Assessment and Distributions of Phthalates Esters (PAEs) in Groundwater of Gbagi General Market in Ibadan and its Health Risk to the Environment

This study assessed the concentrations, spatial distribution, and associated health risks of selectedPAEs in groundwater around Gbagi General Market, Ibadan, Nigeria. A total of 8 groundwatersamples were collected and analyzed using High-performance liquid chromatography (HPLC).The target PAEs included diethyl phthalate (DEP), dibutyl phthalate (DBP), benzyl butyl phthalate(BBP), dimethyl phthalate (DMP), and di-(2-ethylhexyl) phthalate (DEHP). Results showed thatDEHP had the highest mean concentration of 5.73 μg/L, followed by DBP at 2.65 μg/L, BBP at1.12 μg/L, DEP at 0.07 μg/L, and DMP at 0.03 μg/L. Several samples exceeded the World HealthOrganization’s permissible limit for DEHP in drinking water (8 μg/L), with one sample recordingas high as 12.8 μg/L. Spatial analysis revealed contamination hotspots near plastic waste dumpsand drainage channels within the market. The cancer risk assessment revealed that although theestimated carcinogenic risks (CR) for both adults and children were within the acceptable rangedefined by (USEPA) threshold of 1 × 10⁻⁶ to 1 × 10⁻⁴, children exhibited higher lifetime cancerrisks compared to adults. DEHP a known probable human carcinogen, was the dominantcontributor to overall cancer risk, primarily through oral ingestion. This study demonstrates thesignificant chemical burden posed by PAEs in urban groundwater, due to improper plastic wastedisposal and intense commercial activity. The result of this findings call for urgent regulatoryintervention, improved market sanitation, and public awareness and provides essential baselinedata for environmental health surveillance and supports development of policies targetinggroundwater safety in Nigeria’s commercial centers.