ghanaopendata/ghanaian-research-english huggingface dataset:
Heavy Metal Concentration in the Owere River at Konongo

The Owere River located in the Asante Akyem Central Municipality of Ghana is one of the major sources of water for household and farming purposes in the municipality. In recent times there has been indiscriminate small-scale gold mining activity in and around the river which has led to pollution of the river. The study was thus carried out to assess the levels of heavy metals and some physico- chemical parameters in the Owere River at Konongo in the Asante Akyem Central municipality of Ghana. Water samples from the Owere River were collected from upstream, midstream and downstream sites of the river and analyzed for some heavy metals: Arsenic, Cadmium, Iron, Lead and Mercury. pH, temperature, electrical conductivity (EC), alkalinity and turbidity were also determined Results indicated that the mean levels of Arsenic from upstream, midstream and downstream were 0.022± 0.024 (mg/L), 0.007± 0.002 (mg/L) and 0.012± 0.008 mg/L respectively. There was no significant difference in the Arsenic levels between and within the sites. The level in the upstream was above the WHO permissible limit of 0.01mg/L. The mean levels of Cadmium from the sites ranged between 0.027± 0.011 mg/L to 0.066±0.094 mg/L and were above the WHO permissible limit of 0.003 mg/L. The levels of Lead in the midstream and downstream were above the WHO permissible limit of 0.01 mg/L. The mean levels of iron from upstream, midstream and downstream were 4.907± 1.063 mg/L, 1.785± 0.350 mg/L and 2.015± 0.438 mg/L respectively. These levels were high compared to the WHO permissible limit of 1.0 mg/L for drinking water. There was a significant difference between the upstream and midstream water samples. There were no significant differences in the levels of mercury recorded at the three sites and were above WHO permissible limit of 0.001 mg/L except in the upstream where it was below instrument detectable limit. pH was within the range of 6.23± 0.316 to 6.78± 0.588. However the upstream water samples recorded the highest mean temperature of 25.9± 1.152°C. This was within the WHO acceptable limit of 25 to 28 °C for drinking water sample. Mean conductivity for the water samples ranged between 262.5± 80.328 µS/cm to 298.0 ± 14.508 µS/cm. Alkalinity levels were below WHO limit of 700mg/L. The levels recorded ranged between 74.3±0.424 to 107.2± 0.282 mg/L. Turbidity levels at all sites were high and above the WHO limit of 5NTU ranging between 55.5± 8.602 – 62.5± 6.390 NTU. The total dissolved solids levels at all the sites were within the WHO permissible limit of 1000 mg/L in drinking water. There was significant difference in the levels recorded at the sites. It is evident that the activities of the small-scale miners are affecting the quality of the water and thus the need for action to mitigate the effect of mining on the water body.

Source: KNUST
Heavy metal contamination assessment of groundwater quality: a case study of Oti landfill site, Kumasi

Environmentally friendly municipal solid waste management is the biggest problem facing several developing countries, including Ghana. Heavy metals pollution generated by landfill leachate has become increasingly concerned due to its potential impact on human health. This study assessed the pollution level and sources of heavy metal levels in groundwater, as well as evaluated the human health risk effect. The sampling technique and sample treatment were done based on the Standard Methods for the Examination of Water and Wastewater. The results suggested that the mean concentration of Pb, Fe, Cd, and Cr was above the acceptable limits of the World Health Organization for drinking water except for Zn and Cu. The heavy pollution index indicates contamination, while hazard index values at sites BH1 and W4 were greater than one, suggesting adverse health effects. However, the heavy metal pollution index values were less than the critical limit of 100 for drinking water. Multivariate analysis predicted that lithogenic and anthropogenic factors were the possible sources of water pollution of heavy metal in the Oti community. Thus, multivariate statistical techniques could be a beneficial tool for the evaluation of possible sources of heavy metal contamination. The high levels of heavy metals found in the Oti community suggested a considerable pollution of water by leachate percolation from the landfill site. The findings of the study, which can be used in areas under similar environmental conditions, can offer a valuable benchmark for the design of suitable approaches to manage groundwater resources by both local and national policymakers

Source: KNUST
Heavy metal contamination in canned fish marketed in Ghana

The concentrations of Pb, Zn, Fe, Cd, Mn and Hg in 46 canned fish samples of nine different brands purchased within Kumasi in the Ashanti Region of Ghana were determined using the Flame Atomic Absorption Spectrophotometer for Pb, Zn, Fe, Cd and Mn and direct mercury analyzer (DMA) for Hg. The ranges obtained for the elements analyzed in μg/g (wet weight) are as follows: Pb (0.058 - 0.168), Zn (0.010 - 0.370), Hg (0.088 - 0.410), Mn (0.001 - 0.057), Fe(0.990 - 32.607) and Cd, below detection limit in all the samples. The fish samples had Hg levels below the European dietary limit of 0.5 μg/g. Zinc levels were generally below the Food and Agriculture Organization (FAO) recommended limit of 40 μg/g. The concentration of lead in the canned fish was also below the MAFF guidelines of 2.0 μg/g. Also, based on the United States Environmental Protection Agency (US EPA) health criteria for carcinogens, there are no health risks associated with Pb concentrations in canned fishes analyzed. The result of the one-way analysis of variance (ANOVA) conducted on the data suggested no significant variations (P>0:05) in the concentrations of the metals in the same brands of canned fishes.

Source: KNUST
Heavy metal content of some local spices on the Ghanaian market

A spice is a vegetable substance of indigenous or exotic origin which is or has a hot, pigment taste, used to enhance taste of foods or to add to them the stimulant ingredients contained in them. They are sparingly used but frequently used in Ghanaian meals. Seven heavy metals were determined in some natural spices on the Ghanaian market. Four of the metals namely zinc (Zn), manganese (Mn), copper (Cu) and iron (Fe) are essential micronutrients and lead (Pb), cadmium (Cd) and mercury (Hg) are toxic metals. A total of eighty three samples comprising of fifteen spices were purchased from seven different markets at Asafo, Takoradi, Kaneshie, Ayigya, Makola and Tema. The spices were processed into the powdered form and subjected to a wet digestion procedure with a mixture of H2O, HCl, HNO3, HClO4 and H2SO4. Sample solutions were analyzed for Hg using a Mercury Analyzer Model HG-5000 and for the other metals using SOLAAR (S Series 711239 v1.23) Flame Atomic Absorption Spectrometer. The range of total Hg concentration (µg/g) for all the spices from all the markets is ND-0.031 (ND- not detectable), that for Cd also ranged from ND- 1.41. The range for Fe is 65.35-221.15, that for Mn is from 14.93-24.96. Zn ranged from ND -17.70 and finally Cu is 4.22-22.91. Pb was not detected in any of the samples analyzed. The amount of spice to be consumed in order to exceed the recommended daily intakes for the metals were calculated based on the recommended daily intake for the various metals. The amounts obtained were not unlikely to be consumed considering how sparingly they are used. Correlation analysis showed strong positive and negative correlation between the metals for the spices.

Source: KNUST
Heavy Metal Contaminants of Selected Culinary Herbs and Spices Available in some Ghanaian Markets

There is increasing global concerns about the safety of culinary herbs and spices available on market shelves. The Food and Drugs Authority (FDA) of Ghana rarely samples culinary herbs and spices on the market for its safety. To ascertain the safety of culinary herbs and spices on the Ghanaian market, the concentrations of Cd, Cr and Pb in ten commonly and frequently used culinary herbs and spices sampled from four large markets in the Accra and Kumasi Metropolis were determined. The dried samples were taken through wet digestion, in triplicate, with a 12 ml HCl and HN03 acid mix to obtain clear solutions which were subsequently analyzed with AAS. All the samples studied contained no detectable traces of Cd. Five of the ten sampled culinary herbs and spices contained detectable traces of Pb, whilst two of the ten contained detectable traces of Cr. Turmeric recorded the highest mean Cr concentration (0.42± 0.03 mg/kg). The mean concentrations of Pb present in five of the sampled herbs and spices exceeded the maximum permissible limit set by the WHO at 0.1 mg/kg (Anise; 8.95± 0.05 mg/kg, Cloves; 5.50±0.05 mg/kg, Fennel; 6.52±0.06 mg/kg, Rosemary; 4.55±0.06 mg/kg and Turmeric 0.85 ±0.08 mg/kg). The results indicate that the culinary herbs and spices on the market may contain high levels of heavy metals which are a potential risk to human health.

Source: KNUST
Heavy metal contents of soil and citrus grown in selected districts of Ashanti Region, Ghana.

Soil and edible citrus fruit samples from two mining districts (Obuasi and Asante Akim North) and two non-mining districts (Ejisu-Juaben and Sekyere West) of Ashanti Region, Ghana were assessed for their relative Zn, Cu, Fe, Cd, Pb and Mn contents and to ascertain whether citrus fruit heavy metal contents are within permissible limits. Representative areas were selected from these sites with sampling depending on the variability of the terrain. From each sampling unit, ten (10) soil cores/slice were taken from 0-15, 15-30 and 30-45 cm soil depths separately, each depth thoroughly mixed by hand in plastic bucket and sub-samples taken for laboratory analyses. Twenty-four edible citrus fruit samples were also taken from four trees at each sampling unit for laboratory analyses. A 0.1 M EDTA solution was used to extract the metals in soil. The citrus fruit pulp was digested in H2SO4/HCl mixture after evaporation to dryness. Mining activities, use of agrochemicals in agriculture production and vehicle exhaust fumes were proposed as the main sources of heavy metals. The accumulation of these metals in these municipalities were in the order Obuasi > Sekyere West > Asante Akim North > Ejisu-Juaben. There were significant differences of the selected metals levels in citrus fruits and soils from the four districts. Soils of low pH had higher citrus fruit uptake of heavy metals than those of moderate to high pH while soils of high organic matter content also had high metal content but low citrus uptake. There were either strong negative or positive correlations between soil and citrus fruit heavy metal contents. Though the heavy metal load of soils from all the four municipalities were below the permissible limit set by the Dutch standards for soil contamination assessment, the levels of citrus fruit Zn and Pb of all the four districts were above the permissible limits set by FAO/WHO while Cd in citrus fruit of Obuasi, Asante Akim North and Sekyere West were above the permissible limit. Therefore, consumption of citrus fruit from the selected districts could pose health hazards to humans as at the time of the study. Further research is required to determine the heavy metal content of soil and citrus fruit grown in other citrus-growing regions of the country as well as socio-economic and health status of neighbouring communities for sustainable citrus production in Ghana.

Source: KNUST
Heavy metal exposure and symptoms of respiratory infection among children under-five (5) residing near an open dumpsite: a cross-sectional study at Abokobi

The purpose of the study was to assess the prevalence of self-reported symptoms of Acute Respiratory Infection(ARI) defined as Acute Upper Respiratory Infection (AURI) and Acute Lower Respiratory Infection(ALRI), the levels of toxic metals in biological media (blood), and hand washed water among children under five (5) residing near Abokobi dump site in the Ga-East Municipality. Participation in the study was voluntary; based on that, a population of 200 children under five (5) and their parents residing within 200meters around the dumpsite were recruited as participants for the study. Descriptive statistics was used to present data. It came out that, the proportion of self-reported symptoms of acute upper respiratory infection (AURI) and acute lower respiratory infection (ALRI) was high in all children respectively. Cadmium was high in children aged 0-2years than 2-4 years and Lead was the same in ages 0-2years and 2-4 years in biological media (blood). Lead was the same in ages 0-2 years and 2-4 years while Cadmium and Mercury were high in Ages 2-4 years than ages 0-2 years in the handwashed water. There was significant association between residual levels of Arsenic in blood samples and symptoms of AURI. Similarly there was significant association between residual levels of Cd and symptoms of ALRI. However, there was no significant association between residual levels of the other toxic metals in blood samples and symptoms of AURI and ALRI. The study therefore recommended Parents should ensure regular medical checkup for children who live close to dumpsites for detection of symptoms of diseases to avert any health risk they may be exposed to. Ministry of Health should intensify public education on good practices in child care to avert the development of preventable diseases such as acute respiratory infections. The Ministry of Local Government through the Ga-East Municipal should create awareness on proper waste management practices. Finally, Local Government Ministry and the Ministry of Sanitation and Water Resources should permanently ban or prohibit the use of the dumpsite.

Source: KNUST
Heavy metal health risk assessment and microbial quality of locally milled ready-to-eat tomato in Tamale, Ghana

This study was carried out with the aim to assess the microbial quality and risks associated with the intake of four heavy metals i.e., lead (Pb), cadmium (Cd), arsenic (As) and mercury (Hg ) via the consumption of ready-to-eat tomato sauce from four (4) milling sites in the Tamale Metropolis . Twelve (12) samples of ready-to-eat tomatoes sauce were collected in triplicates from four (4) milling sites. The samples were digested with nitric and perchloric acid mixture (3:1) and analyzed using Atomic Absorption Spectrometer (AAS). Average concentrations (± SEM) of Cd, Pb, As and Hg in ready-to-eat tomato were found to be 0.1062±0.03330, 0.37085±0.19758, 0.00025±0.00004 and 0.00367±0.00068 mg/kg respectively. The concentrations of Cd and Pb were found to be significantly higher than the tolerable limits. However, concentration of Hg and As were within the permissible limits and thus safe to consume. Generally the level of health risk associated with exposure to the four heavy metals (Cd, Pb, As and Hg) through ingestion of the ready-to-eat tomato was low and does not increase for example cancer risk over a lifetime (70years). However, the mean dietary intake for Cadmium (15.61 µg/kg) and Mercury (47.57 µg/kg) were higher than the Provisional Tolerable Weekly Intake (PTWI) body of 2.5 and 25 µg/kg respectively. Analysis of the food samples also revealed mean total bacterial count to be 7.00 ± 0.46 log10 cfu/g. The minimum and maximum bacterial count ranged from 6.7 ±0.12 log 10 cfu/g to 7.2±0.9 log10 cfu/g respectively. The bacterial species encountered included Bacillus sp. and Staphylococcus aureus. Overall 66% of the samples tested Positive for Escherichia coli, this could be due contaminated processing water, or cross contamination of raw materials and cooked food by equipment or vendors. All the samples had bacterial counts higher than the acceptable levels and thus pose health risk to the local population who regularly patronize them.

Source: KNUST
Heavy metal pollution and the role of inorganic nanomaterials in environmental remediation

Contamination of water and soil with toxic heavy metals is a major threat to human health. Although extensive work has been performed on reporting heavy metal pollutions globally, there are limited review articles on addressing this pernicious phenomenon. This paper reviews inorganic nanoparticles and provides a framework for their qualities required as good nanoadsorbents for efficient removal of heavy metals from water. Different inorganic nanoparticles including metals, metal oxides and metal sulfides nanoparticles have been applied as nanoadsorbents to successfully treat water with high contaminations of heavy metals at concentrations greater than 100 mg l−1 , achieving high adsorption capacities up to 3449 mg g−1 . It has been identified that the synthesis method, selectivity, stability, regeneration and reusability, and adsorbent separation from solution are critical parameters in deciding on the quality of inorganic nanoadsorbents. Surface functionalized nanoadsorbents were found to possess high selectivity and capacity for heavy metals removal from water even at a very low adsorbent dosage of less than 2 g l−1, which makes them better than conventional adsorbents in environmental remediation

Source: KNUST
Heavy Metal Quality And Safety Of Plantain From Selected Mining Towns

Heavy metal pollution has pervaded many parts of the world especially developing countries such as Ghana. Heavy metals can enter the food chain through industrial mining activities. Plantains (Musa sp) are important staple foods in Ghana. They are rich in dietary energy and also prove good quality diet. The relationship between mining and the presence of these heavy metals in plantain was researched into. The Inductively coupled plasma mass spectrophotometer was used to determine levels of Lead (Pb), Arsenic (As) and the Varian hydride system atomic absorption mass spectrophotometer to determine the level of mercury (Hg) in sixteen samples of plantain in three towns Anyinam, Kwabeng and Kibi in the Eastern region of Ghana. The mean levels in milligram per kilogram of the heavy metals from Anyinam were Pb (0.0025), Hg (0.1194), As (0.0022), from Kwabeng Pb (0.0011), Hg (0.1287), As (0.0010) and from Kibi, Pb (0.0256), Hg (0.1125), As (0.0018).The results indicate presence of mercury in all the samples tested. Only Kibi indicated high levels of Pb which exceeded the Codex recommended levels of 0.01mg/kg in fresh fruits and vegetables. The levels of arsenic were generally low. This study provides an assessment of the levels of mercury, lead and arsenic pollution in mining towns in the Eastern region whiles identifying policy recommendations for standards development in Ghana.

Source: KNUST
Heavy metals and pesticide residues in honey from the major honey producing forest belts in Ashanti, Brong Ahafo and Western Regions of Ghana

The purpose of this work was to determine the concentrations of heavy metals and pesticides residues in honey. In all forty five honey samples were purposively collected from Ashanti, Brong Ahafo and Western Regions of Ghana. QuEChERS method, a multiresidual method for analysis of pesticide residues in low –fat matrix was employed in the extraction procedure. Varian CP-3800 Gas Chromatograph with a CombiPAL Autosampler, equipped with electron capture detector for synthetic pyrethroids and Organochlorine pesticides while pulse flame photometric detector for organophosphate were used. Aldrin, γ-HCH, β-HCH, Σendosulfan, cyfluthrin, cypermethrin, deltamethrin, permethrin methoxychlor, ΣDDT, chloripyrifos, fenvelerate, malathion, dimethoate and diazinon were all detected at the concentration of 0.01 with the exception of cyfluthrin and permethrin which were detected at 0.02 and 0.04 mg/kg respectively, in each of the pesticides. All the pesticides residues detected were below the respective maximum residue limit. Hence honey samples analyzed do not pose any health risk to the consumer. For the heavy metal analysis using AAS, the concentrations were in the order as: Cd 0.02 <Zn 0.22 < Pb 0.84 < Fe 2.30 < Cu 3.23 mg/kg. Cadmium recorded the lowest concentration 0.03 mg/kg whilst Cu recorded the highest concentration of 3.23 mg/kg.

Source: KNUST
Heavy Metals Contamination and Distribution in Surface Water and Sediment of The Aboabo Stream, Ahafo Region, Ghana

Activities of illegal small-scale miners promote continual introduction of wide pollutants into the Aboabo stream. Their toxicity poses health threats to the inhabitants of Krapoo village in the Ahafo Region, Ghana. The study assesses the impacts of illegal small-scale mining activities on the water quality of the stream. Levels of physico-chemical and microbiological parameters were determined using standard methods. Samples of sediment, water and plant were acid-digested with aqua-regia. Total Arsenic and Total Cadmium were analysed using Flame Atomic Absorption Spectrophotometer (FLAAS) whiles Total Mercury was analysed using Cold Vapour Atomic Absorption Spectrophotometer (CV-AAS). Turbidity, faecal coliforms and E-coli readings exceeded permissible limit of 5NTU and 0MPN/100ml respectively by Ghana’s Environmental Protection Agency (GS 1212) and World Health Organisation (WHO). Temperature, Electrical Conductivity and pH values were within the limit of <30oC, 1500μs/cm and 6.5-85 respectively at both seasons. Total suspended solids readings at the midstream were higher than the permissible limit. However, levels of total dissolved solutes and dissolved oxygen recorded, were below the limit. The sediments were also heavily polluted with Mercury, Arsenic and Cadmium. Alchornea cordifolia, Chromolaena odorata and Spigella anthelmia growing within the stream were taken to assess their efficiency in removing the heavy metals from the stream. It was observed that the plants species had bioaccumulation factor (BF) greater than 1 for cadmium. Alchornea cordifolia was the only plant with BF greater than 1 for mercury. The plants species are potential hyper accumulators for mercury and cadmium hence are suitable for phytoremediation.

Source: KNUST
Heavy metals concentration in cabbage {brassica oleracea), lettuce [lactuca sativa)t and spring onion {allium cepa) grown along some urban rivers in the Kumasi Metropolis

This study assessed heavy metals (lead, cadmium, arsenic, nickel, copper, iron and zinc) concentration in lettuce, cabbage and spring onions grown along River Subin and its tributaries; Rivers Wiwi, Oda and Sisa which are extensively used by urban vegetable farmers in Kumasi to irrigate their vegetables. Atomic Absorption Spectrophotometry was used to evaluate the levels of heavy metals in the vegetable samples at four sitps along the river banks. There were no well defined trends in heavy metals concentration in all the vegetable samples. However, heavy metals in vegetables at the KNUST and Ayeduase sites were relatively higher compared to the Sepetimpon and Ofoase sites. Levels of nickel, zinc, copper and iron in all three vegetable samples (lettuce, cabbage and spring onion) at the four sites were below the WHO/FAO recommended guideline levels of 67.90 mg/kg for nickel, 99.40 mg/kg for zinc, 73.3 mg/kg for copper and 425 mg/kg for iron. However, comparing the three vegetables in terms of levels of heavy metals accumulation, averagely-nickel was highest (0.192mg/kg) in spring onion, zinc- (2.85mg/kg) in spring onions, copper (0.355mg/kg) in spring onion and iron (13.91 mg/kg) in cabbage. Levels of cadmium, lead and arsenic in all three vegetable samples were above the WHO/FAO recommended guideline levels of 0.2 mg/kg, 0.3 mg/kg and 0.43 mg/kg, respectively. Cadmium was highest (1.06mg/kg) in spring onion, lead (1.57mg/kg) in spring onion and arsenic (4.14mg/kg) in lettuce. The presence of cadmium, lead and arsenic above the recommended WHO/FAO guidelines levels presents a potential hazard to the health of consumers.

Source: KNUST