World Health Organization Limits Research Articles

Diagnosis of Crude Oil Impacted Soil in Eleme Local Government Area, Rivers State, Nigeria

This study assessed the potential effects of crude oil on soil quality in Eleme Local Government Area of Rivers State. Soil samples were collected from 10 geopolitical wards of the Eleme Local Government Area of Rivers State, Nigeria. The soil and water samples were subjected to physicochemical and microbial analyses to test for pH, heavy metal content (Cadmium, Iron, Lead, Copper, and Chromium), Total Petroleum Hydrocarbon (TPH), Benzene, Toluene, Ethylbenzene and Xylene (BTEX) contents and Total Viable Count (TVC). Parameters of the soil were determined and compared to the control site and the permissible World Health Organization (WHO) limits. The soil pH varied across location, ranging from 5.5-7. TPH varied in across the different communities studied, ranging from 1.275-4889.29 mg/kg, and exceeding the WHO limit of 10mg/kg in all polluted soils. The result for the heavy metals showed that the soil samples of the studied sites showed increases in all heavy metals, when compared to the control. Cd values ranged from 0.01 - 0.32 mg/kg; Fe from 1325.23 - 9364.76 mg/kg, Pb from 0.001 mg/kg to 0.93 mg/kg and Cr from 0.001 - 5.08 mg/kg, all with WHO limits. The result for the microbial showed increases in TVC content in polluted soil. Results indicate that crude oil spillage has led to significant contamination of soil in the study area which could affect soil fertility.

ASSESSMENT OF HEAVY METAL CONTAMINATION IN FISH AND WATER SAMPLES FROM BABBAN WUYA MADACHI RIVER: IMPLICATIONS FOR HUMAN HEALTH AND ENVIRONMENTAL SUSTAINABILITY

This manuscript investigates the presence and concentration of heavy metals, namely zinc (Zn), copper (Cu), lead (Pb), and cadmium (Cd), in water and two commonly consumed fish species (Tilapia and Catfish) from the Babban Wuya Madachi River. Heavy metal contamination poses significant risks to both human health and environmental sustainability. The study employs Atomic Absorption Spectroscopy (AAS) to analyze heavy metal concentrations in water and fish samples collected from ten different points along the river. The mean concentration of Zn, Cu, Pb, and Cd in the Tilapia fish, Catfish and water are 50.85 ± 0.22, 2.84 ± 0.27, 7.89 ± 0.78, 0.80 ± 0.02 mg/kg; 33.87 ± 1.08, 1.49 ± 0.10, 3.74 ± 0.42, 0.33 ± 0.01mg/kg; and 0.07 ± 0.00, 0.09 ± 0.00, 0.05 ± 0.02, BDL mg/L respectively. Results indicate that water concentrations generally fall below World Health Organization (WHO) standards, while the concentrations of certain heavy metals in fish samples exceed WHO limits, notably Zn, Pb, and Cd. Moreover, concentration of Cu in fish samples is within the standard WHO limit of 2.25 mg/kg and in water its concentration is below the standard limit of 2mg/L. It has been reported that, heavy metals such as Zinc, Cd and Pb has a unique behavior that once absorbed by man it retained in the body system for long and accumulate to cause kidney problems and born demineralization through direct bone damage or indirect through renal dysfunction. The findings underscore the necessity of continued monitoring...

EVALUATION OF HEAVY METALS' CONCENTRATION AND PHYSICOCHEMICAL PARAMETERS OF GROUNDWATER WITHIN JOS METROPOLIS OF PLATEAU STATE, NIGERIA

This paper studied the quality of drinking water from borehole sources in Jos and its environs. The level of heavy metal concentrations and some physicochemical parameters were determined using standard methods. The result of heavy metal concentrations analyzed within the ten (10) sampling points shows that JS1 sampling point had a significantly high (p<0.05) concentration of copper (0.0064 mg/L) and lowest in JS1 sampling point (0.001 mg/L). Chromium had a significantly high (p<0.05) concentration in JS10 sampling point (0.718 mg/L) and lowest in JS1 (0.153 mg/L). Manganese had significantly high (p<0.05) concentration in JS4 sampling point (0.198 mg/L) and lowest in (JS6 0.020 mg/L). Iron was significantly high (p<0.05) in JS4 sampling point with the concentration of 1.388 mg/L and lowest value of 0.020 mg/L in JS5. Zinc had a significantly high (p<0.05) in JS4 sampling point with the concentration of 0.085 mg/L. Lead had significantly high (p<0.05) in JS8 sampling point with a concentration of 0.005 mg/L. Cadmium and nickel were not detected in all ten (10) sampling points. The electrical conductivity and pH and were found to be in the range of (0.000 - 350 µSv/cm) and (4.81 – 6.70), respectively. This research findings suggest that continued water quality monitoring should be carried out to check the concentration levels of copper, zinc, manganese, cadmium, nickel, lead and physicochemical parameters electrical conductivity and pH in those ten (10) sampling points to prevent them from been above the limit of World Health Organization (WHO) permissible limit and also creating...

Generation of PM10 Map with Sentinel-2 Satellite Images: The Case of Çankırı Province

Air pollution, which is characterized as a global environmental problem, negatively affects life in Turkey as a result of the increase in the amount of energy needed and uncontrolled construction. In order to minimize the health impacts of air pollution, air quality should be monitored regularly and necessary steps should be taken to improve it. With the innovations in satellite technologies, the air quality of large areas can be monitored with the help of satellite images and effective solutions can be produced in many areas such as the detection of air pollutant parameters and the creation of thematic maps. The main objective of the research is to investigate the relationship between in-situ measured PM10 parameters and Sentinel-2 satellite data and to map PM10 based on this relationship. In this context, PM10 parameters measured in the field on two different dates and Sentinel-2 satellite images dated 22.11.2021 and 16.04.2022 were used as data sources. The relationship between the data used was established by multiple regression analysis. The coefficients obtained from the analysis results were applied to the relevant bands and thematic maps were created using satellite images. The correlation coefficients of 0.80 and 0.79 calculated by regression analyses indicate that sufficient accuracy was achieved in the research. The results of the study show that satellite imagery provides accurate data for PM10 estimate and that pollution exceeds World Health Organization limits in the road transportation network and industrial areas.

Long-term exposure to ambient air pollution and risk of microvascular complications among patients with type 2 diabetes: a prospective study.

Patients with type 2 diabetes (T2D) may disproportionately suffer the adverse cardiovascular effects of air pollution, but relevant evidence on microvascular outcome is lacking. We aimed to examine the association between air pollution exposure and the risk of microvascular complications among patients with T2D. This prospective study included 17 995 participants with T2D who were free of macro- and micro-vascular complications at baseline from the UK Biobank. Annual average concentrations of particulate matter (PM) with diameters <2.5 μm (PM2.5), <10 μm (PM10), nitrogen dioxide (NO2) and nitrogen oxides (NOx) were assessed using land use regression models. Cox proportional hazards regression was used to estimate the associations of air pollution exposure with incident diabetic microvascular complications. The joint effects of the air pollutant mixture were examined using quantile-based g-computation in a survival setting. In single-pollutant models, the adjusted hazard ratios (95% confidence intervals) for composite diabetic microvascular complications per interquartile range increase in PM2.5, PM10, NO2 and NOx were 1.09 (1.04-1.14), 1.06 (1.01-1.11), 1.07 (1.02-1.12) and 1.04 (1.00-1.08), respectively. Similar significant results were found for diabetic nephropathy and diabetic neuropathy, but not for diabetic retinopathy. The associations of certain air pollutants with composite microvascular complications and diabetic nephropathy were present even at concentrations below the World Health Organization limit values. Multi-pollutant analyses demonstrated that PM2.5 contributed most to the elevated risk associated with the air pollutant mixture. In addition, we found no interactions between air pollution and metabolic risk factor control on the risk of diabetic microvascular complications. Long-term individual and joint exposure to PM2.5, PM10, NO2 and NOx, even at low levels, was associated with an increased risk of diabetic microvascular complications, with PM2.5 potentially being the main contributor.

Spatial Trends and Distribution Patterns of Toxic Heavy Metal Contamination in an Urbanized Watershed

Rapid urban growth in developing nations exacerbates pressures on water resources through increased pollution loading if management practices cannot adapt efficiently. This study evaluated industrial effluent impacts on river systems in Nigeria contaminated by discharge from beverage, oil and biscuit manufacturing plants. Physicochemical parameters and heavy metal concentrations were monitored at sites upstream and downstream from waste outfalls during wet and dry seasons. Results demonstrated exceedances of national water quality standards for indicators of organic pollution like biochemical oxygen demand and chemical oxygen demand. Notably, highly toxic heavy metals exceeded World Health Organization limits by over 100 times, posing serious public health concerns through various exposure pathways. Seasonal variations reflected changes in pollution inputs. Spatial trends showed metal levels decreasing with distance, though remaining well above safe levels 100m downstream. A predictive transport model was formulated based on field measurements incorporated into the advection-dispersion equation. Key coefficients for the dispersion rate and velocity/dispersion ratio were quantified, allowing simulation of concentration changes under differing scenarios. Model predictions closely aligned with observed metal distribution patterns. Findings highlight the need for upgraded wastewater treatment and emissions controls to mitigate pollution over-burdening natural assimilative capacity. Continuous monitoring programs should track remediation effectiveness. This study provides insights to help authorities balance rapid industrialization, environmental protection and sustainable development goals through evidence-based regulatory strategies ensuring public health.

Microbiological quality of irrigation water on highly diverse fresh produce smallholder farms: elucidating environmental routes of contamination.

To evaluate the microbiological safety, potential multidrug-resistant bacterial presence and genetic relatedness (DNA fingerprints) of Escherichia coli isolated from the water-soil-plant nexus on highly diverse fresh produce smallholder farms. Irrigation water (n=44), soil (n=85), and fresh produce (n=95) samples from six smallholder farms with different production systems were analysed for hygiene indicator bacterial counts and the presence of shigatoxigenic E. coli and Salmonella spp. using standard microbiological methods. Identities of isolates were confirmed using matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS), and the genetic relatedness of the E. coli isolates determined using enterobacterial repetitive intergenic consensus polymerase chain reaction (ERIC-PCR) analysis. Irrigation water E. coli levels ranged between 0 and 3.45 log MPN/100 ml-1 with five farms having acceptable levels according to the World Health Organization limit (3 log MPN/100 ml-1). Fresh produce samples on four farms (n=65) harboured E. coli at low levels (<1 log CFU/g-1) except for one sample from kale, spring onion, green pepper, onion, and two tomato samples, which exceeded international acceptable limits (100 CFU/g-1). Only one baby carrot fresh produce sample tested positive for Salmonella spp. Of the 224 samples, E. coli isolates were identified in 40% (n=90) of all water, soil, and fresh produce types after enrichment. Additionally, the DNA fingerprints of E. coli isolates from the water-soil-plant nexus of each respective farm clustered together at high similarity values (>90%), with all phenotypically characterized as multidrug-resistant. The clustering of E. coli isolated throughout the water-soil-plant nexus, implicated irrigation water in fresh produce contamination. Highlighting the importance of complying with irrigation water microbiological quality guidelines to limit the spread of potential foodborne pathogens throughout the fresh produce supply chain.

Study of the levels of some heavy metals present in the cement dust of Al-Mergib factory

In this study, the concentrations of heavy metals (lead, nickel, and copper) in the cement dust of a factory were estimated using an Atomic Absorption Spectrophotometer technique. Three samples were taken from the factory chimney at different locations and times. The first sample revealed the highest concentration of elements during examination (on the upper part of the chimney) is lead (about 30.7 mg/l), nickel (6.9 mg/l), and copper (1.697 mg/l). The lead concentration decreased slightly in the second sample (mid-chimney), but it is still the most abundant element in this sample (30.1 mg/l). And in the third sample (below the chimney), the lead concentration decreased slightly (29.7 mg/l), then Cooper, and Nickel. All the metals studied were within the World Health Organization (WHO) limit nickel (200 mg/l) and copper (100 mg/l), except for lead (5 mg/l), higher than the permissible limit Keywords: Cement factory, Cement dust, Wet digestion, Heavy metals

Potentially toxic elements in soil-plant-water-animal continuum in a mining area from Northwestern Mexico: animal exposure pathways and health risks for children.

Mining increases environmental concentrations of potentially toxic elements (PTEs) accumulating in organisms and spreading in the human food chain-their presence in milk is of great human health concern. Pathways were identified by which these elements reach raw milk from farms within a mining area in Northwestern Mexico; health risks for dairy cattle and children were also evaluated. Water from river and cattle waterers, as well as, soils showed that PTE concentrations generally below the Mexican and international limits; cattle forage concentrations were above the World Health Organization limits. Al, Mg, Mo, Ni and Zn were recorded in raw milk samples from the mining area, showing that Cd, Co, Cr, Cu, Pb and V are transferred from soil to plants but not accumulated in raw milk. Zn concentrations in raw milk exceeded the permissible limit; milk from farms without mining operations (comparison site) showed the presence of Al, Cr and Cu. In cattle tail hair, PTE did not correlate with raw milk concentrations. Metal accumulation in milk was higher through water consumption than that accumulated through forage consumption. Daily intakes (DI) of Al, Mg and Zn in cows could represent a risk for their health. The observed biotransference was higher than in other parts of Mexico, and the calculated DI and hazard quotients indicate no adverse health effects for children. However, the hazard Index values indicate that exposure to multiple PTE represents a risk for children. Management measures should be performed to control the cumulative risks to protect young children's health.

Assessment of Groundwater Quality around Amaenyi and State Secretariat Dumpsites in Awka, Southeastern Nigeria

The effects of two dumpsites located at Amaenyi and State Secretariat Awka on groundwater resources was investigated using hydrochemical parameters. A total of eighteen (18) groundwater samples were collected from areas in the vicinity of the dumpsites and analysed for various hydrochemical and biological parameters using standard methods. The results of the analysis were subjected to interpretations using various methods such as spatial distribution maps, water quality indices (WQI, HPI, Cd and MEI), comparing with international and local standards and statistical analysis. The results indicate that parameters such as Ec, TDS, Na+, K+, Ca2+, Cl-, NO3- and SO42- were in compliance with the acceptable limits of World Health Organization and Nigerian Drinking Water Standard. However, HCO3-, total hardness, COD, BOD, DO1, DO5, Pb, Fe, Cd and Hg exceeded the permissible guidelines in some samples. WQI rated 20% of the samples in Amaenyi as excellent, 30% (good), 10% (poor), 20% (very poor) and the remaining 20% is unfit for consumption while in State Secretariat area, 37.5% was very poor and the remaining 62.5% was unfit for consumption. HPI rated groundwater as highly contaminated while Cd classified most of the water samples to indicate low contamination except for sample A1 which was highly contaminated. Also, MEI indicated that groundwater has low heavy metal pollution. The correlation analysis indicates strong positive relationship between BOD, COD, DO1, DO5, total hardness, bicarbonate, calcium and sulphate, lead, magnesium and chloride. It was concluded that groundwater in the study area is mostly contaminated and the contaminants is attributed to be from the waste dumpsites and other anthropogenic activities.

Scenedesmus sp. MN738556 as a whole cell biosensor for sub-part per billion detections of Cd2+ cations in freshwater sources

Recent increases in human activity and contamination of the marine environment have led to the advent of biosensors as sensitive, easy-to-operate, and rapid devices for water pollution screening. In the present study, a whole-cell electrochemical biosensor based on the native green microalgae Scenedesmus sp. MN738556 was developed, for the first time, to assess the biotoxicity of Cd2+ ions in freshwater. This electrochemical biosensor was constructed by immobilization of microalgae-BSA film on a glassy carbon electrode surface. The biosensor responses were based on chronoamperometric currents generated by alkaline phosphatase (ALP) activity. Since Cd2+ ions have an inhibition effect on ALP, the reduction in the general current can be used to determine the toxicity degree of these ions. The feasibility was evaluated and the application of the biosensor was optimized for parameters such as pH and cell density. The sensitivity of the biosensor was verified through the IC50 value of 0.26 ppb for Cd2+cation with the LOD of 0.1 ppb at pH 8.5 and 107 cells/mL. These values are practical for natural water environment monitoring based on the World Health Organization limit (3 ppb for Cd2+ ions in drinking water). The selectivity of the fabricated biosensor was investigated in binary mixtures of other divalent cations such as Zn2+, Ni2+, Cu2±, and Hg2+ at 1:1 and 1:10 ratios. The results indicated that the fabricated Scenedesmus biosensor is highly sensitive with a good selectivity at a 1:1 ratio for measuring the concentration of Cd2+ cations except in the presence of Hg2+. Moreover, this biosensor could respond with only one drop of an analyte (50 μL of 1000 ppb Cd2+ ions), resulting in suitability for simple and on-site water toxicity testing. Finally, two real freshwater samples were selected to prove the reliability, reproducibility, and performance of the Scenedesmus biosensor for the detection of Cd2+ cations discharges in the aquatic environment.

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.

Evaluation of Geology and Hydrochemistry of Nawfia-Agulu Axis of Anambra State, Southeastern Nigeria

The investigation of the geological, hydrochemical, and engineering characteristics of the Nawfia – Agulu area was carried out. The study aimed at mapping the geology through field data collection, outcrop logging, and laboratory analysis. Consequently, eleven soil and ten water samples were collected and analyzed through particle size distribution test; Atterberg limits tests and hydrochemical analysis to provide insights into the lithology, sediment characteristics, and water quality. The results indicated the dominance of the Ameki/Nanka Formation and Imo Formation as the underlying geology of the study area. The grain sizes of the sand samples ranged from medium to coarse grained, moderately to poorly sorted, and strongly positive to positively-skewed. The depositional environment was nearshore/beach, influenced by nearshore waves and turbulent currents. Engineering properties highlighted the prevalence of uniformly to well-graded soil and moderately to highly plastic behavior, as indicated by the mean plasticity index (PI) value of 26%. These findings suggest potential challenges for infrastructural development in some parts of the area. The water quality indicated slightly acidic water. The physical parameters and the major ions were within the permissible limits of World Health Organization (WHO) and the Nigerian Standard for Drinking Water Quality (NSDWQ). However, elevated concentrations of heavy metals, including lead, chromium, mercury, iron, and cadmium, in water sources exceeded the respective permissible limits for drinking water indicating contamination/pollution. The dominant water type was Ca2+ – Mg2+– SO42- – Cl– and the dominant hydrochemical process was simple dissolution or mixing and ion-exchange.

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 the status of selected heavy metals in water, sediments and a fish species (Oreochromis niloticus) of commercial value in Lake Nakuru with a focus on human health risks

AbstractThe present study presents selected water quality parameters and the levels of heavy metals in water, sediments and Nile tilapia (Oreochromis niloticus) of Lake Nakuru. Nine sediments and nine water samples, as well as 30 specimens of Nile tilapia, were collected from the northern part of the lake. Physical parameters were measured in situ using multiple probes and metres. Heavy metals were analysed using an atomic absorption spectrophotometer (AAS). The pH, dissolved oxygen concentration, temperature, salinity and electrical conductivity ranged from 9.52 to 9.72, 4.58 to 8.62 mg/L, 23.40°C to 25.7°C, 2.39‰ to 2.81‰ and 4470–5226 μs/cm, respectively. Heavy metal levels (mean ± SD) were generally low in the water samples. Chromium values ranged between 7.16 and 9.19 mg/kg dw in sediment samples, and between 3.7 and 13.06 mg/kg dw in fish samples. Lead values ranged between 12.5 and 31.04 mg/kg dw in sediment samples and 4.06 and 9.95 mg/kg dw in fish samples. Arsenic values ranged between 9.5 and 21.7 mg/kg dw in sediments and below detectable limit to 2.11 mg/kg dw in fish samples. Mercury values ranged between .14 and .31 mg/kg dw in sediment samples and .12 and .35 mg/kg dw in fish samples. Cadmium was the only heavy metal concentration that was below the detection limit in the three matrices. Significant differences were observed for some heavy metal concentrations in water, sediments and fish across sites (p &lt; .05). The levels of lead and chromium in fish were above the East African Standard, World Health Organization and European Union limits. The results of the present study recommend a possible reclassification of the lake, an immediate ban on fish harvesting and consumption from Lake Nakuru and a policy intervention on the fishery and pollution management.

Status of Selected Heavy Metals in Soils Samples Obtained From Crown Estate Dumpsite, Okada, Edo State, Nigeria

This research work focused on the status of selected heavy metals in dumpsite soil compared with soil samples obtained from a green park area as a control. The research results were also related to threshold limits set by the National Environmental Standards and Regulations Enforcement Agency (NESREA), World Health Organization (WHO) and Food and Agriculture Organization (FAO). Soil samples were collected from a dumpsite inside Crown Estate (made up of residential quarters for both staff and students of Igbinedion University) and a green area of Igbinedion University's permanent site, Okada, Benin City, Edo State in Nigeria. The soil samples were air-dried, ground, sieved, digested and subjected to heavy metal analysis using atomic absorption spectroscopy. The analyzed metal profiles in the dumpsite soil samples are as follows: concentration of Fe, Pb, Cu, Zn, Mn and Ni ranged from 453.26 – 569.28, 0.85 – 1.16, 20.17 – 32.35, 60.98 – 74.26, 5.15 – 9.28, and 5.92 – 9.57 mg/Kg, with mean concentrations of 501.33 mg/Kg, 0.96 mg/Kg, 25.38 mg/Kg, 66.33 mg/Kg, 6.89mg/Kg and 7.90 mg/Kg respectfully, while the status of heavy metal concentration in soil samples collected from the control site ranged from 386.21 – 463.95, 0.82 – 1.32, 20.05 – 26.27, 47.75 – 65.22, 5.77 – 8.73, and 6.35 – 9.87 mg/Kg, with mean concentration of 401.76 mg/Kg, 1.05 mg/Kg, 23.05 mg/Kg, 54.84, 7.39 mg/Kg and 7.78 mg/Kg for Fe, Pb, Cu, Zn, Mn and Ni respectfully. Of all the metals analyzed only the level of Fe in this study did exceed the tolerance limits of NESREA, WHO and FAO. The results also revealed higher heavy metal content in the dumpsite justifiably due to the difference in anthropogenic activities carried out on the two sites.

Assessing Groundwater Level and Water Quality in Bhaktapur Municipality: A Pre-Monsoon and Post-Monsoon Analysis

Groundwater is a crucial natural resource for sustaining human life, agriculture, and ecosystems worldwide. In many Asian countries, including Nepal, groundwater has emerged as a dependable source of water, particularly in areas where surface water is scarce or unreliable. For instance, in Bhaktapur Municipality (BM), Nepal, groundwater has been contributing around 50–60% of the total water supply. However, over the past few years, extensive extraction, alterations in the land use pattern, and other anthropogenic interventions have posed serious threats to this highly valuable resource. As such, groundwater monitoring is an essential primary step for understanding the status of the groundwater resource. Meanwhile, the Water Quality Index (WQI) is an effective tool that can turn complex water quality data into simplified information that is understandable and usable by the public. This study aimed to understand the groundwater levels and further comprehend the groundwater quality using the WQI of the BM. The groundwater level data and water samples were collected from 24 spatially distributed wells of the BM in the post-monsoon of 2021 and the pre- and post-monsoon of 2022. Laboratory analysis was carried out to determine the nine physico-chemical water quality parameters, and the obtained parametric values were compared with those of the World Health Organization (WHO) and the National Drinking Water Quality Standard (NDWQS). The results show deeper groundwater levels in the core area than the periphery, and the water quality getting poorer from post-monsoon 2021 to post-monsoon 2022. The EC, TDS, pH, phosphate, chloride, and hardness of most of the samples were within the permissible limits of WHO and NDWQS, whereas the turbidity, ammonia, and alkalinity of many samples exceeded the permissible limits. Average WQI revealed that the majority of the samples were unsuitable for drinking and suitable only for household and irrigation purposes. This study provides insights into managing water demands, addressing issues of water scarcity, and highlighting the urgent need for additional research and policymaking to improve drinking water quality and the sustainability of groundwater management in BM.

Exhaust Emission Assessment of Haulage Trucks at Onne Port, Nigeria

Haulage trucks are among the primary causes of air pollution in urban areas. The effect of air pollution caused by transportation, especially freight transportation, on public health is a major concern globally. In this study, emissions of haulage trucks operating at Onne Port, Rivers State in Nigeria were assessed to understand their contribution to local air pollution and environmental impact. Real-time measurements of air pollutants were taken using a portable Testo 350 Analyzer and a portable IGRESS Intelligent Detector from seventy (70) haulage trucks at Onne Port grouped according to production years, region of origin, and truck length, and the data obtained were compared with the World Health Organization (WHO) air quality standards. The results revealed that the trucks’ emissions exceeded WHO limits for six criteria pollutants, including NO2, SO2, CO, PM1, PM2.5, and PM10, which are associated with adverse health effects such as respiratory and cardiovascular diseases. Other notable findings included higher concentrations of NO2 at 35.48 ppm and PM2.5 at 300.73 µg/m3 from trucks produced between 2011 and 2021, while older trucks exhibited increased emissions of SO2 at 31.16 ppm, CO at 775.87 ppm, PM1 at 216.75 µg/m3, and PM10 at 341.75 µg/m3. There were no significant variations in pollutant emission concentrations observed within the four categories across different production years. Trucks manufactured in Asia consistently emitted lower pollutant concentrations compared with those from other regions, suggesting the influence of varying emission standards. Interestingly, truck length did not significantly impact emission levels. These findings underscore the urgency of addressing the air quality issues associated with haulage trucks in the region, highlighting the need for stringent emissions control measures.

Assessment of heavy metal distribution and bioaccumulation in soil and plants near coal mining areas: implications for environmental pollution and health risks.

Monitoring heavy metals (HMs) across source distance and depth distribution near coal mining sites is essential for preventing environmental pollution and health risks. This study investigated the distribution of selected HMs, cadmium (Cd2+), chromium (Cr2+), copper (Cu2+), manganese (Mn2+), nickel (Ni2+), lead (Pb2+), and zinc (Zn2+), in soil samples collected from ten sites (S-1-S-10) at two different depths (0-15 and 15-30 cm) and distances of 50, 100, and 200 m from a mining source. Additionally, three plant species, Prosopis spp., Justicia spp., and wheat, were collected to assess HM bioavailability and leaf accumulation. Coal mine activities' impact on soil properties and their HM associations were also explored. Results reveal HM concentrations except for Cr2+ exceeding World Health Organization (WHO) limits. In surface soil, Cd2+ (58%), Cu2+ (93%), Mn2+ (68%), Ni2+ (80%), Pb2+ (35%), and Zn2+ (88%) surpassed permissible limits. Subsurface soil also exhibited elevated Cd2+ (53%), Cu2+ (83%), Mn2+ (60%), Ni2+ (80%), Pb2+ (35%), and Zn2+ (77%). Plant species displayed varying HM levels, exceeding permissible limits, with average concentrations of 1.4, 1.34, 1.42, 4.1, 2.74, 2.0, and 1.98 mg kg-1 for Cd2+, Pb2+, Cr2+, Cu2+, Mn2+, Ni2+, and Zn2+, respectively. Bioaccumulation factors were highest in wheat, Prosopis spp., and Justicia spp. Source distance and depth distribution significantly influenced soil pH, electrical conductivity (EC), and soil organic carbon (SOC). Soil pH and EC increased with an increase in soil depth, while SOC decreased. Pearson correlation analysis revealed varying relationships between soil properties and HMs, showing a considerably negative correlation. Concentrations of HMs decreased with increasing depth and distance from mining activities, validated by regression analysis. Findings suggest crops from these soils may pose health risks for consumption.

Temporal Variation of Indoor (a residential space) and Outdoor PM2.5 in Male’, Maldives

This study aims to assess the Indoor Air Quality (IAQ) inside a one room apartment of about 240 square feet in the Henveiru district in Male’, Maldives. Concentrations of Particulate Matter (PM2.5), one of the most detrimental air pollutants, were measured every 15 minutes from 10-09-2021 to 18-12-2021 using low-cost PM BlueSky sensors inside the building (indoor) and simultaneously outdoor, about 300m away from the indoor sensor. The BlueSky monitors were co-located and harmonized before starting the monitoring. The mean concentrations observed indoor and outdoor for 93 days were 10.1±13.1 µg/m3 and 6.5±4.9 µg/m3, respectively. Both results surpass the annual average of 5 µg/m3 guideline of World Health Organization (WHO). The number of days that surpassed the 24-hour WHO limit was 9 for indoor and 7 for outdoors. The diurnal pattern of PM2.5 shows a drastic accumulation of the pollutant inside the building when the only available ventilation (the window) was closed, which was identified at night and also during the daytime. The recorded PM2.5 levels also aligned with household activities like cooking, cleaning, and dusting. There was a significant moderate correlation (r= 0.48) between outdoor and indoor PM2.5. The I/O ratio was 1.95±3.01 indicating the presence of more indoor sources. This study serves as a preliminary assessment of indoor air quality in Male’, Maldives. Based on its findings, efforts should be directed towards ensuring proper ventilation in residential spaces and continuously monitoring air quality in more location for longer periods to ensure healthy IAQ.