9 research outputs found
Polyoxyethylene Tallow Amine, a Glyphosate Formulation Adjuvant: Soil Adsorption Characteristics, Degradation Profile, and Occurrence on Selected Soils from Agricultural Fields in Iowa, Illinois, Indiana, Kansas, Mississippi, and Missouri
Polyoxyethylene
tallow amine (POEA) is an inert ingredient added to formulations of
glyphosate, the most widely applied agricultural herbicide. POEA has
been shown to have toxic effects to some aquatic organisms making
the potential transport of POEA from the application site into the
environment an important concern. This study characterized the adsorption
of POEA to soils and assessed its occurrence and homologue distribution
in agricultural soils from six states. Adsorption experiments of POEA
to selected soils showed that POEA adsorbed much stronger than glyphosate;
calcium chloride increased the binding of POEA; and the binding of
POEA was stronger in low pH conditions. POEA was detected on a soil
sample from an agricultural field near Lawrence, Kansas, but with
a loss of homologues that contain alkenes. POEA was also detected
on soil samples collected between February and early March from corn
and soybean fields from ten different sites in five other states (Iowa,
Illinois, Indiana, Missouri, Mississippi). This is the first study
to characterize the adsorption of POEA to soil, the potential widespread
occurrence of POEA on agricultural soils, and the persistence of the
POEA homologues on agricultural soils into the following growing season
Use and Environmental Occurrence of Antibiotics in Freestall Dairy Farms with Manured Forage Fields
Environmental releases of antibiotics from concentrated animal feeding operations (CAFOs) are of increasing regulatory concern. This study investigates the use and occurrence of antibiotics in dairy CAFOs and their potential transport into first-encountered groundwater. On two dairies we conducted four seasonal sampling campaigns, each across 13 animal production and waste management systems and associated environmental pathways: application to animals, excretion to surfaces, manure collection systems, soils, and shallow groundwater. Concentrations of antibiotics were determined using on line solid phase extraction (OLSPE) and liquid chromatography-tandem mass spectrometry (LC/MS/MS) with electrospray ionization (ESI) for water samples, and accelerated solvent extraction (ASE) LC/MS/MS with ESI for solid samples. A variety of antibiotics were applied at both farms leading to antibiotics excretion of several hundred grams per farm per day. Sulfonamides, tetracyclines, and their epimers/isomers, and lincomycin were most frequently detected. Yet, despite decades of use, antibiotic occurrence appeared constrained to within farm boundaries. The most frequent antibiotic detections were associated with lagoons, hospital pens, and calf hutches. When detected below ground, tetracyclines were mainly found in soils, whereas sulfonamides were found in shallow groundwater reflecting key differences in their physicochemical properties. In manure lagoons, 10 compounds were detected including tetracyclines and trimethoprim. Of these 10, sulfadimethoxine, sulfamethazine, and lincomycin were found in shallow groundwater directly downgradient from the lagoons. Antibiotics were sporadically detected in field surface samples on fields with manure applications, but not in underlying sandy soils. Sulfadimethoxine and sulfamethazine were detected in shallow groundwater near field flood irrigation gates, but at highly attenuated levels
Exposure to the Contraceptive Progestin, Gestodene, Alters Reproductive Behavior, Arrests Egg Deposition, and Masculinizes Development in the Fathead Minnow (<i>Pimephales promelas</i>)
Endogenous
progestogens and pharmaceutical progestins enter the
environment through wastewater treatment plant effluent and agricultural
field runoff. Lab studies demonstrate strong, negative exposure effects
of these chemicals on aquatic vertebrate reproduction. Behavior can
be a sensitive, early indicator of exposure to environmental contaminants
associated with altered reproduction yet is rarely examined in ecotoxicology
studies. Gestodene is a human contraceptive progestin and a potent
activator of fish androgen receptors. Our objective was to test the
effects of gestodene on reproductive behavior and associated egg deposition
in the fathead minnow. After only 1 day, males exposed to ng/L of
gestodene were more aggressive and less interested in courtship and
mating, and exposed females displayed less female courtship behavior.
Interestingly, 25% of the gestodene tanks contained a female that
drove the male out of the breeding tile and displayed male-typical
courtship behaviors toward the other female. Gestodene decreased or
arrested egg deposition with no observed gonadal histopathology. Together,
these results suggest that effects on egg deposition are primarily
due to altered reproductive behavior. The mechanisms by which gestodene
disrupts behavior are unknown. Nonetheless, the rapid and profound
alterations of the reproductive biology of gestodene-exposed fish
suggest that wild populations could be similarly affected
Transport of Steroid Hormones, Phytoestrogens, and Estrogenic Activity across a Swine Lagoon/Sprayfield System
The
inflow, transformation, and attenuation of natural steroid
hormones and phytoestrogens and estrogenic activity were assessed
across the lagoon/sprayfield system of a prototypical commercial swine
sow operation. Free and conjugated steroid hormones (estrogens, androgens,
and progesterone) were detected in urine and feces of sows across
reproductive stages, with progesterone being the most abundant steroid
hormone. Excreta also contained phytoestrogens indicative of a soy-based
diet, particularly, daidzein, genistein, and equol. During storage
in barn pits and the anaerobic lagoon, conjugated hormones dissipated,
and androgens and progesterone were attenuated. Estrone and equol
persisted along the waste disposal route. Following application of
lagoon slurry to agricultural soils, all analytes exhibited attenuation
within 2 days. However, analytes including estrone, androstenedione,
progesterone, and equol remained detectable in soil at 2 months postapplication.
Estrogenic activity in the yeast estrogen screen and T47D-KBluc in
vitro bioassays generally tracked well with analyte concentrations.
Estrone was found to be the greatest contributor to estrogenic activity
across all sample types. This investigation encompasses the most comprehensive
suite of natural hormone and phytoestrogen analytes examined to date
across a livestock lagoon/sprayfield and provides global insight into
the fate of these analytes in this widely used waste management system
Exposure to the Contraceptive Progestin, Gestodene, Alters Reproductive Behavior, Arrests Egg Deposition, and Masculinizes Development in the Fathead Minnow (<i>Pimephales promelas</i>)
Endogenous
progestogens and pharmaceutical progestins enter the
environment through wastewater treatment plant effluent and agricultural
field runoff. Lab studies demonstrate strong, negative exposure effects
of these chemicals on aquatic vertebrate reproduction. Behavior can
be a sensitive, early indicator of exposure to environmental contaminants
associated with altered reproduction yet is rarely examined in ecotoxicology
studies. Gestodene is a human contraceptive progestin and a potent
activator of fish androgen receptors. Our objective was to test the
effects of gestodene on reproductive behavior and associated egg deposition
in the fathead minnow. After only 1 day, males exposed to ng/L of
gestodene were more aggressive and less interested in courtship and
mating, and exposed females displayed less female courtship behavior.
Interestingly, 25% of the gestodene tanks contained a female that
drove the male out of the breeding tile and displayed male-typical
courtship behaviors toward the other female. Gestodene decreased or
arrested egg deposition with no observed gonadal histopathology. Together,
these results suggest that effects on egg deposition are primarily
due to altered reproductive behavior. The mechanisms by which gestodene
disrupts behavior are unknown. Nonetheless, the rapid and profound
alterations of the reproductive biology of gestodene-exposed fish
suggest that wild populations could be similarly affected
Exposure to the Contraceptive Progestin, Gestodene, Alters Reproductive Behavior, Arrests Egg Deposition, and Masculinizes Development in the Fathead Minnow (<i>Pimephales promelas</i>)
Endogenous
progestogens and pharmaceutical progestins enter the
environment through wastewater treatment plant effluent and agricultural
field runoff. Lab studies demonstrate strong, negative exposure effects
of these chemicals on aquatic vertebrate reproduction. Behavior can
be a sensitive, early indicator of exposure to environmental contaminants
associated with altered reproduction yet is rarely examined in ecotoxicology
studies. Gestodene is a human contraceptive progestin and a potent
activator of fish androgen receptors. Our objective was to test the
effects of gestodene on reproductive behavior and associated egg deposition
in the fathead minnow. After only 1 day, males exposed to ng/L of
gestodene were more aggressive and less interested in courtship and
mating, and exposed females displayed less female courtship behavior.
Interestingly, 25% of the gestodene tanks contained a female that
drove the male out of the breeding tile and displayed male-typical
courtship behaviors toward the other female. Gestodene decreased or
arrested egg deposition with no observed gonadal histopathology. Together,
these results suggest that effects on egg deposition are primarily
due to altered reproductive behavior. The mechanisms by which gestodene
disrupts behavior are unknown. Nonetheless, the rapid and profound
alterations of the reproductive biology of gestodene-exposed fish
suggest that wild populations could be similarly affected
Antecedent and Post-Application Rain Events Trigger Glyphosate Transport from Runoff-Prone Soils
Recent environmental surveys report
widespread detections of the
herbicide glyphosate [<i>N</i>-(phosphonomethyl)Âglycine]
in surface waters, despite its strong immobilization and rapid biodegradation
in soils. We performed four high-frequency sampling campaigns (from
2015 to 2017) following controlled spray applications on an experimental
perennial grass field site with wetness-prone marginal soils. We monitored
dissolved glyphosate concentrations in the outflow (runoff and shallow
drainage) using liquid chromatography–mass spectrometry and
enzyme-linked immunosorbent assays. Rainfall-triggered outflow events
occurred between 3 and 13 days following spray application. Outflow
concentrations varied widely from nondetectable levels to 90 μg
L<sup>–1</sup>, peaking during the first significant outflow
event in each campaign and diminishing as flows subsided. Subsequent
outflow peaks caused concentrations to increase again but to a lesser
extent. Cumulative mass efflux in outflow across the different campaigns
ranged from 0.06 to 1.0% of applied glyphosate. Cumulative glyphosate
losses in the outflow were not associated with total rainfall during
the postspray sampling period, but rather with soil hydrologic conditions
at the time of spraying as reflected by the 7 day cumulative prespray
rainfall, with wetter antecedent conditions favoring greater cumulative
mobilization. Avoiding spraying under such conditions may mitigate
potential glyphosate mobilization
Persistence and Potential Effects of Complex Organic Contaminant Mixtures in Wastewater-Impacted Streams
Natural and synthetic organic contaminants in municipal
wastewater
treatment plant (WWTP) effluents can cause ecosystem impacts, raising
concerns about their persistence in receiving streams. In this study,
Lagrangian sampling, in which the same approximate parcel of water
is tracked as it moves downstream, was conducted at Boulder Creek,
Colorado and Fourmile Creek, Iowa to determine in-stream transport
and attenuation of organic contaminants discharged from two secondary
WWTPs. Similar stream reaches were evaluated, and samples were collected
at multiple sites during summer and spring hydrologic conditions.
Travel times to the most downstream (7.4 km) site in Boulder Creek
were 6.2 h during the summer and 9.3 h during the spring, and to the
Fourmile Creek 8.4 km downstream site times were 18 and 8.8 h, respectively.
Discharge was measured at each site, and integrated composite samples
were collected and analyzed for >200 organic contaminants including
metal complexing agents, nonionic surfactant degradates, personal
care products, pharmaceuticals, steroidal hormones, and pesticides.
The highest concentration (>100 μg L<sup>–1</sup>)
compounds
detected in both WWTP effluents were ethylenediaminetetraacetic acid
and 4-nonylphenolethoxycarboxylate oligomers, both of which persisted
for at least 7 km downstream from the WWTPs. Concentrations of pharmaceuticals
were lower (<1 μg L<sup>–1</sup>), and several compounds,
including carbamazepine and sulfamethoxazole, were detected throughout
the study reaches. After accounting for in-stream dilution, a complex
mixture of contaminants showed little attenuation and was persistent
in the receiving streams at concentrations with potential ecosystem
implications