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Concerns regarding man‐made organic chemicals pervading our ecosystem and having adverse and detrimental effects upon organisms, including man, have now been studied for several decades. Since the 1970s, some environmental pollutants were identified as having endocrine disrupting affects. These endocrine disrupting chemicals (EDC) were initially shown to have estrogenic or anti‐estrogenic properties and some were also shown to bind to a variety of hormone receptors. However, since the 1990s it has also been identified that many of these EDC additionally, have the ability of causing abnormal alterations in Ca2+ signalling pathways (also commonly involved in hormone signalling), leading to exaggerated elevations in cytosolic [Ca2+] levels, that is known to cause activation of a number of cell death pathways. The major emphasis of this review is to present a personal perspective of the evidence for some types of EDC, specifically alkylphenols and brominated flame retardants (BFRs), causing direct effects on Ca2+ transporters (mainly the SERCA Ca2+ ATPases), culminating in acute cytotoxicity and cell death. Evidence is also presented to indicate that this Ca2+ATPase inhibition, which leads to abnormally elevated cytosolic [Ca2+], as well as a decreased luminal ER [Ca2+], which triggers the ER stress response, are both involved in acute cytotoxicity. [ABSTRACT FROM AUTHOR]

Endocrine‐disrupting compounds (EDCs) such as natural and synthetic hormones as well as phenolic industrial chemicals are considered contaminants of emerging concern in environmental waters. While EDCs carried through rivers may impact ecosystem health and productivity, these compounds are still not widely studied nor regulated. In the present study, we report the occurrence of EDCs in urban rivers in Mega Manila, namely, the Marikina, Pasig, Angat, and Pampanga Rivers that drain into Manila Bay. Endocrine‐disrupting compounds may have reached these rivers through domestic wastewater and industrial effluents. Water samples from the rivers were extracted by solid‐phase extraction before instrumental analysis using a liquid chromatograph coupled to a mass spectrometer. The analytical method exhibited good linear response (>99% in the concentration range of 1–50 µg/L) and low instrument detection limits (0.14–1.46 µg/L) for the hormones estrone (E1), estradiol, ethinylestradiol, progesterone, and testosterone, and the industrial chemicals bisphenol A, nonylphenol, and octylphenol. Of the hormones, E1 was detected up to 11 ng/L. Bisphenol A, nonylphenol, and octylphenol were measured up to 54, 1878, and 62 ng/L, respectively. Endocrine‐disrupting compounds are not yet monitored in water bodies in the Philippines and there are no local guidelines yet on occurrence, pollution prevention, and mitigation. Environ Toxicol Chem 2024;43:259–266. © 2023 SETAC [ABSTRACT FROM AUTHOR]

Lignin can be converted into useful precursors of fuels and fine chemicals by thermochemical conversion followed by catalytic hydrogenation using metal catalysts at severe reaction conditions. Thus, mild hydrogenation would significantly improve the sustainability of lignin valorization. Here, hydrogenation of phenols, alkylphenols, and methoxyphenols was achieved at mild reaction conditions (70 °C and atmospheric pressure) via H‐transfer hydrogenation over Raney‐Ni catalyst in 2‐propanol and 2‐butanol solvents. The transfer hydrogenation was feasible at the mild conditions, but the complexity of the reactant greatly decreased or even completely suppressed its reactivity. The position of the functional group (o‐, m‐, p‐position) had a great effect on the reactivity of phenols. Moreover, 2‐butanol enhanced the conversion of phenols in comparison with 2‐propanol. When comparing classic hydrogenation with H‐transfer hydrogenation in presence of external H2, it was found that external H2 not only regenerated H‐donor solvent and ensured stable performance but also increased conversion of phenols and alkylphenols. On the other hand, the absence of external H2 boosted the conversion of methoxy phenols. Finally, phenols extracted from a pyrolysis oil aqueous phase were hydrogenated. The conversion of phenols was greatly affected by competitive adsorption of different compounds present in the reaction mixture. External H2 promoted hydrogenation of the complex reaction mixture and prevented condensation of the reactive species in contrast to the H‐transfer hydrogenation. [ABSTRACT FROM AUTHOR]

The growth and morphology of rumen methanogenic archaea (15 strains of 10 species in 5 genera, including 7 strains newly isolated in the present study) and bacteria (14 species in 12 genera) were investigated using unsupplemented in vitro pure cultures and cultures supplemented with cashew nut shell liquid (CNSL) and its phenolic compound components, anti-methanogenic agents for ruminant animals. Growth of most of the methanogens tested was inhibited by CNSL and alkylphenols at different concentrations ranging from 1.56 to 12.5 µg/ml. Of the alkylphenols tested, anacardic acid exhibited the most potent growth inhibition. Three gram-negative bacterial species involved in propionate production were resistant to CNSL and alkylphenols (>50 µg/ml). All the methanogens and bacteria that were sensitive to CNSL and alkylphenols exhibited altered morphology; disruption of the cell surface was notable, possibly due to surfactant activity of the tested materials. Cells division was inhibited in some organisms, with cell elongation and unclear septum formation observed. These results indicate that CNSL and alkylphenols, particularly anacardic acid, inhibit both rumen bacteria and methanogens in a selective manner, which could help mitigate rumen methane generation. [ABSTRACT FROM AUTHOR]

Bisphenol A (BPA) and 4‐cumylphenol (4‐CP), as estrogen‐like chemicals, are ubiquitous in the environment media and associated with the occurrence and development of hormone‐dependent tumors. However, the combinatorial effects of these two structurally similar alkylphenols are not well informed. In the present study, the classic breast cancer cell line MCF‐7 was used as in vitro model to estimate the estrogenic proliferative effects of BPA and 4‐CP. MTT assay, reactive oxygen species, cell apoptosis, cell cycle, and real‐time fluorescent quantitative Step One Plus Real‐time PCR System (Applied Biosystems, CA, USA) were applied to explore their proliferative mechanisms. MTT results showed that both BPA and 4‐CP ranging from 10−9 to 10−5 M stimulated cell proliferation in a nonmonotonic dose‐response manner. Along with the proliferative effects, cell cycle was progressed from G0/G1 to S and G2/M phase. Meanwhile, the expression levels of ERα, pS2, and Bcl‐2 mRNA were also upregulated. In contrast, 4‐CP and BPA at high dose (10−4 M) obviously displayed antiproliferative effects in MCF‐7 cells via inducing cell apoptosis and blocking cell cycle in G0/G1 phase. As expected, the relative expression levels of ERα, pS2, and Bcl‐2 mRNA were decreased, whereas Bax mRNA was increased. Interestingly, the proliferative or antiproliferative effects of 4‐CP were higher than that of BPA. Moreover, coexposure of lower concentrations BPA and 4‐CP significantly induced cell proliferation in a synergistic manner. These findings indicated that the potential environmental risks of coexposure of BPA and 4‐CP were greater than either of them. [ABSTRACT FROM AUTHOR]

ABSTRACT: A polymer‐supported Fe(III) complex of 1,3‐bis(benzimidazolyl)benzene [PS–Fe(III)BBZNH] was used in the photodegradation of xylenol orange (XO) dye with H2O2 under UV irradiation. The catalyst was synthesized and characterized by elemental analysis, and Fourier transform infrared, far‐infrared, and UV–visible–diffuse reflectance spectroscopy, Scanning electron microscopy, Brunauer–Emmett–Teller surface area measurements, thermogravimetric analysis, and magnetic measurements. An octahedral coordination around Fe(III) was confirmed by electronic spectral data, and a decrease in the intensity of the νCH2Cl peak in PS–Fe(III)BBZNH was observed compared to the polymer support; this indicated the binding of the ligand to the support. An array of experiments were carried out to assess the influence of various reaction parameters on its photocatalytic performance to ensure maximum dye degradation. The maximum photocatalytic activity was observed at pH 8 with 125 mg of catalyst, 300 ppm of XO, and 200 ppm of H2O2 with complete mineralization after 90 min, as confirmed by chemical oxygen demand measurements. Furthermore, the reactions were repeated under sunlight and under dark conditions to check the photocatalytic efficiency of PS–Fe(III)BBZNH. It displayed better catalytic performance compared than the unsupported complex, PS–Cu(II)BBZNH [Cu(II) complex of 1,3‐bis(benzimidazolyl)benzene], and PS–VO(IV)BBZNH [VO(IV) complex of 1,3‐bis(benzimidazolyl)benzene]. PS–Fe(III)BBZNH could be recycled for up to seven runs. A tentative mechanism involving ·OH radical was proposed. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 46480. [ABSTRACT FROM AUTHOR]

Abstract: The enantioselective oxyfunctionalisation of C−H bonds is a highly interesting reaction, as it provides access to chiral alcohols that are important pharmaceutical building blocks. However, it is hard to achieve using traditional methods. One way in which it can be achieved is through the action of oxidative enzymes. Although many reports of the oxyfunctionalisation capabilities of enzymes at an analytical scale have been published, reports on the use of enzymes to achieve oxyfunctionalisation on a synthetically relevant scale are fewer. Here, we describe the scale‐up of the conversion of 4‐ethylphenol to (R)‐1‐(4′‐hydroxyphenyl)ethanol using the flavin‐dependent enzyme vanillyl alcohol oxidase. The process was optimised by testing different reaction media and substrate and enzyme concentrations and by performing it under an oxygen atmosphere. Under optimised reaction conditions, 4.10 g (R)‐1‐(4′‐hydroxyphenyl)ethanol at 97% ee was obtained from 10 g 4‐ethylphenol (isolated yield 36%). These results highlight some of the challenges that can be encountered during scale‐up of an enzymatic oxyfunctionalisation process to a synthetically relevant scale and will be of use for the development of enzymatic processes for the synthesis of industrially relevant compounds. [ABSTRACT FROM AUTHOR]

There are several established approaches for the reductive fractionationof lignocellulose (e.g., “catalytic upstream biorefining" and “lignin-first" approaches) that lead to a lignin oil product that is composed primarily of dihydro-p-monolignols [e.g., 4-(3-hydroxypropyl)-2-methoxyphenol and 4-(3-hydroxypropyl)- 2,6-dimethoxyphenol]. Although effective catalytic methods have been developed to perform reductive or deoxygenativeprocesses on the lignin oil, the influence of the 3-hydroxypropylsubstituent on catalyst activity has previously beenoverlooked. Herein, to better understand the reactivity of thedepolymerized lignin oil obtained from catalytic upstream biorefiningprocesses, dihydro-p-coumaryl alcohol was selected asa model compound. Hydrogenation of this species in the presenceof Raney Ni with molecular hydrogen led to ring saturation(100% selectivity) in the absence of hydrodeoxygenation,whereas under hydrogen-transfer conditions with 2-propanol,hydrogenation occurred (&55% selectivity) simultaneouslywith hydrodeoxygenation (&40% selectivity). In a broadercontext, this study sheds light not only on the reactivity of dihydro-p-monolignols but also on the intricacies of the catalyticupstream biorefining reaction network in which these speciesare revealed to be key intermediates in the formation of less functionalized p-alkylphenols. [ABSTRACT FROM AUTHOR]

Endocrine-disrupting chemicals present in the environment can bring about hormonal imbalance and be potentially harmful to the human health. Alkylphenols are omnipresent in the environment as they are constituents of several products. The aim of this study was to evaluate the effect of exogenous melatonin treatment on nonylphenol ( NP)-induced oxidative stress and testicular toxicity in Wistar rats using biochemical and histopathological parameters. The oxidative stress biomarkers, activities of enzymatic and non-enzymatic antioxidants and histopathological evaluation were performed in testicular tissues. NP caused elevated TBARS levels and marked alteration of both nonenzymatic and enzymatic biomarkers. Furthermore, severe histopathological alterations were observed in the testis of NP-exposed animals as compared with that of the control rats. Melatonin supplementation ameliorated the alterations in these biochemical and histopathological variables in rats. In conclusion, our results demonstrated that melatonin through its antioxidant activity effectively protected against the NP-induced testicular toxicity. [ABSTRACT FROM AUTHOR]

A simple and efficient hydrodeoxygenation strategy is described to selectively generate and separate high-value alkylphenols from pyrolysis bio-oil, produced directly from lignocellulosic biomass. The overall process is efficient and only requires low pressures of hydrogen gas (5 bar). Initially, an investigation using model compounds indicates that MoC x/C is a promising catalyst for targeted hydrodeoxygenation, enabling selective retention of the desired Ar−OH substituents. By applying this procedure to pyrolysis bio-oil, the primary products (phenol/4-alkylphenols and hydrocarbons) are easily separable from each other by short-path column chromatography, serving as potential valuable feedstocks for industry. The strategy requires no prior fractionation of the lignocellulosic biomass, no further synthetic steps, and no input of additional (e.g., petrochemical) platform molecules. [ABSTRACT FROM AUTHOR]

ABSTRACT Nonylphenol and short-chain nonylphenol ethoxylates such as NP2EO are present in aquatic environment as wastewater contaminants, and their toxic effects on aquatic species have been reported. Apoptosis has been shown to be induced by serum deprivation or copper treatment. To understand the toxicity of nonylphenol diethoxylate, we investigated the effects of NP2EO on apoptosis induced by serum deprivation and copper by using PC12 cell system. Nonylphenol diethoxylate itself showed no toxicity and recovered cell viability from apoptosis. In addition, nonylphenol diethoxylate decreased DNA fragmentation caused by apoptosis in PC12 cells. This phenomenon was confirmed after treating apoptotic PC12 cells with nonylphenol diethoxylate, whereas the cytochrome c release into the cytosol decreased as compared to that in apoptotic cells not treated with nonylphenol diethoxylates. Furthermore, Bax contents in apoptotic cells were reduced after exposure to nonylphenol diethoxylate. Thus, nonylphenol diethoxylate has the opposite effect on apoptosis in PC12 cells compared to nonylphenol, which enhances apoptosis induced by serum deprivation. The difference in structure of the two compounds is hypothesized to be responsible for this phenomenon. These results indicated that nonylphenol diethoxylate has capability to affect cell differentiation and development and has potentially harmful effect on organisms because of its unexpected impact on apoptosis. © 2015 Wiley Periodicals, Inc. Environ Toxicol 31: 1389-1398, 2016. [ABSTRACT FROM AUTHOR]

Proteomics was used in the calanoid copepod Eurytemora affinis for screening of protein expression modifications induced by organic contaminants. The copepods were exposed in a continuous flow-through system for 86 h to environmentally relevant concentrations of contaminants representative of the pollution in the Seine Estuary (Haute-Normandie, France; diuron, 500 ng L−1; alkylphenol mixture, 1000 ng L−1). Proteome analysis of whole-body copepod extracts by 2-dimensional gel electrophoresis revealed that the contaminants induced modifications in protein expression, with the highest quantitative variations occurring after diuron exposure. Specifically, 88 and 41 proteins were differentially expressed after diuron and alkylphenol treatments, respectively. After mass spectrometry analysis, 51 (diuron exposure) and 15 (alkylphenol exposure) proteins were identified. The identified proteins were potentially related to energy metabolism, cell growth, nervous signal conductivity, excitotoxicity, oxidative stress response, and antioxidant defense. The data suggest a massive general disturbance of physiological functions of E. affinis after diuron exposure, whereas alkylphenols induced an alteration of a few targeted physiological functions. The protein expression signatures identified after contaminant exposure deserve further investigation in terms of the development of novel potential biomarkers for water quality assessment. Environ Toxicol Chem 2016;35:1860-1871. © 2015 SETAC [ABSTRACT FROM AUTHOR]

By the combination of solid-phase extraction as well as isotope dilution gas chromatography with mass spectrometry, a sensitive and reliable method for the determination of endocrine-disrupting chemicals including bisphenol A, 4-octylphenol, and 4-nonylphenol in vegetable oils was established. The application of a silica/ N-( n-propyl)ethylenediamine mixed solid-phase extraction cartridge achieved relatively low matrix effects for bisphenol A, 4-octylphenol, and 4-nonylphenol in vegetable oils. Experiments were designed to evaluate the effects of derivatization, and the extraction parameters were optimized. The estimated limits of detection and quantification for bisphenol A, 4-octylphenol, and 4-nonylphenol were 0.83 and 2.5 μg/kg, respectively. In a spiked experiment in vegetable oils, the recovery of the added bisphenol A was 97.5-110.3%, recovery of the added 4-octylphenol was 64.4-87.4%, and that of 4-nonylphenol was 68.2-89.3%. This sensitive method was then applied to real vegetable oil samples from Zhejiang Province of China, and none of the target compounds were detected. [ABSTRACT FROM AUTHOR]

This article deals with the synthesis of new bio-based epoxy foams from the reaction between cardanol-derived epoxy compounds and vegetable oil-derived diamines. Cardanol is a natural alkylphenol obtained from Cashew Nut Shell Liquid (CNSL), an abundant non-edible by-product of the cashew nutshell industry. Curing of epoxy monomers proceeded by reaction with Priamine 1073 diamine. Poly(methylhydrogenosiloxane) was used as blowing agent in order to expand epoxy material. Bio-based epoxy foams were formulated with different amounts of blowing agent and were characterized by scanning electron microscopy, dynamic mechanical analysis, thermal analysis, and by measurement of their apparent density. The foams exhibited good thermal stability above 210°C and glass transition temperatures around 20°C. Obtained materials can be considered as promising low cost and environmentally friendly foams for structural applications. Practical applications: The reactant described in this article, i.e., epoxidized cardanol from CNSL, provides bio-based aromatic building blocks for further epoxy foam syntheses by reaction with vegetable oil-derived amine and blowing agent. The obtained rigid epoxy foams are partially bio-based and may be applied as shock, thermal and vibration insulation, and for the production of lightweight materials for the transportation industry such as aircraft-interior panels and crash pads. This paper proposes new epoxy foams from cardanol epoxy and fatty amines. [ABSTRACT FROM AUTHOR]

The interest in the analysis of alkylphenols (APs) has widely increased in the last decades because of the endocrine disrupting features of these phenol derivatives. However, the isolation and identification of many of the multiple chemical structures of all APs is a very challenging task because of their similar physicochemical properties. In this work, the co-elution of the isomers present in technical mixtures and using comprehensive two-dimensional gas chromatography coupled to quadrupole mass spectrometry was resolved using multivariate curve resolution-alternating least squares algorithm. The mass spectrum of each resolved compound was compared with the theoretical mass spectrum obtained from the literature, in order to assign the appropriate identification of each isomer. Two commercial mixtures were studied; in one of them, 34 compounds were resolved, and in the second mixture, 40 compounds were resolved. The relative abundances of the compounds were also calculated in both mixtures. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Large prosomal scent glands constitute a major synapomorphic character of the arachnid order Opiliones. These glands produce a variety of chemicals very specific to opilionid taxa of different taxonomic levels, and thus represent a model system to investigate the evolutionary traits in exocrine secretion chemistry across a phylogenetically old group of animals. The chemically best-studied opilionid group is certainly Laniatores, and currently available chemical data allow first hypotheses linking the phylogeny of this group to the evolution of major chemical classes of secretion chemistry. Such hypotheses are essential to decide upon a best-fitting explanation of the distribution of scent-gland secretion compounds across extant laniatorean taxa, and hence represent a key toward a well-founded opilionid chemosystematics. [ABSTRACT FROM AUTHOR]

General anesthetics have previously been shown to bind mitochondrial VDAC. Here, using a photoactive analog of the anesthetic propofol, we determined that alkylphenol anesthetics bind to Gly56 and Val184 on rat VDAC1. By reconstituting rat VDAC into planar bilayers, we determined that propofol potentiates VDAC gating with asymmetry at the voltage polarities; in contrast, propofol does not affect the conductance of open VDAC. Additional experiments showed that propofol also does not affect gramicidin A properties that are sensitive to lipid bilayer mechanics. Together, this suggests propofol affects VDAC function through direct protein binding, likely at the lipid-exposed channel surface, and that gating can be modulated by ligand binding to the distal ends of VDAC β-strands where Gly56 and Val184 are located. [ABSTRACT FROM AUTHOR]

This study tested the hypotheses that (1) exposure to treated Water Reclamation Plant ( WRP) effluent will induce biological effects in exposed fish that are consistent with environmental estrogen ( EE) exposure; and (2) seasonal differences in effluent composition will moderate biological effects. We conducted seven on-site exposures using a mobile laboratory. Total estrogenicity of effluents was 10- to 20-fold higher during spring than in fall. Common EEs including steroid estrogens, alkylphenols, and bisphenol-A were ubiquitous. An unusual spike in total estrogenicity identified a combined sewer overflow event. Fathead minnows ( Pimephales promelas) responded to exposure with subtle changes in vitellogenin concentrations and secondary sex characteristics. An opportunity to assess a common carp ( Cyprinus carpio) population permanently sustained inside the Stickney WRP revealed pronounced exposure effects, but also the resilience of biological organisms even under long-term exposure. In contrast to other studies, no histopathological changes were found. The mobile exposure laboratory proved capable of maintaining U.S. Environmental Protection Agency-recommended exposure conditions while providing flexibility for rapid deployment at multiple sites with minimal operational disruption. Further studies using this platform hold promise to resolve the convoluted interactions between complex effluents and inherent biological complexity. [ABSTRACT FROM AUTHOR]

Alkylphenolic chemicals (APCs) and hormones were measured six times from February through October 2007 in three Minnesota streams receiving wastewater to identify spatial and temporal patterns in concentrations and in estrogen equivalency. Fish were collected once during the study to evaluate endpoints indicative of endocrine disruption. The most commonly detected APCs were 4- tert-octylphenol and 4-nonylphenol and the most commonly detected hormones were estrone and androstenedione. Chemical concentrations were greatest for nonylphenol ethoxycarboxylates (NPECs) (5,000-140,000 ng/l), followed by 4-nonlylphenol and 4-nonylphenolethoxylates (50-880 ng/l), 4- tert-octylphenol and 4- tert-octylphenolethoxylates with concentrations as great as 130 ng/l, and hormones (0.1-54 ng/l). Patterns in chemicals and estrogen equivalency indicated that wastewater effluent is a pathway of APCs and hormones to downstream locations in this study. However, upstream contributions can be equally or more important indicating alternative sources. This study indicates that aquatic organisms experience both spatially and temporally variable exposures in the number of compounds, total concentrations, and estrogenicity. This variability was evident in fish collected from the three rivers as no clear upstream to downstream pattern of endocrine disruption endpoints emerged. [ABSTRACT FROM AUTHOR]

The titanium-based metal-organic framework MIL-125 and its amine-functionalized analog, MIL-125_NH2, have been synthesized and characterized by elemental analysis, XRD, SEM, TEM, N2 adsorption measurements, and spectroscopic techniques, including FTIR, Raman, and DR UV/Vis spectroscopy. Catalytic properties of MIL-125 and MIL-125_NH2 were evaluated in the selective oxidation of two representative alkyl-substituted phenols, 2,3,6-trimethylphenol and 2,6-di- tert-butylphenol, with the clean oxidant H2O2. With both MIL-125 and MIL-125_NH2, the selectivity toward the corresponding p-benzoquinones was 100 %. Samples of MIL-125 with different sizes of crystallites (0.5, 1.5, and 5 μm) demonstrated similar reaction rates, thus indicating the absence of diffusion limitations. The efficiency of the oxidant utilization and stability of the MIL-125 structure increased upon decreasing the amount of water in the reaction mixture. Even if the structural integrity of MIL-125 was destroyed by the reaction medium, the metal-organic framework acted as a precursor for the highly active, selective, and recyclable catalyst. The MIL-125-derived materials were stable toward titanium leaching, behaved as true heterogeneous catalysts, and could easily be recovered by filtration and reused several times without the loss of the catalytic properties. [ABSTRACT FROM AUTHOR]

An analytical platform was developed for the detection of biomass oxygenates and biocarbon in biogasoline produced by coprocessing of hydrodeoxygenated pyrolysis oils (HDO-oil) and vacuum gas oil. A combination of different analytical techniques is necessary for analyzing such complex mixtures. The presence of various oxygenated compounds such as alcohols, acids, and phenols was quantified using phosphorus nuclear magnetic resonance spectroscopy. Different alkylphenols were identified using two-dimensional gas chromatography-mass spectrometry. The transformations of lignin oligomers present in HDO-oil were determined with size-exclusion chromatography carried out for the products. Accelerator mass spectrometry was used to make the distinction between carbonaceous material of biological origin and that of fossil origin. This type of analytical platform, which is tailored for bio-oil identification and quantification, appears to be required for exploratory catalyst research and kinetic studies in this rapidly expanding domain. © 2011 American Institute of Chemical Engineers Environ Prog, 32: 377-383, 2013 [ABSTRACT FROM AUTHOR]

A rapid and solvent-free procedure for the determination of 4- tert-octylphenol and 4-nonylphenol isomers in aqueous samples is described. The method involves in-situ acetylation and microwave-assisted headspace solid-phase microextraction prior to their determination using gas chromatography-ion trap mass spectrometry operated in the selected ion storage mode. The dual experimental protocols to evaluate the effects of various derivatization and extraction parameters were investigated and the conditions optimized. Under optimized conditions, 300 μL of acetic anhydride mixed with 1 g of potassium hydrogencarbonate and 2 g of sodium chloride in a 20 mL aqueous sample were efficiently extracted by a 65 μm polydimethylsiloxane-divinylbenzene fiber that was located in the headspace when the system was microwave irradiated at 80 W for 5 min. The limits of quantitation were 5 and 50 ng/L for 4- tert-octylphenol and 4-nonylphenol isomers, respectively. The precision for these analytes, as indicated by relative standard deviations, were less than 8% for both intra- and inter-day analysis. Accuracy, expressed as the mean extraction recovery, was between 74 to 88%. A standard addition method was used to quantitate 4- tert-octylphenol and 4-nonylphenol isomers, and the concentrations ranged from 120 to 930 ng/L in various environmental water samples. [ABSTRACT FROM AUTHOR]

Degradation of alkylphenol ethoxylates to more persistent alkylphenols such as nonylphenol occurs in wastewater treatment plants where nonylphenol is released to aquatic systems. In this study, acute and chronic tests were conducted to determine the toxicity and bioconcentration of nonylphenol to freshwater organisms for use in deriving national water quality criteria. Acute median effect concentrations (EC50s) based on loss of equilibrium, immobility, and lethality for species representing several taxonomic groups ranged from 21 to 596 µg/L. The EC50s were up to a factor of 2 less than median lethal concentrations (LC50s) and decreased with time over the test periods of 24 to 96 h. In chronic tests, early life stages of rainbow trout were 14 times more sensitive to nonylphenol than in acute tests and approximately 20 times more sensitive than Daphnia magna exposed over their complete life cycle. Comparisons of chronic test endpoints showed that 20% effect concentrations (EC20s), determined by regression testing, and chronic values, determined by hypothesis testing, were similar for both the rainbow trout and Daphnia magna. The lowest mean tissue–effect concentrations of nonylphenol appeared to be greater for the fathead minnow than bluegill, and ranged from approximately 130 to 160 µg/g after 96-h exposure and from approximately 20 to 90 µg/g after 28-d exposure. Mean lipid normalized bioconcentration factors (BCFs) associated with no-effect concentrations were approximately 180 and 50 for the fathead minnow and bluegill, respectively. The present test results suggest that long-term exposures to nonylphenol at concentrations found in some surface waters could adversely impact sensitive components of freshwater communities. Environ. Toxicol. Chem. 2010;29:2104–2111. © 2010 SETAC [ABSTRACT FROM AUTHOR]

Semipermeable membrane devices (SPMD) and polar organic chemical integrative samplers (POCIS) were exposed to a cocktail of organic chemicals using a flow-through system. Samplers were removed and analyzed every 7 d over a four-week period in order to determine sampling rates (Rs) for individual compounds. Prior to laboratory exposure, half of the samplers were allowed to foul naturally for six weeks, in order to examine differences in uptake due to fouling. The amount of fouling ranged from 0.2 to 2.8 g dry weight/dm2 for POCIS and 0.1 to 1.4 g dry weight/dm2 for SPMDs, and the pattern of accumulation was also different between them. The Rs values were determined by fitting curves to time course uptake data and also by using performance reference compounds (PRCs) for SPMDs. Sampling rates ranged from 2.7 to 14.2 L/d for SPMDs and 0.01 to 0.27 L/d for POCIS. Fouled SPMDs showed a reduction in Rs (<20%) for all but one compound, and there was a similar reduction in the release of PRCs. However, PRC-predicted Rs values were overall somewhat higher than those from fitted curves. Uptake of alkylated phenols in POCIS was generally higher (up to 55%) in fouled samplers. The reason for this is not known, but is possibly due to some reduction in interactions with the membrane in fouled samplers. There was no overall pattern in the relationship of sampling rate differences with log KOW or over time for either sampler. Release of compounds from POCIS after a drop in exposure water concentrations provides some encouragement for the application of a PRC approach to polar passive samplers. [ABSTRACT FROM AUTHOR]

The fate and removal of the estrogens 17β-estradiol (E2), estrone (E1), and 17α-ethynylestradiol (EE2) and of the xenoestrogens bisphenol A (BPA), 4-tert-octylphenol (4-t-OP), 4-nonylphenol (4-NP), and nonylphenol mono- and diethoxylate (NPEO1 and NPEO2, respectively) were investigated in four South Australian sewage treatment plants (STPs; plants A-D) with different treatment technologies. The concentrations in the effluent from the two-year survey were similar to those reported in other studies. In the effluent, 4-NP, NPEO1, and NPEO2 had total concentrations up to 8 μg/L, which were much higher than those of BPA and 4-t-OP. Estrone had the highest concentrations among the three estrogens, ranging between 13.3 and 39.3 ng/L, whereas the concentrations for E2 and EE2 varied between 1.0 and 4.2 ng/L and between 0.1 and 1.3 ng/L, respectively. The removal rates for the estrogens and xenoestrogens were variable but consistent with the plant performance parameters (biochemical oxygen demand, suspended solids, and ammonia). Considering all the estrogenic compounds analyzed in the present study, plant D, with a series of anaerobic and aerobic lagoons, was the least efficient of the four STPs in the removal of these compounds. The removal rates for 4-NP, NPEO1, and NPEO2 within the plants were 92% for plant A, with conventional activated sludge treatment; 80% for plant B, with two oxidation ditches; 70% for plant C, with three bioreactors; and 64% for plant D, with 10 lagoons in series. Comparatively, the removal of estrogens was lower, with rates ranging between 47 and 68% for E2 at the four plants. Both E1 and EE2 were more persistent during treatment, especially in plants C and [ABSTRACT FROM AUTHOR]

Toxicity and endocrine interference of influent and effluent waters from domestic and industrial wastewater treatment plants were determined. In addition, chemical analyses were performed to detect the presence of 17β-estradiol, 17α-ethinyl estradiol, nonylphenol, 4-octylphenol, and p-t-octylphenol as well as lead, copper, and cadmium in these matrices. The results showed that despite low acute toxic potential, most of the samples tested showed both genotoxicity and endocrine interference. Furthermore, to establish whether the observed effects were caused by the alkylphenols and the heavy metals detected, toxic, genotoxic, and endocrine interference tests also were performed on pure chemicals. The acute toxicity was measured on the crustacean Daphnia magna. The estrogenic activity was determined by using the yeast estrogen screen with Saccharomyces cerevisiae RMY326, whereas the SOS Chromotest and Ames test detected the genotoxicity on Escherichia coli PQ37 and Salmonella typhimurium TA98 and TA100, respectively. The results showed that the toxicity found in the matrices did not match the values found for pure chemicals, but a clear correlation was found between alkylphenols and genotoxicity. Both heavy metals and alkylphenols took part in the endocrine interference activity. [ABSTRACT FROM AUTHOR]

As a result of the introduction of tighter discharge limits and effluent treatment processes at source, the concentration of alkylphenol ethoxylates and nonylphenol present in the final effluent discharge from a sewage treatment works that treats trade effluent from the textiles industry was reduced. The estrogenic effects of the final effluent discharge to the Aire River were compared over a four-year period during which various treatment measures were introduced. Male rainbow trout exposed to the effluent on four occasions in consecutive years (1994-1997) showed a reduction in the level of induced vitellogenesis between 1994 and 1997. A marked decrease in gonadosomatic index (GSI) and increase in heptaosomatic index (HSI) was measured in fish exposed to the effluent in 1994. In successive years, these differences diminished, and in the case of the GSI no measurable difference was observed between fish exposed to the final effluent or those in the control group in 1997. However, an increase in HSI was still measurable in 1997 in fish exposed to the final effluent and at sites farther downstream. The reduction in the effects of the effluent paralleled the reduction in the concentration of nonylphenol as well as its mono- and diethoxylates, which have been demonstrated to produce estrogenic effects in trout exposed to these compounds in the laboratory. This study demonstrates that the setting of more restricted discharge limits for known estrogenic chemicals of industrial origin can lead to significant reductions in the estrogenic activity of the watercourses into which the effluents are discharged. [ABSTRACT FROM AUTHOR]

Chemical analyses were combined with a biological assay to investigate the main estrogenic chemicals as they passed through a sewage treatment works (STW) and entered a river. The STW studied was unusual in that it received wastewater from the textile trade. This wastewater was shown to contain high concentrations of alkylphenol polyethoxylates and their degradation products, such as nonylphenol. High-performance liquid chromatography fractionation, combined with biological assay, showed that the majority of the estrogenic activity was contributed by the alkylphenolic chemicals and the natural estrogens 17 β-estradiol and estrone. Despite removal of a high proportion of the alkylphenolic chemicals by the various treatment processes within the STW, concentrations in the final effluent were still high compared to most other STW effluents in the United Kingdom. The effluent was very estrogenic to caged fish, as was the river water 2 and 5 km downstream of the STW, even though less so. Using various approaches, attempts were made to determine which group of chemicals contributed most to the estrogenic activity of the effluent. The analysis suggested that, in this unusual situation, the alkylphenolic chemicals may contribute the majority of the estrogenic activity of the effluent. However, this conclusion was based on a number of uncertainties that are presently unresolved and hence can be considered only tentative. [ABSTRACT FROM AUTHOR]

Abstract Evidence from the field and laboratory has shown that reproduction and early life-stage survival of several species of teleost fishes have been adversely affected following the release of several classes of synthetic, organic chemicals into the environment. Field studies from many geographic areas over several decades have found associations between exposure to synthetic chemicals in the environment and effects on hatchability, embryological success and larval survival. In more recent research, exposure to sewage treatment and bleached kraft mill effluents has been correlated with changes in reproductive system development and alterations in the endocrine physiology of wild teleost fishes. Loss of fecundity and damage during various stages of development and reproduction have been associated with exposure to endocrine disruptors, including many currently used chemicals. The supporting laboratory studies have confirmed that various wild fish species are sensitive to certain synthetic chemicals at levels of exposure of parts per billion and parts per trillion, concentrations that are biochemically, physiologically, and environmentally relevant. This paper reviews the relevant field and laboratory research, and organizes the studies using the ecoepidemiological criteria of time-order, strength of association, specificity, consistency on replication, coherence and predictive performance. There is sufficient evidence to conclude that ambient concentrations of synthetic chemicals in some regions are at or above concentrations at which certain species could be affected. The viability of fishery resources must be linked not only to the quantity of habitat but also to the quality of habitat. [ABSTRACT FROM AUTHOR]

Frontal fibrosing alopecia (FFA) is a primary scarring alopecia with a variable prognosis.[1] We previously analysed the 12-month progression of the disease in a cohort of 106 patients treated with oral dutasteride 0.5 mg three times weekly and topical clobetasol and observed that the age of the patient, age at diagnosis of the disease and the clinical pattern (linear, diffuse or pseudo-fringe pattern) were prognostic factors of hairline regression, which ranges from 0.1 to 2.6 cm according to previous studies.[[2]] In order to increase the external validity of those results, we conducted a multicentric study that analysed severity of the disease, measured by hairline regression, and the risk factors of FFA previously described.[5] Hairline regression was categorized into five stages (I-V) as previously reported.[1] Table shows treatment modalities of the patients; the combination of topical treatment (clobetasol propionate, tacrolimus and minoxidil) and oral dutasteride 0.5 mg three times a week was the most used therapy (82.4%). In conclusion, FFA severity seems to be associated with the age of the patient, age of onset of the disease, duration of the disease, low academic level and body mass index. [Extracted from the article]

Alkylphenols (APs) dissolved in water are known to be toxic to animals including humans. In this study, regression models describing the toxicity of the 33 AP molecules were investigated for reproducing and thereby making it possible to predict a quantitative structure‐activity relationship (QSAR). For this purpose, we tried to derive regression models for the experimental IGC50 (growth inhibition concentration at 50 %) to Tetrahymena pyriformis by using various descriptor sets consisting of electronic and shape descriptors. By applying the multiple linear regression (MLR) analysis, it was successful to derive a quantitative regression model for the IGC50 values. In this analysis, the size parameters of the molecules were found important, suggesting that bulky molecules should be less toxic. We could also obtain, when the size descriptors were excluded, an MLR model indicating that the electron affinity (EA) should be important, which is consistent with the previous QSAR studies. Through the correlation analysis among the descriptors, it was shown that, in the present set of molecules, EA and a size parameter are highly correlated. Since EA was calculated to be negative, indicating that the related process would be energetically unfavourable, it was concluded that the size of the molecules should be a dominant factor determining IGC50. This implies that a molecular recognition process would play a critical role in the mode of action for the toxicity. [ABSTRACT FROM AUTHOR]

Studies were undertaken to assess sorption of seven endocrine-disrupting chemicals (EDCs), namely, estrone (E1), 17β-estradiol (E2), estriol (E3), 17α-ethynylestradiol (EE2), bisphenol A (BPA), 4-tert-octyl phenol (4-t-OP), and 4-n-nonyl phenol (4-n-NP) on four soils (from sandy to clay soil) with different physicochemical properties and biodegradation of five EDCs (BPA, E2, EE2, 4-t-OP, and 4-n-NP) in a loam soil associated with wastewater reuse. We also characterized the biotransformation of E2 to E1 in the loam soil under aerobic and anaerobic conditions. Sorption test using a batch equilibrium method demonstrated that alkylphenols (4-t-OP and 4-n-NP) had the strongest sorption onto soils, followed by estrogens (EE2, E2, E1, E3) and BPA. This laboratory study showed that all five EDCs, including the degradation product E1, were degraded rapidly in the soil within 7 d under aerobic conditions. However, under anaerobic conditions in the soil, little or no degradation of the five EDCs was noted except for E2, which showed slow degradation during the 70-d study. The calculated half-lives for E2 under anaerobic conditions were 24 d in the soil. Estradiol was found to be biotransformed to E1 under both aerobic and anaerobic conditions. The study suggested that the five EDCs as well as E1, which may be present in reclaimed wastewater, would not persist in well-aerated soil. But these EDCs persisting in anaerobic soil may affect soil and groundwater quality and ecosystem. [ABSTRACT FROM AUTHOR]

Water samples (n = 183) from Portuguese rivers were tested for the presence of endocrine disruptors using the recombinant yeast assay (RYA) combined with chemical identification of compounds having endocrine-disruption properties by liquid chromatography coupled to mass spectrometry. Ten selected locations were sampled monthly for a period of 20 months, from April 2001 to December 2002. More than 90% of samples showed either no detectable or low levels of estrogenicity (<0.1 ng/L of estradiol equivalents). The remaining samples (17 in total, 9.3%) showed estrogenicity values ranging from 0.1 to 1.7 ng/L of estradiol equivalents; only two samples showed values greater than 1 ng/L of estradiol equivalents. Most highly estrogenic samples (13 of 17 samples) originated in five sampling sites clustered in two zones near Porto and Lisbon. Chemical analysis detected alkylphenolic compounds (octyl- and nonylphenol plus nonylphenol ethoxylates) in all samples, albeit at concentrations less than 1 µg/L for each compound in 80% of samples. Total analyte concentration exceeded 10 µg/L in only 10 samples, with all but one of those originating from only two sampling sites. In these two locations, a good correlation was observed between the concentrations of octylphenol, nonylphenol, and to a lesser extent, bisphenol A in the samples and their estrogenicity values as calculated by RYA. We conclude that estrogenic activity can be explained by alkylphenol contamination in only these sites; for the remainder, we propose that pesticides and urban waste may be the main factors responsible for estrogenic contamination. [ABSTRACT FROM AUTHOR]