Majority of people living on earth rely on groundwater as their primary supply of water for daily needs. However, human activities continuously threaten this natural resource. In an attempt to unravel the extent of impact of human-related activities on groundwater physicochemical characteristics in Nnewi and Awka urban clusters (Nigeria), several techniques were integrated in this study. Groundwater samples were warm and acidic in nature. Concentrations of SO₄^2-, NO₃^-, PO₄^3-, Cl^-, HCO₃^-, Ca²⁺, Mg²⁺, Na⁺, and K⁺ were within set benchmarks. Water nutrient pollution index (ranging from 0.060-0.745), nitrate pollution index (varying between -0.999 and -0.790), and water pollution index (ranging from 0.057-0.630) estimated the extent of anthropogenic contamination and showed low anthropogenic impact on the groundwater physicochemical characteristics. The health risks due to the ingestion and skin absorption of the nitrate-contaminated water computed for six age groups (6-12 months, 5-10 years, 10-15 years, 15-20 years, 20-60 years, and > 60 years) showed health risk values that were < 1, implying low chronic health risks to humans. The cumulative total health hazard index ranged between 0.006 and 0.787 with a mean value of 0.167. Chemometric analyses and geochemical plots revealed the relationships between the variables and contamination sources. Chadha’s plot showed that 55% of the samples were Ca²⁺-Mg²⁺-Cl^- waters, predominating over Na⁺-Cl^- and Ca²⁺-Mg²⁺-HCO₃^- waters. Bivariate and multivariate geochemical plots also indicated low anthropogenic impact. Furthermore, principal component analysis and R-type hierarchical clustering confirmed that the groundwater chemistry and quality were mostly influenced by geogenic processes than human-related acts. Conclusively, the extent of anthropogenic influence on the groundwater physicochemical characteristics is low. These findings would be useful in future monitoring of groundwater in both urban clusters.

Neurodegenerative and neuronal-related diseases are major public health concerns. Human vulnerability to neurodegenerative diseases (NDDs) increases with age. Neuronal hormones and neurotransmitters are major determinant factors regulating brain structure and functions. The implications of environmental and climatic changes emerged recently as influence factors on numerous diseases. However, the complex interaction of neurotransmitters and neuronal hormones and their depletion under environmental and climatic influences on NDDs are not well established in the literature. In this review, we aim to explore the connection between the environmental and climatic factors to NDDs and to highlight the available and potential therapeutic interventions that could use to improve the quality of life and reduce susceptibility to NDDs.

In this paper, the oral and dermal health risks of potentially toxic elements in water samples collected from Ojoto area in southeast Nigeria were studied using HHRISK code and water quality index. The water samples were analysed for physicochemical parameters based on standard guidelines. Average concentration of the potentially toxic elements in the water was in the order: Pb²⁺ > Fe²⁺ > Zn²⁺ > Ni²⁺ > Cr³⁺. To assess the level of surface and groundwater pollution, water quality index was calculated. Results of the water quality index suggest that 11% of the water samples are in good condition; 25% have poor quality, 3% have very poor quality, and 53% have quality that is unfit for human consumption. The HHRISK code was used to quantify the health risks associated with the use of the water resources. Results revealed that most of the water samples expose their users to carcinogenic and non-carcinogenic health risks. Cumulative non-carcinogenic risk scores (for both children and adults) and the majority of cumulative carcinogenic risk values were found to be above regulatory limits. The adult population is exposed to lower non-carcinogenic and carcinogenic health risks, implying that children are more vulnerable. The water supplies are of substandard quality and could cause serious health issues when ingested than when used for bathing and washing purposes. Simple linear regression models showed positive agreement between the results of the WQI and HHRISK code. To safeguard the water resources, avoid additional water contamination, and reduce public health hazards associated with poor water quality, strategic mitigation strategies are recommended.

Human health and the sustainability of the socioeconomic system are directly related to water quality. As anthropogenic activity becomes more intense, pollutants, particularly potentially harmful elements (PHEs), penetrate water systems and degrade water quality. The purpose of this study was to evaluate the safety of using groundwater for domestic and drinking purposes through oral and dermal exposure routes, as well as the potential health risks posed to humans in the Nnewi and Awka regions of Nigeria. The research involved the application of a combination of the National Sanitation Foundation Water Quality Index (NSFWQI), HERisk code, and hierarchical dendrograms. Additionally, we utilized the regulatory guidelines established by the World Health Organization and the Standard Organization of Nigeria to compare the elemental compositions of the samples. The physicochemical parameters and NSFWQI evaluation revealed that the majority of the samples were PHE-polluted. Based on the HERisk code, it was discovered that in both the Nnewi and Awka regions, risk levels are higher for people aged 1 to 65 than for people aged 16 to Pb > Cu > Fe for Nnewi and Pb > Cd > Cu > Fe for water samples from Awka. Summarily, groups of middle age are less susceptible to possible health issues than children and elderly individuals. Hierarchical dendrograms and correlation analysis showed the spatio-temporal implications of the drinking groundwater quality and human health risks in the area. This research could help local government agencies make informed decisions on how to effectively safeguard the groundwater environment while also utilizing the groundwater resources sustainably.