WHO Maximum Permissible Limit Research Articles

Phytochemical and Heavy Metal Screening of Fura da Nono, Ciklavit®, Katoka Mixtures®, and Yoyo Bitters®

Background: Evaluation of the phytochemicals and heavy metals contained in four commonly consumed beverage and herbal products in Nigeria, was investigated. This was to ascertain the health benefits as well as potential for toxicity that may be associated with the consumption of these products. Methods: The samples studied are Fura da Nono, Ciklavit®, Katoka Mixtures® and Yoyo Bitters®. The phytochemical screening of each product was done using standard procedures. The heavy metals screening was done using Agilent®720 Inductively Coupled Plasma -Optical Emission Spectroscopy machine (ICP-OES). The Hazard quotient and Index were assessed using appropriate equations in line with United States Environmental ProtectionAgency (USEPA). Results: All phytochemicals tested were found in Fura da Nono except Steroids and Terpenoids.Also, all the tested phytochemicals were detected in Ciklavit® except Alkaloids and Phlobatannins. Both Katoka Mixtures® and Yoyo Bitters® contained all other phytochemicals except Phlobatannins. Quantitatively, Fura da Nono was high in Cardiac glycosides, and Ciklavit® was found to be high in Flavonoid content. Both Katoka Mixtures® and Yoyo Bitters® are high in Phenols. The results of the heavy metal analysis revealed different concentrations (ppm) of arsenic, mercury, lead, cadmium, zinc, manganese, copper and nickel in the four products. Arsenic was not detected only in Fura da Nono. The heavy metal concentrations obtained were all within WHO maximum permissible limits. Further analysis for potential non-carcinogenic health risk using Hazard quotient on each of the four toxic heavy metals (arsenic, mercury, lead and cadmium) and Hazard Index (HI) on the same toxic heavy metals revealed that by the United States Environmental ProtectionAgency (USEPA) threshold value of HI ≤1, Yoyo Bitters® (0.4684) and Ciklavit® (0.7870) had the lower and safer values for combined heavy metal risk while Katoka Mixtures® (0.9908) and Fura da Nono (1.4144) had the highest. Conclusion: The phytochemical screening of the investigated products showed that the commonly consumed food drink and herbal products, are rich in phytochemicals. Even though the heavy metal screening indicates a fairly positive safety margin for three of the products. Caution should therefore be exercised in the use of these products.

Potential Health Risk Evaluation of Heavy Metal Exposure from Consuming Commercially Produced Food Seasonings in Enugu, Nigeria

Heavy metals are inherently non-biodegradable elements of the earth's crust that collect and remain in the ecosystem in perpetuity due to both human and natural activity. Their contamination in seasonings remains a public health concern because of the frequency of use. Prolonged exposure to these heavy metals is a severe health risk worldwide. This study evaluated the potential health risk of heavy metal exposure from consuming commercially produced food seasonings in Enugu, Nigeria. Thirty (30) commercially produced food seasonings were selected by simple random sampling and grouped into five (5) according to different batches. Atomic absorption spectroscopy was used to analyze arsenic, cadmium, lead and nickel. The level of arsenic in group SA(1.28±0.21mg/kg), SB(1.73±0.31mg/kg), SC(1.13±0.17mg/kg), SD (2.11±0.20mg/kg) were observed to be above (1.00mg/kg), the WHO maximum permissible limit. Cadmium levels in SA (0.36±0.01mg/kg) were observed to be above (0.30 mg/kg), the WHO maximum permissible limit. The estimated daily intake, hazard quotient and hazard index of the metals were within the normal range. The presence of heavy metals above WHO permissible limits in commercially produced food seasonings should be a public health concern. To protect the population's health, producers, retailers, and vendors of seasonings should be informed of the hazards of exposing their products to heavy metal contamination. Continuous surveillance of commercially produced food seasonings for heavy metal contamination is recommended.

Combining multi-isotope technology, hydrochemical information, and MixSIAR model to identify and quantify nitrate sources of groundwater and surface water in a multi-land use region.

Accurate identification of nitrate(NO3-) sources is the premise of non-point source pollution control in watersheds. The multiple isotope techniques (δ15N-NO3-, δ18O-NO3-, δ2H-H2O, δ18O-H2O), combined with hydrochemistry characteristics, land use information, and Bayesian stable isotope mixing model (MixSIAR), were used to identify the sources and contributions of NO3- in the agricultural watershed of the upper Zihe River, China. A total of 43 groundwater (GW) and 7 surface water (SFW) samples were collected. The results showed that NO3- concentrations of 30.23% GW samples exceeded the WHO maximum permissible limit level, whereas SFW samples did not exceed the standard. The NO3- content of GW varied significantly among different land uses. The averaged GW NO3- content in livestock farms (LF) was the highest, followed by vegetable plots (VP), kiwifruit orchards (KF), croplands (CL), and woodlands (WL). Nitrification was the main transformation process of nitrogen, while denitrification was not significant. Hydrochemical analysis results combined with NO isotopes biplot showed that manure and sewage (M&S), NH4+ fertilizers (NHF), and soil organic nitrogen (SON) were the mixed sources of NO3-. The MixSIAR model summarized that M&S was the main NO3- contributor for the entire watershed, SFW, and GW. For contribution rates of sources in GW of different land use patterns, the main contributor in KF was M&S (contributing 59.00% on average), while M&S (46.70%) and SON (33.50%) contributed significantly to NO3- in CL. Combined with the traceability results and the situation that land use patterns are changing from CL to KF in this area, improving fertilization patterns and increasing manure use efficiency are necessary to reduce NO3- input. These research results will serve as a theoretical foundation for controlling NO3- pollution in the watershed and adjusting agricultural planting structures.

Quality of Water from Hand-Dug Wells in Nembe Town, Bayelsa State, Nigeria

This study examined the quality of water supply from hand-dug wells in Nembe town, Bayelsa State using sample survey design. Data was obtained from primary sources. To assess if the quality of groundwater supplied in Nembe town is safe for domestic and drinking purposes, the physico-chemical and microbial status of the groundwater were studied. Nembe town was stratified into ten neighbourhoods and a total of ten (10) hand dug well water samples was randomly collected from each of the sampled ten neighbourhoods and analyzed for twenty-one (21) paramaters in the month of November 2019. These samples were sent to the laboratory for physico-chemical and microbial analysis. The results of the study revealed that physico-chemical paramaters such as Total Dissolved Solids (TDS), Total Suspended Solids(TSS), Sulphate (So4-2), Bicarbonate (HCo3-), Calcium (Ca), Sodium (Na), Manganese (Mn), Electrical Conductivity (EC), Iron (Fe), Chloride (CL), Nitrate (NO), Salinity, Total Alkalinity (TA) and Magnesium (Mg) are all within the permissible level of WHO and NESREA drinking water standards. Groundwater in the area have turbidity and potassium levels higher than the WHO and NESREA maximum permissible limits for drinking water standard. All the sampled hand dug wells have pH value within the permissible limit of drinking water except one which had pH value of 6.48 and considered too acidic for human consumption. Based on hardness, 70% of the groundwater samples are slightly hard water to hard water in nature. The result of the microbial analysis showed the presence of total coliforms, Total bacteria counts and fungi in all the hand dug wells. The ANOVA statistical tool was employed in testing the stated hypothesis and the results show that there is no significant spatial variation in the physico-chemical properties of water in the study area and that there is a significant spatial variation in the microbial properties of water in the study area. The result of the study was conclusive evidence that all the hand dug wells studied are not safe for domestic purpose especially for drinking as they were affected by some physico-chemical and biological parameters. Hence the affected wells call for periodic monitoring and treatment to improve the quality of the water.

Evaluation of quality of some commonly used herbal medicinal plants in local markets of FCT, Abuja, Nigeria

The safety of herbal medicines has become a major concern to both national health authorities and the general public. Hence their production, quality, distribution and use are regulated. Some medicinal plants commonly used for malaria, diabetes and Tuberculosis and respiratory conditions were evaluated for qual-ity. The objective of the study is to assess some quality specifications, physicochemical and heavy metals of some medicinal plant extracts. The samples were identified, purchased, processed and analyzed using appropriate standards methods specified by WHO and AOAC; while the heavy metals content was analyzed using Atomic Absorption Spectrophometer (AAS). All the analyzed samples passed WHO permissible limit established for heavy metals content, however 42.8 and 21.4% of the samples failed moisture and ash con-tent permissible limits respectively. High level of moisture content will favor microbial and fungal growth and shortens shelf-life of the samples. The WHO maximum permissible limits for moisture and ash content are ≤15 and ≤8. The ash content was also above standard permissible limit in 80% of the samples, this could be associated to improper handling that has resulted to introduction of inorganic substances such as silica and other inorganic matters. The levels of heavy metals content were all below the WHO maximum per-missible limits. The moisture, ash and heavy metals are among the important parameters of medicinal plants that require frequent routine monitoring in order to ensure safety.

Heavy metals monitoring on NIPRD Botanical Garden

Study of the level of heavy metals (Copper, Chromium, Lead and Zinc) in soil, organic manure and medicinal plants obtained from NIPRD Botanical Garden was carried out. The objective is to determined level of safety of the Botanical Garden towards realizing safe phytomedicine. Samples were collected, processed and analyzed for the specified heavy metals with Atomic Absorption Spectrophotometer using standard methods. The results obtained indicated the presence of Cu and Zn in the medicinal plants (8.17±3.36 mg/kg and 34.70±15.20 mg/kg), soil (13.43±1.91 mg/kg and 24.00±4.86 mg/kg) and the organic manure (33.50±0.40 mg/kg and 59.45±0.80 mg/kg), while Cr and Pb were not detected. The mean concentration of Cu and Zn obtained in soil, medicinal plants and organic manure at sampling sites A, B, C and D were below WHO and US (EPA) maximum permissible limits. In conclusion, NIPRD Botanical Garden is not polluted with the studied heavy metals; therefore, it is safe for domestication of medicinal plants.

Health Risks for a Rural Community in Bokkos, Plateau State, Nigeria, Exposed to Potentially Toxic Elements from an Abandoned Tin Mine.

The past mining activities in Bokkos Local Government Area (LGA) were performed in an uncontrolled way and gave rise to many abandoned ponds now serving as domestic and irrigation water sources. Past research focused mainly on the environmental impact, and we show for the first time what the human health risk through consumption of contaminated food crops is in these communities. This study was designed to determine the level of Potentially Toxic Elements (PTEs) contamination in pond water, soil, and food crops and assess the health risk of inhabitants in the abandoned tin mining community in Bokkos LGA. Samples of the mining pond water, soil, and selected food crops from farms irrigated with the pond water: bitter leaf (Vernonia amygdalina), pepper (Piper nigrum), okra (Albelmoschus esculentus), maize (Zea mays), sweet potato (Ipomoea batatas), and Irish potato (Solanum tuberosum) were analyzed for each of the eight PTEs (viz. Cu, Cr, Fe, Mn, Ni, Zn, Cd, and Pb) using inductively coupled plasma optical emission spectrometry (ICP-OES). The results obtained showed that the levels of all the PTEs analyzed in the soil, pond water, and selected food crops except for Fe and Mn in soil and Cd in sweet potato were greater than their corresponding background area values (p < 0.05). Also, the mean concentrations of all the PTEs except for Cu in pond water were significantly (p < 0.05) higher than the WHO maximum permissible limit. With the exception of Fe, Ni, and Zn for pepper and okra, Cu and Fe for maize grains as well as Cu, Ni, and Zn for sweet and Irish potatoes and Fe and Cd for sweet potato, the mean concentrations of PTEs in the food crops were significantly higher than WHO maximum permissible limit. The EF values of Cd (0.39); Cu (3.59) and Ni (2.81); Cr (9.38) and Pb (17.84); and Mn (178.13) and Zn (83.22) classified the soil as minimally, moderately, significantly, and extremely highly enriched, respectively. The PI values of all the PTEs in the soil studied were all greater than 5, indicating that the soils were severely contaminated. There was evidence that food crops significantly bioaccumulated PTEs either as a result of contaminated soil and/or irrigation water. The bioaccumulation was not uniform and was dominated by transfer from the polluted irrigation water. The bitter leaf, okra, and to some extent maize had the highest transfer of PTEs, and Mn, Cu, and Zn had the highest bioaccumulation in the food crops investigated. The hazardous index (HI) for the eight PTEs through the consumption of food crops was 107 for children and 33 for adults which greatly exceeded the recommended limit of 1, thus indicating that possible health risks exist for both local children and adults. For every PTE, the values of HI for children are many-fold higher than those for adults, which is of particular concern due to the high HI values for Pb found for maize consumption, a typical staple food. The cancer risk values for Cr and Ni for all the food crops were within 10-3-10-1 which is several fold higher than the permissible limits (10-6and < 10-4) indicating the high carcinogenic risk. It can be concluded based on the results and risk assessment provided by this study that human exposure to mining pond water and soil in farms around the mining pond through the food chain suggests the high vulnerability of the local community to PTE toxicity. Long-term preventive measures to safeguard the health of the residents need to be put in place.

Evaluation and Distribution of Selected Polychlorinated Biphenyl Congeners and Triclosan in Soil, Sediment and Surface Water System: A Case Study of Ojutu River, Osun State, Nigeria

ABSTRACT This study evaluated the presence of seven-selected polychlorinated biphenyls and triclosan in the Ojutu River, Osun State Nigeria. The soil, sediment and surface water at five different sampling sites were investigated following the standard analytical procedure. The maximum concentration of targeted PCBs in soil, sediment and water are; 1.02 µg/g, 0.6490 µg/g and 0.02981 µg/mL respectively. While triclosan has 0.0562 ng/g, 0.0457 ng/g and 0.001070 ng/mL in sediment, soil and water samples respectively. The concentrations of some of the selected PCB congeners and triclosan were significant in sediment and soil samples across the sites while the majority analytes showed no significant differences in water samples across the sites. The parameters investigated were found within the WHO maximum permissible limit therefore the water could be considered less susceptible to these pollutants. Other contaminants such as personal care products, pharmaceuticals, heavy metals and micro-pollutants as well as pollution levels associated with microbial load are worthy of investigation to know the actual state of the river for the safety of aquatic lives and the health of humans who depends on this river.

Investigation of the Concentration of some Metals in Blood Cockle (Senilia senilis) and Oyster (Crassostrea gasar) from Bonny Estuary and Assessment of the Human Health Risk Associated with their Consumption

There is a growing concerns over the health risk of consuming seafood contaminated with poisonous metals from human activities. This study examined the concentration and human health risk of Pb, Cd, Cr, Ni, Co, Zn, V and Hg associated with the consumption of blood cockle (Senilia senilis) and oyster (Crassostrea gasar) from Bonny Estuary, Rivers state Nigeria by analyzing the levels of the selected metals using Atomic Absorption Spectrometer Model A 200 AA. Data were used to calculate the non-carcinogenic health risk using Daily Intake Rate (DIR) Target Hazard Quotient (THQ) and Hazard Index (HI). The results showed variations in the concentration of the different heavy metals in the two shellfish. The trend of the metal concentrations in decreasing order was: Crassostrea gasar &gt; Senilia senilis. Levels of metals in Senilia senilis, were all below the WHO and FAO permissible limit for fish. Also, all metals except Pb were below the WHO maximum permissible limit in Crassostrea gasar. The DIR (9.4684E-06 - 0.00281); THQ (8.286E-07 – 1.842E-04) and HI (2.519E-05 -2.595E-04) for all metals were below one indicating no risk for non-carcinogenic effects individually and collectively. The shell fish analyzed from the Bonny Estuary are free from potential human health hazards from heavy metals. However, continuous monitoring of levels of metals in fish from the estuary is recommended.

Seasonal Variations of Polycyclic Aromatic Hydrocarbons in the Muscle Tissue of Silurus triostegus Heckel, 1843 from Derbendikhan Reservoir

Derbendikhan reservoir is located on the southeast of Sulaimani city 35° 6' 35" N, 45° 41' 20" E, it is the second largest reservoir in the Iraqi Kurdistan region at an altitude of 485 m above sea level. It was formed when the dam was constructed in1956–1961. The area is about 114.30 km2 with the maximum depth of 75.0 m. Silurus triostegus is one of twenty genera of fish that are endemic to Derbendikhan reservoir, Seasonal sampling for 64 samples of fish for 11 sites was carried out from November 2018 to August 2019, Fishing was performed with gill nets of 18, 25, 33, 40, and 55 mm inner mesh sizes. The goal of this research is to determine the level of PAHs in, fish muscle of Silurus triostegus, because fish as an important food source for man and it’s the primary indicator of the toxification of streams and lakes, on the other hand, PAH will cause many health problems including cancer, in addition, this information may be used as a database for any environmental modeling in the future, this study was carried out. Results indicate increasing in PAH in the spring season, although, as a result of fishing activities using old boats and ships at a high rate, in addition to the changes of water temperature in different season. PAH in the muscle of fish (0.098–1.271 μg/g) were above the WHO maximum permissible limit of 0.001 μg/g. The main conclusion is that the fish muscle contains high amounts of PAHs through bioaccumulation and biomagnifications. Finally, the lake needs immediate attention to reduce improper waste disposal and improve on measures against indiscriminate dumping of petroleum products and domestic waste in the water, which are the major sources of petrogenic and pyrogenic PAHs should be minimized, and the treatment of the sewage before its discharge into the reservoir.

Physicochemical, Heavy Metals and Microbiological Assessment of Wastewater in Selected Abattoirs in Ekiti State, Nigeria

This study was on the assessment of wastewater in three selected abattoir environments in Ekiti State, Nigeria. The selected abattoirs are Atikankan Abattoir, Ikere – Ekiti Abattoir and Iworoko Road Abattoir. Wastewater samples were collected in the three locations. The physicochemical, heavy metal analysis, and microbial analysis of the samples were carried out using standard methods. The six heavy metals analyzed were (Cadmium, Chromium, Nickel, Iron, Lead, and Manganese) using Atomic Absorption Spectrometer (AAS, VGP210). The result showed that the physicochemical parameters: Turbidity (96.83 – 182.26 NTU); Electrical Conductivity (948.67 – 1262.00 μScm-1); BOD (527.42 - 640.66 mg/L); COD (850.67 - 1033.33 mg/L); Phosphate (14.70 - 18.20mg/L) and Nitrate (50.73 - 77.85 mg/L) samples collected were above the WHO maximum permissible limits. Heavy metal analysis of the samples revealed that the concentrations of (Cd, Fe, and Pd) were higher than the FAO/WHO permissible limits while those of Cr, Ni, and Mn were within the safe limits. The microbial analysis revealed a high population of bacteria and fungi from all the samples collected from the three locations. In general, if the wastewater from these abattoirs is not treated before being discharged into water bodies, it could pose a great health risk to the environment.

Assessment of surface water quality of Onuiyieke river in Imo State, Nigeria

This research aimed to assess the surface water of Onuiyieke River to ascertain its quality status. Measurements were made on samples collected from seven locations with 500ml sample bottles according to standard methods. Samples for heavy metals were collected in 250ml bottle and fixed with concentrated HN03. Descriptive analysis, variation plots, ANOVA, Duncan Multiple Range tests, Principal Components Analysis (PCA), Pearson Correlation (r) and Water Quality Index (WQI) were used to analyze data. Mean values of the parameters obtained were: Total Suspended Solids (TSS) 198.19 ± 80.93mg/L; Electrical Conductivity (EC) 331.81 ± 59.78µ; Turbidity 18.84 ± 2.22 NTU; Nitrate ions 14.77 ± 0.92mg/L; Dissolved Oxygen (DO) 6.58 ± O.22mg/L and Biological Oxygen Demand (BOD) 1.77 ± 0.10mg/L. Mean values of the Trace Metals obtained were: Iron (Fe) 1.93 ± 0.23mg/L; Magnesium (Mg)0.22 ± 0.02mg/L and Calcium (Ca) 15.15 ± 1.87mg/L while the mean value of Faecal Coliform was 1.91 ± O.10MPN/100. pH, EC, TSS, BOD, turbidity, N03-, Ammonia, Fe and Faecal coliforms exceeded the NESREA and WHO maximum permissible limits. There were significant spatial differences in levels of TDS, EC, NO3, NH3, DO and Faecal coliforms (Sig F=0.000 to 0.039) and significant temporal differences in levels of PO43- (Sig F= 0.078 to 1000) between the control and other locations at p&lt;0.05. Four Principal Components (PCs) formed the extraction solution with a cumulative percentage variability of about 77.67%. The Water Quality Index revealed that the rating for the water quality across the sampling locations was between excellent and unsuitable. Appropriate monitoring procedures for the sustainable development of the river should also be put in place.

Assessment of heavy metal content of commonly consumed herbal medicines in Sindh, Pakistan.

In Pakistan, herbal medicines are extensively consumed by a major portion of people for the treatment of numerous ailments. Nowadays, the contamination of heavy metals in herbal medicines is a serious concern due to its toxic effects on human health. In the present study, quantitative evaluation of four heavy metals, namely, iron (Fe), cadmium (Cd), nickel (Ni), and copper (Cu), was carried out in forty herbal medicines, frequently sold in the markets of Sukkur and Khairpur, Pakistan, without any quality assurance. Conventional wet acid digestion method was used for the dissolution of samples, and the concentration of heavy metals was determined by using flame atomic absorption spectrometry. Diverse concentration of metals was observed in different herbal medicines. The levels of Fe, Cd, Ni, and Cu were in the range of 30.3-798 mg/kg, 0.002-0.007 mg/kg, 1.52-27.3 mg/kg, and 15.2-194 mg/kg, respectively. The findings of our study were also compared with the WHO maximum permissible limits. It was observed that the concentrations of these heavy metals in most of the analyzed samples were within the permissible limits set by the WHO. Only a few samples of herbal medicines exceeded the recommended levels of Ni and Cu. These medicines should be regularly checked for quality assurance to avoid chronic exposure of metal to human beings.

Health Risk Assessment and Determination of Some Heavy Metals in Commonly Consumed Traditional Herbal Preparations in Northeast Ethiopia

Background. Most traditional medicines were prepared from plant origins. These plants could be contaminated by heavy metals, pesticides, and/or toxins. Therefore, the aim of the present study was to determine the level of heavy metals such as lead (Pb), cadmium (Cd), chromium (Cr), and copper (Cu) in frequently used traditional herbal preparations sold in Northeast Ethiopia and to estimate their health risks associated with their daily intake. Methods. A total of 6 traditional herbal preparations were randomly collected from local herbal shops of Dessie and Kombolcha town, Northeast Ethiopia. The samples were prepared for analysis by wet digestion method using nitric acid and hydrochloric acid treatment. The accuracy of the method was analyzed by the spike recovery test. Determination of Pb, Cd, Cr, and Cu by microwave plasma atomic emission spectroscopy was made in herbal preparations traditionally used in Dessie and Kombolcha town, Northeast Ethiopia. By calculating estimated daily intake (EDI), hazard quotients (HQ), and Hazard Index (HI) of metals, the health risk associated with the consumption of the analyzed herbal preparations was also evaluated. Results. The levels of heavy metals were in the range of 3.0–3.92 mg/kg for Pb, 5.35–10.7 mg/kg for Cr, and 0.815–12.3 mg/kg for Cu. However, cadmium was not detected in any of the traditional herbal preparations. This study revealed that the level of Pb and Cu in all analyzed samples was within the WHO maximum permissible limit of 10 mg/kg and 40 mg/kg, respectively. The level of Cr in all traditional herbal preparations was beyond the WHO maximum permissible limit (2 mg/kg). From the health point of view, the HQ value of Cr for KD-03 and KD-04 is greater than 1, suggesting potential health risk. Furthermore, the HI value had revealed that the consumption of KD-02, KD-03, and KD-04 samples had the potential of posing health risks to consumers over long-term consumption of herbal preparations. Conclusion. This study showed that most of the metal concentration levels in the herbal products were within the WHO maximum permissible limits. However, all samples had Cr levels above the WHO maximum permissible limit. Based on the results of this study, there would be a noncarcinogenic health risk to the consumer associated with the consumption of some herbal preparations marketed in Northeast Ethiopia.

ARSENIC POLLUTION AND REMEDIAL MEASURES IN WEST BENGAL: AN OVERVIEW

During the past twenty years, Arsenic (As) contamination via groundwater has become a significant issue worldwide and is now a serious concern within the Indo-Bangladesh Gangetic delta. Arsenic enters physical body through contaminated groundwater consumed as beverage. Food safety in this region is facing severe consequences as bio-accumulation of Arsenic is happening through food crops irrigated with As-contaminated water. Chronic exposure to Arsenic may cause not only cancerous and non-cancer health effects. Reports suggest that about 20% population in West Bengal is very affected. Various techniques are being introduced to supply arsenic-free beverage at a reasonable cost. But a rigorous change in habit and state of mind for procuring safe beverage in those surviving in As-contaminated zones is that the most essential step towards curbing the fatal consequences of arsenic exposure. Harvesting rain water and utilization of proper purification techniques are often considered a possible alternative of safe beverage. Arsenic in groundwater above the WHO maximum permissible limit of 0.01 mg l−1 has been found in six districts of West Bengal covering a neighborhood of 34 000 km2 with a population of 30 million. at the present, 37 administrative blocks by the side of the River Ganga and adjoining areas are affected. Areas suffering from arsenic contamination in groundwater are all located within the upper delta plain, and are mostly within the abandoned meander belt. Quite 8,00,000 people from 312 villages/wards are affected with arsenic contaminated beverage and amongst them a minimum of 175 000 people show arsenical skin lesions. Thousands of tube-well waters in these six districts are analyzed for arsenic species. Hair, nails, scales, urine, liver tissue analyses show elevated concentrations of arsenic in people drinking arsenic-contaminated water for an extended period. The source of the arsenic is geological. Bore-hole sediment analyses show high arsenic concentrations in just few soil layers which is found to be related to iron-pyrites. Various social problems arise thanks to arsenical skin lesions in these districts. Poor socio-economic conditions, malnutrition, illiteracy, food habits and intake of arsenic-contaminated water for several years have aggravated the arsenic toxicity. altogether these districts, major water demands are met from groundwater and therefore the geochemical reaction, caused by high withdrawal of water could also be the explanation for arsenic leaching from the source. If alternative water resources aren't utilised, an honest percentage of the 30 million people of those six districts may suffer from arsenic toxicity within the near future.

Investigation on the quality of water from Jabi Lake in Abuja, Nigeria

Surface water may constitute public health issues if the water is contaminated. Consequent upon this assertion, the physicochemical parameters and tr ace metal concentration of Jabi Lake surface water were analysed and compared with WHO standards. Sixteen water samples were taken for analysis from Jabi Lake within Abuja in Nigeria. Official Methods of Analysis of the Association of Official Analytical Chemists (AOAC) were adopted in the analysis of the physicochemical parameters while heavy metals ions determination was performed using Atomic Absorption Spectrophotometer. The results obtained revealed marked differences in the levels of some physicochemical properties and trace metal ion concentration in the surface water samples when compared with WHO standards. Though most physicochemical parameters were within acceptable and safe limits, but with nitrate having higher concentrations. The concentrations of manganese, iron, cobalt, lead and chromium were well above the WHO maximum permissible limits for surface water. The pollution index of manganese, iron, cobalt, lead and chromium were above unity (1.0), indicating very high level of pollution. The results of the physicochemical and trace metal analysis when compared with WHO suggest that the water samples from Jabi Lake was not suitable for drinking while the concentrations of the metal ions were found decreasing in this order; Pb ˃Fe˃Cr˃Mn˃Co˃Zn.

Assessment of Heavy Metal Concentration in Fruit Samples from Three Major Markets during the Wet Season in Enugu State

The effect of seasonal changes on heavy metals concentration in three commonly edible fruits in Enugu State was analyzed. Banana, pineapple and watermelon samples were collected during three rainy season months (June, July and August) from three markets in the three districts of Enugu state (Enugu North, Enugu West and Enugu East). Heavy metals evaluated during the study include lead, cadmium, cobalt, nickel, zinc and copper. Metals in the samples were quantified using atomic absorption spectrophotometry (AAS) at specific wave lengths and values reported in mg/kg. The result of the study showed the maximum and minimum values of heavy metals observed in all the samples were; 0.28 – 0.03 mg/kg, 0.22 – 0.01 mg/kg, 0.13 – 0.01 mg/kg, 0.64 – 0.33 mg/kg, 0.69 – 0.01 mg/kg and 13.88 – 1.42 mg/kg for lead, cadmium, nickel, cobalt, copper and zinc respectively. The quantity of metals in all the samples, on average, reduces as the rainy season month progresses. The order of heavy metal concentrations in the fruit samples from the markets were in the following decreasing order; Nsukka market&gt; Ogbete market&gt; Ezeagu market. Banana fruit showed the highest concentration of heavy metals while watermelon showed the least heavy metal concentration. Values obtained were compared to WHO maximum permissible limit for each metal. Environmental pollution should be prevented in market areas to avoid food poisoning from consumption of contaminated food.

Assessment of Zinc, Lead, Chromium, and Cobalt in Commonly Consumed Herbal Medicines in Sindh, Pakistan.

Herbal medicines are widely consumed by the people of Pakistan for the treatment of various diseases. In the current study, quantitative assessment of four heavy metals namely zinc, lead, chromium, and cobalt was carried out in forty commonly consumed herbal medicines purchased from the markets of Khairpur and Sukkur, Pakistan. The conventional wet acid digestion method was used for the dissolution of samples and the concentration of heavy metals was determined by using flame atomic absorption spectrometry. Varied concentrations of metals were observed in different herbal medicines. The levels of Zn, Pb, Cr, and Co were in the range of 7.05-87.5 ppm, 5.62-44.9 ppm, 3.16-14.1 ppm, and 5.69-9.88 ppm, respectively. The findings of our study were compared with the WHO maximum permissible limits of these metals and it was observed that most of the analyzed samples exceeded the permissible levels. Keeping in view the levels of these metals in the selected herbal medicines, the prolonged intake of these drugs might be hazardous for human beings.

Heavy Metals Concentration in Mango (Mangifera indica L.) Grown around Some Gold Mining Areas of Zamfara State, Nigeria

Aims: This study was aimed at determining the concentration of heavy metals (Pb, Cd, Fe and Au) in mango plant parts (roots, stem barks, leaves and fruits) from two gold mining areas (Maraba and Duke) and the control (Kadauri) in Zamfara State, Nigeria for establishment of a baseline data for these metals and determining the suitability of the mango fruit for consumption.&#x0D; Study Design: Analytical study design was applied in a stratified manner for the research.&#x0D; Place and Duration of Study: The study was carried out in the environmental technology laboratory, National Research Institute for Chemical Technology (NARICT), Zaria, Nigeria between March and August 2019.&#x0D; Methodology: A cumulative total of 96 samples of plant parts (roots, stem barks, leaves and fruits) were collected and analysed for Lead, Cadmium, Iron and Gold using Atomic Absorption Spectrophotometer (AAS) after digestion with a mixture of 20 ml HNO3 and 8 ml HClO4.&#x0D; Results: The results obtained for the mean metal concentrations were; most abundant, Pb (62.07 ± 54.09 mg/kg) in mango roots from Duke and the least abundant, Cd (0.52 ± 0.44 mg/kg) in fruits from Kadauri. All the metals had very high (&gt; 0.5) translocation factors indicating fast movement from the roots to the shoots while the mean values of these metals in the fruits were found to be above the WHO and FAO maximum permissible limits which shows high level of contamination as a result of gold mining activities. Metals generally occurred in the order: Pb&gt;Fe&gt; Au &gt; Cd and they differed across sampling stations with the mining areas having significantly (P&lt;0.05) higher values than the control.&#x0D; Conclusion: Heavy metals concentration in mango plant was found to be generally higher than the permissible limits hence the fruits are considered unsuitable for human consumption.

English

The impact of gold mining on mango (Mangifera indica L.) grown in the vicinity of gold mining sites in Zamfara State, Nigeria have been assessed over the dry and wet seasons. Samples of mango plant parts were collected from 3 impacted sites and a control site monthly between March and August 2014, and analysed for selected heavy metals using Atomic Absorption Spectrophotometer. The results obtained indicate that Pb was the most abundant heavy metal in the mango roots (95.17 &plusmn; 68.49 mg/kg), stems (87.89 &plusmn; 64.11 mg/kg) and leaves (67.11 &plusmn; 57.11 mg/kg) found in Kwali and the least abundant metal was Ni (0.30 &plusmn; 0.44 mg/kg) in Kadauri (control site). The mean values of these metals were found to be above the WHO (1996) and Nigerian FMEnv maximum permissible limits indicating high level of contamination from gold mining activities. The abundances of the metals followed an unsequential pattern in the order Pb &gt; Fe &gt; Au &gt; Al, depending on the location, and differed significantly (P&lt;0.05) across sampling stations. Remarkably higher values of the contaminants were observed in the dry than the wet season.&nbsp; The sequence of heavy metal accumulation in the mango plants were Roots &gt; Stems &gt; Leaves &gt; Fruits which revealed that the roots bio-accumulated the heavy metals more than the fruits. Bio-accumulation factor (BAF) values determined varied with specific heavy metals, location and the season. Most BAF values were higher than 1 indicating that Mangifera indica is a hyperaccumulator and could be used as bioindicator for pollution studies. Key words: Heavy metals, Mangifera indica, BAF, gold mining, Nigeria. &nbsp