Determination of estrogenic nonylphenol and bisphenol A in river water by solid-phase extraction and gas chromatography-mass spectrometry

A simple and sensitive method is presented for the analysis of nonylphenol (NP) and bisphenol A (BPA), two well known hormonally active agents (HAAs), in the samples of river water. The method involves extraction of the sample by a graphitized carbon black (GCB) solid-phase extraction, and determination by an ion-trap gas chromatography-mass spectrometry (GC-MS). The large-volume injection technique provides high precision and sensitivity for NP and BPA, to quantitation at < 0.05 <mu>g/L in 200 mL of water samples. Recovery of NP and BPA in spiked water samples ranged from 80% to 85%. Relative standard deviations (RSD) of replicate analyses ranged from 1.6% to 6.9%. The concentrations of NP in rivers were in the range between 0.4 to 2.4 mug/L, which were below the threshold concentration (10 mug/L) for vitellogenin induction in fish, but 78% of water samples from five rivers exceeded the predicted-no-effect concentration (PNEC) of 0.7 mug/L as proposed recently. The concentrations of BPA ranged from < 0.05 <mu>g/L to 3.0 mug/L, which all were below the PNEC of 64 mug/L.