Automobile Mechanic Workshops Research Articles

Influence of spent oil on soil physical properties and performance of two okra varieties (Abelmoschus esculentus) in PortHarcourt, Rivers State, Nigeria

A study was conducted at the Department of Crop and Soil Science teaching farm, University of Port Harcourt to examine the effect of lubricant automobile oil on soil physical properties and performance of Abelmoschus esculentus for a period of eight weeks. Composite soil samples were collected randomly at depths of 0-20 cm. The soil was placed in 10 kg buckets. Spent lubricant oil collected from the automobile mechanic workshop was used to contaminate the soils at 0, 2, 4, and 6% w/v. Two varieties of Okra V1 (local) and V2 (Clensom spineless) were used. Three okra seeds were planted two weeks after contamination and later thinned to two. Each treatment was replicated thrice; the design was completely randomized. The results showed that the spent oil had no effect on per cent germination on V1 in the treatments and at 0 and 2% contamination for V2. As contamination increases, the percent germination of V2 decreases to 83.3 and 72.2% for 4 and 6% respectively. Increase in spent oil contamination reduced the height of the two varieties. V2 was more affected as percent contamination increases in week 1, thereafter, improves better than V1. No significant (p>0.05) difference in number of plant leaves even as contamination increased except in weeks 3, 5 and 6. Number of leaves decreased with increase in level of contamination and increases as the weeks increased in both varieties. Lowest number of leaves observed at 6% and highest at control in the two varieties. Leaf area of both varieties significantly reduced in contaminated over control though varietyV2 was significantly (p<0.05) higher than V1. Contamination of the soil did not change the textural class of the soil. Significant decrease was recorded in hydraulic conductivity of the soil between the contaminated and control. As the contamination level increased, hydraulic conductivity decreased. Contamination of the soil with lubricant oil increased the soil bulk density. The effect of hydrocarbon contamination was pronounced as there was delay in plant germinations, poor and stunted growth of the two varieties, and yellowing of leaves at the seventh and eighth weeks, especially at 6% contamination on both varieties.

Investigation of Petroleum Hydrocarbons in Soil from Auto-mobile Mechanic Workshops within Ikot Akpaden, Mkpat Enin L.G.A Akwa Ibom State Nigeria

This study investigates the concentrations of total petroleum hydrocarbon (TPH) and total hydrocarbon content (THC) in soil samples from auto-mobile mechanic workshop in Ikot Akpaden, Mkpat Enin. Soil samples were collected in triplicate at different points within the vicinity of auto-mobile mechanic workshop at Ikot Akpaden represented as site A and control samples were obtained within the frontage of Chemistry Department, AKSU represented as site C. Soxhlet extraction and shaking methods were used for the extraction of the total petroleum hydrocarbons and total hydrocarbon content respectively. Each of the sample extracts were purified using column chromatography to remove moisture, polar hydrocarbons, colour interferences and any impurities before GC analysis. Total petroleum hydrocarbons and THC were analyzed using Gas Chromatography (GC-FID) and UV-VISIBLE spectrophotometer respectively. The results obtained from TPH analysis indicates that; 15,223.4 mg/kg was recorded from the auto-mobile mechanic workshop and 808.507 mg/kg was recorded from the control samples. The results from the two stations were higher than the department of petroleum resources (DPR) permissible limit of 50 mg/Kg for soils. There was significant difference in the concentration of total hydrocarbon content, the result obtained showed that, the three sampling point at the mechanic workshop has THC level in the order; A1>A3>A2. The concentration of THC obtained in the three points were greater than the 0.6 mg/Kg limit of total hydrocarbons content allowed by the DPR. The study revealed that the soils were polluted as a result of indiscriminate disposal of waste petroleum products (used engine oil, petrol, diesel and other lubricants) directly on the soil, as well as dumping and burning of waste at the auto-mobile mechanic workshops. Hence, there is need for a holistic and sustainable monitoring and remediation of the environment for a cleaner and healthier environment.

Spatial distribution of polycyclic aromatic hydrocarbons in dust and soils from informal trade sites in southern Nigeria: Implications for risk and source analysis

Polycyclic aromatic hydrocarbons (PAHs) are a group of semi-volatile and persistent organic compounds considered priority pollutants because of their pervasive nature and high toxicity to the ecosystem and humans. Therefore, this study aimed to evaluate the PAH concentrations in dust and soils around informal trade sites (ITS) in Nigeria to determine the level of risk, sources, and significance of these activities to the PAH load of the environment. The 16 US EPA PAHs in dust and soils from ITS were determined by gas chromatography-mass spectrometry (GC-MS). The PAH concentrations in dust from these informal trade sites varied from 120 to 8790, 56 to 4780, and 102–1090 μg kg−1 for automobile mechanic workshops (AMW), car dismantling (CDS), and material recovery sites (MRS), respectively, whereas those of soils ranged from 3000 to 95,500, 554 to 14,700, and 966–25,200 μg kg−1 for AMW, CDS, and MRS respectively. The PAH profiles indicated that 3- to 5-ring PAHs were prominent in dust and soils around the ITS. The concentrations of the US EPA 16 PAHs in dust and soils from these ITS showed no correlation with organic matter, while the concentrations of PAH homologues in soils of these ITS showed no correlation with those of dust. Incremental lifetime cancer risk (ILCR) values in the magnitude of 10−4 to 101 were obtained for adult and childhood exposure to PAHs in dust and soils from these ITS. Exposure to PAHs in dust from these ITS gives rise to less risk than for soils. The results indicated that automobile mechanic workshops contribute more PAHs to the environment than car dismantling and material recovery activities. The source analysis showed that the PAH contamination of these sites arises from burning of biomass, plastic materials, and oils, and emissions from vehicles.

Response of Bacteria Isolated from Spent Engine Oil Contaminated Soil to Hydrocarbons, Metals and Antibiotics

ABSTRACT Automobile Mechanic Workshops (AMWs) in Low- and Middle-Income Countries (LMIC) contribute to the problem of soil contamination with petroleum hydrocarbons and toxic heavy metals as a result of indiscriminate disposal of spent engine oil (SEO). Such contaminated soil ecosystems can serve as reservoirs of bacteria harboring adaptive tolerance to metals and hydrocarbons as well as resistance to antibiotics. This study investigated the growth response of bacteria isolated from spent engine oil contaminated soils collected from AMWs in South-West, Nigeria to different concentrations of petroleum hydrocarbons, heavy metals (Cu, Zn, Pb and their mixture) and clinically relevant antibiotics. Sixty percent of the bacterial isolates (n = 192) from the hydrocarbon contaminated soil samples possess the unique ability to metabolize various hydrocarbons, tolerate heavy metals and resist at least one of the tested antibiotics. The isolates were identified as members of the Genera Pseudomonas, Bacillus, Enterobacter, Burkholderia, Micrococcus, Staphylococcus, Actinomycetes, Citrobacter and Serratia. Significant correlation (p < .05) was observed between hydrocarbon utilization and antibiotic resistance. Results showed SEO contamination plays a role in the development and spread of antibiotic resistance in the soil ecosystem. Thus, it is necessary to enforce stricter regulations on the disposal of SEO and other petroleum hydrocarbons to limit their human and environment associated hazards.

Assessment of Heavy Metals Content in Soil and Groundwater within the Vicinity of Automobile Mechanic Workshops in Yola and Jimeta Towns, Adamawa State, Nigeria

Although heavy metals are naturally occurring elements that are found throughout the earth’s crust, anthropogenic activities such as mechanic workshops are a source of concern for heavy metal contamination. This paper assessed the heavy metals content in soil and groundwater within the vicinity of automobile mechanic workshops in Yola and Jjimeta Towns, Adamawa State, Nigeria using standard methods. Heavy metals were determined using AAS model 210 VGP while pH was determined by electronic JENWAY glass electrode pH meter (Model 3510). Data obtained revealed that, the pH of the sample ranged from 7.52 to 5.19 (provide the average pH levels in the soil and groundwater). From the study conducted, (provide the mean of the heavy metals here) it can be seen that the level of heavy metals found in the soil is in the order of Zn&gt;Ni&gt;Fe&gt;Pb&gt;Cd. While heavy metals found in the ground water of automobile mechanic locations is in the order Ni&gt;Fe&gt;Zn&gt;Cd&gt;Pb. The levels of metals found in the present study were generally below the Department of Petroleum of Petroleum Resources target values for metals in soils.

Assessment of Polycyclic Aromatic Hydrocarbons and Heavy Metal Pollutants in Soil Around Semi Urban Petrol Stations and Automobile Mechanic WorkshopsAssessment of Polycyclic Aromatic Hydrocarbons and Heavy Metal Pollutants in Soil Around Semi Urban Petrol Stations and Automobile Mechanic Workshops

This study assessed the heavy metals and polycyclic aromatic hydrocarbons (PAHs) pollutant in soil around petrol filling stations and automobile mechanic workshops. Samples of soil were acquired from the depth range of 0–15 cm. Toxic heavy metals were analyzed with atomic absorption spectrophotometry. The PAHs were analyzed using phytochemical chromatographic analysis by the Soxhlet extraction method. The soil tested was weakly acidic (6.12–6.81). The trend of the heavy metals’ mean levels in soil followed the order: lead (Pb) > nickel (Ni) > vanadium (V) > cadmium (Cd). The mean levels of PAHs were in the order: 1,2-benzanthracene pyrene > anthracene > fluorene > benzo(b)fluoranthene > 1,1,2-benzopyrelene (BghiP) > naphthalene (Naph) > Dibenz(a, h)anthracene > 1, 2 benzanthracene > benzo(k)fluoranthene > phenanthrene > pyrene > xylene > acenapthylene. Pearson correlation and principal component analysis (PCA) revealed the heavy metals were generated from automobile exhaust and parent rocks. Soil pollution index and Numerov composite pollution index revealed that the soil is safe, clean, and unpolluted with heavy metals. The mean levels of heavy metals were below the European Union (2006) permissible values for uncontaminated soil. The PAH mean values were within permissible standards for unpolluted agricultural, forest, and residential soils. The diagnostic ratios of PAHs, supported by PCA, showed that PAHs in soil were produced by pyrogenic and internal combustion of gasoline and kerosene. This method of soil contamination assessment by heavy metals and PAHs is invaluable for pollution assessors in Nigeria and another area in the world.

Isolation and Optimization of Hydrocarbon – Degrading Bacteria

Aims: To isolate and characterize hydrocarbon – degraders in a contaminated soil sample&#x0D; Study Design: This experiment was carried out under aseptic conditions. The result was confirmed by visible spectrophotometer&#x0D; Place and Duration of Study: Department of Biological Sciences, Microbiology Programme, Clifford University, Ihie Campus, Owerrinta, Abia State, Nigeria, between May 2021 to July 2021&#x0D; Methodology: Soil sample contaminated with hydrocarbon used in this experiment was from an automobile mechanic workshop. A ten-fold serial dilution was made for each soil sample, after which 1 ml of 10-5 dilutions was plated out using pour plate method and incubated at 37 0C for 48 hrs. The isolates were then grown on different hydrocarbons (crude oil, fuel or spent engine oil) and the degradation efficiency was confirmed by visible spectrophotometer.&#x0D; Result: The isolation of hydrocarbon – degrading bacteria in topsoil and subsoil samples of a mechanic workshop located in Isiala Ngwa North Local Government Area Junction, Abia State was carried out. Four bacterial species were isolated from the soil sample collected, the isolates were subjected to hydrocarbon degradation/utilization test of different hydrocarbons (crude oil, fuel or spent engine oil) it was observed that two of the isolates identified as Bacillus and Staphylococcus sp were able to utilize hydrocarbons in the medium more efficiently than other isolates.&#x0D; Conclusion: Hydrocarbon – degrading bacteria were isolated from an auto – mechanic workshop in Isiala Ngwa North, Abia State. Two of the four strains (Bacillus sp and Staphylococcus sp), have the highest potential to use different hydrocarbons (fuel, crude oil and condemn oil) as the sole carbon source. These strains' hydrocarbon – degrading abilities suggest that they could be effective in bioremediation of hydrocarbon – polluted locations. This could be used to combat contamination caused by motor mechanics who carelessly dispose of old motor oil in the environment, as well as general hydrocarbon contamination.

Health risk estimations and geospatial mapping of trace metals in soil samples around automobile mechanic workshops in Benin city, Nigeria

This study was carried out to assess the distribution of trace metals in soil samples from selected automobile mechanic workshops (AMWs) in Benin City, spatially map the concentrations and estimate the health risk indices for the exposed populace. Topsoil samples were collected from twenty-one (21) AMWs in Benin City in 3 composites for three months at each station. Soil samples were analyzed for heavy metals (Pb, Cd, Fe, Cu, Ni, Cr, and Zn) using Atomic Absorption Spectrophotometer. The non-carcinogenic risks caused by exposure to the metals were insignificant, characterized by in mean values of hazard quotient (HQ) and hazard index (HI) below one (1) in adults and children. Carcinogenic risk (CR) occurred only in the children exposed to nickel through ingestion; attributable to ingestion. In adults and children, the risks associated with the uptake routes were in the order of ingestion > dermal contact > inhalation. The hazard index (HI) values of heavy metals for children and adults decreased in the order of Pb > Cr > Cd > Cu > Zn > Ni and were all lower than one (1), which indicated that the children and adults were not at non-carcinogenic risk. The contamination factors (CF) of all metals analyzed were lower than one (1), suggesting low contamination. The average CF decreased in the order of Pb (0.3715) > Zn (0.14) > Cu (0.087) > Cr (0.013) > Ni (0.01) > Fe (0.0007). Potential ecological risks of the trace metals in soils of these workshops revealed low pollution of the soils by the metals. Results indicated that the three routes of uptake in adults and children decreased in the order of ingestion > dermal > inhalation. The non-carcinogenic risks posed by metals to the children and adults were insignificant. Ingested nickel however posed potential carcinogenic risk to only the children. The toxicodynamics of heavy metals in the soil profile demonstrated in this study could be a vital information for future studies and decisions on the management of the health and environment of the study area.

Assessment of Mycoremediation Potential of Fusarium Spp. On Polycyclic Aromatic Hydrocarbon in Western India

Motor or engine oil is a lubricant for engines containing majorly of base oils; these base oils include petrol-based hydrocarbons. Petroleum hydrocarbon contamination is one of the major environmental problems resulting from its large scale uses in transportation, industrial and other sectors. Accidental release and workshop seepage of petroleum products are the key concern of the environment. Fresh engine oil contains polycyclic aromatic hydrocarbons (PAHs). Used engine oil also leads to further generation of PAHs. As an attempt to clean up such hydrocarbons, bioremediation or biodegradation methods are adapted. Bioremediation is a cost effective and eco-friendly treatment for oil contaminated materials by the use of micro-organisms. The present study is an attempt to isolate and find out hydrocarbon degrading fungi from oil and petroleum contaminated regions. Biodegradation potential of soil mycobiota isolated from automobile mechanic workshop in Virar on engine oil was investigated using standard methods. The most capable oil degrading fungi was identified morphologically by wet mount technique as Fusarium sp. The biodegradation of hydrocarbons and oil was determined by using 2,6 Dichlorophenol-indophenol (DCPIP) assay and gravimetric analysis. The quantitative estimation of engine oil degradation showed rate of degradation as 87% and 89%. This study confirms that isolated Fusarium sp. has the potential exploited in the bio-treatment and removal of hydrocarbons from the polluted soil. Results were recorded in the form of biodegradation percentage of hydrocarbon. The present study and their results can give unique future prospects in the field of bioremediation and biodegradation of petroleum contaminated soil.

Bioremediation of Spent Engine Oil Contaminated Soils Using Indigenous Fungi Species

Spent engine oil is derived from lubricating oil which has been used to lubricate various internal combustion engines and it is drained out for disposal during servicing of the engine. Spent engine oil causes great damage to soil and soil microflora when disposed indiscriminately. Thus, the bioremediation of spent engine oil contaminated soil was studied using indigenous degrading fungi isolated from hydrocarbon contaminated soils obtained from automobile mechanic workshops located at both Okpe and Uvwie Local Government Areas of Delta State, in the Niger Delta region of Nigeria. Three (3) fungi isolates with high engine oil biodegradability potential were used for the spent engine oil (SEO) bioremediation study. The fungi isolates used for the test were identified as, &lt;em&gt;Aspergillus glaucus&lt;/em&gt;, &lt;em&gt;Trichoderma polysporum&lt;/em&gt; and &lt;em&gt;Talaromyces flavus&lt;/em&gt;using the API 20C method. The test microcosms were incubated for four weeks at 28 ± 2&lt;sup&gt;o&lt;/sup&gt;C. Physicochemical parameters such as, Sulphate concentrations, Total petroleum hydrocarbon, Nitrate concentrations, Phosphate concentrations, Total organic carbon content, pH and Hydrocarbon utilizing fungi counts were monitored weekly using standard ASTM methods to assess the biodegradation of the spent engine oil. At the end of the test duration, &lt;em&gt;Talaromyces flavus &lt;/em&gt;recorded the highest percentage spent engine oil biodegradation (69.66%) for the 5% SEO experimental set up. Similarly, &lt;em&gt;Aspergillus glaucus &lt;/em&gt;recorded the highest percentage SEO biodegradation (66.16%) for the 10% experimental set up. Thus, &lt;em&gt;Talaromyces flavus &lt;/em&gt;and &lt;em&gt;Aspergillus glaucus &lt;/em&gt;could be used to effectively bioaugment the bioremediation process of spent engine oil contaminated soils to restore the soil to its original state within a short period of time.

Impact of Informal Auto-Mobile Mechanic Workshops Activities on Groundwater Quality in Ibadan, Nigeria

The detrimental effect of the activities in informal auto-mobile mechanic workshops is a major public health concern; and its impact on groundwater contamination cannot be ignored. We assessed the effect of activities of mechanics in auto-mobile workshops on the quality of groundwater sources. Water samples were collected from hand dug wells situated within 0 to 50 metres in twenty auto-mobile workshops randomly selected across three zones. A residential area was selected as the control site. Analysis of water for some physico-chemical parameters (pH, TDS, Electrical Conductivity, Alkalinity, Oil and Grease) and the heavy metals (Cu, Cd, Cr, and Pb) was done using standard methods. Sanitary inspection was also carried out at each well location. Results were compared with the control and regulatory standards Nigerian Industrial Standard for Drinking Water Quality (NISDQW) and World Health Organization (WHO) guidelines for drinking water quality. Results revealed that mean values of pH, TDS and Electrical conductivity for the three zones, Alphonso, Temidire, and Ojoo were within WHO limits. The concentrations of Cu, Cd Cr and Pb in the water samples ranged from 0.02 - 6.12 mg/l, 0.1 - 2.19 mg/l, 0.2 - 0.79 mg/l and 0.02 - 35.8 mg/l across the three zones respectively. Mean concentrations of Cu (mg/l) were significantly higher in Alphonso (2.5 ± 2.06) than in other zones. Mean concentration of Cr (mg/l) was 0.34 ± 0.28, 0.37 ± 0.13 and 0.31 ± 0.3 for Alphonso, Temidire and Ojoo respectively. Cadmium was also present in all the zones but Pb was only detected in Alphonso. The mean concentrations for heavy metals were significantly higher when compared with the permissible limits for both NISDQW and WHO. The degree of groundwater contamination indicates poor water quality in the study area, and this requires regular monitoring. Enforcement of environmental regulations guiding activities of auto-mechanics should be done so that they can embrace environmentally friendly practices to reduce pollution.

Impact of Informal Auto-Mobile Mechanic Workshops Activities on Groundwater Quality in Ibadan, Nigeria

The detrimental effect of the activities in informal auto-mobile mechanic workshops is a major public health concern; and its impact on groundwater contamination cannot be ignored. We assessed the effect of activities of mechanics in auto-mobile workshops on the quality of groundwater sources. Water samples were collected from hand dug wells situated within 0 to 50 metres in twenty auto-mobile workshops randomly selected across three zones. A residential area was selected as the control site. Analysis of water for some physico-chemical parameters (pH, TDS, Electrical Conductivity, Alkalinity, Oil and Grease) and the heavy metals (Cu, Cd, Cr, and Pb) was done using standard methods. Sanitary inspection was also carried out at each well location. Results were compared with the control and regulatory standards Nigerian Industrial Standard for Drinking Water Quality (NISDQW) and World Health Organization (WHO) guidelines for drinking water quality. Results revealed that mean values of pH, TDS and Electrical conductivity for the three zones, Alphonso, Temidire, and Ojoo were within WHO limits. The concentrations of Cu, Cd Cr and Pb in the water samples ranged from 0.02 - 6.12 mg/l, 0.1 - 2.19 mg/l, 0.2 - 0.79 mg/l and 0.02 - 35.8 mg/l across the three zones respectively. Mean concentrations of Cu (mg/l) were significantly higher in Alphonso (2.5 ± 2.06) than in other zones. Mean concentration of Cr (mg/l) was 0.34 ± 0.28, 0.37 ± 0.13 and 0.31 ± 0.3 for Alphonso, Temidire and Ojoo respectively. Cadmium was also present in all the zones but Pb was only detected in Alphonso. The mean concentrations for heavy metals were significantly higher when compared with the permissible limits for both NISDQW and WHO. The degree of groundwater contamination indicates poor water quality in the study area, and this requires regular monitoring. Enforcement of environmental regulations guiding activities of auto-mechanics should be done so that they can embrace environmentally friendly practices to reduce pollution.

Physico-Chemical Properties of Soil Sourced from Automobile Mechanic Workshop in Ikoku Mechanic Village, Mile 3 Diobu, Port Harcourt, Rivers State, Nigeria

This study investigated the impacts of automobile mechanic workshops on the concentrations of PAHs, T.H.C, T.O.C, pH, EC, Cations, heavy metal and particle size distribution in urban soil sourced from automobile workshops in Ikoku mechanic village, Mile 3 Diobu, Port Harcourt, Rivers state. Six samples were collected at sites of close proximity to the selected automobile workshops (Experimental sites) and sites that are far away from the workshop without the influence of automobile mechanic activities (control sites). The levels of Zinc (Zn), lead (Pb), Chromium (Cr) and cadmium (Cd) were determined using atomic absorption spectrophotometer (AAS), the PAHs were determined using GC-FID and GC-MS. The levels of T.O.C and T.H.C were determined using Titration method and Genesis 10 UV spectrometer, the pH and EC were determined using Pre-calibrated pH and EC meters, the Particle Size Distribution was determined by Sieve analysis method. Data interpretation involved the use of descriptive statistics for test of significant variation in the levels of heavy metals, Physico-chemicals and PAHs between the experimental sites and control site. Findings revealed that concentrations of Heavy metals, PAHs, T.H.C, T.O.C, EC and Cations were generally higher in soils under the influence of automobile mechanic workshop activities than sites with no such influence. The mean values of Pb, Zn, Cr and Cd were 32.94, 74.17, 5.35 and 2.86mg/kg respectively in soils under the influence of automobile mechanic activities and 32.52, 100.69, 10.09 and 3.68mg/kg respectively in soils with no such influence. The mean concentrations of PAHs, T.H.C, T.O.C, EC, pH and Cations as compared to those of the Control sites are 332.35 to 65.28, 2.47 to 1.94, 36.20 to 22.35, 273.2 to 119.7, 7.145 to 7.245 and 30.52 to 42.99 respectively. There were significant variations in the levels of PAHs, Heavy metals and the Physico- chemical parameters between the experimental sites and the control sites. The Particle Size Distribution revealed that the soil is of low permeability thus limiting the degree of seepage and supporting more accumulation of the contaminants at the top soil. It is recommended that mechanic villages should be sited far from residential areas, Quick remediation of polluted soil using various remediation methods should be encouraged and continuous education and training should be provided for the automobile workers, emphasizing on the environmental implications of their poor occupational waste management.

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Evaluating genotoxic effects of plants exposed to heavy metals and polycyclic aromatic hydrocarbons at dumpsite, mechanic workshop and metal scrap site in Lagos

Soil contamination from heavy metals and polycyclic aromatic hydrocarbons (PAHs) from dumpsite, automobile mechanic workshop and metal scrap sites pose human and ecological health risks. This study assesses the levels of heavy metals and PAHs in soils from these sites and their effects on the DNA yield and fragmentation of native plants around there. The DNA yield and fragmentation were compared to those obtained from non-polluted sites (control). DNA of the plants species, Musa acuminata (banana), Jatropha curcas (Barbados nut), Carica papaya (pawpaw), Axonopus compressus (carpet grass), Sida acuta (wireweed), and Eleucine indica (crabgrass grass) for polluted sites and control were analyzed using Gel electrophoresis. Soil heavy metals; copper (Cu), zinc (Zn), lead (Pb) and chromium (Cr) were evaluated from dumpsite, metal area and mechanic workshop using inductively coupled plasma-atomic emission spectrometry (ICP-AES). Polycyclic aromatic hydrocarbons were also determined from soils of the polluted sites using the GC/MS spectrophotometry. The result obtained from the DNA analysis showed that DNA yield and fragmentation of the polluted plants had higher indices than the controls which shows that heavy metals and polycyclic aromatic hydrocarbons affect the DNA of the plants. The effects of the pollutants on DNA of polluted plants had more smearing in their tissue than non-polluted plants. Heavy metals evaluation showed that zinc level was the highest in all the study sites; dumpsite, metal area and mechanic workshop (5.146 mg/kg, 2.709 mg/kg and 1.990 mg/kg respectively) than the control (p<0.05). Chromium was the least present (0.022 mg/kg, 0.018 mg/kg and 0.002 mg/kg respectively). The results of this study indicate that dumpsite, mechanic workshop and metal scrap sites are potential sources of PAH and toxic metal, which can pose serious human health and ecological risks. Keywords: DNA fragmentation, heavy metals, Gel electrophoresis, polycyclic aromatic hydrocarbon

Phyto-extraction ability of &lt;i&gt;Digitaria exilis&lt;/i&gt; (Fonio) to heavy metals

Among the different contaminants in the environment, heavy metals are unique due to the fact that they cannot be broken down to non-toxic forms. The research was conducted to determine the remediation potential of Digitaria exilis and to identify the varieties that can tolerate heavy metals contamination. Soil was collected in an Automobile mechanic workshop, Government Reserved Area (GRA) Ado-Ekiti. Five kilograms (5 kg) of soils collected was air dried, sieved and filled into plastic buckets. The experiment was a completely randomized designed with three replicates. Three different accessions of Digitaria exilis namely; Jakah D Iburua (JAK), Dinat D Iburua (DID) and Jiw D Iburau (JIW) were planted. Soils were watered till field moisture capacity. Plant height was determined every two weeks after planting. Soil analysis was carried out to determine the physical and chemical properties before and after the experiment. Heavy metals including Cd, Fe, Zn, Pb, As and Cu were determined in the plant roots and shoots using Atomic Absorption Spectrophotometer (AAS). Accession JAK Bio-accumulated heavy-metals in their root than shoot, consequently, significant high plant height was recorded. However, shoot of accession JAK accumulated 22 % Pb, 46.78% Cu and 37.5% Cd and 20.3% Zn than others whereas accession DID accumulated As than accession JAK. Therefore, accession JAK demonstrated highest phyto-extraction of heavy-metals potentials at the root. Variety JIW has the lowest plant height, root and shoots heavy metals accumulation. Although heavy metals contaminated soil affected the growth of D. exilis, nevertheless accession JAK has the highest productivity under this condition and can be further recommended in phyto-extraction of heavy-metals in polluted sites.Keywords: Phyto-extraction, Digitaria exilis and Heavy-metals

Assessment of Heavy Metals Pollution in Sediments from Ologe Lagoon, Agbara, Lagos, Nigeria

This study was carried out to assess the level of heavy metals pollution in Ologe Lagoon, Agbara, Lagos, Nigeria. The Lagoon receives effluents from industries in the Agbara Industrial Estate. Cored Soft sediments were retrieved from six random sampling points within the Lagoon and labeled (S1, S2, S3, S4, S5 and S6). Subsamples of the sediments were prepared and analyzed for heavy metal concentration. The result from the heavy metal analysis of the sediments shows that average concentration of Mn, Zn, Cr, Ni, Cr, Ni, Co, Cu and Pb in the samples was 278.1 ppm, 21.7 ppm, 14.2 ppm, 6.6 ppm, 6.4 ppm, 6.4 ppm and 4.4 ppm, respectively. The correlation between the heavy metals varies from 0.71 to 0.98 shows that they have a strongly positive degree of association which suggests that they are from the same source. The geo-accumulation values for Cu in all stations ranged between (1 - 2.8 ppm) and it can be deduced that the sediments are moderately to strongly polluted. Pb varies between 1 and 2.1 suggesting that the sediments are moderately polluted. Zn exhibits strong pollution levels with a range from 2.5 and 3.5 ppm. Co is moderately polluted with 1.5 - 2.4 while Mn shows the highest level of pollution in all stations with Igeo values ranging between 4.1 and 5.8. This study showed that the Lagoon accumulates heavy metals as a result of anthropogenic activities evident in the dumping of municipal, sewage, industrial waste in the environment and domestic activities such as auto mobile transportation and mechanic repair workshop. Based on sediment quality guidelines, the Ologe Lagoon level of pollution ranged from Cu > Pb > Zn > Ni > Co > Mn > Cr > Al with Mn having the highest level of pollution.

Monitoring the level of heavy metals pollution in automobile mechanic workshops using tree barks

The level of heavy metals at automobile mechanic workshops were monitored by examining tree barks of different species and influence of sampling heights on the metals level. This was with the aim of determining the suitability of using tree barks in monitoring the level of air pollution. Tree bark samples were collected at 2 and 4m heights from different automobile mechanic workshops around Ile-Ife metropolis and at control sites. The samples were transported to the laboratory, oven-dried at 60 ˚C to a constant weight; ground and analyzed for Pb, Cu, Cd, Fe and Zn using Atomic Absorption Spectrophotometer. Results showed that the concentration of Fe, Cu and Pb at the mechanic sites were significantly (p 0.05) between the sites. The correlation value of 0.94 was observed between Zn and Cd; 0.76 between Pb and Cd, and 0.50 between Zn and Pb. This study showed that different species have different affinities for air pollutants and that soil particles also acted as a source of heavy metals in our environment. Keywords: Atmospheric, Automobile, Pollutants, Soil particle, Trace metals, Tree barks

Pollution Status of Heavy Metals in Spent Oil-Contaminated Soil in Gwagwalada

The pollution status of some selected heavy metals namely: Pb, Fe, Zn, Cu, Cr, Ni and Cd, in spent oil-contaminated soil were investigated. The soil samples were obtained from different spots of the automobile mechanic workshop, wet digested and the concentrations of the heavy metals in the soil digest determined using Atomic Absorption Spectrophotometer (AAS). The concentration of Pb was significantly higher (p&lt;0.05) than the concentrations of each of the other six heavy metals while cadmium had the least concentration. In most of the sampling spots analyzed, the concentrations Cd were below the detection limit of the instrument used. The order of the concentrations of the heavy metals were Pb&gt; Fe&gt; Zn&gt; Cu&gt; Cr&gt; Ni&gt; Cd and Fe &gt; Cr &gt; Zn&gt; Pb&gt; Cu&gt; Ni&gt; Cd for the spent oil-contaminated and control soils respectively. The concentration of iron, cadmium, copper, nickel and zinc in the control soil were significantly lower (p&lt;0.05) than the concentration of iron, zinc and lead in the oil-contaminated soil. The concentration of Pb exceeded the limits of both the background and intervention lead value set by DPR (Department of Petroleum Resources) of Nigeria. The contamination and potential ecological factors of Zn, Cu, Fe, Cr and Cd were categorized low except Pb which was categorized as having very high contamination factor and moderate potential ecological risk factor. The entire studied spots showed moderate degree of contamination. The potential risk index of the heavy metals ranged from 44.23 to 51.91, which had a low grade category; implying that the heavy metals have caused low harm to the soil of the workshop. This paper gives information on the present status of heavy metals in the soil and the need for continuous monitoring so as to avert further contamination of this workshop.

Assessment of Heavy Metal Pollution in Soil from an Automobile Mechanic Workshop in Abuja

Assessment of Heavy Metal Pollution in Soil from an Automobile Mechanic Workshop in Abuja