In Vitro and In Vivo Assessment of Aqueously Extractable Estrogens in Poultry Manure after Pilot-scale Composting

Effect comparisons of different conditioners and microbial agents on the degradation of estrogens during dairy manure composting

To investigate the degradation efficiency of conditioners and commercial microbial agents on estrogens (E1, 17α-E2, 17β-E2, E3, EE2, and DES) in the composting process of dairy manure, seven different treatments (RHB-BF, OSP-BF, SD-BF, MR-BF, MR-FS, MR-EM, and MR-CK) under forced ventilation conditions were composted and monitored regularly for 30 days. The results indicated that the removal rates of estrogens in seven treatments ranged from 95.35% to 99.63%, meanwhile the degradation effect of the composting process on 17β-Estradiol equivalent (EEQ) was evaluated, and the removal rate of ΣEEQ ranged from 96.42% to 99.72%. With the combined addition of rice husk biochar (RHB) or oyster shell powder (OSP) and bio-bacterial fertilizer starter cultures (BF), namely RHB-BF and OSP-BF obviously promoted the rapid degradation of estrogens. 17β-E2 was completely degraded on the fifth day of composting in OSP-BF. Microbial agents have some promotional effect and enhances the microbial degradation of synthetic estrogen (EE2, DES). According to the results of RDA, pH and EC were the main environmental factors affecting on the composition and succession of estrogen-related degrading bacteria in composting system. As predominant estrogens-degrading genera, Acinetobacter, Bacillus, and Pseudomonas effected obviously on the change of estrogens contents. The research results provide a practical reference for effective composting of dairy manure to enhancing estrogens removal and decreasing ecological risk.

Mineralization and Biotransformation of Estrone in Simulated Poultry Litter and Cow Manure Runoff Water

Application of animal manure on agricultural lands is one of the main sources of estrogen contamination in the environment. Poultry and cow manure contain free and conjugated forms of the natural estrogens (e.g., estrone [E1] and estradiol [E2]) that can enter surface waters during runoff events. Estrone has been identified as the major form of estrogen in the environment; therefore, this study is focused on the evaluation of the degree of mineralization and fate of E1 in a simulated poultry litter and cow manure runoff water. A time-course study was conducted using simulated runoff water that consisted of 0.5 mg cow manure or poultry litter dissolved in 1 L of water spiked with radiolabeled E1 (C-E1). Samples were analyzed for estrogen concentrations at Day 0, 0.5, 1, 2, 3, 5, and 7 using liquid chromatography with tandem mass spectrometry. In the poultry litter simulated runoff water, E1 was biotransformed to 17β-estrone-3-sulfate (E1-3S) but was eventually mineralized to CO; a total E1 mineralization of 92.2% occurred after 7 d of aerobic incubation. In contrast, the concentrations of E1 and other forms of endogenous estrogens detected in the cow manure simulated runoff water, such as E1-3S, 17α-estradiol (α-E2), and 17β-estradiol (β-E2), remained relatively constant and persisted over the 7 d of aerobic incubation. Results of this study demonstrate the differences in the fate of estrone in the simulated poultry litter and cow manure runoff water, highlighting the ability of the endogenous microbial community from poultry litter to mineralize estrogens to CO.

Sorption of 17β-estradiol to the dissolved organic matter from animal wastes: effects of composting and the role of fulvic acid-like aggregates

Steroid estrogens, such as 17β-estradiol (E2), in animal manure pose a potential threat to the aquatic environment. The transport and estrogenicity of estrogens influence the sorption of estrogens to dissolved organic matter (DOM) in animal manure, and composting treatment alters the structure and composition of the manure. The objectives of the present study were to identify the contribution of the molecular composition of DOM of composted manure to the sorption of E2 and then elucidate the dominant mechanisms involved in the interaction of E2 with manure-derived DOM. The excitation-emission matrix (EEM) spectra and atomic force microscopy (AFM) showed that composting significantly altered the chemical composition and structure of DOM. A decrease in the atomic ratios of oxygen (O)/carbon (C) occurred in conjunction with the formation of DOM aggregates in the composted manure, indicating that the hydrophilicity and polarity of the DOM decreased after composting. Composting increased the sorption coefficients (K_DOC-E2) for E2 to DOM, and K_DOC-E2 was positively correlated with the proportion of the fulvic acid (FA)-like fraction and molecular weight (MW) fractions of the DOM (range of 1.0 × 10³-7.0 × 10³ Da and 7.0 × 10³-1.4 × 10⁴ Da). Specifically, E2 showed a tendency for sorption to medium-sized FA-like molecules of DOM aggregates in composted manure. Hydrophobic forces and π-π binding appeared to be the main mechanisms underlying the aforementioned interaction.

Exposure effects of levonorgestrel on oogenesis in the fathead minnow (Pimephales promelas)

The synthetic progestin levonorgestrel is commonly utilized in human oral contraceptives. It enters the environment as a component of wastewater treatment plant effluent, and has been measured at low ng/L concentrations in surface waters. It has been shown to activate fish androgen receptors, causing the physical masculinization of females, changes in reproductive behavior, and decreases in fecundity. In the present study, the effects of levonorgestrel exposure on early-stage oogenesis in the fathead minnow (Pimephales promelas) was examined. Adult females were exposed to 0, 10, or 100 ng/L levonorgestrel for 14 d using a flow-through exposure system. The ovaries from each female were then removed via dissection and weighed for gonadosomatic index (GSI) calculations, and oocytes from one lobe preserved in Serra's fixative. Total numbers of late-stage vitellogenic oocytes exhibiting a germinal vesicle were then quantified. In a second exposure, blood plasma samples were collected from adult females and analyzed for vitellogenin concentrations using enzyme-linked immunosorbent assay. Females exposed to both concentrations of levonorgestrel developed male secondary sexual characteristics in a dose-dependent manner, and ovaries contained significantly fewer late stage oocytes. Exposure to 100 ng/L of levonorgestrel resulted in decreased GSI and blood plasma vitellogenin concentrations. The results suggest that female exposure to levonorgestrel alone may have profound effects on reproduction in progestin-contaminated environments. Environ Toxicol Chem 2017;36:3299-3304. © 2017 SETAC.