National Environmental Standards And Regulations Enforcement Agency Research Articles

CORRELATION ANALYSIS AND MODELLING OF HEAVY METAL CONCENTRATIONS AND PHYSICOCHEMICAL PARAMETERS FROM SOIL SAMPLES OF FIVE SELECTED REFUSE DUMPSITES IN LAFIA LOCAL GOVERNMENT AREA OF NASARAWA STATE, NIGERIA

Thousands of tons of solid wastes are generated and disposed daily in open dumps of most Nigerian cities due to rapid population explosion and commercial activities. In this study, concentrations of heavy metals and physicochemical parameters from 20 soil samples each from selected refuse dumpsites in wet and dry seasons were determined using Atomic Absorption Spectrophotometer and Association of Official Analytical Chemists (AOAC) standard methods. The results showed that during the wet and dry seasons, the concentration of heavy metals, Hg, Cr, Mn were above that of World Health Organisation (WHO), and National Environmental Standards and Regulations Enforcement Agency (NESREA), while that of Pb, As, Fe, Zn, Cu and Ni were below the tolerable limits. The results for physicochemical parameters in wet and dry seasons for nitrates, phosphates and organic matter were above WHO standards. Statistical test at 0.05 probability level (p < 0.05) was used to determine the degree of association between pairs of the variables. The principal component analysis (PCA) was performed to measure the direct and inverse relationship between these parameters and heavy metal availability. Based on the different variables obtained at the study areas, a multiple linear regression analysis was determined from which a general linear model was formulated. The study recommends appropriate government agencies should as a matter urgency integrate the regular monitoring of waste disposal into the state developmental plan and framework in order to prevent excessive build-up of these metals in humans through the food chain.

Assessment of seasonal variations in vehicular emissions at traffic intersections in Ibadan using AERMOD dispersion model

AbstractAfrican cities grapple with urban air pollution from traffic‐related air pollutants (TRAPs). This study investigated TRAPs concentration variations at traffic intersections (TIs) in Ibadan, Nigeria. AERMOD model was employed to examine TRAPs dispersion at 25 selected TIs, considered as volume sources. Seasonal concentration distributions of six pollutants (CO, NO2, SO2, TVOCs, PM2.5, and PM10) were determined using meteorological, topographical, and pollutants’ emission rates in AERMOD. Estimated peak concentrations of the studied pollutants were generally higher in the rainy season than dry season, surpassing the air quality standards set by World Health Organization (WHO) and Nigeria's National Environmental Standards and Regulations Enforcement Agency (NESREA) during the rainy and dry seasons except SO2 (24 h) concentration which did not exceed the NESREA standard. This study highlighted TIs as significant contributors to air quality degradation in both seasons studied in Ibadan and showed AERMOD's suitability for air dispersion studies.

Solid Waste Challenges and Management in a Traditional Sahelian City: A Case Study of Sokoto, Nigeria

This study assessed the solid waste generation, management, and consequences in the traditional city of Sokoto. The utmost challenges facing this Sahel region include scarcity of modernized and control measures of waste resulting from daily hectic impacts on the community. In this city, solid waste is characterized by inefficient control, insufficient coverage of collection system and improper disposal methods. The increasing population of residents has accelerated more pollution of all categories, and the consequence is a dearth of hygienic standards. This work further sampled different materials from heaps of waste such as; the level of sub-soils at 0-30 cm (at random) from each of the dump sites to determine the extent of heavy metal concentrations and for fertility supplement in comparison with the National Environmental Standards and Regulations Enforcement Agency (NESREA). Fifty structural questionnaires were administered randomly to selected residents around dumping sites and the staff of Sokoto Waste Management &Planning Board to solicit relevant information that can assist the governments, stakeholders, and waste control agencies. Also, Landsat data was utilized to map out the waste sites for spatio-temporal analysis. Results indicated that 89% of respondents agreed that Sokoto metropolis is characterized by untidiness with masquerades of biodegradable wastes, while major streets especially in the congested areas which displayed a lot of drains and channels remain blocked.

Status of Selected Heavy Metals in Soils Samples Obtained From Crown Estate Dumpsite, Okada, Edo State, Nigeria

This research work focused on the status of selected heavy metals in dumpsite soil compared with soil samples obtained from a green park area as a control. The research results were also related to threshold limits set by the National Environmental Standards and Regulations Enforcement Agency (NESREA), World Health Organization (WHO) and Food and Agriculture Organization (FAO). Soil samples were collected from a dumpsite inside Crown Estate (made up of residential quarters for both staff and students of Igbinedion University) and a green area of Igbinedion University's permanent site, Okada, Benin City, Edo State in Nigeria. The soil samples were air-dried, ground, sieved, digested and subjected to heavy metal analysis using atomic absorption spectroscopy. The analyzed metal profiles in the dumpsite soil samples are as follows: concentration of Fe, Pb, Cu, Zn, Mn and Ni ranged from 453.26 – 569.28, 0.85 – 1.16, 20.17 – 32.35, 60.98 – 74.26, 5.15 – 9.28, and 5.92 – 9.57 mg/Kg, with mean concentrations of 501.33 mg/Kg, 0.96 mg/Kg, 25.38 mg/Kg, 66.33 mg/Kg, 6.89mg/Kg and 7.90 mg/Kg respectfully, while the status of heavy metal concentration in soil samples collected from the control site ranged from 386.21 – 463.95, 0.82 – 1.32, 20.05 – 26.27, 47.75 – 65.22, 5.77 – 8.73, and 6.35 – 9.87 mg/Kg, with mean concentration of 401.76 mg/Kg, 1.05 mg/Kg, 23.05 mg/Kg, 54.84, 7.39 mg/Kg and 7.78 mg/Kg for Fe, Pb, Cu, Zn, Mn and Ni respectfully. Of all the metals analyzed only the level of Fe in this study did exceed the tolerance limits of NESREA, WHO and FAO. The results also revealed higher heavy metal content in the dumpsite justifiably due to the difference in anthropogenic activities carried out on the two sites.

Evaluation of heavy metals in soil from automobile mechanic Village Dutse, Jigawa State, Nigeria

Soil contamination by heavy metals is a worldwide environmental problem. Some heavy metals pollutants are released from the activities in the auto-mechanic workshops and have various effects on human health as well as the environment. It is important to determine the presence and concentration level of the heavy metals in the soil. This research was aimed to determine the level of some selected heavy metals and physicochemical parameters of the soil sample. The soil samples were digested with nitric and hydrochloric acid and heavy metals were analyzed from digested samples using atomic absorption spectrometer (AAS). Results of the atomic absorption spectrophotometric (AAS) analysis of soil samples revealed that sample is contaminated with Ni, Zn, Mn, Fe and Cu with concentrations level (mg/kg) range between (0.75 - 5.55), (0.30 - 0.40), (1.00 -1.42) (0.80 - 1.30) and (0.05 - 0.60), respectively. Other metals such as As, Cd, Cr also contaminated the soil with concentrations (mg/kg) ranged between (0.12-0.76), (0.13-01.13) and (0.11-1.30), respectively. The results were compared with the standard set by National Environmental Standards and Regulations Enforcement Agency (NESREA). The research concluded that the anthropogenic activities at auto-mobile workshops contaminate soil with heavy metals which may have a direct or indirect effect on human. Further studies should be conducted to ascertain the effects of those metals on human, plants, groundwater, and environment.

Assessment of Transient and Spatial Noise Pollution Levels at Selected Junctions in Port Harcourt Metropolis, Rivers State

This study focused on assessing of transient and spatial noise levels at selected Port Harcourt Metropolis junctions. Spatial noise measurement and vehicle count were conducted at Eleme and Akpajo junctions. Comparative analyses of noise level and noise pollution level using line graph/t-test and determination of decline rate of noise pollution level using regression analysis were carried out. Comparative analyses of noise levels at the two study locations using traffic count were also done. The noise pollution level was compared with National Environmental Standards and Regulations Enforcement Agency (NESREA) and World Health Organization (WHO) noise standards and a safe zone determined at study locations. Maximum and minimum noise recorded were 88.99dB(A) and 50.05dB(A) at Eleme junction, 87.51dB(A) and 49.02dB(A) at Akpajo junction. Findings showed that the noise pollution level was relatively higher than noise level with distance away from the junctions; however, there was no significant difference between noise level and noise pollution level. Maximum noise pollution level average decline rate of -0.3691dB was observed at Eleme junction in the morning, while the minimum noise pollution level average decline rate of -0.2656dB was observed at Akpajo junction, in the morning hours. External sources also contributed to noise level at the junctions. Those living or doing business within 100m and 120m of Akpajo and Eleme junctions, respectively are at risk of having noise-induced auditory, physiological and behavioral problems. There is need for continuous monitoring of noise level at study locations. Regular health assessment of people living within the study locations. Noise control regulations should be made and enforced by the Government.

Measurement and Analysis of Noise Levels: A Study of Selected Pubs in Calabar, Nigeria

This research involves the assessment of noise levels in pubs operating in Calabar, Nigeria, to investigate their compliance with the permissible noise level recommended by the National Environmental Standards and Regulations Enforcement Agency (NESREA), Nigeria. A Bam and Kom (BK) Precision 732 digital sound level meter placed on a tripod was used for the measurement of noise levels for three consecutive months, from 6:00pm to 10:00pm. The measured data were subjected to descriptive statistics using excel spreadsheet and the results were presented in the forms of graphs, bar chart and in tabular form. Average equivalent noise level obtained for pubs A, B, C, D and E were 86.5dB, 75.7dB, 75.9dB, 90.0dB and 81.9dB, respectively. Results show that all the pubs under study were in excess of the permissible noise level recommended by NESREA.

Measurement and Analysis of Noise Levels: A Study of Selected Pubs in Calabar, Nigeria

This research involves the assessment of noise levels in pubs operating in Calabar, Nigeria, to investigate their compliance with the permissible noise level recommended by the National Environmental Standards and Regulations Enforcement Agency (NESREA), Nigeria. A Bam and Kom (BK) Precision 732 digital sound level meter placed on a tripod was used for the measurement of noise levels for three consecutive months, from 6:00pm to 10:00pm. The measured data were subjected to descriptive statistics using excel spreadsheet and the results were presented in the forms of graphs, bar chart and in tabular form. Average equivalent noise level obtained for pubs A, B, C, D and E were 86.5dB, 75.7dB, 75.9dB, 90.0dB and 81.9dB, respectively. Results show that all the pubs under study were in excess of the permissible noise level recommended by NESREA.

Evaluation and spatial noise mapping using geographical information system (GIS): A case study in Zaria city, Kaduna State, Nigeria

Background: Spatial noise level mapping using a geographical information system (GIS) is essential for the visual colour representation of noise analysis, which is a necessity for strategic planning and mitigating measures. Methods: Extech noise meter (model 407750) was used for sound measurement and a GIS (inverse distance weighted) was used in 54 study locations for the spatial interpolation. The study was classified into five categories based on Nigeria’s WHO standard and National Environmental Standards and Regulations Enforcement Agency (NESREA). Results: For the LDAY (D),LEvening (E), LNight (N), and LDEN, all the locations exceeded the WHO standard while 94.4%, 90.7%, 83.3%, and 83.3% of the locations exceeded the NESREA standard. The LDay (D) ranged from the minimum value of 67.6 dB (A) at the Ijaw residential area to the maximum value of 93.0 dB (A) at Kwangila site (1) intersection. The LNight ranged from the minimum value of 63.3 dB (A) at Dogorawa residential area to the maximum value of 92.1 dB (A) at Kwangila site (1). The LDEN ranged from the minimum value of 73.1 dB (A) at Hanwa residential areas to the maximum value of 97.2 dB (A) at Kwangila site (1). The noise quality rating ranged from satisfactory to unallowed noise quality grading. The selected intersections and residential areas with light commercial activities had the highest and lowest noise levels, respectively. Conclusion: Efficient maintenance of silencers, planting trees with dense foliage, and strategic planning would be necessary panacea in curbing excessive noise.

The Chemistry and Health Outcomes of Electronic Waste (E-Waste) Leachate: Exposure to E-Waste Is Toxic to Atlantic Killifish (Fundulus heteroclitus) Embryos

Although there is rising global concern over the environmental, ecological, and human health risks associated with the discharge of leachates from e-waste dumpsites into the aquatic ecosystems, little is known in this research area. Thus, for this study, we first defined the chemistry of the test leachate, followed by assessment of the leachate on the development of a model aquatic organism (Fundulus heteroclitus) used extensively as a bioassay organism in pollution studies. Chemical analyses revealed that levels of phosphate (20.03 mg/L), cadmium (Cd) (0.4 mg/L), lead (Pb) (0.2 mg/L), and chromium (Cr) (0.4 mg/L) were higher than the 2009 US EPA and the 2009 National Environmental Standards and Regulations Enforcement Agency (NESREA) permissible limits. Polycyclic aromatic hydrocarbon (PAH) burdens were dominated mainly by the high molecular weight congeners, specifically the ∑4rings (73 µg/L). Total polychlorinated biphenyls (PCB) levels ranged from 0.00 to 0.40 µg/L with the ∑deca PCBs reaching the highest concentration. For the biological studies, F. heteroclitus embryos (48-h post-fertilization) were divided randomly into groups and exposed to one of six e-waste leachate concentrations (10, 1, 0.1, 0.01, 0.001, 0.0001%). Significant differences (p ≤ 0.05) between treated and control groups were observed in standard and total length, and head size. Further analysis using Duncan’s post-hoc test of multiple comparison also revealed specific differences within and between specific treatment groups. We conclude that e-waste leachate arising from indiscriminate dumping into aquatic ecosystems in Nigeria contains mixtures of toxic constituents that can threaten ecosystem and public health.

Assessment of Heavy Metals and Polycyclic Aromatic Hydrocarbons in Agricultural Soils around Kubanni Bridge area, Zaria, Kaduna State, Nigeria

The level of heavy metals and polycyclic aromatic hydrocarbons (PAH) were determined from agricultural soil collected in Kubanni area of Zaria using standard methods. The result mean±SD of the heavy metals in the five study locations; (KP1- KP3) ranges from 4.05±0.18-1.25±0.32 for Lead, 4.43±0.11-0.03±0.01 for Cadmium,4.30±0.14 - 0.13±0.08 for Chromium, 3.32±0.25-1.03±0.13 for copper. And 1.80±0.01- 0.02±0.01 for Zinc. The results of the persistent organic pollutants in the five study locations KP1- KP3 showed the mean range (±SD) concentrations from7.08±0.02-0.13±0.01 (naphthalene), 7.00±0.08 - 0.02±0.01 (anthracene) and 7.31±0.21 - 0.02±0.01 (phenanthrene). There was appreciable number of heavy metals and PAH in the study area even though it was found to be below the permissible level set by United State Environmental Protection Agency (USEPA) and National Environmental Standards and Regulations Enforcement Agency (NESREA) in most of the locations. There is the tendency of these residues from the soil to accumulate into crops grown in the studied area, which can constitute serious health risk.

Investigation of environmental noise level status in Oshodi/ Isolo local government of Lagos State, Nigeria

Noise is a public nuisance which can result to adverse health effects. This work was carried out to investigate the environmental noise level status in Oshodi/Isolo Local Government of Lagos State, Nigeria. 10 different locations were selected in each of educational, industrial, traffic, commercial and residential areas which were coded EA – EJ, IA – IJ, TA – TJ, CA – CJ and RA – RJ respectively. All the chosen locations were coordinated using handheld Global Positioning System (GPS) for the purpose of universal identification. Noise level were measured in each of the selected locations using sound level meter (SLM) in the morning (7 – 9 a.m), afternoon (12 – 2 p.m) and evening (4 – 6 p.m). The results revealed that the noise level in educational areas ranged between 67.90 and 79.90 dB, between 50.70 and 72.30 dB and between 51.70 and 72.30 dB for morning, afternoon and evening respectively while the industrial areas varied between 70.20 and 77.40 dB, between 70.30 and 72.90 dB and between 70.20 and 76.40 dB for morning, afternoon and evening respectively. The noise level in traffic areas ranged between 70.80 and 90.30 dB, between 70.70 and 79.70 dB and between 67.50 and 77.90 dB for morning, afternoon and evening respectively while the commercial areas varied between 68.50 and 88.80 dB, between 73.20 and 78.90 dB and between 70.80 and 78.30 dB for morning, afternoon and evening respectively. The noise level for residential areas ranged between 68.77 and 77.20 dB, between 69.70 and 71.60 dB and between 68.20 and 72.20 dB for morning, afternoon and evening respectively. The threshold limits by National Environmental Standards and Regulations Enforcement Agency (NESREA) for noise level in educational, residential, commercial, industrial and traffic areas are 45, 50, 55, 70 and 80 dB respectively while Lagos State Environmental Protection Agency (LASEPA) threshold limits are 55, 70 and 90 dB for residential, commercial and industrial areas respectively. These indicated that the noise level in the investigated areas exceeded the NESREA and LASEPA standard limits for noise level. The analysis of variance (ANOVA) showed that at 5 percent significant level, there was no statistical difference in the mean noise level in all the investigated areas. It was concluded that Oshodi/Isolo Local Government of Lagos State was polluted and the relevant authorities need to be proactive and take urgent steps to minimize the level of noise pollution in Oshodi/Isolo Local Government of Lagos State.

Comparison of Emission Levels of Motor Cars, Motorcycles, and Tricycles Using Petrol Engines in Southwestern Nigeria

The emissions of carbon monoxide, carbon dioxide, and hydrocarbon from four stroke-powered motorcars and two stroke-powered motorcycles and tricycles in Southwest Nigeria were examined using an automotive 4-gas analyer. Results show that tricycles produced more hydrocarbon and carbon monoxide emissions than motorcycles, while motorcycles emitted more of these pollutants than the gasoline fueled motor cars. (The gasoline fueled motorcars produced lowest hydrocarbon and carbon monoxide while the tricycles produced the highest hydrocarbon and carbon monoxide emissions). On the contrary, motor cars had the highest mean value of carbon dioxide followed by the motorcycles, while tricycles had the least. This could be attributed to the presence of the catalytic converters in some of the motor cars oxidizing carbon monoxide to carbon dioxide. The mean values of hydrocarbon, carbon monoxide and carbon dioxide emissions from motorcars are 630ppm, 10200ppm and 59900ppm. This is much higher than the NESREA (National Environmental standards and Regulations Enforcement Agency) standards as well as Euro II and Euro III (European standards) for vehicular emission. The mean values for hydrocarbon, carbon monoxide and carbon dioxide emissions from motorcycles and tricycles are (2150ppm, 21530ppm and 31200ppm) and (2820ppm, 24880ppm and 38710ppm) respectively. These results do not comply with Nigeria and European emission standards for hydrocarbon, and carbon monoxide. Tricycles and motorcycles account for higher concentrations of hydrocarbon and carbon monoxide pollutants from mobile sources, while they emit carbon dioxide minimally.

Metal contamination and coexistence of metal and antibiotic resistance in Vibrio species recovered from aquaculture ponds with and without history of antibiotic usage in Southwest Nigeria

BackgroundThe use of metal-containing and antimicrobial compounds is a common practice in aquaculture operations in Nigeria. Only a few studies have focused on the impact of these chemicals on metal and antibiotic resistance development in the bacterial flora of aquaculture. This study therefore sets out to fill this gap.ResultsFive metals, namely copper (Cu), zinc (Zn), lead (Pb), nickel (Ni) and chromium (Cr), were detected at different concentrations in the pond water samples, with most values obtained exceeding the maximum recommended national standard for fisheries and recreation water quality criteria set by the National Environmental Standards and Regulations Enforcement Agency (NESREA) in Nigeria. A total of 121 Vibrio spp. were recovered from the aquaculture pond water with Vibrio cholerae having the highest frequency (37) followed by Vibrio parahaemolyticus (36), Vibrio vulnificus (36) and Vibrio alginolyticus (12). Seventy-five isolates were recovered from ponds with history of antibiotic use, while the ponds with no recognized history of antibiotic use had forty-six isolates. The percentage resistance to antibiotics in the isolates was: ampicillin (88.5%), amoxicillin–clavulanate (44.3%), tetracycline (41%), trimethoprim-sulfamethoxazole (22.1%), chloramphenicol (15.6%), ciprofloxacin (11.5%), imipenem (5.7%), ceftazidime (4.1%) and gentamicin (0%). All the isolates tolerated all the metals to 400 µg/mL concentration while only the trio of Pb, Ni and Cr were tolerated beyond the concentration. Zn and Cu appeared to be the most toxic metals on Vibrio spp., with no isolate surviving beyond the 400 µg/mL concentration mark, while 57 of the 121 isolates survived Cr at the highest concentration (3200 µg/mL), making it the most tolerated of the metals.ConclusionThis study reports a high level of metal contamination in the aquaculture ponds studied. The concentration of the metals exceeded the maximum permissible limits in Nigeria. Also, there was coexistence of metal and antibiotic resistance in the bacteria recovered from the aquaculture ponds. There is a need to regulate the use of chemicals, especially antibiotics and some biocidal compounds, to clamp down on the introduction of metals and antibiotics into the aquaculture systems, as these chemicals could facilitate the development of resistance traits in aquaculture bacteria by creating a selective pressure in the aquaculture environment.

Physicochemical and bacteriological assessment of ricemill wastewater discharged into river Benue, Nigeria

Rapid industrialization affects the environment in different ways through indiscriminate disposal of large amount of wastewater into the surrounding water bodies thereby causing serious problems to the environment. This study was conducted to assess the suitability of the ricemill wastewater being discharged into River Benue. Wastewater was sampled from point of discharge (sampling point A) and 20 meters away from the final entry into river Benue (sampling point B). Standardized methods were employed to analyze biochemical oxygen demand (BOD), chemical oxygen demand (COD), total dissolved solids (TDS), total heterotrophic count (THC), nitrate, phosphate, sulphate and pH in the sampled wastewater. Results were generated and compared with permissible standards Results generated from the analyses indicate that in sampling point A, pH ranged from 4.28 to 5.23, TDS ranged from 1478 - 1615 mg/L while THC ranged from1540 - 1600 cfu/ml. In point B, (BOD) ranged from 4.8 - 3.6 mg/L, (COD) ranged from 4.1 - 3.1mg/L, (TDS) 586 - 348mg/L, (THC) 608 - 512 cfu/ml and pH 7.32 - 6.43. Considering these results, (TDS), (THC), nitrate and THC were above permissible limits of World Health Organisation (WHO) and National Environmental standards and regulations Enforcement Agency (NESREA) respectively. Owing to these results, treatment measures and regulatory policies are suggested with a view to checkmating the abuse of river Benue through indiscriminate disposal of wastewater so as to avert imminent dangers it might likely pose to aquatic ecological system.

Evaluating the efficiency of Nostoc commune, Oscillatoria limosa and Chlorella vulgaris in a phycoremediation of heavy metals contaminated industrial wastewater

Industrial wastewater treatment by microalgae is an eco-friendly technology for improving the quality of wastewater. This study evaluated the removal of heavy metals (Cu, Fe, Ni, Pb, Cd and Zn) in wastewater collected from a metal rolling mill industry using Nostoc commune, Oscillatoria limosa and Chlorella vulgaris. Metals were determined using Atomic Absorption Spectroscopy (AAS). Other wastewater parameters determined using the standard procedure were pH, dissolved oxygen (DO), biological oxygen demand (BOD), Cl−, SO42−and NO3-. Data collected were analyzed for descriptive statistics. The results of the raw industrial wastewater were 8.50±0.07 mg/L for Cu, 3.51±0.80 mg/L for Fe, 0.16±0.01 mg/L for Ni, 1.31±0.11 mg/L for Cd and 2.48±1.00 mg/L for Pb. These values were above the permissible standards of the National Environmental Standards and Regulations Enforcement Agency (NESREA) for wastewater. After 45 days of treatment, removal efficiency for heavy metals by the microalgae ranged from 10% (Cu) to 90% (Pb). Despite the appreciable levels of metal removal in wastewater by the microalgae; the treated wastewater still exhibited metal values (except Zn) greater than the permissible limits of the NESREA. The effectiveness of the three microalgae for removing metals followed similar pattern. The present study showed the promising potentials of the three microalgae in wastewater treatment.

Identification of heavy metals source within selected active dumpsites in southeastern Nigeria.

Discriminating contaminant sources is crucial for pollution control. The study aimed at identifying the source(s) of heavy metals in active dumpsite soils from selected areas in Southeastern Nigeria using statistical tools. The dumpsites were Enyimba dumpsite Aba (dumpsite-1), Okpuno-Egbu dumpsite Nnewi (dumpsite-2), Rice mill dumpsite Abakaliki (dumpsite-3) and Nekede dumpsite Owerri (dumpsite-4) in Abia, Anambra, Ebonyi and Imo State respectively. After standard sampling, elemental analysis was carried out using an energy dispersive x-ray fluorescence spectrometer; Chromium (Cr), Manganese (Mn), Cobalt (Co), Iron (Fe), Nickel (Ni), Copper (Cu), Zinc (Zn), Arsenic (As), Lead (Pb) and Cadmium (Cd) were quantified and results showed they were present in high concentrations above control and standard values set by the National Environmental Standards and Regulations Enforcement Agency (NESREA) and the Food and Agriculture Organization of the United Nations (FAO) / World Health Organization (WHO). Metals investigated exhibited variable correlations among themselves suggesting potential multi-element contamination, while soil organic matter (OM) and pH displayed both significant positive and negative influence on the metal availability in the studied soils. Test of significance of the observed correlation were positive and significant (r > 0.9 at p < 0.05/0.01) for Cr/Co, Cr/Fe, Mn/Co, Co/Fe, Cu/Zn, Zn/Pb, Cu/As, Cu/Pb, Zn/As, As/Pb in dumpsite-1; in dumpsite-2, only Ni/Cu; in dumpsite-3, Fe/OM and Cd/OM while in dumpsite-4,Co/Fe, Cu/As, Cu/Pb, Zn/Cd, Ni/OM, and As/Pb. Hierarchical cluster analysis (HCA) and Principal component analysis (PCA) extracted two to three components/groups based on square Euclidean distance and eigenvalues > 1, confirming sources to be from organic pigments in plastics, scrap metals and incinerated biodegradable wastes. This study concludes that statistical methods can provide a scientific basis for monitoring heavy metals accumulation in dumpsite soils.

Ambient Air Measurement of Benzene, Toluene and Xylene Within a Nigerian Petroleum Products Depot and Its Host Environment Using Carbon Adsorption and GC-FID Techniques

Health effects of benzene, toluene and xylene emissions from a Nigerian Petroleum Products depot make stringent adherence to maximum allowable concentration very important. The storage facilities and distribution network and other installations of petroleum products depot are significant sources of benzene, toluene and xylene therefore ambient air of the depot requires observation and assessment. The ambient air concentrations of BTX were been measured within Pipelines and Product Marketing Company, Mosimi Depot and its immediate environment. Air samples were collected on granular activated charcoal through low volume air sampler and extracted with carbon disulphide (CS2) by desorption process.The extracted solutions were subjected to Flame Ionization Detection analysis in a gas chromatograph (Model: HP 6890) using a capillary column HP 5MS with length, inner diameter and particle size set at 30 m × 0.25 mm × 0.25 μm. The gas chromatograph was powered with chemstation RevA09.01 [1206] software to determine the concentrations of each of the identified VOCs species. The concentrations of benzene, toluene, p xylene, m xylene and o xylene ranged between 0.0104 - 0.0711, 0.0019 - 0.0998, 0.0010 - 0.0022, 0.0014 - 0.0026 and 0.0006 0.0019 mg/m3 respectively. The mean values were 0.0277, 0.0389, 0.0013, 0.0019 and 0.00010 mg/m3, respectively. On the average, the observed concentrations did not exceed the tolerance (air concentrations) limits set for Nigeria environment by the National Environmental Standards and Regulations Enforcement Agency (NESREA).

Biotreatment of brewery effluents for aquaculture use using autochthonous fungi

The potential of reducing environmental impact of untreated brewery effluent was investigated. Although concentrations of pollutants in such effluents are usually considered low and inadvertently discharged into adjacent urban drainage facility, mycoremediation to remove dissolved inorganic nutrients in effluent was conducted with a view for aquaculture use in Uyo metropolis, southeast Nigeria. Raw brewery effluents were obtained and screened for indigenous microbial flora. Autochthonous fungi isolated included Aspergillus niger, Verticillium sp. and Mucor sp. The potential use of isolates as alternative treatment of brewery effluents was analyzed for treated and control groups. Treated group was inoculated with pure colonies of fungi isolates while the control group received no fungi treatment or modification. Both groups were incubated for seven (7) days. Thereafter, the physicochemical parameters of raw and remediated effluents were analysed and compared with National Environmental Standards and Regulations Enforcement Agency (NESREA) and aquaculture standards. Results confirmed suitability of autochthonous fungi isolates in mycoremediation of brewery effluent for aquaculture and irrigation.&#x0D; Key words: effluent toxicity, industrial pollution, mycoremediation, aquatic ecosystem, Uyo

Empirical Assessment Of Ammonia And Urea Concentrations In Wastewater From A Pharmaceutical Plant: A Case Study

In several ways, urea is one of the most prominent sources of fixed nitrogen due to its relative abundance in waste water treatment plants. In this study, the wastewater effluent from X-Chemical Industries was considered for hazard analysis in order to ascertain the water quality and impact at the outfall effluent of company X relative to environmental standards. The study period is for December, 2013 – February 2014. Based on the results, it was observed that at the company’s sluice gate, the desorber (primary treatment unit) did not perform optimally. Also, the variation of the parameters measured i.e. urea concentration, pH and ammonia concentrations exceeded the standards established by the World Bank, International Finance Corporation (IFC) and the National Environmental Standards and Regulations Enforcement Agency (NESREA), i.e. against the specified standard of 100 ppm, higher concentrations include December 3, 9, 11, 12, 19, 20, 21, 24, 25, 27, 28 and 29 with corresponding urea concentrations of 1457, 1970.4, 122.7, 163.2, 150.3, 171.4, 148.76, 270.78, 178, 123, 101.33 and 250.43 ppm respectively, whereas that of ammonia is higher than 5 ppm on December 3, 21, 24, 25, 26, 27, 28 and 29 with corresponding concentrations of 8.4, 9.69, 8.13, 9.45, 12.5, 6.98, 22.95 and 9.95 respectively, whereas, it was lowest on other days. It was also observed that the treated waste water advancing the creek (jetty) close to the plant, will have environmental consequences on marine lives such as marine micro-flora as well as fishes.