Comment on "Optimization of suspect and non-target analytical methods using GC/TOF for prioritization of emerging...

Lee et al. (2019) recently proposed that volatile methylsiloxanes (VMS) be considered as emerging contaminants in the Arctic environment based on the results of suspect and non-target screening of environmental samples collected from Ny-Ålesund, Svalbard. In any analytical program, it is of critical importance to be able to discern if the identification of analytes is due to true presence in the sampled environmental media or if contamination occurred during sample handling and analysis, leading to false positive detection. This is particularly important for VMS due to their ubiquity in consumer products, sample containers, and analytical instrumentation, thus requiring robust quality control (QC) procedures to support the validity of results. Although Lee et al. (2019) concluded that VMS in the environmental samples originated from potential long-range transport and deposition, it is most likely that local point sources account for their presence. Additionally, there is low confidence in the validity of the reported detection of VMS in the sampled environmental media as this study does not include any of the necessary QC to determine whether the VMS detected would be due to contamination or indicative of presence in the environment.