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The presence of natural estrogen hormones as trace concentrations in the environment has been reported by many researchers and is of growing concern due to its possible adverse effects on the ecosystem. In this study, municipal biosolids, poultry manure (PM) and cow manure (CM), and spent mushroom compost (SMC) were analyzed for the presence of seven estrogen hormones. 17α-estradiol, 17β-estradiol, 17α-dihydroequilin, and estrone were detected in the sampled biosolids and manures at concentrations ranging from 6 to 462 ng/g of dry solids. 17α-estradiol, 17β-estradiol, and estrone were also detected in SMC at concentrations ranging from 4 to 28 ng/g of dry solids. Desorption experiments were simulated in the laboratory using deionized water (milli-Q), and the aqueous phase was examined for the presence of estrogen hormones to determine their desorption potential. Very low desorption of 0.4% and 0.2% estrogen hormones was observed from municipal biosolids and SMC, respectively. An estimate of total estrogen contribution from different solid waste sources is reported. Animal manures (PM and CM) contribute to a significant load of estrogen hormones in the natural environment.  相似文献   
2.

The efficiency of four sample processing methods was tested with eight different types of soils representing the major proportion of cultivated soils. The principle of sampling constant was applied for characterizing the efficiency of the procedures and testing the well-mixed status of the prepared soil. The test material was 14C-labeled atrazine that enabled keeping the random error of analyses ≤ about 1%. Adding water to the soil proved to be the most efficient and generally applicable procedure resulting in about 6% relative sample processing uncertainty for 20 g test portions. The expected error is inversely proportional to the mass of test portion. Smashing and manual mixing of soil resulted in about four times higher uncertainty than mixing with water. Grinding of soil is applicable for dry soils only, but the test procedure applied was not suitable for estimating a typical uncertainty of processing dry soil samples. Adding dry ice did not improve the efficiency of sample processing.  相似文献   
3.
Cultured amniotic fluid cells from two mucolipidosis type IV (MLIV)-affected fetuses demonstrated accumulation of phospholipids and gangliosides when compared with normal controls. Like cultured skin fibroblasts from MLIV patients, cultured amniotic cells from the affected fetuses accumulated primarily lyso phospholipids and this could be demonstrated by radioactive labelling with appropriate precursors, either inorganic phosphate or oleic acid. Furthermore, like cultured skin fibroblasts, there was significant retention of exogenously supplied GDIA ganglioside in the affected amniotic cells. This storage was previously demonstrated to be unique to MLIV and thus can be used at present as a specific procedure for prenatal diagnosis of MLIV.  相似文献   
4.
Three municipal wastewater treatment plants (WWTPs) in southeastern Pennsylvania were sampled to determine the presence and concentrations of 12 natural and synthetic estrogen hormones in the wastewater influent and effluent. The target estrogens were 17alpha-estradiol, estrone, estriol, equilin, 17alpha-dihydroequilin, 17beta-estradiol, 17alpha-ethinyl estradiol, gestodene, norgestrel, levonorgestrel, medrogestone, and trimegestone. One WWTP uses a biofilm reactor (packed-bed trickling filter),and the other two use suspended-growth media (continuously stirred activated sludge reactor and sequential batch reactor). Estrone was detected in all the three plants; estriol and estradiol were detected at two WWTPs; and 17 alpha-dihydroequilin and 17 alpha-ethinyl estradiol were detected at one WWTP. The concentration of estrogens in the influent and effluent of the three treatment plants ranged from 1.2 to 259 ng/L and 0.5 to 49 ng/L, respectively. The percentage removal of estrogens from the aqueous phase ranged from 41 to 99%, except in the case of 17alpha-dihydroequilin; the removal of 17alpha-dihydroequilin was negligible. The suspended-growth media systems showed higher removal efficiencies for estrogens than the biofilm system. The analytical method uses a Varian C-18 solid-phase extraction (Varian Inc., Palo Alto, California), followed by a derivatization with bis(trimethylsilyl)trifluoroacetamide. The detection limits for the estrogen compounds ranged from 0.1 to 10 ng/L using a sample size of 1 L. The method recoveries ranged from 71 to 120%, and the relative standard deviation ranged from 6 to 14% for all the hormones.  相似文献   
5.
The occurrence of pharmaceutically active chemicals (PACs) in the natural aquatic environment is recognized as an emerging issue due to the potential adverse effects these compounds pose to aquatic life and humans. This study presents the monitoring of two major categories of PACs in surface water: steroid hormones and antibiotics. Surface water samples were collected in the fall season from 21 locations in suburban (4), agricultural (5) and mixed (12) use suburban and agricultural areas. The water samples collected were analyzed using GC/MS for aqueous concentration of eleven steroid hormones: six natural (17alpha-estradiol, 17beta-estradiol, estrone, estriol, 17alpha-dihydroequilin, progesterone) and five synthetic (gestodene, norgestrel, levonorgestrel, medrogestone, trimegestone). In addition, 12 antibiotics (oxytetracycline, chlorotetracycline, tetracycline, sulfamethoxazole, sulfamethazine, trimethoprim, lincomycin, norfloxacin, ofloxacin, roxithromycin, erythromycin, tylosin tartrate) were analyzed using LC/MS. Steroid hormones detected in surface water were: 17alpha-estradiol, 17beta-estradiol, 17alpha-dihydroequilin, estriol, estrone, progesterone and trimegestone. Estrone had the highest detection frequency of >90% with concentrations ranging from 0.6 to 2.6 ng/l. The second most frequently detected estrogen was estriol (>80%) with concentrations ranging from 0.8 to 19 ng/l. The detection frequency varied at different sampling locations. No antibiotics were detected in the 21 streams sampled. This study aims to give a better understanding on the presence, fate and transport of PACs derived from humans and animals.  相似文献   
6.
In this paper the results of a thorough evaluation of the environmental fate and effects of azilsartan are presented. Azilsartan medoxomil is administered as a pro-drug for the treatment of patients with essential hypertension. The pro-drug is converted by hydrolysis to the active pharmaceutical ingredient azilsartan. Laboratory tests to evaluate the environmental fate and effects of azilsartan medoxomil were conducted with azilsartan and performed in accordance with OECD test guidelines. The predicted environmental concentration (PEC) in surface water was estimated at 0.32 μg L−1 (above the action limit of 0.01 μg L−1), triggering a Phase II assessment. Azilsartan is not readily biodegradable. Results of the water sediment study demonstrated significant shifting of azilsartan metabolites to sediment. Based on the equilibrium partitioning method, metabolites are unlikely to pose a risk to sediment-dwelling organisms. Ratios of the predicted environmental concentrations (PECs) to the predicted-no-effect concentrations (PNECs) did not exceed the relevant triggers, and the risk to aquatic, sewage treatment plant (STP), groundwater and sediment compartments was concluded acceptable. A terrestrial assessment was not triggered. Azilsartan poses an acceptable risk to the environment.  相似文献   
7.
Simultaneous analysis of 11 free estrogen hormones and five conjugated estrogens in water and municipal wastewater was studied. The analytical method was developed and tested for different types of solid-phase extraction adsorbents, eluents, sample containers and storage conditions, derivatization, and matrix effects. Varian Bond Elut C-18 solid-phase extraction adsorbent cartridge was selected based on its high recoveries for both free and conjugated estrogens. Sample storage conditions, as well as selection and pretreatment of sample container materials, can affect the trace level analysis of estrogens. Silanization of glassware is observed to provide low relative standard deviation (RSD) in the analysis and less percentage loss due to contacting with sample container materials. Light exposure during the test can significantly impact the results. The derivatized samples stored at −20°C for at least 6 days showed less than 10.5% average RSD in the analysis. The recovery efficiency in clean water varies from 72% to 101% for free estrogens and 78% to 82% for conjugated estrogens. The method detection limits (MDL) for most of the compounds range from 30 to 870 ng/L using a sample volume of 200 mL. With a sample volume of 3 L, the most sensitive compound produces a MDL of 0.03 ng/L. Dilute methanol is used to wash the loaded cartridge as a cleanup step in order to remove interfering species during analysis of wastewater samples. Using the optimized analytical methods, the concentration level of free estrogens in the influent and effluent municipal wastewaters is tested.  相似文献   
8.
ABSTRACT

The overall objective of this pilot-scale study is to investigate the technical feasibility of the removal and destruction of organic contaminants in water using adsorption and photocatalytic oxidation. The process consists of two consecutive operational steps: (1) removal of organic contaminants using fixed-bed adsorption; and (2) regeneration of spent adsorbent using photocatalysis or steam, followed by decontamination of steam condensate using photocatalysis. The pilot-scale study was conducted to evaluate these options at a water treatment plant in Wausau (Wisconsin) for treatment of groundwater contaminated with tetrachloroethene (PCE), trichloroethene (TCE), cis-dichloroethene (cis-DCE), toluene, ethylbenzene (EB), and xylenes. The adsorbents used were F-400 GAC and Ambersorb 563.

In the first treatment strategy, the adsorbents were impregnated with photocatalyst and used for the removal of aqueous organics. The spent adsorbents were then exposed to ultraviolet light to achieve photocatalytic regeneration. Regeneration of adsorbents using photocatalysis was observed to be not effective, probably because the impregnated photocatalyst was fouled by background organic matter present in the groundwater matrix.

In the second treatment strategy, the spent adsorbents were regenerated using steam, followed by cleanup of steam condensate using photocatalysis. Four cycles of adsorption and three cycles of steam regeneration were performed. Ambersorb 563 adsorbent was successfully regenerated using saturated steam at 160 °C within 20 hours. The steam condensate was treated using fixed-bed photo-catalysis using 1% Pt-TiO2 photocatalyst supported on silica gel. After 35 minutes of empty bed contact time, more than 95% removal of TCE, cis-DCE, toluene, EB, and xylenes was achieved, and more than 75% removal of PCE was observed.

In the case of activated carbon adsorbent, steam regeneration was not effective, and a significant loss in adsorbent capacity was observed.  相似文献   
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