Assessment of phthalic acid esters pollution in Anzali wetland, north of Iran

Due to ecological importance of Anzali wetland (in south of the Caspian sea) and taking the toxicity of phthalates into consideration, which can finally find their way to human diet and pose a huge threat to human food security, the occurrence and concentration of phthalic acid esters in nine stations (27 sediment samples) in this wetland alongside their relationship with physical and chemical properties of the sediments were studied. The samples were extracted by using ultrasound assisted solvent extraction and analyzed for six major phthalates using a gas chromatograph-mass spectrometer. Results of laboratory analyses showed that concentrations of six major phthalic acid esters in the Anzali sediments ranged from 4.18 to 20.71 mg kg(-1) with an average of 7.65 mg kg(-1). In addition, it was found that the site of Sorkhankol was heavily polluted by phthalic acid esters especially di-(2-ethylhexyl) phthalate (20.71 mg/kg dw). The concentrations of dimethyl phthalate and diethyl phthalate) were lower than the limit of detection of the GC-MS instrument. Di-(2-ethylhexyl) phthalate and di-n-butyl phthalate were the dominant phthalic acid esters present in all examined sediments. Generally, the mean concentrations of di-(2-ethylhexyl) phthalate was well above the United States Environmental Protection Agency sediment guideline value and environmental risk limits. Furthermore, investigation of sediment chemical properties revealed that the concentrations of di-n-butyl phthalate have significant linear positive correlations with sediments organic matters.