Level, Distribution, Ecological and Human Health Risk Assessment of Heavy Metals in Dust Samples in Akure South, Ondo State, Nigeria

This study investigates the concentrations of heavy metals in dust samples collected from various locations in Akure metropolis, Nigeria, and assesses their potential ecological and human health risks based on international guidelines. Metals analyzed include lead (Pb), cadmium (Cd), mercury (Hg), arsenic (As), chromium (Cr), and nickel (Ni). Results indicate diverse contamination levels across sampling sites, reflecting both industrial and traffic-related emissions. Lead concentrations averaged 28.5 mg/kg, with localized peaks exceeding the WHO limit of 85.00 mg/kg, posing significant health risks, especially in high-traffic zones. Cadmium levels averaged 6.2 mg/kg, surpassing the WHO guideline of 0.80 mg/kg, indicating substantial contamination and potential health concerns due to its toxicity. Mercury averaged 0.85 mg/kg, below the WHO threshold, suggesting minimal health risks despite localized higher concentrations. Arsenic and chromium levels averaged 1.4 mg/kg and 4.3 mg/kg, respectively, both below their respective WHO limits. Spatial distribution maps highlight hotspots of contamination, correlating with industrial and urban development areas. Ecological risk assessments using potential ecological risk index (PERI) indicate moderate to high risks, particularly for Pb and Cd, with implications for local ecosystems. Human health risk assessments consider exposure through dust ingestion, dermal contact, and inhalation pathways, revealing elevated hazard indices (HI) in certain residential and industrial zones. Principal Component Analysis (PCA) identifies sources of contamination, attributing significant contributions to industrial emissions and vehicular exhaust. The study underscores the urgent need for regulatory measures and remediation strategies to mitigate heavy metal pollution in Akure metropolis, safeguarding both environmental quality and public health. This abstract summarizes the study findings on heavy metal contamination in Akure metropolis, highlighting specific concentrations, distribution patterns, ecological risks, and implications for human health based on WHO guidelines and analytical methods