Direct Determination of Trace Hormones in Drinking Water by Large Volume Injection using the LCMS-8050 Triple Quadrupole Mass Spectrometer

Endocrine disrupting compounds enter the aquatic environment primarily through the discharge of treated and raw sewage and are detrimental to aquatic organisms even at sub-nanogram per litre levels. In the majority of North American and European cities wastewater treatment plant effluent is indirectly re-used, through discharge into rivers which are also a source of drinking water. Consequently, there is the possibility that trace amounts may enter into drinking water even after special treatment processes. Several hormones (estrone, estriol, 17-β-estradiol, equilin, androstenedione, testosterone and 17-αEthynylestradiol) are routinely monitored by the US EPA in drinking water as part of the Unregulated Contaminant Monitoring program (UCMR3). In this study, the LCMS-8050 triple quadrupole mass spectrometer was used for the highly selective and sensitive detection of hormones in water to meet the requirements of UCMR3. This direct high volume injection method of analysis avoids the disadvantages associated with extracting samples using SPE as is commonly performed. Ammonium fluoride as an aqueous mobile phase additive was found to significantly improve response for all studied hormones in comparison to ammonium hydroxide. The excellent sensitivity of the final method provided detection limits ranging from 0.005 ng/L (testosterone) to 0.330 ng/L (17-α-ethynylestradiol).