Measuring Free, Conjugated, and Halogenated Estrogens in Secondary Treated Wastewater Effluent

Abstract

Steroidal estrogens are potent endocrine-disrupting chemicals that enter natural waters through the discharge of treated and raw sewage. Because estrogens are detrimental to aquatic organisms at sub-nanogram per liter concentrations, many studies have measured so-called "free" estrogen concentrations in wastewater effluents, rivers, and lakes. Other forms of estrogens are also of potential concern because conjugated estrogens can be easily converted to potent free estrogens by bacteria in wastewater treatment plants and receiving waters and halogenated estrogens are likely produced during wastewater disinfection. However, to the best of our knowledge, no studies have concurrently characterized free, conjugated, and halogenated estrogens. We have developed a method that is capable of simultaneously quantifying free, conjugated, and halogenated estrogens in treated wastewater effluent, in which detection limits were 0.13-1.3 ng L(-1) (free), 0.11-1.0 ng L(-1) (conjugated), and 0.18-18 ng L(-1) (halogenated). An aqueous phase additive, ammonium fluoride, was used to increase the electrospray (negative mode) ionization efficiency of free and halogenated estrogens by factors of 20 and 2.6, respectively. The method was validated using treated effluent from the greater Boston metropolitan area, where conjugated and halogenated estrogens made up 60-70% of the steroidal estrogen load on a molar basis.

Simultaneous measurement of free and conjugated estrogens in surface water using capillary liquid chromatography tandem mass spectrometry

“…10,74 Due to the great difference between lipophilic free estrogens and hydrophilic estrogen conjugates, and highly broad range of polar and nonpolar property of them, reverse-phased absorbents were suitable for retaining targeted compounds due to the polymeric fillings. 71 An Oasis HLB, Strata-X, Supel™-Select HLB were selected and studied further by extracting 10 mL spiked Milli-Q water at concentration of 1 µg L −1 . The result (Table 3) showed that Oasis HLB achieved satisfactory recoveries (89.3%-102.8%) for chosen compounds reproducibility was with relative standard deviation (RSD) value less than 9.72%, having better performance than Stata-X (65.8%-110.3%) and Supel™-Select HLB cartridges (74.5%-103.3%).…”

“…It was consistent with the chromatographic profiles reported in previous methods for measurement of both free and conjugated estrogens, wherein up to 45 min gradient was used for each injection. 28,63,65,[71][72][73] Though the C18 column did not allow complete baseline separation of the chosen compounds, especially for E2-DMIS and EE2-DMIS as well as E1-3S and E2-3S, they could be differentiated by mass spectrometric signal by the different m/z values of respective precursor ion and additionally by their specific fragmentation pathway upon MS 2 fragmentation of their precursor ions.…”

“…[15][16][17] In comparison, free estrogens including endogenous compounds estrone (E1), 17β-estradiol (E2), and estriol (E3) and synthetically exogenous endocrine disruptors such as 17α-ethinylestradiol (EE2), are less polar and more hydrophobic, rendering them more bioactive and potentially bioaccumulative. 18 However, conjugated estrogens are subsequently readily hydrolysed to free forms by enzymes (e.g. arylsulfatase and glucuronidase) produced from microorganisms, bringing on potential higher risk after undergoing the reactivation process.…”

Environmental metabolomics: Analytical strategies

“…The standard appears as a peak at 9.17 min in the intracellular extract ( Figure S6B), but in this case is entirely absent from the extracellular extract ( Figure S6D). Matrix effects are a potential concern when calibration solutions made in solvent are applied to the quantitation of analytes in a seawater or other complex matrix (Griffith et al, 2014). As noted above, we have investigated the significance of matrix effects in our targeted metabolomics method but full discussion of these results are beyond the scope of this paper (Johnson, Kido Soule, & Kujawinski, unpublished).…”

Polydopamine‐coated cotton fibers as the adsorbent for in‐tube solid‐phase microextraction

“…SPE was most common sample preparation method for the determination of estrogens . Aminopropyl‐silica , C 18 ‐bonded silica , cross‐linked styrene and divinylbenzene were used as SPE adsorbents. Large amount of organic solvent was necessary for SPE.…”