Ratios of [X]/[CH₃OH] towards SMM1-a (red) and IRAS 16293B (blue) in decreasing order of SMM1-a abundance. The ‘ ~’ symbol indicates that these HOCH₂CN ratios have been determined with the column density of the tentative HOCH₂CN detection towards the IRAS 16293B full-beam offset position. For IRAS 16293B, column densities derived towards the full-beam offset position from the following PILS publications are used. ^a This work, ^b Ligterink et al. (2017), ^cCoutens et al. (2016), ^dJørgensen et al. (2016, 2018), ^eCalcutt et al. (2018), ^fPersson et al. (2018), ^gCoutens et al. (2018).