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Card M.L.,Ohio State University | Card M.L.,National Research Center for Environmental Toxicology | Schnoor J.L.,University of Iowa | Chin Y.-P.,Ohio State University
Journal of Agricultural and Food Chemistry | Year: 2012

Runoff from manure-fertilized crop fields constitutes a significant source of natural estrogens (e.g., estradiol [17β-E2] and estrone [E1]) and synthetic estrogen mimics (e.g., zeranol [α-ZAL] and zearalanone [ZAN]) in the environment. However, processes such as sorption to and uptake by plants may inhibit the environmental mobility of hormonally active compounds. Sorption to dried root tissue was assessed in batch sorption tests, and resulting sorption isotherms were nonlinear at aqueous concentrations below 0.1 μM and linear above that limit. To evaluate the role of crop plants in the environmental fate of such compounds, we exposed hydroponic solutions containing 2 μM 17β-E2, E1, α-ZAL, or ZAN to maize seedlings. After 22 days of exposure, α-ZAL and ZAN concentrations decreased by more than 96%, and 17β-E2 and E1 were undetectable. The decrease in α-ZAL and ZAN concentrations in maize-exposed solutions was initially slow, but the observed uptake exceeded that predicted by sorption alone within 3 d. All four estrogens were detected in root tissues at concentrations up to 0.19 μmol g -1, with concentrations peaking after 1-3 days of exposure. Only 17β-E2 and α-ZAL were detected in shoots, and maximum concentrations were measured after 2 days for 17β-E2 (0.02 μmol g-1) and 16 days for α-ZAL (0.8 nmol g-1). Concentrations measured in root and shoot tissues were 82% or less than those predicted by a partition-limited uptake model, which is attributed to transformation and possibly irreversible binding processes. © 2012 American Chemical Society. Source


Card M.L.,Ohio State University | Card M.L.,National Research Center for Environmental Toxicology | Schnoor J.L.,University of Iowa | Chin Y.-P.,Ohio State University
Environmental Science and Technology | Year: 2013

In agricultural fields, crop plants may transform or degrade hormonally active compounds in manure used as fertilizer and thereby affect the overall endocrine-disrupting activity of agricultural runoff. This study examined the transformation of two natural steroid estrogens [17β-estradiol (17β-E2) and estrone (E1)] and two synthetic estrogen mimics [zeranol (α-ZAL) and zearalanone (ZAN)] by maize seedlings. Growing whole maize seedlings in hydroponic solutions of target estrogens resulted in both oxidative (i.e., 17β-E2 to E1 and α-ZAL to ZAN) and reductive (i.e., E1 to 17β-E2 and ZAN to α-ZAL) transformations. Although all four estrogens accumulated in maize roots as both parents and products, the shoots contained only 17β-E2 and α-ZAL, regardless of whether they were the parent or the product. Crude plant enzyme extracts led to substantial reductive transformations but created only trace amounts of oxidation products. In contrast, only oxidative transformations occurred in solutions exposed to plant-associated microbes. Thus, the combined effects of plant enzymes and plant-associated microbes account for the reversible transformations observed with whole plants. These effects are expected to generally decrease the overall estrogenicity of runoff from manure-fertilized fields. © 2013 American Chemical Society. Source


Lopez S.H.,University of Almeria | Ulaszewska M.M.,Research and Innovation Center | Hernando M.D.,National Institute for Agricultural and Food Research and Technology INIA | Bueno M.J.M.,Montpellier University | And 3 more authors.
Environmental Science and Pollution Research | Year: 2014

This study describes a comprehensive strategy for detecting and elucidating the chemical structures of expected and unexpected transformation products (TPs) from chemicals found in river water and effluent wastewater samples, using liquid chromatography coupled to electrospray ionization quadrupole-time-of-flight mass spectrometer (LC-ESI-QTOF-MS), with post-acquisition data processing and an automated search using an in-house database. The efficacy of the mass defect filtering (MDF) approach to screen metabolites from common biotransformation pathways was tested, and it was shown to be sufficiently sensitive and applicable for detecting metabolites in environmental samples. Four omeprazole metabolites and two venlafaxine metabolites were identified in river water samples. This paper reports the analytical results obtained during 2 years of monitoring, carried out at eight sampling points along the Henares River (Spain). Multiresidue monitoring, for targeted analysis, includes a group of 122 chemicals, amongst which are pharmaceuticals, personal care products, pesticides and PAHs. For this purpose, two analytical methods were used based on direct injection with a LC-ESI-QTOF-MS system and stir bar sorptive extraction (SBSE) with bi-dimensional gas chromatography coupled with a time-of-flight spectrometer (GCxGC-EI-TOF-MS). © 2014, Springer-Verlag Berlin Heidelberg. Source


Drage D.,University of Birmingham | Drage D.,National Research Center for Environmental Toxicology | Mueller J.F.,National Research Center for Environmental Toxicology | Birch G.,University of Sydney | And 3 more authors.
Science of the Total Environment | Year: 2015

This paper presents the first historical data on the occurrence of polybrominated diphenyl ethers (PBDEs) and hexabromocyclododecane (HBCDs) in estuarine sediment from Australia. Sediment cores and surficial sediment samples were collected from four locations within Sydney estuary, Australia. Large increases in concentrations were observed for all compounds between 1980 and 2014, especially for BDE-209 (representative usage of Deca-BDE commercial mixture), which was found in surficial sediment at an average concentration of 42ng/g dry wt (21-65ng/g dry wt). PBDE congeners representative of both the Penta- and Octa-BDE commercial mixtures (∑6PBDEs) were also found in their highest concentrations in surficial sediments (average: 1.3ng/g dry wt; range: 0.65-2.5ng/g dry wt). PBDE concentrations in surficial sediments were relatively high when compared with those presented in the available literature. This suggests that their input into the Sydney estuary has not decreased since their bans almost a decade earlier. After a sharp increase in the 1990s, HBCD concentrations peaked at an average of 3.5ng/g dry wt (1.8-5.3ng/g dry wt) in surficial samples. With global legislation on HBCDs allowing its usage for the next 10years, it is expected that its input into the estuary is likely to continue. © 2015 Elsevier B.V. Source

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