World Health Organization Permissible Limits Research Articles

Evaluation of the phytoremediation potential of selected hydrophytes grown in wastewater. A case study in Sheikhupura, Pakistan

Water pollution is a major environmental issue and human health risk worldwide. With rapid industrialization and economic growth, water bodies are contaminated at large scale. In the current study the concentration of four heavy metals (HMs) cadmium (Cd), copper (Cu), nickel (Ni), and manganese (Mn) was measured in water, sediment, and hydrophytes (Eichhornia Crassipes, Pistia stratiotes and Lemna minor) samples collected from wastewater stream in Sheikhupura, Punjab, Pakistan. The results revealed that the concentrations of Cd (0.23 mg L-1), Cu (5.00 mg L-1), Mn (6.00 mg L-1), and Ni (3.00 mg L-1) in water samples were above the permissible limits (APL) set by the World Health Organization (WHO). However, the concentration of Cd, Cu, Mn, and Ni in sediment samples was found to be below the maximum permissible limits (BMPL) set by WHO. The WHO permissible limits for Cd, Cu, Mn, and Ni in water is 0.01, 0.02, 0.20, and 1.40 mg L-1 respectively while in sediments is 3.00, 100, 2000, and 50 mg kg-1 respectively. In addition, Mn concentration was highest among all the tested hydrophytes, water, and sediment samples. HMs contents were higher in hydrophytes as compared to water and sediment samples. In addition, all three hydrophytes were found to absorb HMs from wastewater with bioaccumulation factor ranging from 2.52 to 216. Current data revealed that Pistia stratiotes have greater potential to absorb HMs from water as compared to Eichhornia Crassipes, and Lemna minor

Effect of waste dumpsite on the surface and groundwater supplies using water quality index in Afikpo south local government area, Ebonyi state

The research examined the effect of waste dumpsite on the surface and groundwater supplies using water quality index (WQI) in Afikpo South Local Government Area of Ebonyi State. Fifteen samples were drawn from fifteen locations. The samples were analyzed using standard methods. The results of the analyses were compared with the World Health Organization (WHO) drinking water standard. The WQI of the water samples were calculated and compared with the classification of water quality status. The results showed that the pH of the water samples ranged 4.6±0.047 – 6.70±0.090, EC 7.26±1.63 – 2450±4.32, Turbidity 0.50±0.082 – 2.00±0.094, TDS 23.10±0.047 - 1830±17.00, Alkalinity 45±0.47 - 2080±4.71, Total Hardness 4±0.47 – 170±0.94, DO 5.07±0.012 – 7.72±0.016, BOD 0.4±0.047 – 12.8±0.082, NO3 - 1.14±0.009 – 32.69±0.047 and 0.09±0.00 – 15.6±0.028. The results showed that the pH, Turbidity, Total Hardness, NO3 - were all below the WHO drinking water standard. All the locations of the water samples showed some levels of acidity. Apart from location MB that recorded high levels of TDS and Alkalinity every other location was below the WHO permissible limit of drinking water standard. The results of the analysis also revealed that the WQI value of the water was 57.92 and this was below the critical value of 100. From the findings, all the water samples need to be treated with alkali to reduce the low pH while the water samples generally need to be given comprehensive treatment before usage.

Techno-economic feasibility and life cycle assessment analysis for a developed novel biosorbent-based arsenic bio-filter system.

Significant aquifers around the world is contaminated by arsenic (As), that is regarded as a serious inorganic pollution. In this study, a biosorbent-based bio-filter column has been developed using two different plant biomasses (Colocasia esculenta stems and Artocarpus heterophyllus seeds) to remove total As from the aqueous system. Due to its natural origin, affordability, adaptability, removal effectiveness, and possibility for integration with existing systems, the biosorbent-based bio-filter column presents an alluring and promising method. It offers a practical and eco-friendly way to lessen the damaging impacts of heavy metal contamination on ecosystems and public health. In this system, As (III) is oxidized to As (V) using chlorine as an oxidant, after this post-oxidized As-contaminated water is passed through the bio-filter column to receive As-free water (or below World Health Organization permissible limit for As in drinking water). Optimization of inlet flow rate, interference of co-existing anions and cations, and life cycle of the column were studied. The maximum removal percent of As was identified to be 500µgL-1 of initial concentration at a flow rate of 1.5 L h-1. Furthermore, the specifications of the biosorbent material was studied using elemental analysis and Zeta potential. The particle size distribution, morphological structures, and chemical composition before and after binding with As were studied using dynamic light scattering (DLS), scanning electron microscope-energy dispersive X-Ray spectroscopy (SEM-EDX), and fourier's transform infrared spectroscopy (FTIR) analysis, respectively. SuperPro 10 software was used to analyze the techno-economic viability of the complete unit and determine its ideal demand and potential. Life cycle assessment was studied to interpret the environmental impacts associated alongside the process system. Therefore, this bio-filtration system could have a potential application in rural, urban, and industrial sectors.

Analysis of the Concentration of Heavy Metals in Khat Grown in Meru County and the Assessment of Their Associated Health Risks

Contamination of farm produce by toxic heavy metals has become a serious global health concern. These metals can bioaccumulate in plant tissues and are precursors for major public health problems such as cancer and neural impairment. Khat (Catha edulis) also referred to as miraa has the potential to sequester and accumulate both micronutrients and potentially toxic heavy metals in its consumable parts—tender leaves and soft barks of young shoots which are known to possess psychoactive properties when consumed. Therefore, the motivation behind this contribution is to determine the levels of six heavy metals, namely, cadmium (Cd), copper (Cu), chromium (Cr), lead (Pb), iron (Fe), and nickel (Ni) in consumable Meru khat samples, compare these levels with the permissible limits of World Health Organization (WHO) in order to predict associated health risks, and to estimate the noncarcinogenic risks of these metals by total health quotient (THQ) and health index (HI) on khat consumers. 1.0 g of dry ground khat samples was digested in 0.05 M HCl and allowed to stand for 5 hours before being analyzed for heavy metals using inductively coupled plasma atomic emission spectroscopy (ICP-AES). The mean heavy metal concentrations (mg/kg) in dry khat samples of six toxic heavy metals were Cd (7.81 ± 1.56), Cr (15.98 ± 2.22), Cu (15.81 ± 2.84), Fe (97.35 ± 32.67), Ni (0.37 ± 0.02), and Pb (32.36 ± 9.95). Based on the results, the mean levels of Pb, Cd, and Cr exceeded WHO permissible limits. In addition, the Pb and Cd THQ values and the HI of the six heavy metals investigated in the khat samples exceeded the threshold value of 1.0. Furthermore, the THQ and HI values showed that Pb and Cd were potentially the major contributors to noncarcinogenic risks on regular khat consumers. This is a matter of concern on the excessive consumption of Meru khat-based products, which over time may cause a toxicological response. Based on the findings of this study, the use of agrochemicals should significantly be minimized in khat farming. Accordingly, the Meru khat farmers should be sensitized on alternative farming practices that do not potentially cause heavy metal contamination in khat.

Analyses of the Elemental Content of three Brands of Natron in Four Local Government Areas in Kebbi State

Natron is the second most consumed salt in Nigeria. It is used as a food additive to cook beans, maize, and other palatable foods. Several studies have investigated the elemental content in this salt in Nigeria. However, there is paucity of information on the elemental content of this widely consumed salt in Kebbi State. Thus, this study is focused on the analyses of elemental content in Natron in sold in four Local Government Areas (LGAs) of Kebbi State. Three brands of Natron were collected from markets in Birnin Kebbi, Jega, Kalgo and Bunza local governments. Atomic Absorption Spectroscopy (AAS) was used to analyse the elemental content. Furthermore, the elemental content values were collated for the samples of the different brands of Natron. The sodium content of the Kanwa Jarirai brand in Jega had the lowest sodium content of while the Balma brand in Bunza had the highest sodium content of . All three Natron brands investigated in the four LGAs exceeded the World Health Organization (WHO) permissible limit for potassium, iron and, manganese levels. All the brands of Natron did not satisfy the adult daily calcium intake except for the Kanwa Jarirai from Jega with . Moreso, all the three brands in the selected four LGAs satisfied the sodium permissible WHO limits. The iron, manganese, and potassium WHO permissible limits were not met. In addition, the Natron from the four LGAs did not satisfy the adult daily intake of calcium except the Kanwa Jarirai from Jega. Consumers will need to be cautious of the usage of the analysed Natrons as they contained high levels of sodium which might not be beneficial to cardiovascular health.

Assessment of Heavy Metal Contents in Some Common Spices Available in the Local Market of North Shewa Zone, Oromia Regional State, Ethiopia.

The objective of this study was to determine the contents of heavy metals in some common spices commercially available in the North Shewa Zone, Oromia region, Ethiopia. Korarima seed (Aframomum corrorima), ginger rhizome (Zingiber officinale), red pepper fruit (Capsicum annum), and turmeric rhizome (Curcuma longa) samples were randomly collected from the Fiche open market. These spice samples were digested using a mixture of 3mL of HNO3 (69-72%) and 1mL of HClO4 (70%), where organic components are assumed to decompose into gaseous forms while other heavy metal elements are left in the solution. The contents of heavy metals (Fe, Zn, Cu, Cr, Mn, Ni, Cd, and Pb) in the spices were determined by inductively coupled plasma‒optical emission spectrometry (ICP‒OES). The results obtained showed that the concentrations of heavy metal in the korarima, red pepper, ginger, and turmeric samples in milligrammes per kilogramme of dry weight were in the range of Fe (38.7-98.9), Mn (10.5-257), Zn (7.30-29.2), Cu (1.70-6.50), Cr (5.40-9.70), Cd (1.50-2.90), Pb (14.5-28.4), and Ni (3.90-6.70). The heavy metal contents in korarima, red pepper, ginger, and turmeric samples were compared with the maximum values given by the World Health Organization (WHO). Accordingly, the Fe, Zn, Cu, Cr, Mn, and Ni values in the spice samples were found to be lower than the maximum limit of the WHO, while the levels of Pb and Cd in four spice samples and Mn (only in ginger) were higher than the WHO permissible limit. Thisstudyshowsthatthe consumption of korarima, red pepper, ginger, and turmeric may pose a serious health threat to consumers due to the high content of lead, cadmium, and manganese (only in ginger) in spices. Therefore, it is suggested that further study be conducted on spice samples based on the origin of cultivation to determine which hotspot is responsible for high levels of contamination of lead, cadmium, and manganese to protect consumers.

Assessment of some bottled natural mineral waters and spring waters in Algeria using multivariate statistical analysis, hydrogeochemical approaches and water quality index (WQI)

ABSTRACT In Algeria, the consumption of mineral waters has grown enormously, indicating that these waters have safe quality for drinking use. The objectives of the present study are to evaluate the physicochemical characteristics of 43 bottled mineral waters and to identify the main hydrogeochemical processes governing water chemistry using a combination of geochemical techniques and multivariate statistical approaches. The results revealed that the abundance order of cations and anions (mg/L) are Ca2+> Na+> Mg2+> K+, HCO3 −> SO4 2−> Cl−> NO3 −. In addition, the comparison between the obtained results and World Health Organization (WHO) standards showed that the analysed physicochemical parameters (pH, Na+, Cl−, SO4 2−, NO3 −) are within the acceptable limits of the World Health Organization (WHO) for drinking except TDS, Ca 2+, Mg2+, K+, HCO3 −, which exceed the WHO permissible limits in few water samples. Hydrogeochemical types in the study area were Ca2+-HCO3 −, Ca2+-Mg2+-HCO3 −, Ca-Mg2+-SO4 2—Cl-, Na+-HCO3 − and Na+-Cl−types, with a low mineral and intermediate mineral contents based on Van der Aa’s classification. The Gibbs plot specifies that almost all samples (93%) fall in water–rock interaction dominance. The major hydrogeochemical processes acting are dissolution of carbonate minerals, ion-exchange mechanisms and silicate weathering. Principal component analysis (PCA) was applied to hydrochemical data of mineral water samples. The results suggest that hydrochemistry in the region is affected not only by geogenic processes but also is impacted by anthropogenic activities. The comparative evaluation of the different water quality indices (WQI) shows that there is a difference between indices values for the same water sample, which may be attributed to the weighting methods, aggregation methods, and the limits of classes used in the calculation of each index. The results from this study can provide the basis for local decision-makers to develop suitable water management strategies and protection against any pollution risk.

Perspective of heavy metal potential risk in wetland soil and fish for amplified waste management around Lake Victoria, Uganda

Ssanyu GA, Kiwanuka M, Lunkuse I, Okumu D, Mbeiza NM. 2023. Perspective of heavy metal potential risk in wetlands soil and fish for amplified waste management around Lake Victoria, Uganda. Lake Reserv Manage. X:XXX–XXX. Increasing unsustainable agricultural and land management activities reduce the effectiveness of wetlands in absorbing heavy metals. This leads to high and detectable heavy metal levels in wetland soil and fish, respectively. This study assessed the content of heavy metals, particularly cadmium (Cd), chromium (Cr), cobalt (Co), lead (Pb), and nickel (Ni), in the water, soils, and commercial wetland fishes (Protopterus aethiopicus and Clarias galiepinus) from Lake Victoria wetlands with different land uses. Heavy metal analysis was done using inductively coupled plasma–optical emission spectrometry. Mean Cd and Pb levels were below the World Health Organization (WHO) permissible limits in all the wetlands’ water samples. Wetlands associated with urban or industrial development presented higher levels of Pb than other wetlands. Wairaka wetland, associated with commercial agriculture, presented a significantly higher mean concentration of Cr (191.2 mg/kg) in the soil than other wetlands. Cr and Ni contents were high in all fish muscle samples, while Cd and Pb contents in fish muscles were below WHO permissible limits, except for Clarias fish from 2 urban/industrial and one commercial agriculture affected wetlands, which had higher Pb than in other fish muscle tissues. The hazard index values of both fish species were greater than one from urban/industrial and commercial agriculture associated wetlands, implying that fish consumers would encounter noncarcinogenic health risks. More efforts are needed to strengthen Lake Victoria industrial and municipal waste management strategies to reduce the potential heavy metal risk in wetland soil and fish.

Assessment of the Quality of Newly Constructed Hand-Dug Well Usetd for Drinking and Their Treatment System at Kenema Town, Kenema District, Eastern, Sierra Leone

The tremendous increase in the human population increase the stress on both surface and groundwater and it is believed that at the beginning of human civilization itself, groundwater was the most trusted form of drinking water because of the filtering effect of the aquifer however, in the present world drinking water directly from the source without proper treatment is very tough and risky for the health. Kenema District is a district in the Eastern Province of Sierra Leone, its capital and largest city is Kenema City, which is the third most populous city in Sierra Leone, after Freetown and Bo Both the physical and chemical Parameters investigated are within the WHO acceptable limits, except one of bioteriological parameters (non- faecal coliform). Tables 1, 3, and 4 show high statistical mean values for the Non-Faecal Coliform bacteria in the hand dug wells. Diema Hand Dug Well (12.00 cfu/100ml), Ansarul Hand Dug Well (11.67 cfu/100ml) and the combined statistical mean value (10.78cfu/100ml) of the Non-Faecal Coliform bacteria and all the values fell out of World Health Organization (WHO) permissible limit. However, Islamic Hand Dug Well has a statistical mean value of 8.67 cfu/100ml of Non-Faecal Coliform Value which is within the WHO permissible limit (<10cfu/100ml). The combined statistical mean value for Diema, Islamic, and Ansarul hand dug well for the following physiochemical parameters (pH 7.14, Turbidity 2.46NTU, Conductivity 196.56, TDS 100.11mg, Ammonia 0.02mg/l, Nitrite 0.02mg/l, Nitrate 0.06mg/l, Phosphate 6.15mg/l, Cadmium 0.00gm/l, Copper 0.02mg/l, Iron 0.03mg/l and Zinc 2.67mg/l) are all within the World Health Organization permissible limits (Table 4). Non-faecal coliforms were discovered in all of the wells and boreholes examined and analyzed in a similar investigation to identify the bacteriological pollution of groundwater sources.

Potentially toxic element contamination and risk assessment of borehole water within a landfill in the Nnewi metropolis

Borehole water has been used as a vital source of water for many communities. The pollution of these boreholes by potentially toxic elements using unlined solid waste dumpsites has posed a significant risk to the populace living around the dumpsite. This study investigates the environmental impact of potentially toxic elements on borehole water within the vicinity of an unlined dumpsite in the Nnewi metropolis. The upstream and downstream samples (16 each) were collected in wet and dry seasons. The potentially toxic elements analysis wasperformed using the methods of the American Public Health Association (APHA) under the required conditions. The quality of the boreholes was assessed using the World Health Organisation (WHO) acceptable limits for drinking water. The risk assessment was estimated for carcinogenic and non-carcinogenic risks using ingestion and dermal routes. The results show that the borehole water wascontaminated with potentially toxic elements through leachate infiltration, which exceeded the WHO permissible limits for drinking water at both locations and seasons. The upstream borehole samples were more contaminated than the downstream samples for both seasons, due to their proximity to the pollution source. The hazard indices of the ingestion and dermal routes showed that the borehole water poses serious cancer and non-cancer health risks for both locations. The results revealed that children are more susceptible to cancer and non-carcinogenic health threats than adults for both locations and seasons. The pollution indices of borehole water for wet season (9.028 and 5.728) and dry season (7.107 and 5.328) for upstream and downstream samples respectively, were polluted and the pollution was higher in the wet season. The borehole water samples were unsuitable for drinking water and should be treated before use.

Health Risk Assessment of Heavy Metal Contamination of Groundwater Around Nnewi Industrial Area, Anambra State, Nigeria

The influence of water quality from boreholes situated around the Nnewi industrial area was evaluated by assessing the heavy metal concentrations and health risks associated with human exposure. Water samples were collected from 16 different boreholes around eight industries at a monthly interval from May – October 2019 and November 2019 – April 2020 to cover the rainy and dry seasons, respectively. Water samples were analyzed for copper (Cu), lead (Pb), iron (Fe), zinc (Zn), chromium (Cr), and arsenic (As) using atomic absorption spectrophotometer (AAS). The results were compared with the World Health Organization (WHO) standards. Data obtained for both seasons indicate Cu had a mean value of (0.268±0.136 mg/L), Pb (0.014±0.013 mg/L), Fe (0.119±0.133 mg/L), Zn (0.572±0.220 mg/L), Cr (0.051±0.011 mg/L), and As (0.013±0.001 mg/L) respectively. All the heavy metal concentrations of the sampled water were within their various WHO permissible limits except As, Cr and Pb. The pollution index of As, Cr and Pb were greater than 1, showing heavy contamination of the water. Carcinogenic risk assessment of water via ingestion and dermal route for Cr and As were above the recommended safe limit of 1×10^-6 which posed a cancer risk. The results show that borehole waters were contaminated with heavy metals in both seasons. It is, therefore, recommended that borehole water from the study areas should be treated before being used for various domestic purposes.

Immobilization of Heavy Metals in Contaminated Soil using Calcium Phosphate Amendment and Phosphate-solubilizing Fungi (Penicillium sp) in Benin City, Edo state, Nigeria

Soil is a limited resource that is continually contaminated by the presence of heavy metals as a result of human activities. This study used a combination of calcium phosphate amendment and phosphate-solubilizing fungi to immobilize heavy metals in polluted soil. Bovine bones were collected at an Abattoir Market in Aduwawa, Benin City, Nigeria with coordinates 6°22’6.24” N and 5°41’0.24” E and calcined to extract calcium-phosphate (hydroxyapatite), serial dilution and plating on Pikovskaya medium were utilized to obtain fungi extract from fertile soil. Prior to remediation, heavy metal analysis of polluted soil indicated high value of metal concentrations zinc 120.60mg/kg, chromium 22.67 mg/kg, cadmium 11.23 mg/kg, lead 18.43 mg/kg, iron 187.27 mg/kg and nickel 10.62 mg/kg above the World Health Organization permissible limit. There was a decrease in zinc and iron contents after the first week of treatment. The second week demonstrated a significant decrease in all metal concentrations; 27.53% for Zn, Cr 39.83%, Cd 46.13%, Pb 7.60%, Fe 46.26% and Ni 15.07% – indicating the treatment’s effectiveness.

Concentration and Comparison of Groundwater Quality in Kano Metropolis, Nigeria

The paper examined the concentrations of heavy metals and microbial parameters in groundwater and were compared to World Health Organisation (WHO)guidelines and National Standard for Drinking Water Quality standard. A total of 800 boreholes and wells water samples were purposefully and systematically collected in the metropolis and subjected to laboratory analysis where mean concentration values of Cadmium, Chromium, Zinc, Iron, Lead, Mercury, Arsenic, Copper, Manganese, Total Coliform count and Escherichia coli were determined in line with APHA 1998 standard procedures. The T- test statistical analysis, p&lt;0.05 results showed that there were high and low significant variations between the concentrations values of heavy metals with WHO and NSDWQ permissible limits especially during wet season while microbial parameters only showed high significant variations except Zinc, Mercury, and Arsenic recorded no significant differences. The study therefore drew inference that wastewater and geomorphic processes contribute significantly to groundwater contaminations in the metropolis and recommends public education and enlightenment, strong legislation, provision of standard water treatment plants, adoption sustainable environmental concepts, attitudinal change, good drainage system should strictly be adhered to in order to harness good drinkable water potentials.

Identification of Aquatic Macro-invertebrates and Determination of E. coli and Heavy Metals in Rawal Lake, Pakistan

Water is an important constituent of life’s support system. However, industrial growth, urbanization and anthropogenic activities have affected the quality of water bodies mostly in the world. The aim of the study was to assess the water quality of Rawal Lake, Pakistan, which is source of drinking water for the residents of Islamabad and Rawalpindi, using macro-invertebrates as pollution indicators, and through microbial and heavy metal analysis. For this purpose, macro-invertebrates and water samples were collected from Rawal Lake (Korang Nala Entrance), Rawal Lake (Centre) and from Rawal Lake (Spillway) points. The collected samples were preserved and transported to the Kinnaird College laboratory, where macro-invertebrates like caddisfly, water boatman, water bugs, gilled snails, mayflies etc. were identified with the help of identification guides and keys, while the presence of E. coli and heavy metals: Cadmium, Copper, Chromium, Cobalt, Nickel, Manganese and Zinc in the water samples was assessed. The results showed that pollution sensitive macro-invertebrates were mostly found in Rawal Lake (Centre), indicating that the water undergoes a self-cleaning process, whereas, water samples of Rawal Lake (Korang Nala Entrance), Rawal Lake (Spillway) had mostly pollution tolerant species, which signified that the water of these areas was moderately polluted. Simpsons’ Index of Diversity for Rawal Lake indicated a high level of diversity in the area (0.85). Microbial analysis indicated the presence of E. coli in all the three sampling points of the lake. The levels of Cadmium (Korang Nala 0.007 ppm, Spillway 0.014 ppm) were found toexceed the World Health Organization permissible limits (0.005 ppm), in the water samples, however, the concentration values of other metals were within the permissible limits. Thus, it was concluded that the water of Rawal Lake was considered fit for drinking and other purposes in residential and commercial areas after being processed through a treatment plant.

Physico-chemical analysis of Obizi River in Awka South Local Government Area of Anambra State, Nigeria for domestic purposes

Physico-chemical properties of obizi river in awka south local government area of anambra state were analyzed for its pollution level and determined if it will be fit for domestic purposes. It is significant for cooking, drinking, fishing, recreational and other uses. It flows via a channel that may be contaminated by industrial, agricultural, and other anthropogenic activities, limiting its normal uses for cooking, drinking, fishing, recreational and other uses. The parameters analyzed includes temperature (°C), pH, turbidity (NTUb), conductivity μs/cm, resistivity mg/l, chloride mg/l. Temperature(°C), pH, turbidity (NTUb) resistivity mg/l and conductivity μs/cm was measured in-situ using mercury thermometer with a range of 100C -350C, pH meter (HANNA H1991002), turbidimeter (Hl 88703, WAGTECH), conductivity and resistivity multi-meter (HI 991300, Hanna Instruments, Romania) and chloride was determined by titration. The results of the analysis were equivalence with world health organization (WHO) limit for domestic drinking water and other purposes. From the results obtained, it showed that all the parameters analyzed were above WHO permissible limit except resistivity and chloride which is within the world health organization (WHO) limit for domestic drinking water. As much, it is not recommended for human consumption and is recommended that the state government put in place a treatment plant which can be used to treat the obizi river water before being used by the community that depends solely on it for domestic purposes.

Bioavailability and health risk assessment of potentially toxic elements in salty water environment of Okposi, Southeastern Nigeria

This study is to determine some physicochemical parameters and potentially toxic elements (PTE) in water samples collected from a borehole, a stream and a lake in Okposi, Nigeria, for their quality status and the human health risk of exposure to the waters. The physico-chemical properties: pH, electrical conductivity (EC), salinity, nitrate and sulphate, were determined by standard methods, while the level of PTE contamination was analysed by Flame Atomic Absorption Spectroscopy (FAAS). The results show that the levels of physicochemical parameters in the water samples are within the World Health Organisation (WHO) permissible limit. The PTE concentrations (mg/L) in the samples are in the ranges of 0.12–0.35 (Cr); 0.06–0.19 (Cu); 0.24–2.45 (Fe); 0.0–0.06 (Mn); 0.00–0.75 (Pb); and 0.0–02 (Zn). The levels of Cr and Pb in all the samples, except Pb in the downstream water, are above the WHO permissible limits, indicating that the waters are contaminated and unsafe for drinking. PTE form complexes with anions in water at high EC and salinity which reduces availability of toxic metals to organisms. Therefore, toxicity of PTE in the samples is in decreasing order: Upstream > Downstream > Lake water > borehole water. Calculations of hazard quotients shows possible adverse effects on adults and children on dermal contact with the waters due to Cr. Children might get cancer due to Pb on ingestion of water from the studied borehole, the Lake and the Upstream waters. Statistical analysis suggests that the geology of the area influenced PTE contamination of the water bodies.Article highlightsEvaluation of the pollution status of the major water sources (borehole, lake, upstream and downstream) in the study area was conducted since the information will be useful for making decisions that will protect human health by the policy makers and the public.The samples from all the water bodies in the study area were contaminated by chromium. The borehole water samples were contaminated by Iron and Lead; the downstream samples were contaminated by Iron; while samples from the lake and the upstream were contaminated by Lead. They are contaminated because the concentrations of these metals in the water bodies were above the World Health Organisation’s permissible limit for those metals in drinking water. Human exposure to the level of these metals in the water bodies may lead to severe health problems.Based on the bioavailability studies of the metals and the physicochemical parameters of the major water bodies in the study area, the borehole water (ground water) is the safest (best) for drinking and domestic purposes, then, the lake water (safer), followed by the downstream water (safe), while the upstream water has the highest toxicity potential (not safe).

An analysis of drinking water quality parameters to achieve sustainable development goals in rural and urban areas of Besisahar, Lamjung, Nepal

AbstractNepal has a high annual rainfall, but it still faces numerous challenges in ensuring good water quality. A total of 20 water samples were collected from five springs, seven rivers, one borehole, and seven reservoir tanks. pH, electrical conductivity, total dissolved solids, turbidity, total hardness as CaCO3, and residual chlorine in the water samples were all found to be within the National Drinking Quality Standards (NDWQS) and World Health Organization (WHO) recommendations. The chemical oxygen demand (COD) was calculated in the range of 35.65–70.826 mg/L, where most of the water samples exceeded the WHO's threshold. The mean biological oxygen demand (BOD) value was 2.929 mg/L, which was below the WHO tolerance level. Moreover, the concentrations of zinc, copper, chromium, arsenic, cadmium, lead, chloride, fluoride, nitrate, nitrite, sulfate, and phosphate species studied here were lower than those of the NDWQS and WHO standards. It was found that most of the water samples crossed the threshold standard for Escherichia coli and total coliforms, respectively. The iron concentrations in BW8, PW9, and RVW10 were estimated at 0.321, 0.301, and 0.367 mg/L, manganese in BW8, RVW10, and PW9 at 0.191, 0.142, and 0.104 mg/L, and selenium in RVW10 and RVW14 at 0.041 mg/L, which exceeded the WHO permissible limit. In most samples, the contamination factor (CF) values of COD exceeded unity, and the pollution load index (PLI) was calculated at 1.3. In the CF analysis of Fe, Mn, and Se, it was found that some water samples were polluted and not suitable for drinking. Statistical analysis of water quality parameters revealed a significant correlation. Overall, the results suggest that governments and development agencies should enhance their involvement in water resources management to ensure sustainability.

Effects of landfill leachate on groundwater and its suitability for use

Landfill leachate is a noxious liquid with the potential to pollute groundwater resources following its horizontal and vertical mobilization from unsaturated to saturated zones. In this study, the characteristics of leachate from Roundhill landfill of South Africa were assayed using physicochemical analysis. Areal groundwater was sampled to assess the pollution capacity of leachate to the resource and the possibility of using it. Results showed that leachate had elevated levels of electrical conductivity, dissolved solids, cations and anions compared to the predefined standards by World Health Organization (WHO) and South African National Standards (SANS) for drinking water and its pH was 4.7. It was therefore not suitable for drinking and domestic use. In BH1, Ca2+, Mg2+, Fe and F− surpassed WHO permissible limits while Fe, F− and NO3− were above SANS standards for drinking and domestic water uses. In BH2, Fe levels were beyond both the SANS and WHO permissible levels. In BH3, Na+ and Fe were beyond both reference standards while Cl− surpassed SANS permissible limits. Pollution of groundwater was associated with the characteristics of disposed solid waste at the facility, which decomposed to generate leachate that infiltrated into the resource. Sodium adsorption ratio showed a mild sodicity problem while elevated levels of Ca2+ in BH1 and Mg2+ in BH1 and BH3 pointed to hardness of the water, which impedes irrigation suitability. Frequent and extensive monitoring of areal groundwater was recommended as the movement of leachate was established to be slow and inconsistent over time.

Variation of rain water quality with storage time for different coloured storage containers

It is very important to evaluate the quality of rain water collected and stored in cisterns and storage tanks. In this study, rainwater quality analysis was carried out on samples collected from an experimental set -up at the School of Engineering and Engineering Technology of the Federal University of Technology, Akure, Nigeria. The physio-chemical and bacteriological characteristics of rainwater collected and stored using four different coloured containers under outdoor and indoor conditions were analyzed and the results compared with World Health Organization (WHO) standard for potable water. The results of the physio-chemical analysis revealed that the colour, turbidity, total dissolved solids (TDS), phosphate, sulphate, iron and copper of all the rainwater samples fell within WHO acceptable standards for potable water. The pH of the harvested rainwater of the samples ranged from 5.34 – 6.73 mg/l for the indoor stored rainwater samples and 5.28 – 6.59 mg/l for the outdoor stored samples. The pH of the water samples did not fall with WHO permissible limit of 6.5 to 8.5. The Nitrate content of the water samples also did not fall within WHO permissible limit. Similarly, the total coliform count did not conform to WHO standard for potable water. Based on the results obtained from this study, it is recommended that harvested rainwater be treated to kill contaminating microorganisms and to reduce the health risks associated with its consumption.

Investigation of heavy metal levels of clams (Egeria radiata) sold in open markets in Port Harcourt and Yenagoa, Nigeria

Due to rapid urbanization, increase in coastal population, oil and gas exploration and other array of anthropogenic activities within the Niger Delta region of which Rivers and Bayelsa states are prominent amongst others, the region has been faced with coastal water pollution. There is need therefore, to evaluate the intensity of environmental contamination of the aquatic ecosystem in this region, thus this study was conducted to investigate the heavy metal levels of Clams (Egeria radiata) sold in open markets in Port Harcourt (Rivers State) and Yenagoa (Bayelsa State). Samples were collected from three markets in Port Harcourt (Mile 1, Rumuokoro and Mile 3), and three markets as well in Yenagoa (Opolo, Swali and Tombia) respectively. The samples were collected bi-weekly for 3 months and transported to the laboratory for analysis of heavy metals (Cr, Cd and Pb) levels using standard scientific method of analysis. The analysis was done in triplicates for each sample and data obtained were subjected to statistical analysis using excel spreadsheet and statistical package for social sciences (SPSS) version 21. The results revealed that samples collected from markets in Port Harcourt had higher concentrations of heavy metal than that of Yenagoa, though, the heavy metal levels were below World Health Organisation permissible limits, except for Cadmium (Cd) that ranged from 0.54±0.002 to 0.78±0.00 mg/kg in samples collected from Port Harcourt, against 0.5 mg/kg recommended by WHO. This could be attributed to oil and gas exploration, and discharges of industrial and domestic wastes bearing cadmium, and poses serious health risks. Therefore, routine monitoring and assessment of the aquatic ecosystem will be vital to forestall further contamination.