Development and validation of a retracted thin film solid phase microextraction device for time weighted average monitoring of artificial sweeteners concentration in surface waters

Abstract

A retracted thin-film solid phase microextraction device was used as a passive sampler to monitor the time-weighted average concentration of artificial sweeteners (AS) in Grand River, Ontario, Canada. Laboratory and field calibration were performed to determine differences in the estimated sampling rate values. Laboratory sampling rates ranged from 0.0033 mL day^-1 for neohesperidin dihydrochalcone to 0.0075 mL day^-1 for saccharin. Sampler devices were deployed for 30 days downstream of a municipal wastewater treatment plant in the Grand River, Ontario, Canada. Linear accumulation for four AS was observed (R²>0.9363) in the sampling devices over 30 days, and in-situ sampling rates were between 0.0045 ± 0.0002 for sucralose and 0.0070 ± 0.0009 mL day^-1 for acesulfame. The estimated sampling rates for the river and laboratory exhibited <20 % deviation from the theoretical values. Simultaneously, water samples from the Grand River were collected to determine the concentration levels of artificial sweeteners. The concentration of acesulfame, saccharin, cyclamate, aspartame, and sucralose in the Grand River ranged from 0.13 to 26.5 ng mL^-1. The validation results indicated that this device is suitable for long-term monitoring of AS in surface waters.