ABSTRACT:The objective of this study was to determine the level of phthalate ester plasticizers in Ethiope River water samples. Gas chromatography (GC) coupled with mass spectrometer (MS) was used to evaluate the levels of dimethyl phthalate (DMP), diethyl phthalate (DEP), dibuthyl phthalate (DBP), diethylhexyl phthalate (DEHP), buthylbenzyl phthalate (BBP), di-n-octyl phthalate (DnOP in the water samples. Range of total phthalate level in different locations fell between 0.74µg/L and 1.75µg/L. It was found that Sapele-1 and Sapele-2 had highest total phthalates concentrations. The highest concentrations of phthalates were DBP and DEHP, which is consistent with their common use in plastic materials and other industrial chemicals. It was found that the individual phthalates concentration was low but total phthalate levels were high in most stations. The results for phthalates in the water samples is low but there is the need to guide against an upward rise in the concentrations as these may pose grave environmental and health concern for people living downstream of the river. These results can be used as reference levels for future monitoring programs for pollution studies of the river. © JASEM http://dx.doi.org/10.4314/jasem.v20i3.15Key words: phthalates, acid esters, plasticizers, Ethiope River, surface water, pollution Most of the consumer products in our homes consist of additives known as ester plasticizers. They are group of synthetic compounds which are added to products in order to enhance flexibility and durability of the product (Schettler, 2006;Daiem, 2012).Phthalate ester plasticizers provide an array of benefits required for the many applications such as tubing and hose products,personal care products, household furnishing, building materials, children's toys, medical devices, flooring, wall-coverings, seals and gaskets, belts, wire and cable, and print rolls (Gao et al., 2014;Wang et al., 2015). More than three million metric tonnes of phthalates are produced annually. Phthalate plasticizers are not chemically bound to materials; they can leach at a constant rate from plastic products to the environment and consequently, are distributed in the ecosystem and have been described as the most abundant man-made environmental pollutant (Latini2005; Vitali et al., 1997;Zhang et al., 2015).They found ubiquitously in the environment as primarily diethylhexyl phthalate (DEHP), dibutyl phthalate (DBP) and in much lower concentrations dimethyl phthalate (DMP), diethyl phthalate (DEP), and Butylbenzyl phthalate (BBzP or BBP), di-n-octyl phthalate (DnOP), diisononyl phthalate (DINP) Humans are exposed to phthalate mainly via ingestion, inhalation and dermal exposure (Adibi et al., 2003). Phthalate are becoming a great environmental concern because of their ubiquitous nature and studies have indicated various reproductive toxicities and carcinogenic potentials. Phthalates are now known to cause a broad range of birth defects and lifelong reproductive impairment in laboratory animals exposed in-utero (Ema et al., ...