Distribution and Risk Evaluation of Phthalates in Omambala River Water and Sediment during the Wet Season in Anambra State, Nigeria

Abstract

Phthalates, under the list of an endocrine disruptor and persistent organic pollutants is identified by its contamination of the environment and toxicities. In this research, the distribution of selected phthalates was identified in the sampling site to discover their presence and the ecological and health risk assessment of these phthalates to the environment. The samples of water and sediments were taken as per standard procedures. Seven PAEs were extracted by solid phase and ultrasonic and analysed through Gas Chromatography with Mass Detector (GCMS). It was determined that the analytical average recovery was between 83.4 %. Their findings revealed that there was a high percentage of detection rate of PAEs in six of seven samples in water. The detection rate of di-n-butyl phthalate (DPB) and disobutyl phthalates (DIBP) was found to be higher than the detection rate of other PAE monomers. It was also established that the concentration of Phthalates (PAEs) was greater in the sediment samples than in water samples because of the fact that sediments are a sink of most persistent organic pollutants. The concentration of PAEs in water samples and sediments was also between 0.00 mg/kg to 0.028 mg/kg and 0.00 mg/l to 0.23 mg/l, respectively. The ecological risk assessment based on the risk quotient method (RQ) indicates that the estimated environmental risk by phthalates is under the moderate level since the risk quotient (RQ) falls between 0.1 to 1.0, and the health risk assessment based on phthalates on the determination of the average daily dose indicates that phthalates ingestion was found to be approaching the level that once reached, leads to severe carcinogenic event in the human body through an excess accumulation.