Fate of 17ß-estradiol in anaerobic lagoon digesters.

The fate of [C]17ß-estradiol ([C]E2) was monitored for 42 d in triplicate 10-L anaerobic digesters. Total radioactive residues decreased rapidly in the liquid layer of the digesters and reached a steady-state value of 22 to 26% of the initial dose after 5 d. High-performance liquid chromatography and liquid chromatography-tandem mass spectrometry analyses of the liquid layer of the anaerobic digesters indicated a rapid degradation of E2 to estrone (E1), which readily adsorbed to the sludge layer subsequent to its formation. Estrone was the predominant steroid identified under anaerobic digestion in the liquid layer or sorbed to sludge at 42 d. Methane formation represented 11.1 ± 5.7% of the initial E2 fortification with 0.3 to 0.5% of the starting E2 mineralized to carbon dioxide. Maximum [C]methane production appeared between Days 4 and 7. An estimate of estrogenicity of the final product based on reported estrogen equivalents for E1 and E2 was 2% of the original in active digesters. Anaerobic digestion of swine waste has several management benefits; moreover, this study demonstrated that it reduces the potential of environmental release of estrogens, which are known endocrine disruptors.

Development of an ultra-high-pressure liquid chromatography-tandem mass spectrometry multi-residue sulfonamide method and its application to water, manure slurry, and soils from swine rearing facilities.

An analytical method was developed using ultra-high-pressure liquid chromatography-triple quadrupole-tandem mass spectrometry (UHPLC-TQ-MS/MS) to simultaneously analyze 14 sulfonamides (SA) in 6 min. Despite the rapidity of the assay the system was properly re-equilibrated in this time. No carryover was observed even after high analyte concentrations. The instrumental detection limit based on signal-to-noise ratio (S/N)>3, was below 1 pg/microL (5 pg on column) for all SAs except sulfachloropyridazine. Surface water, ground water, soil, and slurry manure contained in storage ponds in and around swine [Sus scrofa domesticus] rearing facilities were analyzed. Sample cleanup for ground water and surface water included using solid phase extraction (SPE) using Oasis hydrophilic-lipophilic balance (HLB) cartridges. The soil and slurry manure required tandem strong anion exchange (SAX) and HLB solid phase extraction cartridges for sample cleanup. With few exceptions, the recoveries ranged from 60 to 100% for all matrices. The minimum detectable levels were below 2.0 ng/L for water, 30 ng/L for slurry manure, and 45 ng/kg for soil except for sulfachloropyridazine. The coefficient of variation (CV) was within 20% for most of the compounds analyzed. Using this method, sulfamethazine concentrations of 2250-5060 ng/L, sulfamethoxazole concentrations of 108-1.47 x 10(6)ng/L, and sulfathiazole concentrations of 785-1700 ng/L were found in the slurry manure. Sulfadimethoxine (2.0-32 ng/L), sulfamethazine (2.0-5.1 ng/L), and sulfamethoxazole (20.5-43.0 ng/L) were found in surface water and ground water. In top soil (0-15 cm), sulfamethazine ranged 34.5-663 ng/kg dry weight in those locations that received slurry manure as a nutrient; no SAs were found in the soil depths between 46 and 61 cm. The speed makes the method practical for medium to high throughput applications. The sensitivity and positive analyte identification make the method suitable for the demanding requirements for real world applications.

Occurrence and pathways of manure-borne 17beta-estradiol in vadose zone water.

The hormone 17beta-estradiol (E2) can cause endocrine disruption in sensitive species at part per trillion concentrations. The persistence and transport pathways of manure-borne E2 in agricultural soils were determined by comparing its occurrence with the transfer of water and the transport of non-sorbing fluorobenzoic acid (FBA) tracers. This comparison was done using capillary wick lysimeters installed 0.61m beneath three corn (Zea mays L.) plots that receive swine (Sus scrofa domesticus) manure from various sources. An additional control plot was included that received no manure. Soil water transfer was modeled to compare actual versus predicted percolation. On average, lysimeters collected 61% of the expected percolation and 8% of the FBA. There were frequent E2 detections, where there were an average of 8 detections for the 11 sample events. The average detection was 21ngL(-1) and its range was 1-245ngL(-1). 17beta-Estradiol was detected before manure was applied and also in the control plot lysimeters. Furthermore, the average mass recovery of E2 in all the lysimeters was >50%, which was greater than the FBA tracer recovery. Results indicated that tracer was transported with precipitated water infiltrating into the soil surface and percolating down through the soil profile. There was substantial evidence for antecedent E2, which was persistent and mobile. The persistence and mobility of the E2 may result from its associations with colloids, such as dissolved organic matter. Furthermore, this antecedent E2 appeared to overwhelm any observable effect of manure management on E2 fate and transport.

Fate of chlorate present in cattle wastes and its impact on Salmonella Typhimurium and Escherichia coli O157:H7.

Chlorate salts are being developed as a feed additive to reduce the numbers of pathogens in feedlot cattle. A series of studies was conducted to determine whether chlorate, at concentrations expected to be excreted in urine of dosed cattle, would also reduce the populations of pathogens in cattle wastes (a mixture of urine and feces) and to determine the fate of chlorate in cattle wastes. Chlorate salts present in a urine-manure-soil mixture at 0, 17, 33, and 67 ppm had no significant effect on the rates of Escherichia coli O157:H7 or Salmonella Typhimurium inactivation from batch cultures. Chlorate was rapidly degraded when incubated at 20 and 30 degrees C with half-lives of 0.1 to 4 days. Chlorate degradation in batch cultures was slowest at 5 degrees C with half-lives of 2.9 to 30 days. The half-life of 100 ppm chlorate in an artificial lagoon system charged with slurry from a feedlot lagoon was 88 h. From an environmental standpoint, chlorate use in feedlot cattle would likely have minimal impacts because any chlorate that escaped degradation on the feedlot floor would be degraded in lagoon systems. Collectively, these results suggest that chlorate administered to cattle and excreted in wastes would have no significant secondary effects on pathogens present in mixed wastes on pen floors. Lack of chlorate efficacy was likely due to low chlorate concentrations in mixed wastes relative to chlorate levels shown to be active in live animals, and the rapid degradation of chlorate to chloride at temperatures of 20 degrees C and above.

Destruction of estrogens using Fe-TAML/peroxide catalysis.

Endocrine disrupting chemicals (EDCs) impair living organisms by interfering with hormonal processes controlling cellular development Reduction of EDCs in water by an environmentally benign method is an important green chemistry goal. One EDC, 17alpha-ethinylestradiol (EE2), the active ingredient in the birth control pill, is excreted by humans to produce a major source of artificial environmental estrogenicity, which is incompletely removed by currenttechnologies used by municipal wastewater treatment plants (MWTPs). Natural estrogens found in animal waste from concentrated animal feeding operations (CAFOs) can also increase estrogenic activity of surface waters. An iron-tetraamidomacrocyclic ligand (Fe-TAML) activator in trace concentrations activates hydrogen peroxide and was shown to rapidly degrade these natural and synthetic reproductive hormones found in agricultural and municipal effluent streams. On the basis of liquid chromatography tandem mass spectrometry, apparent half-lives for 17 alpha- and 17 beta-estradiol, estriol, estrone, and EE2 in the presence of Fe-TAML and hydrogen peroxide were approximately 5 min and included a concomitant loss of estrogenic activity as established by E-Screen assay.

Discerning and modeling the fate and transport of testosterone in undisturbed soil.

Testosterone is an endocrine disruptor that is released into the environment from natural and anthropogenic sources. The objective of this study was to achieve a better understanding of the complex fate and transport of this labile compound in an undisturbed agricultural soil (a Hamar Sandy, mixed, frigid typic Endoaquolls). This was done by using batch and miscible-displacement experiments, and by using a chemical nonequilibrium transport model. Sorption and transformations of testosterone were discerned using various batch experiments. The batch experiments indicated that the aqueous phase concentrations of testosterone rapidly decreased from 12 to 15% of the initial aqueous concentration within 5 h, but then gradually increased through time and reached 28 to 29% of the initial aqueous concentration at 168 h. The increase in the aqueous concentration was explained by mineralization and biodegradation. Multiple first-order models were used to describe batch experiments where simultaneous degradation and sorption processes occurred. An evolutionary global optimization strategy was used to estimate the process parameters from these batch experiments and there was high confidence in these parameter estimates. The result of column experiments also showed that 23.4% of testosterone was mineralized to CO2 as it transported through the column. Combustion analyses of extracted soil from inside the columns showed that most of the 14C retained in the column (69-74%) was sorbed in the top 5 cm. The independently determined batch parameters were incorporated into a chemical nonequilibrium transport model, which provided an excellent description of the hormone in the effluent, and vertical redistribution in the soil column.

Persistence and fate of 17beta-estradiol and testosterone in agricultural soils.

Steroidal hormones are constantly released into the environment by man-made and natural sources. The goal of this study was to examine the persistence and fate of 17beta-estradiol and testosterone, the two primary natural sex hormones. Incubation experiments were conducted under aerobic and anaerobic conditions using [4-(14)C]-radiolabeled 17beta-estradiol and testosterone. The results indicated that 6% of 17beta-estradiol and 63% of testosterone could be mineralized to (14)CO(2) in native soils under aerobic conditions. In native soils under anaerobic conditions, 2% of testosterone and no 17beta-estradiol was methanogenized to (14)CH(4). Essentially, no mineralization of either testosterone or 17beta-estradiol to (14)CO(2) occurred in autoclaved soils under aerobic or anaerobic condition. Results also indicated that 17beta-estradiol could be transformed to an unidentified polar compound through abiotic chemical processes; however, 17beta-estradiol was only oxidized to estrone via biological processes. The TLC results also indicated that testosterone was degraded, not by physical-chemical processes but by biological processes. Results also indicated that the assumed risks of estrogenic hormones in the environment might be over-estimated due to the soil's humic substances, which can immobilize majority of estrogenic hormones, and thereby reduce their bioavailability and toxicity.

Tissue distribution, elimination, and metabolism of sodium [36Cl]perchlorate in lactating goats.

Perchlorate has contaminated water sources throughout the United States but particularly in the arid Southwest, an area containing large numbers of people and few water sources. Recent studies have demonstrated that perchlorate is present in alfalfa and that perchlorate is secreted into the milk of cows. Studies in lactating cows have indicated that only a small portion of a perchlorate dose could be accounted for by elimination in milk, feces, or urine. It was hypothesized that the remainder of the perchlorate dose was excreted as chloride ion. The purpose of this study was to determine the fate and disposition of (36)Cl-perchlorate in lactating dairy goats. Two goats (60 kg) were each orally administered 3.5 mg (16.5 muCi) of (36)Cl-perchlorate, a dose selected to approximate environmental perchlorate exposure but that would allow for adequate detection of radioactive residues after a 72 h withdrawal period. Blood, milk, urine, and feces were collected incrementally until slaughter at 72 h. Total radioactive residue (TRR) and perchlorate concentrations were measured using radiochemical techniques and liquid chromatography mass spectrometry (LC-MS-MS). Peak blood levels of TRR occurred at 12 h ( approximately 195 ppb) postdose; peak levels of parent perchlorate, however, occurred after only 2 h, suggesting that perchlorate metabolism occurred rapidly in the rumen. The serum half-life of perchlorate was estimated to be 2.3 h. After 24 h, perchlorate was not detectable in blood serum but TRR remained elevated (160 ppb) through 72 h. Milk perchlorate levels peaked at 12 h (155 ppb) and were no longer detectable by 36 h, even though TRRs were readily detected through 72 h. Perchlorate was not detectable in skeletal muscle or liver at slaughter (72 h). Chlorite and chlorate were not detected in any matrix. The only radioactive residues observed were perchlorate and chloride ion. Bioavailability of perchlorate was poor in lactating goats, but the perchlorate that was absorbed intact was rapidly eliminated in milk and urine.

Fate and transport of 1278-TCDD, 1378-TCDD, and 1478-TCDD in soil-water systems.

The most toxic dioxin is 2,3,7,8-tetrachlorodibenzo-p-dioxin (2378-TCDD), and obtaining comprehensive experimental data for this compound is challenging. However, several nontoxic isomers of 2378-TCDD exist, and can provide significant experimental evidence about this highly toxic dioxin. The goal of this study was to obtain experimental evidence for the fate and transport of 2378-TCDD in natural soils using its nontoxic isomers, 1,2,7,8-tetrachlorodibenzo-p-dioxin (1278-TCDD), 1,3,7,8-tetrachlorodibenzo-p-dioxin (1378-TCDD), and 1,4,7,8-tetrachlorodibenzo-p-dioxin (1478-TCDD). Batch sorption and miscible-displacement experiments, in various soils, were done using [4-(14)C]-radiolabeled TCDDs, while metabolism of these compounds was monitored. The results from the batch experiments indicated a high sorption affinity of all the TCDD isomers to soils and a strong correlation to organic matter (OM) content. 1278-TCDD, 1378-TCDD and 1478-TCDD (TCDDs) were more tightly bound to the soil with high OM than to the soil with low OM; however, it took a longer contact time to approach sorption equilibrium of TCDDs in the soil with high OM. Miscible-displacement breakthrough curves indicated chemical nonequilibrium transport, where there was a rate-limited or kinetic sorption that was likely caused by OM. Combustion analyses of extracted soil from the soil columns showed that most TCDDs were adsorbed in the top 1-5 cm of the column. These column combustion results also showed that sorption was correlated to specific surface and soil depth, which suggested the possibility of colloidal transport.

Polychlorinated dioxins, furans, and biphenyls, and polybrominated diphenyl ethers in a U.S. meat market basket and estimates of dietary intake.

Persistent environmental contaminants including polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs), non-ortho-polychlorinated biphenyls (PCBs), and polybrominated diphenyl ethers (PBDEs) were analyzed in 65 meat samples collected from supermarkets across the U.S. in 2001. The samples included hamburger, sirloin steaks, pork chops, bacon, and whole chickens from nine different cities. The average PCDD/F/non-ortho-PCB toxic equivalency (TEQ) for all the samples was 0.55 pg/g of lipid (nd (nondetect) = DL (detection limit)/2) with a range from nondetectable to 3.21 pg/g of lipid. For PBDEs, eight congeners were routinely found in the meat samples with an average sum of 1.71 ng/g of lipid (nd = DL/2) and a range from nondetectable to 16.6 ng/g of lipid. While average TEQs were similar to recent values reported in Europe and Asia, the sums of PBDEs in chicken and pork were 3-20 times higher than levels reported in Spain and Japan for these foods. The presence of a few outliers raised the average PBDE sums and indicated that isolated sources of contamination may exist that, if identified, could be removed from the U.S. animal production chain. Using these TEQ and PBDE values and USDA food consumption data, the estimated dietary intake ranges from meat products were 5.3-16.0 pg TEQ and 14.9-44.7 ng of PBDEs/d or 0.1-0.3 pg TEQ and 0.3-0.5 (ng of PBDEs/kg of body mass)/d for an average individual, similar to intakes in other countries.

Sorption, mobility, and transformation of estrogenic hormones in natural soil.

Potent estrogenic hormones are consistently detected in the environment at low concentration, yet these chemicals are strongly sorbed to soil and are labile. The objective of this research was to improve the understanding of the processes of sorption, mobility, and transformation for estrogens in natural soils, and their interaction. Equilibrium and kinetic batch sorption experiments, and a long-term column study were used to study the fate and transport of 17beta-estradiol and its primary metabolite, estrone, in natural soil. Kinetic and equilibrium batch experiments were done using radiolabeled 17beta-estradiol and estrone. At the concentrations used, it appeared that equilibrium sorption for both estrogens was achieved between 5 and 24 h, and that the equilibrium sorption isotherms were linear. The log K(oc) values for 17beta-estradiol (2.94) and estrone (2.99) were consistent with previously reported values. Additionally, it was found that there was rate-limited sorption for both 17beta-estradiol (0.178 h(-1)) and estrone (0.210 h(-1)). An approximately 42 h long, steady-flow, saturated column experiment was used to study the transport of radiolabeled 17beta-estradiol, which was applied in a 5.00 mg L(-1) solution pulse for 44 pore volumes. 17beta-estradiol and estrone were the predominant compounds detected in the effluent. The effluent breakthrough curves were asymmetric and the transport modeling indicated that sorption was rate-limited. Sorption rates and distributions of the estrogens were in agreement between column and batch experiments. This research can provide a better link between the laboratory results and observations in the natural environment.

Tissue distribution, elimination, and metabolism of dietary sodium [36Cl]chlorate in beef cattle.

Two steers (approximately 195 kg) were each dosed with 62.5 or 130.6 mg/kg body weight sodium [36Cl]chlorate for three consecutive days. All excreta were collected during the dosing and 8 h withdrawal periods. The apparent radiochlorine absorption was 62-68% of the total dose with the major excretory route being urine. Parent chlorate was 65-100% of the urinary radiochlorine; chloride was the only other radiochlorine species present. Similarly, residues in edible tissues were composed of chloride and chlorate with chloride being the major radiolabeled species present. Chlorate represented 28-57% of the total radioactive residues in skeletal muscle; in liver, kidney, and adipose tissues, chlorate ion represented a smaller percentage of the total residues. Chlorate residues in the low dose steer were 26 ppm in kidney, 14 ppm in skeletal muscle, 2.0 ppm in adipose tissue, and 0.7 ppm in liver. These data indicate that sodium chlorate may be a viable preharvest food safety tool for use by the cattle industry.

Fate and transport of testosterone in agricultural soils.

Hormones excreted in animal waste have been measured in surface and groundwater associated with manure that is applied to the land surface. Limited studies have been done on the fate and transport of androgenic hormones in soils. In this study, batch and column experiments were used to identify the fate and transport of radiolabeled [14C] testosterone in agricultural soils. The batch results indicated that aqueous-phase concentrations decreased for the first 5 h and then appeared to increase through time. The first-order sorption kinetics ranged from 0.08 to 0.640 h(-1) for the first 5 h. Beyond 5 h the increase in aqueous 14C could have been caused by desorption of testosterone back into the aqueous phase. However, metabolites were also produced beyond 5 h and would have likely resulted in the increase in aqueous 14C by sorption site competition and/or by lower sorption affinity. There were weak correlations of sorption with soil particle size, organic matter, and specific surface area. Testosterone was the dominant compound present in the soil column effluents, and a fully kinetic-sorption, chemical nonequilibrium model was used to describe the data. Column experiment sorption estimates were lower than the batch, which resulted from rate-limiting sorption due to the advective transport. The column degradation coefficients (0.404-0.600 h(-1)) were generally higher than values reported in the literature for 17beta-estradiol. Although it was found that testosterone degraded more readily than 17beta-estradiol, it appeared to have a greater potential to migrate in the soil because it was not as strongly sorbed. This study underlined the importance of the simultaneous transformation and sorption processes in the transport of hormones through soils.

Fate and transport of 17beta-estradiol in soil-water systems.

Over the past several years, there has been an increase in concern regarding reproductive hormones in the environment To date, there exists limited research on the fate and transport of these chemicals in the environment. In this study, a series of laboratory batch sorption and miscible-displacement experiments were done using radiolabeled [14C]17beta-estradiol. The 17beta-estradiol concentrations that were used were similar to those found in manures that are applied to field soils. Equilibrium batch experiments indicated high sorption affinity with correlations to mineral particle size and organic matter content. The sorption affinity appeared to be associated with the surface area and/or the cation-exchange capacity of the soil. The miscible-displacement breakthrough curves indicated chemical nonequilibrium transport, and a single highly polar metabolite was present in the column effluent along with sporadic and trace detections of estriol. Sorbed to the soil within the column were found 17beta-estradiol, estrone, and trace and sporadic detections of estriol. Two chemical nonequilibrium, miscible-displacement models were used to describe the column breakthrough curves; one without transformations and the other with transformations. Both models resulted in excellent descriptions of the data, which indicated nonunique solutions and less confidence in the parameter estimates. Nonetheless, the modeling and experimental results implied that degradation/transformation occurred in the sorbed phase and was rapid. Also, both models indicated that sorption was fully kinetic.