Determination of Total Potency Equivalent Concentration (Tpec) of Carcinogenic Polycyclic Aromatic Hydrocarbons (Cpahs) In Soils of Bodo-City

The aim of this paper is to report the determination of Total potency equivalent concentration (TPEC) of Carcinogenic polycyclic aromatic hydrocarbons (cPAHs) in soil samples from Bodo area in Ogoniland  using the Toxicity Equivalent Factor (TEF) model. Gas Chromatography GC HP 5870 with FID was used for  analysis. Out of the seven cPAHs investigated only three were detected. They are Benzo (a) Pyrene (BaP), Dibenzo (a, h) anthracene and Indeno (1, 2, 3-cd) pyrene with soil concentrations of 19.06 mg/kg, 6.67 mg/kg and 29.26 mg/kg respectively. Their correspondingly individual potency equivalent  concentrations in soil (mg/kg) are 19.06, 0.67 and 2.93 respectively. Benzo (k) Fluoranthene, Benzo (a)  Anthracene, Benzo (b) Fluoranthene and Chrysene was not detected. The calculated TEQ or TPEC is  22.66mg/kg and this value by far exceeds the method B cleanup levels of BaP value of 0.137mg/kg, it suggests a massively contaminated soil. TPEC is 226.6 times higher than the method B and CAL-EPA risk-based cleanup value of 0.1mg/kg while Total cPAHs is 549.9 times higher than the risk-based cleanup value as indicated. This level of soil toxicity with respect to BaP indicates that the area should be declared a no-go area for humans and animals alike. We strongly  recommend the application of Dispersion by  Chemical Reaction Technology, should be deployed immediately in this area for total detoxification and  decontamination of the area.Keywords: TEQ, TEF, PEF, cPAHs, BaP, Bodo, risk assessment

Heavy metal profiles in various matrices of the Bonny/New Calabar River Estuary, Niger delta, Nigeria

A study of the concentrations of Ca, Mg, K, Zn, Pb, Cd, Co, Cr, Cu, Fe, Ni and Na in the sediment, sea water, fish and crab of the Bonny/New Calabar River Estuary in Niger Delta, Nigeria was carried out using atomic absorption spectrophotometer A-100 for two consecutive years. The contamination levels of the respective metals varied between 2011 and 2012and the range of mean values for all metals in mg/kg were presented along with variations at statistically significant level (P <0.05) between the two years studied. Only K, Zn and Co exhibited variation in their concentrations in water samples between the two years at a statistical significant level (P <0.05) probability. In sediment, only Cr varied between the two years at a statistically significant level (P = 0.05). All metals concentrations were higher in sediment than in water samples.Bioaccumulation factor (BF) indicated a more potent source of metals from sediment than water with organisms accumulating Zn, Fe and Ni in the magnitude of 10, 6 and 5 times more from sediment than from water. Some metals were more accumulated in fish than crab and vice versa. The evidence of elevated levels of heavy metals in sediment and bioaccumulation in biota in the studied area may poise a wanton threat to the health of inhabitants whose diet is predominantly fish. This calls for regular monitoring to avert potential public health problems arising from consumption of metals in seafood. Keywords: Heavy metals, Matrices, bioaccumulation, Bonny River, Niger Delta, Nigeria

River water quality assessment using environmentric techniques : case study of Jakara River Basin.

akara River Basin has been extensively studied to assess the overall water quality and to identify the major variables responsible for water quality variations in the basin. A total of 27 sampling points were selected in the riverine network of the Upper Jakara River Basin. Water samples were collected in triplicate and analyzed for physicochemical variables. Pearson product-moment correlation analysis was conducted to evaluate the relationship of water quality parameters and revealed a significant relationship between salinity, conductivity with dissolved solids (DS) and 5-day biochemical oxygen demand (BOD5), chemical oxygen demand (COD), and nitrogen in form of ammonia (NH4). Partial correlation analysis (r p) results showed that there is a strong relationship between salinity and turbidity (r p = 0.930, p = 0.001) and BOD5 and COD (r p = 0.839, p = 0.001) controlling for the linear effects of conductivity and NH4, respectively. Principal component analysis and or factor analysis was used to investigate the origin of each water quality parameter in the Jakara Basin and identified three major factors explaining 68.11 % of the total variance in water quality. The major variations are related to anthropogenic activities (irrigation agricultural, construction activities, clearing of land, and domestic waste disposal) and natural processes (erosion of river bank and runoff). Discriminant analysis (DA) was applied on the dataset to maximize the similarities between group relative to within-group variance of the parameters. DA provided better results with great discriminatory ability using eight variables (DO, BOD5, COD, SS, NH4, conductivity, salinity, and DS) as the most statistically significantly responsible for surface water quality variation in the area. The present study, however, makes several noteworthy contributions to the existing knowledge on the spatial variations of surface water quality and is believed to serve as a baseline data for further studies. Future research should therefore concentrate on the investigation of temporal variations of water quality in the basin

Surface water quality contamination source apportionment and physicochemical characterization at the upper section of the Jakara Basin, Nigeria.

The present study investigates the surface water quality of three important tributaries of Jakara Basin, northwestern Nigeria to provide an overview of the relationship and sources of physicochemical and biological parameters. A total of 405 water samples were collected from 27 sampling points and analyzed for 13 parameters: dissolved oxygen (DO), 5-day biochemical oxygen demand (BOD5), chemical oxygen demand (COD), suspended solids (SS), pH, ammonia-nitrogen (NH3NL), dissolved solids (DS), total solids (TS), nitrates (NO3), chloride (Cl), phosphates (PO4), Escherichia coli (E. coli) and fecal coliform bacteria (FCB). Pearson’s product–moment correlation matrix and principal component analysis (PCA) were used to distinguish the main pollution sources in the basin. Four varimax components were extracted from PCA, which explained 84.86, 83.60, and 78.69 % of the variation in the surface water quality for Jakara, Tsakama, and Gama-Kwari Rivers, respectively. Strong positive loading included BOD5, COD, NH3NL, E. coli, and FCB with negative loading on DO attribute to a domestic waste water pollution source. One-way ANOVA revealed that there was no significant difference in the mean of the three water bodies (p > 0.05). It is therefore recommended that the government should be more effective in controlling the point source of pollution in the area