Fig. 6

Calculated time trends for PFOS in human and food samples. a Study period and direction of trend. Datasets above the thick horizontal line were analysed for change-points. Other data sets provided less than 7 time points and were not analysed for change-points. The power of insignificant trends refers to the chance of detecting an annual change of 10%. b Magnitude of annual change. Where change-points occur the magnitude is generally shown before and after the change-point, but where the trend is insignificant on both sides the magnitude is shown for the whole period only. Colour codes are the same in a, b. Bullets indicate that time trend analysis was performed also in the original study (reference in square brackets). Asterisks indicate low risk of bias, other studies were judged to have medium risk of bias