For quality control, peak areas of the internal standards in ESI-mode were inspected in MS 1 mode for both SWATHonly and MRM-HR+SWATH. From the labeled IS employed, none was found to be ionized in ESI+ so, relative standard deviation values (RSD) were only estimated to be similar to ESI-. Peak areas for MRM+SWATH mode have presented higher RSD (Table ), which may be explained by the lower values for peak areas. These may additionally be related to the fact that accumulation time at MS 1 for SWATH-only in ESI-mode was set three times higher than MRM-HR + SWATH, therefore providing better sensitivity. Nevertheless, it is also important to highlight that this variation is likely to be considerably smaller for the MS 2 data in MRM-HR + SWATH due to the increased peak areas provided by the Zeno Pulsing technique, which is, in fact, the data presented and evaluated along this work. In addition, labeled IS were added to the extraction solution and, therefore, account for the sum of the variances of both extraction process and analytical run. For PFOS for example, recovery at very low concentration was reported as 56 ± 25%, representing 50% of variance only related to sample preparation. As the average RSD was significantly below this value, we may infer that analytical variance was minimal. Total variance for recovery was also reported for genistein and estradiol at 30% and 14%, respectively, while RSD in our analysis were at 24% and 23% for MRM-HR+SWATH data. Finally, MS A spectral match score of 70% was used as a threshold, with no limitation for minimum dot and reverse dot-products scores (since data was manually curated afterwards). All method parameters from MS-Dial (from peak detection to identification) are described in Table .