To demonstrate the change in concentrations and trends over the years, Figure presents a comparison of pre-2010 and post-2010 data (by the reported year of sampling, not the year of publication). This cut-off year of 2010 was chosen because there was a slump of interest in TFA in the peer-reviewed literature between the years 2008 to 2012. Prior to this time, research on TFA attracted attention in relation to the introduction of F-gases around the late 1990s to replace CFCs. In more recent years, TFA has attracted increased attention due to it more commonly being included and detected during PFAS monitoring campaigns. The 1 st of January 2010 also coincides with the final deadline for stopping the last remaining production of CFCs ; even though the transition to F-gases occurred much before this time. In cases of either green or red bars and dots missing, data were not available for the given media and/or timeframe. For air concentrations before 2010 only two studies were available, one of which reported only mean measured concentrations (see Table for the full data set and Figure for air data presented as concentrations from individual studies).