Stability, preservation, and quantification of hormones and estrogenic and androgenic activities in surface water runoff

Impact of sample acidification and extract storage on hormone receptor-mediated and oxidative stress activities in wastewater

An underemphasized aspect of sampling strategies in effect-based in vitro testing is to determine suitable collection and preparation techniques. In the current study, the impact of sample acidification on bioactivities was assessed using in vitro bioassays for hormone receptor-mediated effects (estrogen receptor [ER] and androgen receptor [AR]) and the oxidative stress response (Nrf2 activity). Sampling was conducted at a recently upgraded Swedish wastewater treatment plant. Future plans for the treated wastewater include reuse for irrigation or as a potential drinking water source. In the AR and Nrf2 assays, acidification decreased bioactivities in the wastewater influent sample extracts, whereas acidification increased bioactivities following further treatment (disc filtration). In the ER assay, acidification had no impact on the observed bioactivities in the sample extracts. A secondary objective of the study was to assess the stability of the sample extracts over time. Lower activities were detected in the ER and AR assays in all extracts after storage for approximately 1 year. Nrf2 activities did not decrease over time, but rather increased in some of the acidified sample extracts. Overall, the findings suggest that sampling strategies involving acidification may need to be tailored depending on the selected bioassay(s) and the type of wastewater treatments being assessed.

Adaptation of the o-DGT for the sampling of 12 hormones: calibration, performance evaluation, and recommendation

This work highlights the methodology for the development of diffusive gradients in thin films (o-DGT) through its adaptation for 12 natural and synthetic hormones belonging to three different families (estrogens, progestins, and androgens). A reliable strategy must be applied during o-DGT lab adaptation to avoid issues related to the analysis (i.e., presence of matrix effects in grab or passive samples) but also to the o-DGT configuration (i.e., undesirable sorption or desorption, lack of performance with insufficient elution or unreliable diffusion coefficient). To avoid analytical issues due to the presence of salts in grab samples, CaCl₂ exposure solutions must be used on a lab-scale development to monitor the hormone concentration. The selected o-DGT was composed of an Oasis® HLB binding gel and a diffusive gel in agarose because they provided better performance than polyacrylamide gels (i.e., higher elution factors and more repeatable diffusion coefficients). The elution factors of the binding gel were then from 0.79 ± 0.13 to 1.04 ± 0.13 (RSD < 15%) and the diffusion coefficients at 25 °C were from 4.07 ± 0.24 to 5.49 ± 0.28 × 10^-6 cm² s^-1 (RSD < 9%). A laboratory exposure to a synthetic solution was performed to check the consistency with the DGT quantification model validating the calibration parameters for all hormones (except 17α-ethinylestradiol with a bias of 40%). Therefore, the o-DGT configuration is suitable for sampling hormones in the natural environment with LOQ_DGT ranging from 0.3 to 6.6 ng L^-1.

Assessment of automated off-line solid-phase extraction LC-MS/MS to monitor EPA priority endocrine disruptors in tap water, surface water, and wastewater

EPA method 539.1 recently introduced an expanded list of priority endocrine-disrupting compounds (EDCs), some of which were also included in the Unregulated Contaminant Monitoring Rule 3 (UCMR3). Though standardized methods are available for drinking water, analysis of steroid hormones and bisphenol A (BPA) at the ultra-trace level remains challenging. This study set out to evaluate the suitability of automated off-line solid-phase extraction (SPE) liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) for the determination of EPA-priority EDCs in environmental water matrixes (tap water, surface water, and wastewater influents and effluents). The target molecules included 14 steroid hormones (altrenogest, androstenedione, equilenin, equilin, α-estradiol, β-estradiol, estriol, estrone, ethinylestradiol, levonorgestrel, medroxyprogesterone, norethindrone, progesterone, testosterone) and BPA. Factors that may influence the analytical performance were assessed. This involved, for instance, testing combinations of SPE materials from different brands and protocol variations. Several materials presented absolute extraction efficiencies in acceptable ranges. Initial sample pH, nature of reconstitution medium, and mobile phase salt concentration were among the potential factors affecting analyte signal. Storage conditions (different preservative agents) possibly exerted the strongest influence, in agreement with the literature. Limits of detection were in the range of 0.03-0.5 ng/L in drinking water, 0.1-0.5 ng/L in surface water, and 0.16-1 ng/L in wastewater. Method validation also involved testing linearity, accuracy, and precision in reagent water and matrix-matched extracted calibrants. The method was applied to field-collected water samples in Eastern Canada. Summed EDC concentrations remained low in tap water (<LOQ-0.92 ng/L), while higher detection frequencies and contamination levels were reported in riverine surface waters (2.6-37 ng/L) and municipal wastewaters (10-424 ng/L).

Development and implementation of an analytical procedure for the quantification of natural and synthetic steroid hormones in whole surface waters

Natural and synthetic steroid hormones are chronically released into aquatic spheres. Whereas knowledge on their combined mode of action and the cocktail effect are needed, only few multi-class methods address the challenge of their trace quantification in surface waters. The current study describes a sensitive multi-residue analytical strategy aiming to quantify 23 steroid hormones belonging to androgens, estrogens, glucocorticoids and progestogens in whole surface waters. The procedure relies on a two-step solid-phase extraction followed by an ultra-performance liquid chromatography separation coupled to tandem mass spectrometry detection (UPLC-MS/MS). Isotope dilution was implemented when possible in order to ensure the reliability of the measurement. The procedure was optimized toward the reliable quantification of the 23 target compounds at the predicted no-effect concentrations when existing or below the ng L^-1 level. Satisfactory absolute global recoveries ≥ 77% were obtained for almost all compounds (21 out of 23) in intermediate precision conditions. Measurement errors were comprised between -27% and +17% for the great majority of compounds (21 out of 23) with standard deviations < 20% in intermediate precision conditions. Despite signal suppression was observed in water samples, satisfactory limits of quantification were achieved, ranging from 0.035 ng L^-1 for 17alpha-ethinylestradiol to 1 ng L^-1 for 6beta-hydroxycortisol and 6beta-hydroxydexamethasone. Abiotic stability was demonstrated for the great majority of target compounds (22 out of 23) in reference water samples stored at 4 ± 3 °C during 48 h, driving our sampling strategy. To demonstrate its fitness for purpose, the procedure was implemented in a preliminary monitoring survey of Belgian surface waters. As a result, 6 out of 23 target compounds were detected or quantified, showing a contamination by some estrogens and glucocorticoids at levels ranging from 0.1 to 0.9 ng L^-1.

Occurrence of estrogens, androgens and progestogens and estrogenic activity in surface water runoff from beef and dairy manure amended crop fields

Hormone contamination of aquatic systems has been shown to cause reproductive impairment of aquatic organisms. To assess to what extent beef and dairy farms represent a source of hormones to the aquatic environment, surface water runoff samples from three beef and dairy farms that utilize best manure management practices were evaluated for hormone concentrations (estrogens, androgens, progestogens) and estrogenic activity. Runoff was collected from weirs at the edge of each of six study fields from March 2008 to March 2010 and was analyzed for hormone concentrations using liquid chromatography with tandem mass spectrometry and for estrogenic activity using the E-screen bioassay. The majority of runoff events occurred in February and March when the soil was frozen. Progesterone and 4-androstenedione were the most frequently detected hormones (63% and 50%, respectively) and occurred at event loads up to 49,000 μg/ha and 26,000 μg/ha, respectively. Progesterone, 4-androstenedione, 17α-estradiol had the highest event load concentrations and were found at the field that sustained dairy cattle grazing during the winter and were likely due to application of excreta on frozen soil. The high progesterone event loads could lead to concentrations in receiving streams that exceed the lowest observable effects concentrations for fish. There was a consistent association with the elevated zearalenone presence and corn production. The synthetic hormones, 17α-trenbolone and 17β-trenbolone, were not detected in runoff from the beef farm that utilized trenbolone acetate implants, which is likely due to their short half lives. Estrogenic activity in runoff samples ranged from 0.09 to 133 ng/L estradiol equivalents, with 39% of runoff events exceeding the 2 ng/L predicted-no-effect-concentration for fish. These results indicate that grazing cattle and application of manure to frozen fields present the greatest risk to elevated hormones in runoff and that progesterone is the primary hormone of concern from beef and dairy operations.

The Fate of Synthetic and Endogenous Hormones Used in the US Beef and Dairy Industries and the Potential for Human Exposure

PURPOSE OF REVIEW

Growth-enhancing chemicals used by the beef and dairy industries may be bioavailable to humans via milk, meat, and other environmental matrices. This review evaluates the potential for environmental transport and bioavailability of the active chemical to humans.

RECENT FINDINGS

Bovine somatostatin is detectable in milk; however, there is no evidence that the protein persists in the environment nor that it is active in humans. In contrast, steroids are transported through milk and meat to humans where they may exert biological activity. Furthermore, environmental matrices such as raw water and dust may also allow for the environmental transport and bioavailability of steroids to humans. Endogenous and exogenous steroids can be found in the meat, milk, and waste materials produced by cattle. While the concentrations may be low, exposure to these matrices, most notably dairy products made with whole milk, can be a source of exogenous steroids to humans.

Influence of Acidification on the Partitioning of Steroid Hormones among Filtrate, Filter Media, and Retained Particulate Matter

Hormone contamination of aquatic systems has been shown to have deleterious effects on aquatic biota. However, the assessment of hormone contamination of aquatic environments requires a quantitative evaluation of the potential effects of sample preservation on hormone concentrations. This study investigated the influence of acidification (pH 2) of surface water samples on the partitioning of hormones among filtrate, filter media, and filter-retained particulate matter. Hormones were spiked into unpreserved and sulfuric acid-preserved ultrapure water and surface water runoff samples. The samples were filtered, and hormones were extracted from the filter and filtrate and analyzed by high-performance liquid chromatography. Acidification did not influence the partitioning of hormones onto the filter media. For the majority of the hormones investigated in this study, the partitioning of hormones to the filter-retained particulate matter was not influenced by acidification. Acidification increased the partitioning of progesterone and melengestrol acetate onto the retained particulate matter (about 25% for both analytes). Incorporation of an isotopically labeled internal standard (ISTD) for progesterone accounted for the loss of progesterone to the filter-retained particulates and resulted in accurate concentrations of progesterone in the filtrate. The incorporation of an ISTD for melengestrol acetate, however, was unable to account for the loss of melengestrol acetate to the retained particulates and resulted in underestimations of melengestrol acetate in the filtrate. Our results indicate that the analysis of melengestrol acetate in acid preserved surface runoff samples should be conducted on the filter-retained particulates as well as the filtrate.

Effects of androstenedione exposure on fathead minnow (Pimephales promelas) reproduction and embryonic development

High concentrations (300 ng/L) of androstenedione (A4) were identified in snowmelt runoff from fields fertilized with manure from livestock feeding operations in Wisconsin, USA. In fishes, A4 is an active androgen and substrate for biosynthesis of functional androgens (e.g., testosterone and 11-ketotestosterone) and estrogens (e.g., estradiol-17β). Thus, A4 has the potential to be a powerful endocrine disruptor. This hypothesis was tested by exposing reproductively mature fathead minnows to 0.0 ng/L, 4.5 ng/L, 74 ng/L, and 700 ng/L A4 for 26 d in a flow-through system. Various reproductive endpoints were measured including fecundity, fertilization success, secondary sexual characteristics, gonadosomatic index (GSI), and hepatic vitellogenin messenger RNA (mRNA) expression. In addition, fertilized embryos from the reproduction assay were used in an embryonic development assay to assess A4 effects on development and hatchability. In males, A4 significantly increased Vtg mRNA expression (estrogenic effect), significantly reduced GSI, and had no effect on tubercle expression (p = 0.067). In females, A4 induced tubercle development (androgenic effect) with no effects on GSI. Fecundity was not significantly impacted. Exposure to A4 had no effect on fertilization, embryonic development, or hatchability. These data indicate that exogenous A4, at environmentally relevant concentrations, can significantly modulate the reproductive physiology of the fathead minnows in a sex-specific manner and that A4 should be monitored as an endocrine disruptor.

Survey regarding the occurrence of selected organic micropollutants in the groundwaters of overseas departments

To collect a complete dataset regarding the occurrence of organic substances in groundwater, this study presents the examination of 66 organic contaminants in the groundwater of overseas departments, including pesticides, pharmaceutical compounds, hormones and some industrial substances. The selective and sensitive analytical methods are described. These techniques begin with solid-phase extraction (SPE) followed by analysis using liquid chromatography-tandem mass spectrometry (LC-MS/MS) and gas chromatography-mass spectrometry (GC-ToF-MS). The paper summarises the analytical results from 40 sampling points collected during two campaigns in Guadeloupe, Martinique, Reunion, Mayotte and Guiana, representing 80 samples. Of the 66 target substances, 36 were determined at least once. Among the most frequently detected are bisphenol A (frequency, 96%; max., 7,400 ng/L), caffeine (frequency, 91%; max., 1,240 ng/L), pentachlorophenol (frequency, 55%; max., 418 ng/L), and carbamazepine (frequency, 56%; max., 22 ng/L). The results do not put in evidence that the origin of the sample or climatic characteristics of these regions influence the dilution and release of micropollutants.

Transcriptional and physiological responses induced by binary mixtures of drospirenone and progesterone in zebrafish (Danio rerio)

Drospirenone (DRS) is a synthetic progestin increasingly used in oral contraceptives with similar effects to progesterone (P4). Wild fish are exposed to DRS and P4 through wastewater. However, the effects of DRS on fish, both as an individual compound and in mixtures, have not been extensively studied. Therefore, in this study, global gene expression profiles of ovary and brain of female zebrafish (Danio rerio) were characterized after exposure to 55, 553, and 5442 ng/L DRS for 14 days. The effects were then compared to the observed responses after exposure to mixtures of DRS and P4 (DRS+P4: 27 + 0.8, 277 + 8 and 3118 + 123 ng/L). Transcriptomics findings were related to the changes in vitellogenin protein concentrations in the blood, morphology, and histology of gonads. Multivariate analysis indicated tissue-, dose-, and treatment-dependent expression profiles. Genes involved in steroid hormone receptor activity and circadian rhythm were enriched in DRS and mixture groups, among other pathways. In mixtures, the magnitude of response was dose- and transcript-dependent, both at the molecular and physiological levels. Effects of DRS and P4 were additive for most of the investigated parameters and occurred at environmentally relevant concentrations. They may translate to adverse reproductive effects in fish.

Progesterone alters global transcription profiles at environmental concentrations in brain and ovary of female zebrafish (Danio rerio)

Progesterone (P4) is a natural steroid hormone excreted by humans and animals. Noncomplete degradation in treatment plants result in levels in the ng/L range in surface waters. Very little is known of the effects on fish at such concentrations. Here we determine the global expression profile in the brain and ovary of female zebrafish exposed for 14 days to 3.5, 33 and 306 ng/L P4 to elucidate molecular effects. For validation selected transcripts were determined by RT-qPCR. In the brain, 54 and 255 transcripts were altered at 3.5 and 306 ng/L, respectively. Genes related to circadian rhythm (nr1d2b, per1b), cell cycle and reproduction (cdc20, ccnb1) were down-regulated. In the ovary, transcriptional changes occurred in 200, 84 and 196 genes at 3.5, 33 and 306 ng/L, respectively. The genes belong to different pathways including cardiac hypertrophy, cell cycle and its regulation. P4 slightly influenced oocyte maturation as revealed by histology of the ovaries. In the liver, vtg1 was down-regulated at all concentrations and VTG protein at 306 ng/L in the blood. The data show molecular effects and the modes of action of P4 at environmental concentrations. Ultimately they may translate to adverse effects on reproduction.

Effects of progesterone on reproduction and embryonic development in the fathead minnow (Pimephales promelas)

High concentrations (375 ng/L) of the steroid hormone progesterone (P4) were measured in snowmelt runoff associated with large livestock-feeding operations in Wisconsin. To gain insight into the potential endocrine-disrupting effects of P4 in fish, experiments were conducted to evaluate the effects of short-term exposure to environmentally relevant concentrations of P4 on reproduction and embryonic development in the fathead minnow (Pimephales promelas). For the reproduction assay, groups of reproductively mature fish were exposed for 21 d to nominal concentrations of 0, 10, 100, and 1,000 ng/L P4 in a flow-through system, and various key reproductive endpoints (e.g., egg number, fertilization success) were quantified throughout the exposure period. The embryonic development assay consisted of incubating fathead minnow eggs in static culture to quantify the effects of P4 on early development and hatching success. Progesterone caused dose-dependent decreases in fecundity and fertility and significantly reduced gonadosomatic index and vitellogenin gene expression in females. There were no effects of P4 on early embryonic development or hatching success. Progesterone may be a significant endocrine-disrupting chemical in fish.

Fate of 4-nonylphenol and 17β-estradiol in the Redwood River of Minnesota

The majority of previous research investigating the fate of endocrine-disrupting compounds has focused on single processes generally in controlled laboratory experiments, and limited studies have directly evaluated their fate and transport in rivers. This study evaluated the fate and transport of 4-nonylphenol, 17β-estradiol, and estrone in a 10-km reach of the Redwood River in southwestern Minnesota. The same parcel of water was sampled as it moved downstream, integrating chemical transformation and hydrologic processes. The conservative tracer bromide was used to track the parcel of water being sampled, and the change in mass of the target compounds relative to bromide was determined at two locations downstream from a wastewater treatment plant effluent outfall. In-stream attenuation coefficients (k(stream)) were calculated by assuming first-order kinetics (negative values correspond to attenuation, whereas positive values indicate production). Attenuation of 17β-estradiol (k(stream) = -3.2 ± 1.0 day(-1)) was attributed primarily due to sorption and biodegradation by the stream biofilm and bed sediments. Estrone (k(stream) = 0.6 ± 0.8 day(-1)) and 4-nonylphenol (k(stream) = 1.4 ± 1.9 day(-1)) were produced in the evaluated 10-km reach, likely due to biochemical transformation from parent compounds (17β-estradiol, 4-nonylphenolpolyethoxylates, and 4-nonyphenolpolyethoxycarboxylates). Despite attenuation, these compounds were transported kilometers downstream, and thus additive concentrations from multiple sources and transformation of parent compounds into degradates having estrogenic activity can explain their environmental persistence and widespread observations of biological disruption in surface waters.

Effects of watershed densities of animal feeding operations on nutrient concentrations and estrogenic activity in agricultural streams

Application of manures from animal feeding operations (AFOs) as fertilizer on agricultural land can introduce nutrients and hormones (e.g. estrogens) to streams. A landscape-scale study was conducted in the Shenandoah River watershed (Virginia, USA) in order to assess the relationship between densities of AFOs in watersheds of agricultural streams and in-stream nutrient concentrations and estrogenic activity. The effect of wastewater treatment plants (WWTPs) on nutrients and estrogenic activity was also evaluated. During periods of high and low flow, dissolved inorganic nitrogen (DIN) and orthophosphate (PO(4)-P) concentrations were analyzed and estrogens/estrogenic compounds were extracted and quantified as17β-estradiol equivalents (E2Eq) using a bioluminescent yeast estrogen screen. Estrogenic activity was measurable in the majority of collected samples, and 20% had E2Eq concentrations >1 ng/L. Relatively high concentrations of DIN (>1000 μg/L) were also frequently detected. During all sampling periods, there were strong relationships between watershed densities of AFOs and in-stream concentrations of DIN (R(2) = 0.56-0.81) and E2Eq (R(2) = 0.39-0.75). Relationships between watershed densities of AFOs and PO(4)-P were weaker, but were also significant (R(2) = 0.27-0.57). When combined with the effect of watershed AFO density, streams receiving WWTP effluent had higher concentrations of PO(4)-P than streams without WWTP discharges, and PO(4)-P was the only analyte with a consistent relationship to WWTPs. The results of this study suggest that as the watershed density of AFOs increases, there is a proportional increase in the potential for nonpoint source pollution of agricultural streams and their receiving waters by nutrients, particularly DIN, and compounds that can cause endocrine disruption in aquatic organisms.

Fate of endogenous steroid hormones in steer feedlots under simulated rainfall-induced runoff

Steroid hormones pose potential risks to fish and other aquatic organisms at extremely low concentrations. To assess the factors affecting the release of endogenous estrogenic and androgenic steroids from feedlots during rainfall, runoff, and soil samples were collected after simulated rainfall on a 14-steer feedlot under different rainfall rates and aging periods and analyzed for six steroid hormones. While only 17α-estradiol, testosterone, and progesterone were detected in fresh manure, 17β-estradiol, estrone, and androstenedione were present in the surficial soil after two weeks. In the feedlot surficial soil, concentrations of 17α-estradiol decreased by approximately 25% accompanied by an equivalent increase in estrone and 17β-estradiol. Aging of the feedlot soils for an additional 7 days had no effect on estrogen and testosterone concentrations, but androstenedione concentrations decreased substantially, and progesterone concentrations increased. Androstenedione and progesterone concentrations in the surficial soil were much higher than could be accounted for by excretion or conversion from testosterone, suggesting that other potential precursors, such as sterols, were converted after excretion. The concentration of androgens and progesterone in the soil were approximately 85% lower after simulated rainfall, but the estrogen concentrations remained approximately constant. The decreased masses could not be accounted for by runoff, suggesting the possibility of rapid microbial transformation upon wetting. All six steroids in the runoff, with the exception of 17β-estradiol, were detected in both the filtered and particle-associated phases at concentrations well above thresholds for biological responses. Runoff from the aged plots contained less 17α-estradiol and testosterone, but more estrone, androstenedione, and progesterone relative to the runoff from the unaged plots, and most of the steroids had a lower particle-associated fraction.