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1.
Sci Total Environ ; 710: 136247, 2020 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-31923660

RESUMO

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 17ß-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.


Assuntos
Carne Vermelha , Androgênios , Animais , Bovinos , Estrogênios , Esterco , Progestinas , Água , Poluentes Químicos da Água
2.
J Environ Qual ; 45(5): 1776-1781, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27695756

RESUMO

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.


Assuntos
Hormônios/análise , Poluentes Químicos da Água/análise , Filtração , Material Particulado , Movimentos da Água
3.
Environ Toxicol Chem ; 29(11): 2481-90, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20865698

RESUMO

Degradation of hormones that may occur during storage of surface water samples can lead to underestimations in estrogenic and androgenic activities and inaccuracies in hormone concentrations. The current study investigated the use of sodium azide, hydrochloric acid (HCl), and sulfuric acid (H2SO4) to inhibit the degradation of hormones and estrogenic and androgenic activities in samples of surface water runoff from cattle manure-amended fields during storage at 4°C. Hormones and hormone metabolites were extracted using solid-phase extraction and analyzed using high-performance liquid chromatography (HPLC) with tandem MS. Estrogenic and androgenic activities were assessed by E-screen and A-screen, respectively. Results of the current study indicate significant degradation of estrogenic, androgenic, and progestogenic hormones and activities, which is likely attributable to microbial activity, within hours of sample collection. The inclusion of internal standards provides a means to account for hormone losses caused by extraction inefficiency and to some extent degradation. However, internal standards are unable to adequately account for significant losses and are not available for E-screen and A-screen. Sodium azide did not adequately inhibit androgen degradation at the concentration used (1 g/L). Acid preservation (HCl or H2SO4, pH 2) stabilized the estrogenic and androgenic activities, and coupling acid preservation with the use of internal standards resulted in reliable and accurate recovery of a suite of androgens, estrogens, and progestogens for up to 14 d of storage at 4°C.


Assuntos
Androgênios/análise , Estrogênios/análise , Hormônios/análise , Poluentes Químicos da Água/química , Androgênios/metabolismo , Cromatografia Líquida de Alta Pressão , Estrogênios/metabolismo , Hormônios/metabolismo , Ácido Clorídrico/farmacologia , Azida Sódica/farmacologia , Extração em Fase Sólida , Ácidos Sulfúricos/farmacologia , Propriedades de Superfície , Espectrometria de Massas em Tandem
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