Spatial Distribution of PCB Dechlorinating Bacteria and Activities in Contaminated Soil

Table 4

Effect of inhibition on the dechlorination activity in microcosms using selected soil and sediment samples mixed 1 : 1 with actively dechlorinating sediment from Baltimore Harbor. Inhibition was determined (𝑃<0.05) for the dechlorination rate and terminal plateau. Lag phase is defined as not showing activity that is different from the autoclaved negative control.

Location	Lag phase (d)	PCB 116 remaining after 200 days; (mol% 2,3,4,5,6-CB)	Dechlorination rate · 10^−3; (% 2,3,4,5,6-CB day^−1)	End product	Inhibition (𝑃<0.05)
					Rate	Plateau
Baltimore Harbor	0–50	5.7±4.5	9.1±2.2^b	2,4,6-CB^a	—	—
Meb6	0–50	31.3±15.9	7.3±1.0	2,4,6-CB	No	Yes
Meb7	0–50	10.7±3.5	12.4±1.1	2,4,6-CB	No	No
Meb8	0–50	21.0±19.2	8.4±3.7	2,4,6-CB	No	No
Meb17	0–50	46.3±6.5	7.5±2.2	2,4,6-CB	Yes	Yes
Meb18	0–50	45.7±10.1	10.5±2.2	2,4,6-CB	No	Yes

^aOne tube showed additional terminal products such as 2,4-CB, 2,5-CB, and 2,6-CB.
^bData are means ± standard deviation (𝑛=3).