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Walter J. Smolenski - One of the best experts on this subject based on the ideXlab platform.
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degradation and transformation of 17α Trenbolone in aerobic water sediment systems
Environmental Toxicology and Chemistry, 2017Co-Authors: Joseph A. Robinson, Jane P. Staveley, Walter J. Smolenski, Jon F. EricsonAbstract:Synovex® ONE is an extended-release implant containing the active ingredients estradiol benzoate and Trenbolone acetate for use in beef steers and heifers. Trenbolone acetate is rapidly hydrolyzed in cattle to form 17β-Trenbolone and its isomer, 17α-Trenbolone, which are further transformed to a secondary metabolite, trendione. As part of the environmental assessment for the use of Synovex ONE, data were generated to characterize the fate of 17α-Trenbolone, which is the principal metabolite found in cattle excreta, in the environment. A study was conducted to determine the degradation and transformation of [14 C]-17α-Trenbolone in 2 representative water-sediment systems under aerobic conditions. The same transformation products, 17β-Trenbolone and trendione, were formed, principally in the sediment phase, in both systems. From the production of these transformation products, the 50% disappearance time (DT50) values of 17β-Trenbolone and trendione were determined, along with the DT50 values of the parent compound and the total drug (17α-Trenbolone + 17β-Trenbolone + trendione). The DT50 values for the total system (aqueous and sediment phase) and for the total residues (17α-Trenbolone + 17β-Trenbolone + trendione) in the 2 systems were 34.7 d and 53.3 d, respectively. Environ Toxicol Chem 2017;36:630-635. © 2016 SETAC.
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sorption and desorption of 17α Trenbolone and trendione on five soils
Environmental Toxicology and Chemistry, 2017Co-Authors: Joseph A. Robinson, Jane P. Staveley, Walter J. SmolenskiAbstract:The metabolites 17α-Trenbolone and 17α-estradiol are principal metabolites in cattle excreta following the administration of Synovex® ONE, which contains Trenbolone acetate and estradiol benzoate. As part of the environmental assessment of the use of Synovex ONE, data were generated to characterize the fate of 17α-Trenbolone, and its metabolite trendione in the environment. Predictions of the fate and environmental concentrations of these hormones after land application require accurate estimates of the sorption of these compounds in soils. The sorption and desorption of 17α-Trenbolone and trendione were measured at 5 nominal concentrations in 5 soils from different geologic settings using a batch equilibrium technique following guideline 106 of the Organisation for Economic Co-operation and Development. Both the sorption and desorption of 17α-Trenbolone and trendione to soils were adequately described by the Freundlich sorption model and by linear partition coefficients. The mean sorption coefficients were 9.04 mL/g and 32.2 mL/g for 17α-Trenbolone and trendione, respectively. The corresponding mean Freundlich sorption exponents were 0.88 and 0.98, respectively. Sorption of 17α-Trenbolone and trendione was correlated principally with soil organic carbon. Average sorption coefficients normalized to soil organic carbon content (KOC ) were 460 mL/g and 1804 mL/g for 17α-Trenbolone and trendione, respectively. The mean desorption coefficients were 22.1 mL/g and 43.8 mL/g for 17α-Trenbolone and trendione, respectively. Calculated hysteresis coefficients based on the difference in the area between sorption and desorption isotherms indicated that sorption equilibrium was not fully reversible and hysteresis of desorption isotherms occurred for both 17α-Trenbolone and trendione. Environ Toxicol Chem 2017;36:613-620. © 2016 SETAC.
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Sorption and desorption of 17α‐Trenbolone and trendione on five soils
Environmental Toxicology and Chemistry, 2017Co-Authors: Joseph A. Robinson, Jane P. Staveley, Walter J. SmolenskiAbstract:The metabolites 17α-Trenbolone and 17α-estradiol are principal metabolites in cattle excreta following the administration of Synovex® ONE, which contains Trenbolone acetate and estradiol benzoate. As part of the environmental assessment of the use of Synovex ONE, data were generated to characterize the fate of 17α-Trenbolone, and its metabolite trendione in the environment. Predictions of the fate and environmental concentrations of these hormones after land application require accurate estimates of the sorption of these compounds in soils. The sorption and desorption of 17α-Trenbolone and trendione were measured at 5 nominal concentrations in 5 soils from different geologic settings using a batch equilibrium technique following guideline 106 of the Organisation for Economic Co-operation and Development. Both the sorption and desorption of 17α-Trenbolone and trendione to soils were adequately described by the Freundlich sorption model and by linear partition coefficients. The mean sorption coefficients were 9.04 mL/g and 32.2 mL/g for 17α-Trenbolone and trendione, respectively. The corresponding mean Freundlich sorption exponents were 0.88 and 0.98, respectively. Sorption of 17α-Trenbolone and trendione was correlated principally with soil organic carbon. Average sorption coefficients normalized to soil organic carbon content (KOC ) were 460 mL/g and 1804 mL/g for 17α-Trenbolone and trendione, respectively. The mean desorption coefficients were 22.1 mL/g and 43.8 mL/g for 17α-Trenbolone and trendione, respectively. Calculated hysteresis coefficients based on the difference in the area between sorption and desorption isotherms indicated that sorption equilibrium was not fully reversible and hysteresis of desorption isotherms occurred for both 17α-Trenbolone and trendione. Environ Toxicol Chem 2017;36:613-620. © 2016 SETAC.
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Degradation and transformation of 17α‐Trenbolone in aerobic water–sediment systems
Environmental Toxicology and Chemistry, 2016Co-Authors: Joseph A. Robinson, Jane P. Staveley, Walter J. Smolenski, Jon F. EricsonAbstract:Synovex® ONE is an extended-release implant containing the active ingredients estradiol benzoate and Trenbolone acetate for use in beef steers and heifers. Trenbolone acetate is rapidly hydrolyzed in cattle to form 17β-Trenbolone and its isomer, 17α-Trenbolone, which are further transformed to a secondary metabolite, trendione. As part of the environmental assessment for the use of Synovex ONE, data were generated to characterize the fate of 17α-Trenbolone, which is the principal metabolite found in cattle excreta, in the environment. A study was conducted to determine the degradation and transformation of [14 C]-17α-Trenbolone in 2 representative water-sediment systems under aerobic conditions. The same transformation products, 17β-Trenbolone and trendione, were formed, principally in the sediment phase, in both systems. From the production of these transformation products, the 50% disappearance time (DT50) values of 17β-Trenbolone and trendione were determined, along with the DT50 values of the parent compound and the total drug (17α-Trenbolone + 17β-Trenbolone + trendione). The DT50 values for the total system (aqueous and sediment phase) and for the total residues (17α-Trenbolone + 17β-Trenbolone + trendione) in the 2 systems were 34.7 d and 53.3 d, respectively. Environ Toxicol Chem 2017;36:630-635. © 2016 SETAC.
Joseph A. Robinson - One of the best experts on this subject based on the ideXlab platform.
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degradation and transformation of 17α Trenbolone in aerobic water sediment systems
Environmental Toxicology and Chemistry, 2017Co-Authors: Joseph A. Robinson, Jane P. Staveley, Walter J. Smolenski, Jon F. EricsonAbstract:Synovex® ONE is an extended-release implant containing the active ingredients estradiol benzoate and Trenbolone acetate for use in beef steers and heifers. Trenbolone acetate is rapidly hydrolyzed in cattle to form 17β-Trenbolone and its isomer, 17α-Trenbolone, which are further transformed to a secondary metabolite, trendione. As part of the environmental assessment for the use of Synovex ONE, data were generated to characterize the fate of 17α-Trenbolone, which is the principal metabolite found in cattle excreta, in the environment. A study was conducted to determine the degradation and transformation of [14 C]-17α-Trenbolone in 2 representative water-sediment systems under aerobic conditions. The same transformation products, 17β-Trenbolone and trendione, were formed, principally in the sediment phase, in both systems. From the production of these transformation products, the 50% disappearance time (DT50) values of 17β-Trenbolone and trendione were determined, along with the DT50 values of the parent compound and the total drug (17α-Trenbolone + 17β-Trenbolone + trendione). The DT50 values for the total system (aqueous and sediment phase) and for the total residues (17α-Trenbolone + 17β-Trenbolone + trendione) in the 2 systems were 34.7 d and 53.3 d, respectively. Environ Toxicol Chem 2017;36:630-635. © 2016 SETAC.
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sorption and desorption of 17α Trenbolone and trendione on five soils
Environmental Toxicology and Chemistry, 2017Co-Authors: Joseph A. Robinson, Jane P. Staveley, Walter J. SmolenskiAbstract:The metabolites 17α-Trenbolone and 17α-estradiol are principal metabolites in cattle excreta following the administration of Synovex® ONE, which contains Trenbolone acetate and estradiol benzoate. As part of the environmental assessment of the use of Synovex ONE, data were generated to characterize the fate of 17α-Trenbolone, and its metabolite trendione in the environment. Predictions of the fate and environmental concentrations of these hormones after land application require accurate estimates of the sorption of these compounds in soils. The sorption and desorption of 17α-Trenbolone and trendione were measured at 5 nominal concentrations in 5 soils from different geologic settings using a batch equilibrium technique following guideline 106 of the Organisation for Economic Co-operation and Development. Both the sorption and desorption of 17α-Trenbolone and trendione to soils were adequately described by the Freundlich sorption model and by linear partition coefficients. The mean sorption coefficients were 9.04 mL/g and 32.2 mL/g for 17α-Trenbolone and trendione, respectively. The corresponding mean Freundlich sorption exponents were 0.88 and 0.98, respectively. Sorption of 17α-Trenbolone and trendione was correlated principally with soil organic carbon. Average sorption coefficients normalized to soil organic carbon content (KOC ) were 460 mL/g and 1804 mL/g for 17α-Trenbolone and trendione, respectively. The mean desorption coefficients were 22.1 mL/g and 43.8 mL/g for 17α-Trenbolone and trendione, respectively. Calculated hysteresis coefficients based on the difference in the area between sorption and desorption isotherms indicated that sorption equilibrium was not fully reversible and hysteresis of desorption isotherms occurred for both 17α-Trenbolone and trendione. Environ Toxicol Chem 2017;36:613-620. © 2016 SETAC.
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Sorption and desorption of 17α‐Trenbolone and trendione on five soils
Environmental Toxicology and Chemistry, 2017Co-Authors: Joseph A. Robinson, Jane P. Staveley, Walter J. SmolenskiAbstract:The metabolites 17α-Trenbolone and 17α-estradiol are principal metabolites in cattle excreta following the administration of Synovex® ONE, which contains Trenbolone acetate and estradiol benzoate. As part of the environmental assessment of the use of Synovex ONE, data were generated to characterize the fate of 17α-Trenbolone, and its metabolite trendione in the environment. Predictions of the fate and environmental concentrations of these hormones after land application require accurate estimates of the sorption of these compounds in soils. The sorption and desorption of 17α-Trenbolone and trendione were measured at 5 nominal concentrations in 5 soils from different geologic settings using a batch equilibrium technique following guideline 106 of the Organisation for Economic Co-operation and Development. Both the sorption and desorption of 17α-Trenbolone and trendione to soils were adequately described by the Freundlich sorption model and by linear partition coefficients. The mean sorption coefficients were 9.04 mL/g and 32.2 mL/g for 17α-Trenbolone and trendione, respectively. The corresponding mean Freundlich sorption exponents were 0.88 and 0.98, respectively. Sorption of 17α-Trenbolone and trendione was correlated principally with soil organic carbon. Average sorption coefficients normalized to soil organic carbon content (KOC ) were 460 mL/g and 1804 mL/g for 17α-Trenbolone and trendione, respectively. The mean desorption coefficients were 22.1 mL/g and 43.8 mL/g for 17α-Trenbolone and trendione, respectively. Calculated hysteresis coefficients based on the difference in the area between sorption and desorption isotherms indicated that sorption equilibrium was not fully reversible and hysteresis of desorption isotherms occurred for both 17α-Trenbolone and trendione. Environ Toxicol Chem 2017;36:613-620. © 2016 SETAC.
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Reproductive effects on freshwater fish exposed to 17α-Trenbolone and 17α-estradiol.
Environmental Toxicology and Chemistry, 2016Co-Authors: Joseph A. Robinson, Jane P. Staveley, Lisa A. ConstantineAbstract:17α-Trenbolone and 17α-estradiol are principal metabolites in cattle excreta following the administration of Synovex® ONE, which contains Trenbolone acetate and estradiol benzoate. As part of the environmental assessment of the use of Synovex® ONE, data were generated to characterize the effects of 17α-Trenbolone and 17α-estradiol on the reproduction of freshwater fish. These substances are known endocrine disruptors, so the purpose of testing was not to clarify these properties but to identify concentrations representing population-relevant effects for use in risk characterization. The short-term reproduction assay was conducted with 17α-Trenbolone using the fathead minnow (Pimephales promelas) and the medaka (Oryzias latipes) and with 17α-estradiol using the fathead minnow. Adverse effects on the population-relevant endpoints of survival and fecundity were used to establish the no-observed-effect concentration (NOEC) and the lowest-observed-effect concentration (LOEC) for each study. For 17α-Trenbolone, adverse effects on fecundity of the fathead minnow occurred at 120 ng/L; this was the LOEC, and the NOEC was 35 ng/L. 17β-Trenbolone did not adversely affect survival and fecundity of medaka at the concentrations tested, resulting in a NOEC of 110 ng/L and a LOEC of >110 ng/L. 17α-Estradiol did not adversely impact survival and fecundity of the fathead minnow at the concentrations tested, resulting in a NOEC and LOEC of 250 ng/L and >250 ng/L, respectively. Environ Toxicol Chem 2017;36:636-644. © 2016 SETAC.
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Degradation and transformation of 17α‐Trenbolone in aerobic water–sediment systems
Environmental Toxicology and Chemistry, 2016Co-Authors: Joseph A. Robinson, Jane P. Staveley, Walter J. Smolenski, Jon F. EricsonAbstract:Synovex® ONE is an extended-release implant containing the active ingredients estradiol benzoate and Trenbolone acetate for use in beef steers and heifers. Trenbolone acetate is rapidly hydrolyzed in cattle to form 17β-Trenbolone and its isomer, 17α-Trenbolone, which are further transformed to a secondary metabolite, trendione. As part of the environmental assessment for the use of Synovex ONE, data were generated to characterize the fate of 17α-Trenbolone, which is the principal metabolite found in cattle excreta, in the environment. A study was conducted to determine the degradation and transformation of [14 C]-17α-Trenbolone in 2 representative water-sediment systems under aerobic conditions. The same transformation products, 17β-Trenbolone and trendione, were formed, principally in the sediment phase, in both systems. From the production of these transformation products, the 50% disappearance time (DT50) values of 17β-Trenbolone and trendione were determined, along with the DT50 values of the parent compound and the total drug (17α-Trenbolone + 17β-Trenbolone + trendione). The DT50 values for the total system (aqueous and sediment phase) and for the total residues (17α-Trenbolone + 17β-Trenbolone + trendione) in the 2 systems were 34.7 d and 53.3 d, respectively. Environ Toxicol Chem 2017;36:630-635. © 2016 SETAC.
Edward P. Kolodziej - One of the best experts on this subject based on the ideXlab platform.
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detection and quantification of metastable photoproducts of Trenbolone and altrenogest using liquid chromatography tandem mass spectrometry
Journal of Chromatography A, 2019Co-Authors: Philip T. Kenyon, David M. Cwiertny, Haoqi Zhao, Xingjian Yang, Edward P. KolodziejAbstract:Abstract Here, we developed a novel and sensitive method for the detection and quantification of metastable Trenbolone and altrenogest photoproducts in agricultural receiving waters based on solid phase extraction (SPE) and liquid chromatography-tandem mass spectrometry (LC–MS/MS). Primary method analytes were seven cycloaddition or photohydration transformation products of 17α-Trenbolone (17α-TBOH), 17β-Trenbolone (17β-TBOH), trendione (TBO), and altrenogest (ALT), which are key contributors to the fate and environmental risks of these steroidal pharmaceuticals. Because commercial analytical standards are not available, reference standards for photoproducts were generated from Trenbolone or ALT with a solar simulator (˜6 h, >10 half-lives). Efficient detection of metastable photoproducts required cold and pH neutral conditions, rapid sample processing, minimal sample storage, and consideration of cationic artifacts. Method detection limits (MDLs) were 0.034-0.40 ng L−1 for parent compounds and 0.16–2.1 ng L−1 for photoproducts, sufficient for their detection in agroecosystems. Matrix suppression was observed and corrected by internal standards, and relative recovery rates were near 100% for all analytes except for 12-OH-17α-TBOH (˜75% recovery). Intra-day variation was
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Detection and quantification of metastable photoproducts of Trenbolone and altrenogest using liquid chromatography–tandem mass spectrometry
Journal of Chromatography A, 2019Co-Authors: Philip T. Kenyon, David M. Cwiertny, Haoqi Zhao, Xingjian Yang, Edward P. KolodziejAbstract:Abstract Here, we developed a novel and sensitive method for the detection and quantification of metastable Trenbolone and altrenogest photoproducts in agricultural receiving waters based on solid phase extraction (SPE) and liquid chromatography-tandem mass spectrometry (LC–MS/MS). Primary method analytes were seven cycloaddition or photohydration transformation products of 17α-Trenbolone (17α-TBOH), 17β-Trenbolone (17β-TBOH), trendione (TBO), and altrenogest (ALT), which are key contributors to the fate and environmental risks of these steroidal pharmaceuticals. Because commercial analytical standards are not available, reference standards for photoproducts were generated from Trenbolone or ALT with a solar simulator (˜6 h, >10 half-lives). Efficient detection of metastable photoproducts required cold and pH neutral conditions, rapid sample processing, minimal sample storage, and consideration of cationic artifacts. Method detection limits (MDLs) were 0.034-0.40 ng L−1 for parent compounds and 0.16–2.1 ng L−1 for photoproducts, sufficient for their detection in agroecosystems. Matrix suppression was observed and corrected by internal standards, and relative recovery rates were near 100% for all analytes except for 12-OH-17α-TBOH (˜75% recovery). Intra-day variation was
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Rates and product identification for Trenbolone acetate metabolite biotransformation under aerobic conditions
Environmental Toxicology and Chemistry, 2015Co-Authors: Emily A. Cole, Samantha Mcbride, Kaitlin C. Kimbrough, Jaewoong Lee, Eric A. Marchand, David M. Cwiertny, Edward P. KolodziejAbstract:Trenbolone acetate metabolites are endocrine-active contaminants discharged into the aquatic environment in runoff from agricultural fields, rangelands, and concentrated animal feeding operations. To investigate the environmental fate of these compounds and their biotransformation mechanisms, the authors used inocula from a variety of different water sources and dosed biologically active microcosms with approximately 1400 ng/L of Trenbolone acetate metabolites, including 17β-Trenbolone, trendione, and 17α-Trenbolone. To investigate aerobic biotransformation rates and interconversions between known Trenbolone acetate metabolites, gas chromatography-tandem mass spectrometry was used to measure concentrations and assess product distributions as a function of time. High-resolution liquid chromatography-tandem mass spectrometry (LC-MS/MS) was used to characterize novel transformation products and potential transformation pathways. Kinetic analysis yields observed half-lives of approximately 0.9 d, 1.3 d, and 2.2 d for 17β-Trenbolone, trendione, and 17α-Trenbolone, respectively, at 20 °C, although colder conditions increased half-lives to 8.5 d and biphasic transformation was observed. Relative to reported faster attenuation rates in soils, Trenbolone acetate metabolites are likely more persistent in aqueous systems. Product distributions indicate an enzymatic preference for biotransformation between trendione and 17β-Trenbolone. The LC-MS/MS characterization indicates dehydrogenation products as the major detectable products and demonstrates that major structural elements responsible for bioactivity in steroids are likely retained during biotransformation.
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Coupled reversion and stream-hyporheic exchange processes increase environmental persistence of Trenbolone metabolites
Nature Communications, 2015Co-Authors: Adam S. Ward, David M. Cwiertny, Edward P. Kolodziej, Colleen C. BrehmAbstract:Existing regulatory frameworks for aquatic pollutants in the United States are idealized, often lacking mechanisms to account for contaminants characterized by (1) bioactivity of both the parent and transformation products and (2) reversible transformations (that is, metastable products) driven by chemical or physical heterogeneities. Here, we modelled a newly discovered product-to-parent reversion pathway for Trenbolone acetate (TBA) metabolites. We show increased exposure to the primary metabolite, 17α-Trenbolone (17α-TBOH), and elevated concentrations of the still-bioactive primary photoproduct hydroxylated 17α-TBOH, produced via phototransformation and then converted back to 17α-Trenbolone in perpetually dark hyporheic zones that exchange continuously with surface water photic zones. The increased persistence equates to a greater potential hazard from parent-product joint bioactivity at locations and times when reversion is a dominant Trenbolone fate pathway. Our study highlights uncertainties and vulnerabilities with current paradigms in risk characterization.
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Identification and environmental implications of photo-transformation products of Trenbolone acetate metabolites.
Environmental Science & Technology, 2013Co-Authors: Edward P. Kolodziej, Kristy L. Forsgren, Daniel Schlenk, Sarah A. Long, James B. Gloer, Gerrad D. Jones, Jonas Baltrusaitis, David M. CwiertnyAbstract:Despite the widespread use of the anabolic androgen Trenbolone acetate (TBA) in animal agriculture, evidence demonstrating the occurrence of TBA metabolites such as 17β-Trenbolone (17β-TBOH), 17α-Trenbolone (17α-TBOH), and trendione (TBO) is relatively scarce, potentially due to rapid transformation processes such as direct photolysis. Therefore, we investigated the phototransformation of TBA metabolites and associated ecological implications by characterizing the photoproducts arising from the direct photolysis of 17β-TBOH, 17α-TBOH, and TBO and their associated ecotoxicity. LC-HRMS/MS analysis identified a range of hydroxylated products that were no longer photoactive, with primary photoproducts consisting of monohydroxy species and presumptive diastereomers. Also observed were higher-order hydroxylated products probably formed via subsequent reaction of primary photoproducts. NMR analysis confirmed the formation of 12,17-dihydroxy-estra-5(10),9(11),dien-3-one (12-hydroxy-TBOH; 2.2 mg), 10,12,17-trihydroxy-estra-4,9(11),dien-3-one (10,12-dihydroxy-TBOH; 0.7 mg), and a ring-opened 11,12-dialdehyde oxidation product (TBOH-11,12-dialdehyde; 1.0 mg) after irradiation of ∼14 mg of 17β-Trenbolone. Though unconfirmed by NMR, our data suggest that the formation of additional isomeric products may occur, likely due to the reactivity of the unique 4,9,11 conjugated triene structure of Trenbolone. In vivo exposure studies employing Japanese medaka (Oryzias latipes) indicate that low concentrations of 17α-TBOH photoproduct mixtures can alter ovarian follicular development, and photoproducts alter whole-body 17β-estradiol levels. Therefore, direct photolysis yields photoproducts with strong structural similarity to parent steroids, and these photoproducts still retain enough biological activity to elicit observable changes to endocrine function at trace concentrations. These data indicate that environmental transformation processes do not necessarily reduce steroid hormone ecotoxicity.
Jon F. Ericson - One of the best experts on this subject based on the ideXlab platform.
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degradation and transformation of 17α Trenbolone in aerobic water sediment systems
Environmental Toxicology and Chemistry, 2017Co-Authors: Joseph A. Robinson, Jane P. Staveley, Walter J. Smolenski, Jon F. EricsonAbstract:Synovex® ONE is an extended-release implant containing the active ingredients estradiol benzoate and Trenbolone acetate for use in beef steers and heifers. Trenbolone acetate is rapidly hydrolyzed in cattle to form 17β-Trenbolone and its isomer, 17α-Trenbolone, which are further transformed to a secondary metabolite, trendione. As part of the environmental assessment for the use of Synovex ONE, data were generated to characterize the fate of 17α-Trenbolone, which is the principal metabolite found in cattle excreta, in the environment. A study was conducted to determine the degradation and transformation of [14 C]-17α-Trenbolone in 2 representative water-sediment systems under aerobic conditions. The same transformation products, 17β-Trenbolone and trendione, were formed, principally in the sediment phase, in both systems. From the production of these transformation products, the 50% disappearance time (DT50) values of 17β-Trenbolone and trendione were determined, along with the DT50 values of the parent compound and the total drug (17α-Trenbolone + 17β-Trenbolone + trendione). The DT50 values for the total system (aqueous and sediment phase) and for the total residues (17α-Trenbolone + 17β-Trenbolone + trendione) in the 2 systems were 34.7 d and 53.3 d, respectively. Environ Toxicol Chem 2017;36:630-635. © 2016 SETAC.
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Degradation and transformation of 17α‐Trenbolone in aerobic water–sediment systems
Environmental Toxicology and Chemistry, 2016Co-Authors: Joseph A. Robinson, Jane P. Staveley, Walter J. Smolenski, Jon F. EricsonAbstract:Synovex® ONE is an extended-release implant containing the active ingredients estradiol benzoate and Trenbolone acetate for use in beef steers and heifers. Trenbolone acetate is rapidly hydrolyzed in cattle to form 17β-Trenbolone and its isomer, 17α-Trenbolone, which are further transformed to a secondary metabolite, trendione. As part of the environmental assessment for the use of Synovex ONE, data were generated to characterize the fate of 17α-Trenbolone, which is the principal metabolite found in cattle excreta, in the environment. A study was conducted to determine the degradation and transformation of [14 C]-17α-Trenbolone in 2 representative water-sediment systems under aerobic conditions. The same transformation products, 17β-Trenbolone and trendione, were formed, principally in the sediment phase, in both systems. From the production of these transformation products, the 50% disappearance time (DT50) values of 17β-Trenbolone and trendione were determined, along with the DT50 values of the parent compound and the total drug (17α-Trenbolone + 17β-Trenbolone + trendione). The DT50 values for the total system (aqueous and sediment phase) and for the total residues (17α-Trenbolone + 17β-Trenbolone + trendione) in the 2 systems were 34.7 d and 53.3 d, respectively. Environ Toxicol Chem 2017;36:630-635. © 2016 SETAC.
Jane P. Staveley - One of the best experts on this subject based on the ideXlab platform.
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degradation and transformation of 17α Trenbolone in aerobic water sediment systems
Environmental Toxicology and Chemistry, 2017Co-Authors: Joseph A. Robinson, Jane P. Staveley, Walter J. Smolenski, Jon F. EricsonAbstract:Synovex® ONE is an extended-release implant containing the active ingredients estradiol benzoate and Trenbolone acetate for use in beef steers and heifers. Trenbolone acetate is rapidly hydrolyzed in cattle to form 17β-Trenbolone and its isomer, 17α-Trenbolone, which are further transformed to a secondary metabolite, trendione. As part of the environmental assessment for the use of Synovex ONE, data were generated to characterize the fate of 17α-Trenbolone, which is the principal metabolite found in cattle excreta, in the environment. A study was conducted to determine the degradation and transformation of [14 C]-17α-Trenbolone in 2 representative water-sediment systems under aerobic conditions. The same transformation products, 17β-Trenbolone and trendione, were formed, principally in the sediment phase, in both systems. From the production of these transformation products, the 50% disappearance time (DT50) values of 17β-Trenbolone and trendione were determined, along with the DT50 values of the parent compound and the total drug (17α-Trenbolone + 17β-Trenbolone + trendione). The DT50 values for the total system (aqueous and sediment phase) and for the total residues (17α-Trenbolone + 17β-Trenbolone + trendione) in the 2 systems were 34.7 d and 53.3 d, respectively. Environ Toxicol Chem 2017;36:630-635. © 2016 SETAC.
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sorption and desorption of 17α Trenbolone and trendione on five soils
Environmental Toxicology and Chemistry, 2017Co-Authors: Joseph A. Robinson, Jane P. Staveley, Walter J. SmolenskiAbstract:The metabolites 17α-Trenbolone and 17α-estradiol are principal metabolites in cattle excreta following the administration of Synovex® ONE, which contains Trenbolone acetate and estradiol benzoate. As part of the environmental assessment of the use of Synovex ONE, data were generated to characterize the fate of 17α-Trenbolone, and its metabolite trendione in the environment. Predictions of the fate and environmental concentrations of these hormones after land application require accurate estimates of the sorption of these compounds in soils. The sorption and desorption of 17α-Trenbolone and trendione were measured at 5 nominal concentrations in 5 soils from different geologic settings using a batch equilibrium technique following guideline 106 of the Organisation for Economic Co-operation and Development. Both the sorption and desorption of 17α-Trenbolone and trendione to soils were adequately described by the Freundlich sorption model and by linear partition coefficients. The mean sorption coefficients were 9.04 mL/g and 32.2 mL/g for 17α-Trenbolone and trendione, respectively. The corresponding mean Freundlich sorption exponents were 0.88 and 0.98, respectively. Sorption of 17α-Trenbolone and trendione was correlated principally with soil organic carbon. Average sorption coefficients normalized to soil organic carbon content (KOC ) were 460 mL/g and 1804 mL/g for 17α-Trenbolone and trendione, respectively. The mean desorption coefficients were 22.1 mL/g and 43.8 mL/g for 17α-Trenbolone and trendione, respectively. Calculated hysteresis coefficients based on the difference in the area between sorption and desorption isotherms indicated that sorption equilibrium was not fully reversible and hysteresis of desorption isotherms occurred for both 17α-Trenbolone and trendione. Environ Toxicol Chem 2017;36:613-620. © 2016 SETAC.
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Sorption and desorption of 17α‐Trenbolone and trendione on five soils
Environmental Toxicology and Chemistry, 2017Co-Authors: Joseph A. Robinson, Jane P. Staveley, Walter J. SmolenskiAbstract:The metabolites 17α-Trenbolone and 17α-estradiol are principal metabolites in cattle excreta following the administration of Synovex® ONE, which contains Trenbolone acetate and estradiol benzoate. As part of the environmental assessment of the use of Synovex ONE, data were generated to characterize the fate of 17α-Trenbolone, and its metabolite trendione in the environment. Predictions of the fate and environmental concentrations of these hormones after land application require accurate estimates of the sorption of these compounds in soils. The sorption and desorption of 17α-Trenbolone and trendione were measured at 5 nominal concentrations in 5 soils from different geologic settings using a batch equilibrium technique following guideline 106 of the Organisation for Economic Co-operation and Development. Both the sorption and desorption of 17α-Trenbolone and trendione to soils were adequately described by the Freundlich sorption model and by linear partition coefficients. The mean sorption coefficients were 9.04 mL/g and 32.2 mL/g for 17α-Trenbolone and trendione, respectively. The corresponding mean Freundlich sorption exponents were 0.88 and 0.98, respectively. Sorption of 17α-Trenbolone and trendione was correlated principally with soil organic carbon. Average sorption coefficients normalized to soil organic carbon content (KOC ) were 460 mL/g and 1804 mL/g for 17α-Trenbolone and trendione, respectively. The mean desorption coefficients were 22.1 mL/g and 43.8 mL/g for 17α-Trenbolone and trendione, respectively. Calculated hysteresis coefficients based on the difference in the area between sorption and desorption isotherms indicated that sorption equilibrium was not fully reversible and hysteresis of desorption isotherms occurred for both 17α-Trenbolone and trendione. Environ Toxicol Chem 2017;36:613-620. © 2016 SETAC.
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Reproductive effects on freshwater fish exposed to 17α-Trenbolone and 17α-estradiol.
Environmental Toxicology and Chemistry, 2016Co-Authors: Joseph A. Robinson, Jane P. Staveley, Lisa A. ConstantineAbstract:17α-Trenbolone and 17α-estradiol are principal metabolites in cattle excreta following the administration of Synovex® ONE, which contains Trenbolone acetate and estradiol benzoate. As part of the environmental assessment of the use of Synovex® ONE, data were generated to characterize the effects of 17α-Trenbolone and 17α-estradiol on the reproduction of freshwater fish. These substances are known endocrine disruptors, so the purpose of testing was not to clarify these properties but to identify concentrations representing population-relevant effects for use in risk characterization. The short-term reproduction assay was conducted with 17α-Trenbolone using the fathead minnow (Pimephales promelas) and the medaka (Oryzias latipes) and with 17α-estradiol using the fathead minnow. Adverse effects on the population-relevant endpoints of survival and fecundity were used to establish the no-observed-effect concentration (NOEC) and the lowest-observed-effect concentration (LOEC) for each study. For 17α-Trenbolone, adverse effects on fecundity of the fathead minnow occurred at 120 ng/L; this was the LOEC, and the NOEC was 35 ng/L. 17β-Trenbolone did not adversely affect survival and fecundity of medaka at the concentrations tested, resulting in a NOEC of 110 ng/L and a LOEC of >110 ng/L. 17α-Estradiol did not adversely impact survival and fecundity of the fathead minnow at the concentrations tested, resulting in a NOEC and LOEC of 250 ng/L and >250 ng/L, respectively. Environ Toxicol Chem 2017;36:636-644. © 2016 SETAC.
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Degradation and transformation of 17α‐Trenbolone in aerobic water–sediment systems
Environmental Toxicology and Chemistry, 2016Co-Authors: Joseph A. Robinson, Jane P. Staveley, Walter J. Smolenski, Jon F. EricsonAbstract:Synovex® ONE is an extended-release implant containing the active ingredients estradiol benzoate and Trenbolone acetate for use in beef steers and heifers. Trenbolone acetate is rapidly hydrolyzed in cattle to form 17β-Trenbolone and its isomer, 17α-Trenbolone, which are further transformed to a secondary metabolite, trendione. As part of the environmental assessment for the use of Synovex ONE, data were generated to characterize the fate of 17α-Trenbolone, which is the principal metabolite found in cattle excreta, in the environment. A study was conducted to determine the degradation and transformation of [14 C]-17α-Trenbolone in 2 representative water-sediment systems under aerobic conditions. The same transformation products, 17β-Trenbolone and trendione, were formed, principally in the sediment phase, in both systems. From the production of these transformation products, the 50% disappearance time (DT50) values of 17β-Trenbolone and trendione were determined, along with the DT50 values of the parent compound and the total drug (17α-Trenbolone + 17β-Trenbolone + trendione). The DT50 values for the total system (aqueous and sediment phase) and for the total residues (17α-Trenbolone + 17β-Trenbolone + trendione) in the 2 systems were 34.7 d and 53.3 d, respectively. Environ Toxicol Chem 2017;36:630-635. © 2016 SETAC.
