SEDIMENT LOADS OF POLYCHLORINATED BIPHENYL (PCBS) IN BAKANA CREEK, IN THE NIGER DELTA REGION OF NIGERIA.

Abstract

PCBs are produced as blends of 60 to 90 distinct congeners, they are environmentally toxic, thus,
classified as persistent organic pollutants (POPs) and have strong affinity with sediments. This purpose
of this study is to assess the levels of PCB accumulation and identify the types of PCBs present in the
sediments of Bakana Creek, Rivers State, Nigeria. Sediment samples were collected randomly from the
study area. Gas chromatograph (Agilent 7890A, Palo Alto, CA, USA) with electron capture detection
(ECD) were used to determine the PCB levels and types. The total mean concerntration and types of
PCB in the 5 stations obtained from sediment are in decreasing mean order of; PCB 1248 (94.93±14.19)
>> PCB 1232 (66.79±18.17) >> PCB 1221 (62.10±3.25) >> PCB 1242 (43.49±10.98) >> PCB 1260
(35.72±6.34) >> PCB 1016 (20.36±2.19) >> PCB 1254 (17.88±10.32). The concentration of PCBs from
the Bakana Creek were significantly higher at (p<0.05) as shown by (ANOVA). Tukey HSD Post-hoc
comparison reveals that PCB 1221, 1232 and 1248 bio-accumulated more strongly than the other
congeners. PCB exceeded the Canadian Sediment Quality standard threshold effect level (CSQ TEL)
of (0.03 μg/kg) and the United State Environmental Protection Agency (USEPA) permissible limit of
0.0005 ppm for Sediment. This implied that there are potential health risk to those who are in contact
with sediment and those who consume organisms that inhabit the sediment of Bakana and it’s
surrounding on a daily basis. Indicating that the Bakana creek is under pollution threat and calls for
immediate attention.