Previous studies have examined the effects of PFASs on immune-related health outcomes (e.g. cold and flu infections, ulcerative colitis, or inflammatory bowel disease) in adults and reported discordant results (Steenland et al. 2013, 2015; Looker et al. 2014; Xu et al. 2020); associations between PFASs and decreased levels of proteomic markers, such as tumor necrosis factor (TNF)-α and various interleukins (IL), have been reported (Bassler et al. 2019; Salihovic et al. 2020). This evidence concerns the gene TNF and ulcerative colitis.