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

Source Apportionment of Polycyclic Aromatic Hydrocarbons in Indoor Fine Dusts from Residential and Public Buildings in Port Harcourt, Rivers State, Nigeria

The sources of polycyclic aromatic hydrocarbons in indoor fine dust from residential and public buildings in Port Harcourt, Rivers State, Nigeria was investigated using source apportionment tools such as diagnostic/isomeric ratios, principal component analysis (PCA) and hierarchical cluster analysis (HCA). A total of twenty-seven indoor fine dusts comprising of twenty samples from residential building and seven samples from public buildings were collected from Port Harcourt. The PAHs in the dust samples were quantified by gas chromatograph equipped with mass spectrometry (GC-MS) after extraction by ultra-sonication with hexane/dichloromethane/acetone and cleaned up   on a silica gel/alumina column. The Σ16 PAH concentrations in the indoor fine dusts ranged from 3136 µg kg-1 to 44332 µg kg-1 for residential buildings and 2580 µg kg-1 to 15372 µg kg-1 for public buildings. The results of source apportionment indicated that the PAHs in the indoor fine dusts were from mixed sources pyrogenic sources (coal, wood, petroleum, biomass, and fossil fuel combustion) and petrogenic sources with significant contribution from pyrogenic sources

USE OF ALKYL POLYGLYCOSIDES IN THE REMEDIATION OF HEAVY METALS FROM HYDROCARBON CONTAMINATED SOILS

Heavy metal contamination of soil is a global issue because of the accumulation of these compounds in the environment, endangering human health, plants, and animals. This research investigated surfactant enhanced remediation of heavy metals such as of Fe, Zn, Pb, Ni, Cr, and Cu in hydrocarbon contaminated soil samples from Eneka, Ozuoba and Rukpokwu. The soil samples were contaminated with medium and light crude oil, and the concentrations of heavy metals were analysed with Atomic Absorption Spectroscopy. Results obtained from the medium crude contaminated soil samples before remediation showed: Cu: 5.82mg/kg, Fe:11897.00 mgkg-1, Zn :129.00 mgkg-1, Pb: 6.80 mgkg-1, Ni:11.60 mgkg-1, Cr: 20.70 mgkg-1 for soil samples from Eneka. The metal concentrations were reduced to 3.80 mgkg-1, 2013.00 mgkg-1, 29.40 mgkg-1, < 0.012 mgkg-1, <0.008 mgkg-1, and <0.005 mgkg-1 respectively after remediation. The results of the soil samples from Ozuoba were: Cu: 3.04 mgkg-1, Fe: 7197.00 mgkg-1, Zn: 51.80 mgkg-1, Pb: 3.10 mgkg-1, Ni: 11.90 mgkg-1, Cr: 37.90 mgkg-1 before remediation. The concentrations of the metals were reduced to 1.27 mgkg-1, 2017.00 mgkg-1, 19.40 mgkg-1, 0.012 mgkg-1, <0.008 mgkg-1 and < 0.005 mgkg-1 respectively after remediation. The results of soil samples from Rukpokwu were: Cu: 3.56 mgkg-1, Fe: 4188.00 mgkg-1, Zn: 111.00 mgkg-1, Pb: 1.04 mgkg-1, Ni: 9.50 mgkg-1, Cr: 34.50 mgkg-1 before remediation. The concentrations of the heavy metals were reduced to 1.57 mgkg-1, 2034.00 mgkg-1, 16.00 mgkg-1, <0.012 mgkg-1, <0.008 mgkg-1 and <0.005 mgkg-1 respectively after remediation. The soil samples contaminated with light crude showed the following results before remediation; Cu: 5.04 mgkg-1, Fe: 10495.00 mgkg-1, Zn: 97.50 mgkg-1, Pb: 4.70 mgkg-1, Ni: 8.44 mgkg-1, Cr: 19.00 mgkg-1 for Eneka:. The concentrations of the metals were reduced to 2.86 mgkg-1, 2080.00 mgkg-1, 27.20 mgkg-1, <0.012 mgkg-1, <0.008 mgkg-1 and <0.005 mgkg-1 after remediation. The results of soil samples from Ozuoba are as follows: Cu:1.13 mgkg-1, Fe: 5504.00 mgkg-1, Zn:43.00 mgkg-1, Pb: 2.70 mgkg-1, Ni: 12.10 mgkg-1, Cr: 17.20 mgkg-1 before remediation. The concentrations were reduced to 0.21 mgkg-1, 1909.00 mgkg-1, 12.20 mgkg-1, <0.012 mgkg-1, <0.008 mgkg-1 and <0.005 mgkg-1 after remediation. The soil samples from Rukpokwu showed the following results before remediation: Cu: 2.43 mgkg-1, Fe: 4572.00 mgkg-1, Zn: 65.30 mgkg-1, Pb: 0.86 mgkg-1, Ni 13.70 mgkg-1, Cr: 20.70 mgkg-1. These concentrations were reduced to 0.26 mgkg-1, 1841.00 mgkg-1, 15.30 mgkg-1, <0.012 mgkg-1, <0.008 mgkg-1, and <0.005 mgkg-1 after remediation. The results of this study showed that the concentrations of Pb, Ni, and Cr were removed to below the detection limit of the equipment. Fe and Zn showed a very high degree of success, achieving a 60% to 83% reduction in all soil. The removal of Cu from the Eneka sample showed the least removal tendency of 33.51% in medium crude contaminated soil and 43.25% in light crude contaminated soil. The use of alkyl polyglucoside surfactant enhanced the solubilisation and surfactant-metal complexation, resulting in the removal of these heavy metals from hydrocarbon contaminated soils

REMEDIATION OF HYDROCARBON CONTAMINATED SOILS USING PULVERIZED OYSTER AND SNAIL SHELLS

Hydrocarbon contaminated soil were collected and treated with pulverized oyster and snail shells which served as adsorbents for remediation of the impacted sites. Gas Chromatography flame ionization detector was used to determine the Total petroleum hydrocarbon of the seven soil samples. Results obtained showed the concentrations of Total hydrocarbon for samples 1, 2 and 3 before treatment were 14655.00 mg/kg, 12412.00 mg/kg and 14906 mg/kg respectively. The hydrocarbon impacted soil samples were treated with pulverized oyster shell and after thirty days, results were 6188.00mg/kg; 8543.00 mg/kg and 12612.00 mg/kg respectively. Similarly samples 4, 5 and 6 showed the following results before treatment: 11295.00 mg/kg; 9456.00 mg/kg and 12246 mg/kg respectively. The soil samples were treated with pulverized snail shell and after thirty days, the results were: 5924.00 mg/kg; 6918.00 mg/kg and 10532 mg/kg. The result of the control sample which was not treated was 13641.00 mg/kg. The calculated percentage reduction of petroleum hydrocarbons in samples 1, 2 and 3 treated with pulverized oyster shells were: 57.78 %, 31.17 % and 15.36 % and those of samples 4, 5 and 6 treated with pulverized snail shell were: 47.55 %, 26.86 % and 14.00 % respectively. Generally, the oyster shells showed a better percentage reduction of petroleum hydrocarbons than snail shells. The results also confirmed that pulverized oyster and pulverized snail shells can be employed for remediation of hydrocarbon contaminated soils

USE OF PULVERIZED OYSTER AND SNAIL SHELLS IN THE REMOVAL OF HEAVY METALS FROM HYDROCARBON CONTAMINATED SOILS

Oyster and Snail shells were used as adsorbents for the removal of heavy metals from an oil spill contaminated soil from Eneka Community in Obio-Akpor Local Government Area. Atomic Absorption Spectrophotometer was used to determine heavy metals concentrations in each of the seven soil samples before and after treatment with the pulverized oyster and snail shells. Results of the heavy metals in soil samples (A, B and C) before treatment were: Ni: 2.27 – 4.53 mg/kg (control sample 3.75 mg/kg); Cr: 48.80 – 58.10 mg/kg (control sample 47.70 mg/kg); Zn: 13.40 – 19.40 mg/kg (control sample 17.34), after treatment with pulverized Oyster shells (A1, B1 and C1) were in the range Ni: 1.31 – 3.54 mg/kg; Cr: 36.3 – 48.40mg/kg; Zn: 9.87 – 12.60mg/kg. Results of samples D, E and F before treatment with pulverized snail shell were: Ni: 1.70 – 3.97 mg/kg (control sample 3.61 kg/kg); Cr: 50.70 – 57.40 mg/kg (control sample 48.60 mg/kg); Zn: 10.90 – 20.10 mg/kg (control sample 17.50 mg/kg); after treatment with pulverized snail shell D1, E1 and F1 showed results as Ni: 1.05 – 3.59 mg/kg; Cr: 35.80 – 53.91 mg/kg; Zn: 8.43 – 16.44 mg/kg. However, the concentrations of Cadmium, Copper, Lead and Vanadium in the contaminated soil samples were below the equipment detection limit. The percentage reduction of metals in samples A, B and C treated with pulverized Oyster shells were: Ni: 42.29%, 33.55%, 21.85%; Cr: 37.52%, 19.06%, 5.47%; Zinc: 49.12%, 23.88%, 18.18% respectively. While the percentage reduction in concentration of metals in soil treated with pulverized snail shell D, E, F were: Ni: 38.24%, 21.11%, 9.57%; Cr: 29.39%, 12.72%, 6.08%, Zn: 31.84%, 22.66%, 15.69% respectively. Generally, the pulverized oyster shells showed a better percentage reduction than pulverized snail shells. The results also confirmed that both the pulverized oyster and snail shells can be employed for remediation of heavy metals in hydrocarbon contaminated soils

Bioaccumulation of heavy metals in two matrices of the Bonny/New Calabar River Estuary in Niger Delta, Nigeria

The concentrations of Ca, Mg, K, Zn, Pb, Cd, Co, Cr, Cu, Fe, Ni and Na were determined in the sediment and biota of the Bonny/New Calabar River Estuary in Niger Delta, Nigeria using atomic absorption spectrophotometer A-100. The concentration of the respective metals varied between 2011 and 2012. The range of mean values are presented in mg/kg along with variations at a statistically significant level (P< 0.05). In sediment, only Cr varied significantly (p< 0.05) within the two years. Bioaccumulation factor (BF) indicated a more potent source of metals from sediment than biota, accumulating Zn, Fe and Ni in magnitudes 10, 6 and 5 times more, respectively. The study shows elevated levels of heavy metals in sediment and bioaccumulation in biota. Regular monitoring and comparison of results with World Health Organization maximum permissible limits should be carried out, in order not to allow the metal concentration to reach alarming levels