Federal Environmental Protection Agency Research Articles

Assessment of the Impact of Untreated Rubber Effluent on the Base Cationic and Mycological Properties of Rubber Plantation Soil in Calabar, Nigeria

The study was carried out to determine the impact of rubber effluent on the cationic and mycological properties of soil in a rubber plantation through which it flows. Rubber effluent samples were collected for physicochemical and mycological analysis from the effluent discharge point of a rubber factory in Calabar, Nigeria. Three impact points (25 metres apart) were created along the flow channel of the effluent, and three sample points spaced 5m apart were created on both sides of each impact point. Top and subsoil samples were collected from the impact points and sample points for base cationic and mycological analysis. A control soil sample was also collected similarly. Correlation analysis, single-sample and two-sample were used to analyse the results. Results revealed that only temperature (26°C), sulphate (20.15 mg/l) and chloride (43.87 mg/l) conformed to Federal Environmental Protection Agency (FEPA) permissible limits of 40°C, 500 mg/l and 600mg/l, respectively. Bacteria isolated from the rubber effluent were identified as Pseudomonas spp, Micrococcus spp, Staphylococus spp, Proteus spp, Klebsiella spp, Bacillus spp, Escherichia coli, Enterobacter spp and Aeromonas spp. Fungi isolated were identified as Aspergillus spp, Penicillium spp, Rhizopus spp, Mucor spp and Sporothrix spp. Results also revealed that the rubber effluent impacted the soil, but parameters still recorded low values, as the effects of the effluent on the soil were altered by leaching, erosion and rubber root uptake. The study also revealed that microbiological investigation involving the use of a selective substrate can be used to augment or properly interpret results obtained from base cation studies similar to the current study, especially in a situation where pollution is not obvious or where factors like root uptake, leaching and erosion can potentially affect statistical results of base cation analysis.

NESREA and the Challenge of Enforcing the Provisions of Environmental Impact Assessment Act in Nigeria

Environmental Impact Assessment is a tool in ensuring environmental protection. Projects which impact the environment significantly are assessed with the aim of predicting the consequences as well as identifying appropriate measures for minimizing the adverse effects the project may have on people and their property as well as the environment. The Environmental Assessment Act, 1992 while providing details as to environmental assessment, makes for the enforcement of the stipulations in the Act through an Agency. Formerly known as Federal Environmental Protection Agency (FEPA) (created under the repealed Federal Environmental Protection Agency (FEPA) Act), the National Environmental Standards, Enforcement Agency (NESREA) (created under the National Environmental Standards, Enforcement Agency (NESREA) Act), is the Agency charged with the responsibilities of enforcing all provisions of Environmental Impact Assessment Act, in Nigeria. This research work is on the challenges as faced by the regulator i.e. NESREA in enforcing the provisions of environmental impact assessment. The work defines environmental impact assessment as well as outlines the role and function of Environmental assessment. The work looks in brief the international provisions for environmental assessment as well as environmental impact assessment in Nigeria. NESREA as the regulator is ex-rayed as to the enforcement of Environmental Impact Assessment in Nigeria. The doctrinal research methodology was employed in writing this paper. The paper identifies several challenges faced by NESREA and makes recommendations as to capacity building, infrastructure, funding, increase sanctions and penalties amongst others.

On the Modeling of Carbon Monoxide Flaring in Nigeria

Data on pollutant emissions in Nigeria were collected across the states to detect any significant change which may cause harm to human health and the environment at large. Three theoretical distributions; Weibull, Log-normal and Gamma distributions were examined on the gas flaring (carbon monoxide) observations to determine the best distribution for the pollutant emissions. The characteristics of the pollutant emissions were obtained and the probabilities of exceeding the Federal Environmental Protection Agency (FEPA) acceptable limits were estimated.

Impacts of Cassava Mill Effluents in Nigeria

Cassava is the fourth largest staple food after rice, wheat and maize. Cassava is produced in the tropical and sub-tropical countries. Currently, the global production of cassava is about 215,436,496 tons. Out of these, Nigeria accounts for 20.3%, being the largest producing nation. During processing of cassava flour (Gari), three main wastes are generated including cassava mill effluents (CME), solid and gaseous emission. This paper reviews the impacts of CME in Nigeria. The study found that CME’s physicochemical quality often exceeds the limit for effluents discharge onto land and surface water as recommended by Federal Environmental Protection Agency (FEPA), Nigeria. CME alters the quality of soil and water with regard to physicochemical, heavy metal and microbial characteristics. CME can induce toxicological effects on the environments and its biota including humans, fisheries, flora and fauna. The impacts are mostly associated with physicochemical (viz: odour, cyanide, acidic, dissolved oxygen, biological and chemical oxygen demand, conductivity) and heavy metals characteristics. Therefore, there is the need for treatment and sustainable management strategies of CME through biotechnological advancement.

Assessment of heavy metal content in imported and local fish and crustacean species obtained within Lagos Metropolis

Fishes are known for their abilities to concentrate heavy metals in their muscles and since they play important role in human nutrition, they need to be carefully screened to ensure that unnecessary high level of some toxic trace metals are not being transfer to man through their consumption. The study was to evaluate heavy metals (chromium, lead, iron and cadmium) in imported and local species of shrimps, crabs and fish using Atomic Absorption Spectroscopy. The selected imported species were horse mackerelkote fish (Trachurus trachurus), mackerel - titus (Scomber scrombus), croaker (Pseudotolithus typus), smooth swim crab (Portunus validus) and pink shrimp (Farfantepenaeus notialis) while the local species used were; Sole fish (Cynoglossus senegalensis), Tilapia (Oreochromis niloticus), brackish water catfish (Chrysichthys nigrodigitatus), freshwater catfish (Clarias gariepinus), lagoon crab (Callinectes amnicola) and freshwater prawn (Macrobrachium macrobrachion). It was observed that there was no significant difference in the metals (Cd, Pb and Cr) between the imported and local fish species and between imported and local crustacean species. However, these metals concentrated more in the local fish species, O. niloticus (1.846 ± 1.00 mg/100g). The mean heavy metals concentration occurred in the following decreasing order: Fe > Cd > Pb > Cr for all the samples. The mean concentrations of the analyzed heavy metals in the samples were below the maximum permissible limits as recommended by the International Atomic Energy Agency (IAEA), United Nations Environment Program (UNEP) and Federal Environmental Protection Agency (FEPA) for heavy metals in fish.Keywords: Fish, Shrimp, Crab, Heavy metal, Chromium, Lead, Iron

Detrimental Effects of Heavy Metals in Soil, Plants, and Aquatic Ecosystems and in Humans.

Environmental pollution has posed a major threat to flora as well as fauna for the past few decades. Industries release effluents into the environment which act as the major source of pollution. The hazardous effects of heavy metals released from these industries impact the soil and due to bioaccumulation of these compounds in the food chain, they ultimately result in a serious human health hazard. The concentration of metals like chromium (Cr), lead (Pb), nickel (Ni), cadmium (Cd), zinc (Zn), titanium (Ti), cobalt (Co), and several others in plants as well as in aquatic animals is above permissible limits according to the World Health Organization (WHO) and the Federal Environmental Protection Agency (FEPA) guidelines. This is why we need to prevent the aquatic ecosystem and human health from detrimental effects. In this review we will be discussing the harmful effects of these metals on soil, plants, aquatic ecosystems, and human health.

Biosorption of lead, chromium and cadmium in tannery effluent using indigenous microorganisms

This study investigated the biosorption of lead, chromium and cadmium in tannery effluent using indigenous microorganisms. Bacteria isolated from the tannery effluent were Bacillus subtilis and B. megaterium while fungi isolated were Aspergillus niger and Penicillium sp. The microorganisms were tested for their ability to reduce the concentration of the heavy metals in the tannery effluent using conventional methods. B. megaterium recorded the highest lead reduction (2.13 to 0.03 mg/L), followed by B. subtilis (2.13-0.04 mg/L). A. niger recorded the highest ability to reduce the concentration of chromium (1.38-0.08 mg/L) followed by Penicillium sp. (1.38 0.13 mg/L) while B. subtilis exhibited the highest ability to reduce the concentration of cadmium (0.4-0.03 mg/L) followed by B. megaterium (0.04-0.06 mg/L) after 20 days. When these values were compared to standard limits of Federal Environmental Protection Agency (FEPA), World Health Organization (WHO), National Environmental Standard and Regulations Enforcement Agency (NESREA) and Central Pollution Control Board (CPCB), the isolates recorded an acceptable reduction in the concentration of lead, chromium and cadmium in sterile and unsterile tannery effluent. The results of this showed that the isolates reduced the concentration of lead, chromium and cadmium present in the sterile and raw tannery effluent and suggest that the organisms can be used as a possible treatment of tannery effluents.

Effect of detergent surfactant on some selected electrolytes and metabolites of juvenile Heterobranchus bidorsalis

The study examined the effect of sub-lethal level of Linear Alkylbenzene Sulphonates (LAS) on some selected electrolyte and metabolic indices of juvenile Heterobranchus bidorsalis. The fish were exposed to varying concentrations of LAS (0.00 mg/L, 0.01 mg/L, 0.02 mg/L and 0.03 mg/L, respectively) in a semi-static tank for 14 days. The chemical test analysis of LAS showed that only total suspended solid (196.8 mg/L), total alkalinity (56.1 mg/L) and nitrate (7.9 mg/L) exceeded Federal Environmental Protection Agency (FEPA) and Standard Organization of Nigeria (SON) permissible limits. Conductivity and dissolved oxygen (DO) of the water parameter differ significantly (p < 0.05) from the control and among dose concentration. Electrolyte values (K+ and Ca2+) were not significantly (p > 0.05) different at all level of LAS concentration. However, there were significant (p < 0.05) differences in Na+ concentration. The highest value for Na+ (16.00 + 1.16 Mmol/L) was obtained at 0.02 mg/L, while the least (5.35 + 0.45 Mmol/L) was recorded in the control at 0.00 mg/L. There was significant (p < 0.05) differences in values of urea in the experimental group, except between 0.01mg/L (1.53 + 0.05 mg/dm) and 0.02 mg/L (1.60 + 0.06 mg/dm). On the contrary, there were significant (p < 0.05) differences in all the values of creatinine recorded in this study. The values increased down the experimental group in a dose dependent pattern. The highest value of creatinine (54.45 + 4.96 mg/dm) was recorded at 0.03 mg/L dose concentration while the least (30.47 + 7.65 mg/dm) was obtained in the control (0.00 mg/L). The present study concluded that LAS has impact on the metabolites and electrolytes especially creatinine and the Na+. Therefore, LAS could be very toxic at high concentrations and as such, indiscriminate discharge of LAS effluent into aquatic environment should be averted.

Biochemical Effects of the Toxic Interaction of Copper, Lead and Cadmium on Clarias gariepinus.

Background.The presence of heavy metals in the aquatic environment is a concern because of potential toxicity and threats to plant and animal life.Objective.The present study evaluated the joint action toxicity and biochemical effects of sublethal concentrations of copper (Cu), lead (Pb) and cadmium (Cd) against Clarias gariepinus over a period of 28 days.Methods.We procured fingerlings (weight: 5–8 g; length: 4.5–6.0 cm) and juveniles (weight: 20–25 g; length: 14.5–17.5 cm) from a commercial fish farm in Bariga, Lagos state, Nigeria. Test toxicants were selected from the analyzed heavy metals in the field based on their deviation from World Health Organization, Federal Environmental Protection Agency and United States Environmental Protection Agency standards. Fish were randomly loaded into a 4-L glass aquaria for the bioassay per toxicant concentration of two replicates and untreated control (dechlorinated tap water).Results.The derived 96 hour lethal concentration 50 (LC50) value of Cu (2.11 mg/L) was the most toxic followed by Cd (24.18 mg/L) and Pb (34.48 mg/L), which was the least toxic of the singly tested pollutants. The analysis of dose-response data of the joint action toxicity of Cu and Cd, and Cu and Pb determined 96 hour LC50 values of 1.804 mg/L and 2.15 mg/L, respectively. The interactions between the mixture of Cu:Cd conformed with the model of synergism (synergistic ratio (SR)>1 and relative toxic units (RTU)>1), while the interaction between Cu:Pb was found to be antagonistic (SR<1), with an SR value of 0.98. The biochemical effects study revealed that malondialdehyde (MDA) levels decreased significantly (P<0.05) in the exposed fish, reduced glutathione was not significant at (P<0.05), and levels of superoxide dismutase (SOD), catalase, glucose and cholesterol were significantly different (P<0.05).Discussion.The observed increased in the glutathione level in the Cu:Cd mixture and a corresponding decrease in MDA concentration in the liver of test animals revealed the ability of fish to overcome the effects of lipid peroxidation in this group because the Cu ion is displaced by Cd, and the fish were able to catalyze the breakdown of hydrogen peroxide via the Fenton reaction.Conclusions.Further studies on the joint action toxicity of heavy metals are needed in order to further determine their concentration in the local environment.Ethics Approval.Study protocols were approved by the Health Research Ethics Committee of the University of Lagos.

Biodegradation Potentials of Cassava Mill Effluent (CME) by Indigenous Microorganisms

The indiscriminate discharge of Cassava mill effluent pose serious environmental and public health implications. This work was aimed at assessing the biodegradation potentials of indigenous microbial isolates from cassava mill effluent using screening and shake flask degradation tests. The mean heterotrophic bacterial and fungal counts were 3.4±0.26 x 106cfu/ml and 1.1±0.20 x 106cfu/ml respectively. The microorganisms isolated, characterized and identified include the genus Pseudomonas (15.48%), Bacillus (12.41%), Acetobacter and Rhizopus (10.88%), Corynebacterium (9.33%), Lactobacillus, Micrococcus and Aspergillus (7.79%), Staphylococcus and Penicillium (6.25%) and Saccharomyces species (4.62%). The pH (5.39 ± 0.14), electrical conductivity (2506.90 ± 45.35), sulphate (210.87 ± 5.31), nitrate (365.28 ± 3.61), phosphate (107.70 ± 2.10), cyanide (19.93 ± 0.25), chemical oxygen demand (1728.33 ± 19.66), biological oxygen demand (1141.51 ± 12.69), iron (206.43±2.05), zinc (54.56 ± 0.62), manganese (19.96 ± 0.35), copper (10.67 ± 0.10) and nickel (3.28 ± 0.46) in mg/l were above the Federal Environmental Protection Agency standard for effluent discharge. Bacillus, Pseudomonas, Aspergillus and Penicillium species which had the highest turbidity were used for bioremediation studies. The consortium of microorganisms demonstrated the highest efficacy. Bioremediation of cassava mill effluent by these microorganisms was manifested in the reduction of biological oxygen demand (consortium of Pseudomonas and Bacillus species 97.42%), (Aspergillus and Penicillium species 75.32%) and chemical oxygen demand (Pseudomonas and Bacillus species 37.63%), (Aspergillus and Penicillium species 44.97%). The study has shown that microbial isolates have the potentials of reducing pollution effect thereby enhancing management of cassava mill effluent before eventual discharge into the environment.Keywords: Biodegradation, Environmental management, Microorganisms, Turbidity, Cassava mill effluent, Ebelle.

Biotreatment of effluent from 'Adire' textile factories in Ibadan, Nigeria.

In this present study, bacteria were isolated from wastewater and polluted soil collected from two cottage textile factories in Ibadan. These bacteria isolates were used for the biotreatment of textile mill effluent. The physicochemical parameters of the textile mill effluent before treatment were carried out and percentage decolourisation of the effluent was analysed using ultraviolet-visible spectroscopy (UV-vis technique). The degradation products of the textile mill effluent characterised by Fourier transform infrared spectroscopy (FTIR). The pH values of the effluent were within the permissible limit of Federal Environmental Protection Agency (FEPA) and National Environmental Standards and Regulations Enforcement Agency (NESREA), while temperature and electric conductivity of the effluents were below the permissible limit of FEPA and NESREA. The BOD, COD, TSS, TDS and chloride of the textile mill effluent from the two cottage textile factories were above the permissible limits of FEPA and NESREA. Twelve bacteria isolates were screened, effective in decolourising commercial dyes and used to decolourise the textile mill effluent. The bacteria isolates were characterised and identified as Bacillus sp., Micrococcus sp., Erwinia sp., Acinetobacter sp. and Nocardia sp. The decolourisation of textile effluent was observed through the changes of spectra of UV-visible spectrophotometer. The following bacteria revealed different percentage proportion of decolouration profile:- Bacillus sp., had the highest percentage decolourisation of 57.7%, whereas Micrococcus sp. and Acinetobacter sp. had percentage decolourisation of 32.8 and 26.3%, respectively. The degradation profile of textile effluent was revealed through FTIR spectral analysis. The changes in the position of major peaks revealed from the textile effluent through FTIR spectral analysis, appearances of new peaks and the disappearances of existing peaks signify the degradation of the wastewater. Thus, some native microorganisms from the textile effluent could be enhanced to effectively degrade effluent from such environments.

Distribution, pollution index and associated health risk of trace metals in waste-impacted soils within Akwa Ibom State, Nigeria

This research assessed the level, source and associated health risks of trace metals in waste-impacted soils within Nigeria. Results reported revealed that mean concentrations for all the metals studied were higher than their levels in control. The mean concentrations of all the metals except Ni were also higher than their recommended limits for Nigerian soil by Federal Environmental Protection Agency. Pollution assessment of these trace metals and different locations studied indicated that Pb and Cd were metals with very high contamination status. Results obtained indicated that concentrations of Fe and Ni were mainly from natural geological processes while Pb, Cd and Cu were from anthropogenic source. Principal component analysis revealed human activities as the major factor for the presence of these metals at the different locations studied. This study identified Ibeno and Uyo as locations with very high soil contamination. Hierarchical clusters and Pearson correlation analyses showed variable relationship among the different locations and metals studied. Results obtained indicated that children in Ibeno and Uyo are in a very high risk developing health problems associated with Pb and Cd. The analytical procedures and results obtained were validated using SRM 2710a (Montan 1 soil.) from NIST, U.S.A.

Lithological Identification and Underground Water Conditions in Jeddo Using Geophysical and Geochemical Methods

Resistivity soundings and hydrogeochemical methods were carried out in order to establish the characteristics of the aquifer in Jeddo, Southern Nigeria. Results of the resistivity sounding revealed that the formation is made up of clay, clayey sand, and fine- to coarse-grained sand. The mean depth of the aquifer was obtained as 12.7 m while the aquifer resistivity ranged from 161 to 1728 Ωm. The mean value of transmissivity obtained for the aquifer is 169 m2 day−1 while analysis of the transmissivity revealed that about 6% of the study area has greatest potential for a productive aquifer. The study also revealed that the underground water flows in the northeast–southwest direction. The hydro geochemical analysis of water samples showed that some parameters such as lead, color and pH exceeded the permissible limits, which were established by Federal Environmental Protection Agency and the World Health Organization. It is concluded from the water quality index (WQI) that the groundwater is of poor quality and requires some remediation before it can be used for domestic and industrial purposes.

Toxic and essential metals in Cyprinus carpio, Carassius gibelio, and Luciobarbus esocinus tissues from Keban Dam Lake, Pertek, Turkey

ABSTRACTIn various tissues of Luciobarbus esocinus, Cyprinus carpio, and Carassius gibelio which were taken from Keban Dam Lake Pertek region’s freshwaters, Turkey in January–February 2016, concentrations of mercury, nickel, lead, cadmium, arsenic, manganese, chromium, and cobalt were analysed by inductively coupled plasma-mass spectrometry (ICP-MS) after microwave digestion. In fish muscle mean chromium concentration (0.614 mg kg−1 in C. carpio muscle) was higher than the maximum limits as set by the Federal Environmental Protection Agency and World Health Organisation. Additionally, mean concentration of lead (0.380 mg kg−1 in C. gibelio muscle) was higher compared to the maximum limit as set by Turkish Standards. Furthermore, in the assessment of the potential health risk, estimated weekly and daily intake of all metals were considerably below permissible tolerable weekly intake (PTWI) and permissible tolerable daily intake values. As a result, consumption of these fish species from this region does not pose a problem on human health.

Physicochemical properties of a flowing stream in Jabi, Abuja, Nigeria

The physicochemical qualities of flowing stream located in Jabi, Abuja, Nigeria was assessed over the duration of 3 months. Parameters measured include pH, temperature, electrical conductivity, turbidity, biological oxygen demand (BOD), dissolved oxygen, chemical oxygen demand, nitrate, sulphate, acidity, alkalinity, and carbon levels and these were simultaneously monitored in the flowing stream using standard methods. Unacceptably, high levels of the assayed parameters were observed in Nitrate (1.39 to 1.44 mg/L), while dissolved oxygen (3.2 to 11.6 mg/L) and turbidity (8.6 to 9.1 NTU) were totally outside the compliance levels of the Federal Environmental Protection Agency (FEPA) Guidelines and World Health Organization (WHO) tolerance limits for domestic uses. The study has revealed that there was an adverse impact on the physiochemical characteristics of the flowing stream as a result of discharge of inadequately treated waste products from surrounding communities. This poses a health risk to several rural communities which rely on flowing stream primarily as their sources of domestic water and also harmful to aquatic life. There is need for the intervention of appropriate regulatory agencies to ensure flowing stream is hygienic for consumption and aquatic life through proper channelling.

Public health impacts of excess NOx emissions from Volkswagen diesel passenger vehicles in Germany

In September 2015, the Volkswagen Group (VW) admitted the use of ‘defeat devices’ designed to lower emissions measured during VW vehicle testing for regulatory purposes. Globally, 11 million cars sold between 2008 and 2015 are affected, including about 2.6 million in Germany. On-road emissions tests have yielded mean on-road NOx emissions for these cars of 0.85 g km−1, over four times the applicable European limit of 0.18 g km−1. This study estimates the human health impacts and costs associated with excess emissions from VW cars driven in Germany. A distribution of on-road emissions factors is derived from existing measurements and combined with sales data and a vehicle fleet model to estimate total excess NOx emissions. These emissions are distributed on a 25 by 28 km grid covering Europe, using the German Federal Environmental Protection Agency’s (UBA) estimate of the spatial distribution of NOx emissions from passenger cars in Germany. We use the GEOS-Chem chemistry-transport model to predict the corresponding increase in population exposure to fine particulate matter and ozone in the European Union, Switzerland, and Norway, and a set of concentration-response functions to estimate mortality outcomes in terms of early deaths and of life-years lost. Integrated over the sales period (2008–2015), we estimate median mortality impacts from VW excess emissions in Germany to be 1200 premature deaths in Europe, corresponding to 13 000 life-years lost and 1.9 billion EUR in costs associated with life-years lost. Approximately 60% of mortality costs occur outside Germany. For the current fleet, we estimate that if on-road emissions for all affected VW vehicles in Germany are reduced to the applicable European emission standard by the end of 2017, this would avert 29 000 life-years lost and 4.1 billion 2015 EUR in health costs (median estimates) relative to a counterfactual case with no recall.

Bioremediation of Total Soluble Salt of Tannery Effluent Using Halophilic Microbial Consortium

Tannery effluent is known to contain large amount of dissolved salt (such as NaCl) used in the preliminary preservation of hides and skin, which is known to be highly soluble and stable in nature, difficult to eliminate and toxic in nature, thereby being a burden to the environment (ecosystem) and human health. The aim of this study is to isolate halophilic organisms from Nigerian Institute of Leather and Science Technology, Zaria tannery dumpsite using selective media. The isolated microbes were characterized microscopically and biochemically using standard methods. The microbes isolated include; Staphylococcus aureus, Bacillus sp, Pseudomonas aeruginosa, and Saccharomyces cerevisiae. The isolates were used for the bioremediation of total soluble salt in the tannery effluent. Before the tannery effluent treatment, physicochemical parameters such as temperature, pH, colour, Biochemical Oxygen Demand (BOD), Chemical Oxygen Demand (COD), chloride content, conductivity, total dissolved solid (TDS) and salinity were determined using standard procedures. The bioremediation of tannery effluent was carried out using the isolated organisms individually and in combination. The highest remediation was observed in the combination of microbial consortium, followed by Saccharomyces cerevisiae, Staphylococcus aureus, Pseudomonas aeruginosa and Bacillus sp. The temperature of the effluent ranges between 27.4°C to 27.6°C before the bioremediation, which increased to between 28.4°C and 32.3°C after remediation. Majority of the physicochemical parameters analyzed recorded drastic decrease especially the salinity (7.10 ppt to 1011 ppm), conductivity (1788 µS to 1407 mS), colour (faint ash to ash), BOD (942 mg/l to 1156 mg/l), COD (1239 mg/l to 508 mg/l), chloride content (181.9 mg/l to 579.8 mg/l), pH (6.3 to 9.1) and TDS (8.20 ppt to 1322 ppm) respectively. Most of the physicochemical parameters are above the Federal Environmental Protection Agency (FEPA) and Ethiopian Environmental Protection Authority (EEPA) standard safe limit viz; pH (6.9), Conductivity (2500 µScm−¹), BOD5 (50 mg/l and 200 mg/l), COD (500 mg/l). However, temperature (<40 and 40°C) and chloride content (1000 mg/l and 600 mg/l) are within the acceptable limits. Also, there is significant difference (P= 0.000 at 0.005 level of significance) between the chloride content of the tannery effluent before the bioremediation and the chloride content after ten days bioremediation. Thus, it is recommended to use these organisms in combination to remedy total dissolved salt efficiently than in single. Halophiles can be used in bioremediation of total soluble salt in tannery effluent. It is recommended that natural halophilic microbes should be used in the remediation of total soluble salts in preference to chemicals, which may contain heavy metals that cause toxicity and threat to the environment (ecosystem) and human health.

Heavy metal pollution of aquatic systems in oil producing communities of delta state, Nigeria

Objective: This study was designed to determine the heavy metal pollution status of some rivers and creeks within oil producing communities in Delta state of Nigeria. Methodology and Results: Water and fish samples were collected from six Rivers in Delta state viz: Egbokodo River in Warri, River Ethiope in Sapele, Urie River in Igbide Isoko, Asaba-Ase creek, Aragba River in Abraka, and Uzere Creek. Water fresh, and ready to eat fish samples were analyzed for heavy metals (lead, cadmium, manganese, copper, iron and nickel) levels. Most heavy metals were marginally below the residual level recommended by the World health organisation (WHO) and Federal Environmental Protection Agency (FEPA). Iron cadmium and Nickel were detected in all samples irrespective of the site of collection. Nickel exceeded the WHO standard limit (0.6) in fresh fish samples from Aragba (0.89) and Asaba-Ase (0.7), while fresh fish sample from Ethiope river had marginally higher Manganese concentrations (0.57) than recommended by WHO (0.5) Conclusion and application of results: Fish from each of these rivers were marginally safe in their concentration of the studied metals. Caution and constant monitoring to prevent increased concentration and to the aquatic fauna and resultant toxicity to human consumers through the trophic web is important. Further investigation and routine monitoring will enable optimal recommendations and policies for surface water and fauna monitoring of the Niger Delta region in Nigeria. Keywords: Heavy metals; Pollution; fish; Delta state; Nigeria

Treatment of landfill leachate using Solar UV facilitated photocatalytic degradation

The use of heterogeneous photocatalytic degradation for the treatment of landfill leachate was investigated in this study. The photocatalytic degradation studies were carried out using Zinc oxide (ZnO) as photocatalyst and the process was facilitated by ultra violet radiation (UV) from sunlight. Characterisation of the raw leachate revealed that its physicochemical properties did not meet the requirements set by the Federal Environmental Protection Agency (FEPA) thus necessitating the need for the treatment. Results obtained showed that there was a significant reduction in biochemical oxygen demand (BOD) (85.6%), turbidity (82.5%) and heavy metals (~100%) as well as a significant increase in the dissolved oxygen (DO) (85.2%) of the treated leachate. Increasing the contact time favoured the degradation process while higher loading of ZnO enhanced the process too. The physico-chemical characteristics of the treated leachate were within the limits set by FEPA suggesting that the treated leachate could be safely discharged into natural water bodies without fear of it causing any deleterious effect on the ecosystem. Keywords: Leachate, Adsorption, Zinc oxide, Biochemical oxygen demand, Turbidity

English

A study was conducted to characterize Modjo tannery effluent (wastewater) and determine its impact on the Modjo River using some physicochemical parameters. Accordingly, three tannery wastewater samples along wastewater channel at different distances have been taken and three river water samples (one upstream and two downstream) were collected along the river to determine its impact on the river. The samples have been analyzed for temperature, pH, electrical conductivity (EC), total dissolved solids (TDS), total suspended solid (TSS), chloride(Cl-), biological oxygen demand (BOD5), chemical oxygen demand (COD), total ammonia (as N), total nitrogen, total phosphorus and sulphide. The result of tannery wastewater showed that the values of temperature, pH, EC, TDS, TSS, Cl-, BOD5, COD, total ammonia, total nitrogen, total phosphorus and sulphide along the wastewater channel ranged from 26.97 to 24.93&deg;C, 9.33 to 8.33, 15670.00 to 14496.67 mgL-1, 9370.00 to 8723.33 mgL-1, 4979.33 to 2647.67 mgL-1, 6111.67 to 5555.78 mgL-1&nbsp; 960.34 to 842.00 mgL-1, 2011.00 to 1950.75 mgL-1, 520.44 to 401.23 mgL-1, 720.46 to 665.43 mgL-1, 30.12 to 19.55 mgL-1 and 35.56 to 21.05 mgL-1 respectively. And most of the effluent characteristics except pH and temperature were beyond the provisional discharge limit of tannery effluent to water body set by the Ethiopian Environmental Protection Authority (EEPA) and Federal Environmental Protection Agency (FEPA). Analysis of variance (ANOVA) also showed that variation among sampling points were statistically significant (p&lt;0.5). Similarly, the levels of all these physicochemical parameters in the downstream site of the river were higher as compared to the values obtained from the upstream site (control). This indicated that the downstream site of the river is polluted as a result of the direct discharge of the tannery effluent to it. Key words: Modjo tannery, Modjo River, wastewater, physicochemical parameters, water pollution.