The maximum oxygen uptake rate was 0.9 mg-O2 l−1 h−1 for benzene, 1.38 mg-O2 l−1 h−1 for toluene, 0.62 mg-O2 l−1 h−1 for ethylbenzene and 0.96 mg-O2 l−1 h−1 for p-xylene. The total amount of oxygen consumption was 6.65 mg l−1 for benzene, 6.58 mg l−1 for toluene, 3.66 mg l−1 for ethylbenzene and 7.22 mg l−1 for p-xylene.