Intraradical PAH content (lower part of bar) and extraradical PAH content (upper part of bar) of mycorrhizal carrot roots (M) and non-mycorrhizal carrot roots (NM) expressed as mmoles mg1 root dry weight in the presence of anthracene (a), phenanthrene (b) and dibenzothiophene (b). Data represents means of 6 values. Error bars represent standard deviation (n 1⁄4 3). For clarity, only a positive or a negative direction error bar is shown for each stacked bar.