The Application of Passive Sampling Devices in Wastewater Surveillance

Wastewater-based epidemiology (WBE) is a surveillance approach used to examine chemical and biological targets within a population. Historically, the most common approaches to wastewater sampling include grab sampling and composite sampling, which can be performed manually or using an automated sampler. However, there are inherent flaws with these sampling methods. They can miss analytes due to fluctuation events in wastewater and can have high cost and labour implications. Alternately, passive sampling is a technique that involves a sampling medium that can stay in an aqueous matrix for extended periods of time to provide a greater temporal coverage. This literature review examines the current passive sampling devices used in wastewater surveillance and the general contaminants they are targeting. The polar organic chemical integrated sampler, Chemcatcher^®, diffusive gradients in thin films sampler and semipermeable membrane devices were among the most frequently deployed samplers in wastewater matrices. Chemical contaminants and pharmaceuticals were identified as the most common targets. Passive sampling of biological targets has received recent attention due to the surveillance of SARS-CoV-2; however, overall, there is a lack of critical knowledge relating to the deployment and associated variability of passive samplers used for biological targets. Notwithstanding, the ability of passive sampling to capture temporal fluctuation of analytes in wastewater make it a useful sampling technique for the surveillance of pathogens in the community. Future research should focus on addressing the gaps in knowledge to optimise the use of these sampling devices.