Disinfection Byproducts in Drinking Water and Evaluation of Potential Health Risks of Long-Term Exposure in Nigeria

Levels of trihalomethanes (THMs) in drinking water from water treatment plants (WTPs) in Nigeria were studied using a gas chromatograph (GC Agilent 7890A with autosampler Agilent 7683B) equipped with electron capture detector (ECD). The mean concentrations of the trihalomethanes ranged from zero in raw water samples to 950 μg/L in treated water samples. Average concentration values of THMs in primary and secondary disinfection samples exceeded the standard maximum contaminant levels. Results for the average THMs concentrations followed the order TCM > BDCM > DBCM > TBM. EPA-developed models were adopted for the estimation of chronic daily intakes (CDI) and excess cancer incidence through ingestion pathway. Higher average intake was observed in adults (4.52×10-2 mg/kg-day), while the ingestion in children (3.99×10-2 mg/kg-day) showed comparable values. The total lifetime cancer incidence rate was relatively higher in adults than children with median values 244 and 199 times the negligible risk level

Reliability of stored river water as an alternative for consumption in Ekpoma, Nigeria: a human health risk assessment

With looming global water-related issues, the monitoring of water quality for household and industrial consumption has become more pertinent. Rivers in nearby towns serve as primary water sources for Ekpoma town. 123 samples of stored river water were collected from 41 sampling locations and physical properties - pH, electrical conductivity (EC), salinity, temperature, and total dissolved solids (TDS) - were measured in situ using the Hanna edge® Multiparameter EC/TDS/Salinity Meter-HI2030. Atomic absorption spectrophotometry (AAS) was used to detect and measure the concentration of potentially toxic metals (PTMs): Al, Cr, Cu, Fe, Mn, Ni, Pb, and Zn. The measured concentrations were compared to the WHO, US EPA, and NSDWQ regulatory standards, and a spatiotemporal health risk analysis was performed using HERisk software. Twenty-five percent of the tested samples contained PTM concentrations within the allowable regulatory limits. Spatiotemporal health risk analysis showed that 98.8% of the cumulative carcinogenic risks (CRcum) were entirely from Pb contamination via oral ingestion. PTM concentrations in the samples suggest the degradation of river water quality due to agricultural activities, crude oil exploration activities, and soil composition in the region. Best management practices (BMPs) and treatment processes for the removal of detected contaminants are recommended to improve water quality

Review

Previous surgical procedures devised for intractable pain are the excision of painful area of the skin, peripheral neurotomy, intraspinal or intracranial posterior rhizotomies, anterolateral spinal cordotomy, spinothalamic tractotomy at medulla and mesencephalon for the pain of organic origin, and the prefrontal lobotomy for psychogenic pain. Unfortunately, these procedures are followed either by disturbance of physiologic sensory function or by changes of affect and personality. Partial gasserian gangliolysis successfully alleviated the trigeminal neuralgia without significant sensory disturbance of the face. Recent advances in stereotaxic technique has enabled us to attack the thalamus and other deep subcortical centers. This new method, together with recent neuroanatomico-physiological progress in regard to pain tract through intralaminar nuclear complex, resulted in discovery of thalamotomy destroying the nucleus centrum medianum with or without adjacent intralaminar nuclei, which eliminates the organic pain without any detectable sensory deficit. Anterior cingulectomy or cingulumotomy has developed to alleviate the psychogenic pain without psychological changes. These are the ideal pain-relieving procedures. A new method of percutaneous cervical cordotomy can be safely used for the debilitated patients with terminal malignant diseases

Assessing the state of rainwater for consumption in a community in dire need of clean water: Human and health risk using HERisk

This study examines the case of Ekpoma community, Edo State, Nigeria, where roof-harvested rainwater is the primary source of water for drinking and domestic purposes. Eight potentially toxic elements (PTEs), namely aluminum, chromium, copper, iron, manganese, nickel, lead, and zinc, were detected in rainwater samples, collected and analyzed from 54 sampling locations across the community. The elemental concentrations were quantified using atomic absorption spectrophotometry and compared using the regulatory standards of the World Health Organization, United States Environmental Protection Agency, and Nigerian Drinking Water Quality Standards. The PTEs detected in the rainwater samples can be attributed to the nature of the materials used in the roof catchment systems, storage tank conditions, anthropogenic effects from industrial and agricultural processes, and fossil fuel emissions. However, only 20% of the evaluated samples contained PTE concentrations below the allowable regulatory limits. Spatio-temporal health risk analysis conducted using HERisk software showed that children in the development phase (1–18 years) are most vulnerable to health risks in the community. After age 18, the risk increased by approximately 10% and remained constant until old age. In addition, the evaluation of the studied sites showed that 33% of the evaluated sites had negligible carcinogenic risks, while the other 61% were sites with low carcinogenic risks to residents

Source Evaluation and Trace Metal Contamination in Benthic Sediments from Equatorial Ecosystems Using Multivariate Statistical Techniques

race metals (Cd, Cr, Cu, Ni and Pb) concentrations in benthic sediments were analyzed through multi-step fractionation scheme to assess the levels and sources of contamination in estuarine, riverine and freshwater ecosystems in Niger Delta (Nigeria). The degree of contamination was assessed using the individual contamination factors (ICF) and global contamination factor (GCF). Multivariate statistical approaches including principal component analysis (PCA), cluster analysis and correlation test were employed to evaluate the interrelationships and associated sources of contamination. The spatial distribution of metal concentrations followed the pattern Pb>Cu>Cr>Cd>Ni. Ecological risk index by ICF showed significant potential mobility and bioavailability for Cu, Cu and Ni. The ICF contamination trend in the benthic sediments at all studied sites was Cu>Cr>Ni>Cd>Pb. The principal component and agglomerative clustering analyses indicate that trace metals contamination in the ecosystems was influenced by multiple pollution sources

Data on quantification of PAHs and elemental content in dry Camellia sinensis and herbal tea

Here we present data on potentially toxic metals and polycyclic aromatic hydrocarbons (PAHs) in commercially sold tea brands in Nigeria. The article provides data on the sequential extraction and the pseudo-total concentrations of eight metals (Cd, Cr, Cu, Mn, Ni, Pb, V and Zn) and polycyclic aromatic hydrocarbons (PAHs) in dry Camellia sinensis and herbal tea. The three-step Community Bureau of Reference (BCR) method and acid digestion with aqua regia were adopted for sequential and total metal extractions, respectively. The extraction of branded tea samples for PAHs analysis has been described in “Concentrations, sources and risk characterisation of polycyclic aromatic hydrocarbons (PAHs) in green, herbal and black tea products in Nigeria” [1] and “Polycyclic Aromatic Hydrocarbons (PAHs) Occurrence and Toxicity in C. sinensis and Herbal Tea” [2]. Elemental and PAHs analyses of extracts were determined by Microwave Plasma Atomic Emission Spectroscopy (Agilent MP-AES 4100) and Agilent gas chromatograph 7890A coupled with flame ionization detector (FID), respectively

Coastal Vulnerability Assessment: A Case Study of the Nigerian Coastline

Coastal regions are one of the essential spots on the earth as they are hosts to various important ecosystems, natural resources and the increasing population. Based on their proximity to the seas, they are mainly affected by sea-level rise, which is one of the adverse effects of climate change. This has resulted in associated hazards, such as beach erosion, flooding, coastal inundation, habitat destruction, saltwater intrusion into ground water aquifers and ecosystem imbalance. This study quantifies and classifies the vulnerability of the Nigerian coastline to these threats using the analytical hierarchical approach. This involved calculating the coastal vulnerability index (CVI) employing physical and geomorphological variables, and socioeconomic indicators that characterized the coastline vulnerability. The Nigerian coast was divided into seventeen (17) segments based on geomorphic units. The different vulnerability variables were assigned ranks ranging from 1 to 5, with 5 indicating the highest and 1 indicating the lowest vulnerabilities. The geomorphological and physical parameters include coastal slope, bathymetry, geomorphology, wave height, mean tidal range, shoreline change rate and relative sea-level rise, while the socioeconomic parameters include population, cultural heritage, land use/land cover and road network. The calculated CVI values (Saaty method) ranged from 11.25 to 41.66 with a median value of 23.60. Based on Gornitz approach, the calculated measures ranged between 3.51–4.77 and 3.08–5.00 for PVI and SoVI, respectively. However, the aggregated coastal vulnerability index computed using this approach ranged from 3.29 to 4.70. The results obtained from both approaches showed that 59–65% of the entire Nigerian coastline is under moderate to high vulnerability to sea-level rise. Data indicted how the coastal populations are highly vulnerable to both physical–geomorphological and socioeconomic stressors. Coastal vulnerability maps, highlighting the physical–geomorphological and socioeconomic vulnerability status of Nigerian coastline were also generated. The information from this study will assist coastal planners in identifying vulnerable segments in the study area and subsequently aid decisions that would mitigate the predicted impacts in the region

Coastal Vulnerability Assessment: A Case Study of the Nigerian Coastline

Coastal regions are one of the essential spots on the earth as they are hosts to various important ecosystems, natural resources and the increasing population. Based on their proximity to the seas, they are mainly affected by sea-level rise, which is one of the adverse effects of climate change. This has resulted in associated hazards, such as beach erosion, flooding, coastal inundation, habitat destruction, saltwater intrusion into ground water aquifers and ecosystem imbalance. This study quantifies and classifies the vulnerability of the Nigerian coastline to these threats using the analytical hierarchical approach. This involved calculating the coastal vulnerability index (CVI) employing physical and geomorphological variables, and socioeconomic indicators that characterized the coastline vulnerability. The Nigerian coast was divided into seventeen (17) segments based on geomorphic units. The different vulnerability variables were assigned ranks ranging from 1 to 5, with 5 indicating the highest and 1 indicating the lowest vulnerabilities. The geomorphological and physical parameters include coastal slope, bathymetry, geomorphology, wave height, mean tidal range, shoreline change rate and relative sea-level rise, while the socioeconomic parameters include population, cultural heritage, land use/land cover and road network. The calculated CVI values (Saaty method) ranged from 11.25 to 41.66 with a median value of 23.60. Based on Gornitz approach, the calculated measures ranged between 3.51–4.77 and 3.08–5.00 for PVI and SoVI, respectively. However, the aggregated coastal vulnerability index computed using this approach ranged from 3.29 to 4.70. The results obtained from both approaches showed that 59–65% of the entire Nigerian coastline is under moderate to high vulnerability to sea-level rise. Data indicted how the coastal populations are highly vulnerable to both physical–geomorphological and socioeconomic stressors. Coastal vulnerability maps, highlighting the physical–geomorphological and socioeconomic vulnerability status of Nigerian coastline were also generated. The information from this study will assist coastal planners in identifying vulnerable segments in the study area and subsequently aid decisions that would mitigate the predicted impacts in the region