Environmental pollution is a pressing global issue with far-reaching implications for human and ecological well-being. As we rely more on fossil fuels, improper sewage disposal, and excessive pesticide use, the problem becomes increasingly pervasive. In developing countries like Nigeria, industrial growth and the indiscriminate disposal of waste have become major concerns. These wastes often contain hazardous chemicals that can infiltrate and accumulate in the environment, contaminating soil, water bodies, and entire ecosystems.
The impact of industrial effluents on hydrological and environmental parameters is significant, posing threats to both humans and ecosystems. Accumulation of hazardous pollutants in soil, water, and air leads to health risks and environmental degradation. Hazardous wastes, characterized by their flammability, reactivity, explosiveness, and toxicity, are a growing concern. Wastes from industries such as fertilizers, paints, dyes, pharmaceuticals, and heavy metal-containing products, as well as vehicle maintenance and battery industries, are classified as hazardous.
For instance, the waste from battery industries, when thrown as garbage, can corrode and release toxins, contaminating land and water. Similarly, the textile industry generates solid waste, sludge, and other by-products that can present problems due to their surplus volumes and unwanted composition, often containing high loads of organic matter, micronutrients, heavy metal cations, and pathogenic microorganisms.
Fertilizer industries are also a source of natural radionuclides and heavy metals, leading to water, soil, and air pollution. Improper use of fertilizers and pesticides can further contaminate agricultural soil, making it a potential source of pollution. The production of paints also contributes to high concentrations of organic acid compounds, suspended solids, colored materials, and hazardous pollutants like heavy metals in the generated waste.
Dump sites, the main receptacles for domestic and industrial waste, are often turned into other land uses, such as crop cultivation or residential areas, without proper assessment of the health risks they pose. These sites can emit obnoxious odors and smoke, causing illness to nearby residents. Despite their importance and prevalence, dump sites, especially in Nigeria, have been sparsely studied, particularly regarding their mineral and toxic content.
The current study aims to assess the ecological and human health risks of soils and water samples from the vicinities of dumpsites in residential and selected industrial layouts in Benue State, Nigeria. The study focuses on dumpsites associated with fertilizer, dye, battery, and paint industries within the Makurdi metropolis.
Soil samples were collected from these sites and analyzed for their physicochemical parameters, heavy metal concentrations, and ecological risk indices. The results revealed varying levels of contamination, with some sites showing high concentrations of heavy metals like lead, chromium, cadmium, and copper. The ecological risk assessment indicated that the studied dumpsites pose a high risk of pollution, with potential adverse ecological impacts.
The human health risk assessment, based on chronic daily intake, hazard quotient, and hazard index, showed that the risk of non-carcinogenic health effects was low. However, the study highlights the potential future risk posed by the degraded soil ecosystem, particularly through bioaccumulation in crops and livestock, and the possibility of new exposure pathways with changes in land use.
The findings emphasize the need for preventive measures, such as restricting agriculture and settlement on these sites, and continuous monitoring to mitigate potential health impacts. The study contributes to a better understanding of the environmental and health risks associated with dumpsites, providing valuable insights for policy-making and waste management strategies.
