Abstract

Phthalate esters (PAEs) are widely used plasticizers with recognized environmental and health risks, yet little is known about their occurrence in unmanaged dumpsites in the Niger Delta. This study assessed PAE levels in soils from eight dumpsites across Isoko North and South Local Government Areas, Delta State, Nigeria. A total of 24 composite soil samples were collected between April and June 2025 and analyzed using gas chromatography–mass spectrometer (GC-MS). Carcinogenic and non-carcinogenic assessment was carried out. Quality assurance was done. Results showed that total PAE concentrations ranged from 10.6±1.00 ng/g to 43.5±6.70 ng/g, with Bis(2-Ethylhexyl) Phthalate (DEHP), Diethyl Phthalate (DEP) and Dimethyl Phthalate (DMP), as dominant congeners. Health risk assessment revealed no potential health risk associated with PAEs in the dumpsite soils. Principal component analysis and hierarchical cluster analysis indicated that the PAEs in the soils were from diverse sources. The findings demonstrate that unmanaged dumpsites in the Isoko areas of Delta State serve as reservoirs of persistent PAEs, with implications for soil quality, groundwater safety, and human health. While current levels may not pose immediate concern, the persistence of PAEs highlights the need for regular monitoring, improved waste management, and policy measures to prevent long-term ecological and human health impacts.

Keywords: Phthalate esters, Dumpsite soils, Niger Delta, Health risk assessment, Waste management