Acid-activated corn silk as a promising phytosorbent for uptake of Malachite green and Cd (II) ion from simulated wastewater: equilibrium, kinetic and thermodynamic studies.

Malachite green (MG) dye and cadmium metal ion are toxic pollutants that should be removed from aqueous environment. The recent study aimed to examine the adsorption behavior of MG dye and Cd (II) from wastewater onto low-cost adsorbent prepared by activating corn silk with nitric acid (ACS) and characterized by SEM, FTIR, XRD, BET and TGA. The optimum MG and Cd (II) adsorption was observed at pH 7 and pH 9 and maximum uptake of both pollutants was at 0.5 g dosage, 60 mins contact time and 20 mg/L initial concentration. The retention of dye and metal ion by the studied adsorbent was best fit to Langmuir isotherm and Pseudo-second order kinetics. The maximum monolayer coverage capacity of ACS for MG dye and Cd (II) ion was 18.38 mg/g and 25.53 mg/g, respectively. Thermodynamic studies predicted a spontaneous reaction with exothermic process for MG dye whereas an endothermic and spontaneous process was confirmed for Cd ion based on estimated parameters. The adsorption mechanism of MG dye and Cd (II) uptake was by combination of electrostatic interaction, pore diffusion, ion exchange, pie-pie attraction, hydrogen bonding, and complexation. The adsorbed pollutants were effectively desorbed with significant regeneration efficiency after successive five cycles that proved the potential of low-cost biosorbent for selective sequestration of cationic dye and divalent metal ion from effluents.

The use of nitric acid-modified corn silk has been reported to enhance its adsorption performance over the unmodified cob for pollutants such as cadmium ions and malachite green. Although there may be no recorded data on the adsorption efficiency of acid-treated corn silk for selected pollutants, it can be considered as a prospective bio-sorbent owing to its chemical composition and functional groups for exchange of hydrogen ions for other cations.

Ecological pollution features and health risk exposure to heavy metals via street dust and topsoil from Nkpor and Onitsha in Anambra, Nigeria.

The manuscript presents the investigation results on the pollution and risk of metal mines, and it is considered an important report on environmental pollution near mines in Nigeria, with archival value. The research involved soil sampling and heavy metal analysis for about 12 months in three metal mines. Based on these results, the paper provides information on pollution levels and hazards using well-known methods like pollution and ecological risk indexes. The increasing population in urban communities attracted by various industrial, economic and social activities causes contamination of atmospheric environment that can affect human health. We investigated heavy metal distributions, correlation coefficient among elements, ecological indices and probable health risk assessment in street dust and topsoil from Nkpor and Onitsha urban suburb, Nigeria. The mean concentration of heavy metals in car dust from Onitsha and Nkpor suburb follows thus: Fe > Mn > Cu > As > Pb > Ni > Cr. The decreasing trend of heavy metal in rooftop dust from both area: Fe > Mn > Cu > Pb > As > Ni > Cr whereas metal contents in topsoil were: Fe > Mn > Cu > Pb > Ni > Cr > As for both areas. The degree of pollution indices was characterized by contamination factor (CF), geo-accumulation factor (I-geo), pollution load index (PLI), Nemerow (PN), ecological and potential ecological risk index (ER and PERI) which indicated low pollution in the urban street environment. The results of Principal Component Analysis (PCA) and Hierarchical Cluster Analysis (HCA) showed that the estimated heavy metals displayed sources from atmospheric deposition, natural origin and anthropogenic sources. Risk assessment revealed that ingestion of dust and soil was the significant route for heavy metals exposure to the populace followed by inhalation, then dermal contact. Considering all factors, non-cancer risk was more prominent in children than adults and no significant health hazard could be attributed to both aged groups as of the period of study except for As and Ni that needs constant monitoring to avoid exceeding organ damaging threshold limit of 1 × 10-4.

Ecological pollution and health risk monitoring assessment of polycyclic aromatic hydrocarbons and heavy metals in surface water, southeastern Nigeria.

Polycyclic aromatic hydrocarbons (PAHs) and heavy metals (HMs) are predominant pollutants linked with anthropogenic activities across a host of environmental mediums. The level of pollution, ecological and health risk were assessed in surface water from Ekulu in Enugu metropolis, Nigeria for 17 PAHs and selected HMs (As, Cd, Cr, Cu, Pb, Ni, Zn) components. PAHs and HMs were determined using a gas chromatography-flame ionization detector (GC-FID) and atomic adsorption spectrophotometer (AAS). The total PAHs in station A (3.17mg/l), B (1.51mg/l), and C (1.83mg/l) were due to high molecular weight (HMW) PAHs than low molecular weight (HMW) PAHs. HMs contents were within USEPA and WHO minimum contamination levels (MCL) except Cr and Pb. The molecular diagnostics of PAHs showed that incomplete combustion of carbonaceous compounds was dominant, while petrogenic was insignificant across all samples. The ecological indices of PAHs and HMs varied from medium to high pollution due to anthropogenic activities that pose a threat to the ecosystem. The non-carcinogenic models showed that hazard index (HI) ranged from PAHs (0.027 - 0.083) and HMs (0.0067 - 0.087) which is less than unity implying no adverse health issues. The lifetime cancer risk (LCR) for PAHs (4.21×10-4 - 9.61×10-4) and HMs (1.72×10-5 - 3.98×10-5) suggested significant cancer risk is possible over some time for a population of 1 in 10,000 and 100,000 for both PAHs and HMs exposure for 70 years. Therefore, there is an urgent need for proper pollution control and mitigation plan to preserve both age groups from being continuously exposed to anthropogenic activities in the Ekulu River and further study should be carried out to monitor the available toxicants.

Chemometric and risk assessment of nitrogen composition of atmospheric rainwater from diverse surfaces in Rivers State, Nigeria.

Organic and inorganic nitrogen ions in the environment play important role across environmental matrices. Rainwater samples collected from ambient and different roofing surfaces (zinc, aluminium, asbestos and stone-coated roofing sheets) from selected locations at Ogale, Rumuodomaya/Rumuodome, Diobu and Chokocho within Rivers State, Niger Delta, Nigeria, from April to June, July to August and September to October depicting three regiments of early, mid and late rains. The samples were analysed for Kjeldahl nitrogen, ammonium, nitrate and nitrite using APHA methodology. Quantitative assessment showed that Kjeldahl nitrogen were in range of 0.11 to 28.05 mg/L; ammonium 0.50 to 20.22 mg/L, nitrate from 0.12 to 22.69 mg/L and nitrite from 0.15 to 3.90 mg/L. Parameters decreased from early to late rain, which can be attributed to rain dilution factor potential, wind pattern and emission from anthropogenic sources that influenced the rainwater quality across surfaces. Nitrogen results showed that dry and wet deposition has great impact; atmospheric aerosols and biogeochemical interactions can affect water quality. Monthly variation showed that Ogale had high regression compared to other locations due to close proximity to oil and gas emission and marine contribution. Neutralization factor showed that nitrate-nitrite compounds have strong correlation with ammonium ion. Non-carcinogenic risk assessment using US EPA model showed hazard index less than one (1), thus no associated health effect of nitrate and nitrite in rainwater. In conclusion, it is evident that nitrate/nitrite levels and other nitrogen derivatives in rainwater in crude oil-producing Niger Delta and its continuous consumption can cause negative health outcome.

Chemometrics, health risk assessment and probable sources of soluble total petroleum hydrocarbons in atmospheric rainwater, Rivers State, Nigeria.

Total petroleum hydrocarbons (TPHs)-(aliphatic and aromatic) were analysed for in atmospheric rainwater between April-June; July-August; September-October depicting early, mid, late rain of 2019. Sampling at Rumuodomaya/Rumuodome and Ogale in Rivers State using basins fastened to a Table 2M above ground and 120 M from high features, Rainwater was analysed after treatment using Agilent GC-FID. Results show cumulative TPHs at R/R were 56.6551 mg/L, 39.5201 mg/L and 7.2283 mg/L, Ogale: 9.1217 mg/L, 59.4923 mg/L and 21.9825 mg/L. Aliphatic hydrocarbons: C5-C8 were < 1, low contamination, other carbon aggregates (C9-C16, C17-C35, and C36-C40) indicate high contamination. Chemometric assessment showed high contamination. TPHs aggregates at Rumuodomaya/Rumuodome were-C8-C11 (1.034 and 1.005) early rain, C18-C25 and C26-C33 has Carbon preference index of 1.287 and 1.630 (mid-rain), C26-C33 has CPI of 1.288 (late-rain), Ogale area, C26-C33 has CPI of 1.732 (early-rain), mid-rain C8-C11 (2.768) and C12-C17 (5.368). Pristane/phytane ratio indicated biogenic and pyrogenic sources. Average carbon length of TPHs for odd n-alkanes were C9-C11 (9.446) and C35-C39 (38.980), C9-C11(10.238), C35-C39 (36.510); C9-C11 (10.240) and C35-C39 (36.934). Average daily intake depicted possible health issues for children and adults as hazard index > 1 for aromatics.

Hazards and risk assessment of heavy metals from consumption of locally manufactured painkiller drugs in Nigeria.

In the informal sector of Nigeria's economy, jobs are done manually as against automation resulting in body stress and pain, hence the need for painkiller drugs. Thirty different locally manufactured painkiller drugs, with analgesic, antipyretic and anti-inflammatory effects, were randomly sampled from pharmaceutical shops within Awka in October 2016. The drugs were pulverised, sieved and ashed before digestion using conc aqua regia HCl : HNO3 (3:1), carcinogenic heavy metals (arsenic, cadmium, chromium, mercury, nicked and lead) were assayed using Varian AA240 atomic absorption spectrophotometer (AAS). Risk assessment was carried out using US EPA model. The highest levels of arsenic (0.350 mg/kg) were found in samples with code 01, 03 and 020, cadmium (0.107 mg/kg and 0.144 mg/kg) were in samples code 013 and 028, and samples 03 and 011 had chromium levels as 6.637 mg/kg and 5.298 mg/kg. Highest value of mercury (0.470 mg/kg) was in sample code 01. All the painkiller drugs have nickel in the range of 0.046-0.448 mg/kg while highest values of lead were in sample code 05, 025 and 029 as 2.47 mg/kg, 1.11 mg/kg and 1.16 mg/kg. Non-cancer risk ranged as As (Nd -1.60 × 10-3), Cd (Nd-1.97 × 10-4), Cr (Nd-6.06 × 10-6), Hg (Nd-2.15 × 10-4), Ni (9.93 × 10-6-3.34 × 10-5) and Pb (Nd-4.36 × 10-4) while the cancer risk were As (Nd-1.63 × 10-7), Cd (Nd-4.45 × 10-9), Cr (Nd-1.56 × 10-7), Hg (Nd -1.53 × 10-9), Ni (1.50 × 10-10 -1.46 × 10-9) and Pb (Nd-8.82 × 10-9). The total cancer risk (TCR) and total non-cancer risk (TNCR) for all the heavy metals were in the range of 7.21 × 10-13-1.25 × 10-10 and 1.51 × 10-7-5.56 × 10-5 respectively. The TCR was below 1 × 10-6 -1 × 10-4 range while TNCR for heavy metals was below 1; the values established by US EPA. In conclusion, continuous consumption of locally Nigerian made painkiller drugs may expose the subjects to heavy metal toxicity.

Health risk assessment of cadmium, chromium and nickel from car paint dust from used automobiles at auto-panel workshops in Nigeria.

Nigeria's economic problems which inhibited local production has resulted in massive importation of used automobiles. Most of these automobiles need some repairs and reworking, having outlived their lifespan in the manufacturer's country. This study centers on the human carcinogenic and non-carcinogenic health risk assessment of cadmium, chromium and nickel exposures from reworking of imported used vehicles. Scraped car paint dusts from 56 Japanese made cars were collected from 8 different panel beating (body works) workshops (A-H) in Southeastern Nigeria. They were homogenized, mixed, divided into fine particles, filtered and digested by standard method. The filtrates were assayed for cadmium, chromium and nickel with atomic absorption spectrophotometry (AAS, 200A), workshops F and D have the highest concentration (mg/kg) of Cd (3.58 ± 0.02) and (3.36 ± 0.04) and higher than levels in workshops A, B, C, E, G and H. Chromium (mg/kg) in workshops F and G were (2.87 ± 0.04) and (2.95 ± 0.06) and higher than the other workshops. Nickel in workshop A (3.84 ± 0.04) is close to other workshop values. The highest hazard quotients for adults were cadmium in workshops B (1.37E-01), D (1.69E-01), E (1.79E-01) (inhalation), chromium [workshops G (5.45E-02), F (5.29E-02) and C (5.24E-02) inhalation]. Nickel -workshop A (5.9E-03) for children (inhalation). HQ in children through ingestion is cadmium (3.72E-04) workshop F and ingestion- 3.21E-01(workshop F) while nickel is 1.06E-02 (workshop A).The highest cancer risks were in exponents -4,-7 and -8 (adult) and -3, -6 and -9 (children) for workshops A-H through inhalation, ingestion and dermal contact, exposures to scrap car paint dust may be of significant public health importance in Nigeria as it can add to body burden of some carcinogenic heavy metals.

Human health risk assessment of lead, manganese and copper from scrapped car paint dust from automobile workshops in Nigeria.

The economic downturn in Nigeria and Structural Adjustment Programme led to the flooding of Nigerian market with imported used automobiles. Most of these vehicles needed refurbishing and reworking. The present study is a human health risk assessment of metal exposure resulting from reworking of imported used vehicles in Nigeria. Scrap paint dusts from 56 Japanese made cars were collected from 8 different mechanic villages (workshops A-H] in Southeastern Nigeria. Scrap paints were homogenized, mixed, divided into fine particles and digested by standard method. The filtrates were assayed of lead, manganese and copper with atomic absorption spectrophotometry (AAS). Workshop B has the highest concentration of Pb (4.26 ± 0.93). Manganese in workshops A and F were (3.31 ± 0.85) and (3.04 ± 0.47) respectively and were higher than the levels from workshops C, B, D, G and H. Copper in workshop D (7.11 ± 0.21) was significantly greater than the other workshops. The highest hazard quotient (HQ) through ingestion, inhalation and dermal exposures in adults were 9.44E-05 (workshop B), 4.20E-01 (workshop B) and 1.08E-05 (workshop D) respectively. The highest values for HQ through ingestion, inhalation and dermal in children were 8.82E-04, 7.61E-01 and 2.86E-05 all in workshop B respectively. For children, the highest carcinogenic risk levels were 7.05E-08, 6.09E-05 and 2.29E-10 for ingestion, inhalation and dermal exposures respectively. In adults, the carcinogenic risk levels were 7.55E-09, 3.39E-05 and 8.67E-10 for ingestion, inhalation and dermal exposures respectively. Chronic exposure to scrap car paint dusts may be of significant public health importance in Nigeria as this may add to the body burden of some heavy metals.

Heavy metals health risk assessment for population via consumption of food crops and fruits in Owerri, South Eastern, Nigeria.

BACKGROUND: This study assessed lead, cadmium, and nickel level in food crops, fruits and soil samples from Ohaji and Umuagwo and Owerri in South Eastern Nigeria and estimated the potential health risks of metals. Samples were washed, oven-dried at 70-80°C for 24 h and powdered. Samples were digested with perchloric acid and nitric acid. Metals were analysed with Unicam Atomic Absorption Spectrophotometer. RESULT: The concentration of Pb, Cd, and Ni in Ohaji exceeded the maximum allowable concentrations for agricultural soil as recommended by EU. Lead, Cd, and Ni in the food crops were highest in Oryza sativa, Glycine max, and Pentabacta microfila respectively. Highest levels of Pb, Cd, and Ni, in fruits were detected in Canarium schweinfurthii, Citrus reticulata, Ananas comosus respectively. The true lead and cadmium intake for the rice based meal were 3.53 and 0.034 g/kg respectively. Whereas the true intake of lead and cadmium for the cassava based meal were 19.42 and 0.049 g/kg respectively. CONCLUSION: Local food stuff commonly available in South Eastern Nigeria villages may contribute to the body burden of heavy metal. This is of public health importance.

Water-quality issues in the Niger Delta of Nigeria: a look at heavy metal levels and some physicochemical properties.

INTRODUCTION: Water contamination is a notable environmental problem of the Niger Delta, Nigeria. The present work is an improved attempt at a scientific discourse of water-quality issues in the Niger Delta of Nigeria with respect to heavy metal levels in surface water in view of the hitherto dearth of scientific data. MATERIALS AND METHODS: We have looked at the Fe, Mn, Cu, Cd, Cr, Pb, Ni, Zn (quantified by atomic absorption spectrophotometry) profiles and some physicochemical properties (pH and salinity) of some surface water used by the local population in the mid Niger Delta. Surface water samples were collected from these surface waters in the dry and rainy seasons. RESULTS: Akiplai wellhead stream and Etebde River had the highest level of iron. In Delta State, high levels of cadmium were found in Ijala creek, Ubeji creek, Jeddo River, and Ekpan River, respectively. High lead levels were seen in Jeddo River, Ekurede-Itsekiri Creek, and Ughelli River. In River State, Tombia River had the highest levels of chromium, lead, and nickel. Ijala creek, Eja-Etan, Ifie-Kporo, Ubeji Creek, Jeddo, Ekpan Rivers, and Ekurede-Itsekiri Creek, all in Delta State, presented highest salinity levels. Orash River, Ughewhe stream, and Egbo stream have a lowest pH of 5.22, 5.32, and 5.53, respectively, while Ifie-Kporo River have a highest pH of 8.18. CONCLUSION: Most of the metal levels were above US EPA Maximum Contaminant Level MCL indicative of water pollution which may be of public health importance, and we, therefore, recommend water-quality monitoring.

Assessment of environmental distribution of lead in some municipalities of South-Eastern Nigeria.

Lead (Pb) levels were measured in roadside surface soils, dust particles and rain water samples from the urban cities of Enugu, Awka, Onitsha, Nnewi, Aba, Port Harcourt and Warri in Southern Nigeria in 2007 and 2008. Samples were collected during the dry season, while rain water samples were collected during the early rain (April-June), mid rain (July-August) and late rain seasons (September-October) for the two years. Soil samples were collected from traffic congested roads, dust was collected by tying a plastic basin on a pole 1.5 m above ground level and leaving it for 45 days. Rain samples were collected from three equidistant points. Samples were analyzed by AAS. The highest soil Pb of 120.00 +/- 0.00 and 80.36 +/- 0.00 mg/kg were reported in Onitsha for 2007 and 2008, respectively. Nnewi showed 33.40 +/- 0.01 and 4,238.29 +/- 0.00 mg/kg for 2007 and 2008. Aba had 22.56 +/- 0.01 and 21.28 +/- 0.00 mg/kg for 2007 and 2008. Higher concentrations were recorded for Nnewi and Port Harcourt in 2008 than in 2007. Enugu had more in 2007 while Awka had more in 2008. Dust Pb ranged from 0.13-0.49 mg/kg and 0.15-0.47 mg/kg for 2007 and 2008, respectively. Rain samples had the least Pb concentration, ranging from 0.103 +/- 0.000 to 0.163 +/- 0.046 mg/L. We may conclude that Nigerians are exposed to environmental Pb.

Nitrate and nitrite levels of potable water supply in Warri, Nigeria: a public health concern.

In this study, the authors investigated the nitrate and nitrite in different water sources (surface water, shallow well water, and borehole water) in the market and industrialized areas of Warri in the Niger Delta area of Nigeria. The authors' goal was to find the comparative levels of nitrates and nitrites from these two parts of the community. They selected five sampling sites from industrialized areas and another five from market areas. Nitrate and nitrites were determined using a DR/4000 UV-Vis spectrophotometer. The appreciable quantities of nitrates and nitrites found in these investigations have some public health implications. This study suggests that indiscriminate disposal of waste and poor sanitation may be additional contributing factors in the nitrate pollution of the water supply in the Niger Delta area of Nigeria.

Heavy metal hazards of pediatric syrup administration in Nigeria: a look at chromium, nickel and manganese.

Fifty different pediatric syrups were randomly sampled from patent medicine stores and pharmaceutical shops within Awka (Anambra State, Nigeria) between November 2007 and May 2008. Syrups were ashed before digestion using conc. aqua regia, HCl: HNO(3) (3:1). Chromium, nickel and manganese were assayed with AAS 205A. The highest levels of nickel were seen in Magcid suspension (4.13 mg/L) and Gaviron (0.79 mg/L) whereas lowest levels were found in Asco-J vitamin and Jawaron Syrup (0.01 mg/L). About 44.1, 73.6 and 20.6% of the sampled syrups made in Nigeria had non detectable levels of nickel, chromium and manganese respectively. Chromium levels ranged from 0.01 mg/L in Magcid suspension to 0.58 mg/L in emvite. Ferobin and Jawaron Syrup plus had 28.23 and 4.37 mg/L manganese, respectively. With the exception of Cephalexin Syrup, all the imported syrups had non detectable levels of chromium. The level of chromium in Cephalexin Syrup was 0.01 mg/L. About 68.8 and 43.7% of these imported syrups had non-detectable levels of nickel and manganese respectively. Nickel levels ranged from 0.01-0.09 mg/L in the imported syrups. Haemoglobin Syrup showed highest level of manganese of 0.36 mg/L whereas the lowest concentration was 0.02 mg/L in Cadiphen. Taken together the Nigerian made syrup samples had higher concentrations of the studied heavy metals. It is feared that ingestion of these syrups may constitute a significant source of heavy metal exposure to the children and should therefore be considered a public health problem. The public health hazards from ingestion of these syrups should be identified and disclosed by in-depth risk assessment studies.

Lead and cadmium levels of commonly administered pediatric syrups in Nigeria: a public health concern?

Fifty different pediatric syrups were randomly sampled from patent medicine stores and pharmaceutical shops within Awka, in Anambra State between November 2007 and May 2008. Syrups were ashed before digestion using conc. aqua regia, HCl:HNO(3) (3:1) and lead and cadmium were assayed with AAS 205A. Results revealed that 60 and 98% of the sample size had lead and cadmium respectively. The lead levels ranged from 0.01 in chloroquine to 1.08 mg/l in magcid suspension. The highest level of cadmium was seen in magcid suspension with concentration of 2.45 mg/l while lowest concentration of 0.01 in emzolyn and colipan. About 41.2% of the locally made syrup had none detectable levels of lead while all the syrup had detectable levels of cadmium. Lead levels ranged from 0.01 mg/l in cadiphen manufactured in Dholka, India to 0.09 in maxiquine made in England. About 68.8% of the imported syrups of the imported syrups had non detectable levels of lead. Chloramphenicol and zentel albendazole syrups had 0.60 and 0.88 mg/l of cadmium respectively. Bellis cough syrup showed the lowest level (0.01 mg/l) of cadmium. Only erythromycin suspension representing 6.3% had non detectable level of cadmium of the imported syrups. Due to the Cd and Pb levels found, we suggest that the behaviour scenario (here, self administration without medical assistance) should be properly taken under control. Along with this, contamination sources or vulnerable practices during syrups preparation should be also assessed in a tiered approach, towards the minimization of noxious presence in syrups and the promotion of quality of Nigerian-made products.

Comparison of the mopping ability of chemically modified and unmodified biological wastes on crude oil and its lower fractions.

Activated and unactivated powders of goat hair and coir (coconut husk) separated into two particle sizes were used to mop up spills of crude oil, diesel, kerosene and petrol. It was observed that the materials (sorbents) mopped up appreciable volumes of the hydrocarbon liquids (sorbates) within 90 min of contact. Activation, particle size of sorbents and molecular weight (chain length) of sorbates (hydrocarbon) are major determining factors. Carbonization and particle size enhanced the mopping ability as follows--carbonized 325 microm > uncarbonized 325 microm > carbonized 625 microm > uncarbonized 625 microm, thus activated sorbents with large surface area (small particle size) mopped more hydrocarbons than unactivated of the same particle size. The sorbates were mopped in the order--crude oil > diesel > kerosene > petrol. It was further observed that goat hair (keratin protein) with oleophilic and aquaphobic properties adsorbed more of all the hydrocarbons than coir at all sizes and treatment. Large quantities of the mopped oils were recovered by mere pressing while the waste sorbents with 0.5-2.0% leachable residual oil could be utilized as alternative to fire wood.

Metal contamination and infiltration into the soil at refuse dump sites in Awka, Nigeria.

Awka has been the site of increased human activities since it became a state capital in 1991. Because refuse dumps have hitherto been a disregarded environmental menace in Nigeria, the authors sought to find out how much of the current environmental metal pollutant load comes from refuse dumps. They investigated the metal contamination of the refuse dumps in Awka. The authors collected four soil samples (from the surface and from depths of 0.45 m, 0.90 m, and 1.35 m) from 5 dumpsites digested with nitric acid and perchloric acid, and they analyzed iron, sodium, arsenic, lead, magnesium, potassium, cobalt, zinc, nickel, copper, chromium, and cadmium by using an atomic absorption spectrophotometer. Sites A and C showed the highest levels of arsenic (2300 mg/kg) and lead (2467 mg/kg), respectively. Site D had highest level of both iron (72,200 mg/kg) and sodium (3561 mg/kg), whereas Site E had the lowest level of lead (572 mg/kg). The metal levels exceed the limits set forth by the US Environmental Protection Agency. This study suggests that the refuse dumps in Awka may increase the level of environmental heavy metals in Nigeria.