Note the logarithmic scale of the y-axis. Boxes represent the median and interquartile range, whiskers represent highest and lowest peak area detected, and dots represent samples. Groups are not shown when the compound was not detected. Significance level is taken as p value <0.05, adjusted for comparison (Bonferroni). *p < 0.05; **p < 0.01; ***p < 0.001. CA corrected age.