweeteners was carried out by solid phase extraction-high performance liquid chromatography (SPE-HPLC). The results showed that SPE-HPLC can accurately determine micro acesulfame (ACE), saccharin (SAC), aspartame (ASP), and neotame (NEO) in water. The detection limits were 57, 120, 170, and 47 μg·L-1, and the quantification limits were 190, 400, 567, and 157 μg·L-1, respectively. After optimization of the solid phase extraction procedure when using PWAX columns, the recoveries of ACE and SAC were enhanced to 86.5% and 97.7%; however, it slightly decreased to 66.5% for NEO. The occurrence rates of ACE, SAC, and NEO in domestic sewage were 100.0%, and it was only 33.3% for ASP. The highest concentrations of four aforementioned artificial sweeteners in domestic sewage were 0.83, 4.52, 1.22, and 7.57 μg·L-1, respectively. The highest concentrations of acesulfame, saccharin, aspartame, and neotame in source water were 22.94, 39.17, 0.73, and 8.92 μg·L-1, respectively, and detection rates were 72.7%, 90.9%, 18.2%, and 90.9%, respectively. Most artificial sweeteners were removed by the prozone process; the removal efficiencies of ACE, SAC, and NEO ranged from 67.7% to 100.0%, and the removal efficiencies of ACE, SAC, and NEO by the advanced treatment process ranged from 73.7% to 100.0%, which effectively reduced the risk of drinking water quality. The four artificial sweeteners were not detected in the water supply network.