Fig. 2

Microbial reductive dechlorination of polychlorinated biphenyls (PCBs) in sewage sludge microcosms. a Decrease in average chlorine per PCB (Cl/PCB) after 180 days of incubation, b lag time distribution for the onset of PCB dechlorination, and c comparison of the chlorine removed from different positions of PCBs. The full names of city IDs are provided in Table S3. Asterisks indicate statistically significant differences at p < 0.05 inferred from ANOVA