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Mg-Al-layered double hydroxide (Mg-Al-LDH) modified nanoscale zero-valent iron (NZVI) (Fe@MgAl-LDH) was firstly synthesized and characterized by several techniques. The results showed that the layered double hydroxides were coated on the surface of nanoscale zero-valent iron particles. This new material exhibited good adsorption for bisphenol A, 4-octylphenol and 4-nonylphenol from water samples. Based on these, a sensitive method was developed for the extraction and preconcentration of bisphenol A, 4-octylphenol and 4-nonylphenol using magnetic Fe@MgAl-LDH nanoparticles as the solid phase extraction adsorbents prior to high performance liquid chromatography coupled with variable wavelength detection. Under the optimal conditions, linear responses were achieved in the range of 0.5–200 μg L −1 with the correlation coefficients (r) above 0.999. The detection limits of three analytes were in the range of 0.24–0.34 μg L −1 , and precisions were all below 2.5% (n = 6). The proposed method was evaluated with real water samples and the excellent spiked recoveries in the range of 96.0–99.3% were achieved. [ABSTRACT FROM AUTHOR]

In this work, a new electrochemical method has been developed using a cavity carbon-paste micro)electrode sensor (CP-CME) in cyclic voltammetry in order to detect alkylphenol micropollutants in water, especially 4-nonylphenol, 4-octylphenol and 4-tert-octylphenol. CP-CME sensor is characterized by small quantities of materials in the cavity and by a significant reduction of the electro-chemical interface in comparison to the usual carbon paste electrode. Especially with the CME, the ohmic drop and the double layer capacitance are notably reduced in cyclic voltammetry allowing measurements of alkylphenol concentrations in water without any electrolyte addition. First, the electrochemical sensor was used for the detection of alkylphenols in a classical cell. Anodic oxidation of alkylphenols appears as an irreversible electrochemical process and experiments at different scan rates demonstrate that alkylphenol oxidation at the CME is not limited by diffusion but by a limited quantity of electroactive species (adsorption of alkylphenols). Also a surface activation step is required prior to a new measurement so as to liberate the adsorption sites occupied by oxidized alkylphenols and to subsequently adsorb alkylphenols. The developed method was validated by examining the linearity ranges, the repeatability, the accuracy, as well as the detection limits for each alkylphenol which are very low and ranged between 20 and 35 nM. The established calibration curves cover a large concentration range allowing alkylphenols quantification. The calculated accuracy accounts to 92 % and 99 % for the different alkylphenols, indicating that the developed method shows a good repeatability and very high accuracy. Furthermore, the electrochemical sensor was used in a special flow cell and alkylphenols could be also detected continuously by the CP-CME in adapted conditions. Flow rate and adsorption time were optimized in order to obtain good and repeatable signals. In conclusion, the CP-CME sensor has demonstrated its capability to detect alkylphenols continuously and directly in water [ABSTRACT FROM AUTHOR]

Food detergents are commonly used in households. The main components of detergents include surfactants and water. It has been found that certain compounds, which may cause health concerns, appear in food detergents, such as alkylphenols, arsenic, and lead. After applying food detergents is when people may be exposed to various levels of these chemicals when there are residues. In this study, the Taguchi experimental design was performed to determine the possible factors that might affect the residual characteristics of food detergent on dishware, fruits, and vegetables. The results showed that the variety of detergent was found to be the most significant factor affecting the residue amounts of arsenic (62.9%) and lead (71.6%) on fruits and vegetables, whereas the concentration of detergent used affected the amount of lead residue only (10.5%). On the other hand, dishware material, the concentration of analytes, immersion time, and type of surfactant contributed to arsenic residues on dishware, whereas technical nonylphenol isomer residues on dishware increased as the concentration of spiked analyte increased. In addition, the occurrence of 1,4-dioxane, a possible human carcinogen, in household food detergents in Taiwan was also determined in this research by solid-phase microextraction and GC-MS. Among the 80 detergent samples, 71 contained different concentrations ranges of 1,4-dioxane, from 0.03 to ~3.73 µg/g. In the exposure assessment, it was estimated that the maximum amounts of 1,4-dioxane in contact with the skin from the use of household food detergent in Taiwan was 0.015 µg/kg/day. [ABSTRACT FROM AUTHOR]

Studies on the quality of marine environments in Italy have traditionally favoured heavily impacted areas, such as harbours and industrial areas, while there are few investigations aimed at the evaluation of the presence of organic pollutants in the areas of marine reserve. The aim of this study was to determine endocrine-disrupting compounds (EDCs) in the liver of white seabreams ( Diplodus sargus sargus ) from the Natural Reserve of Torre Guaceto, Italy. Among EDCs, alkyl-phenols 2,6-DTBP, 2,4-DTBP, OP, and BPA were identified and quantified. The mean concentration of 2,6-DTBP, 2,4-DTBP, OP, and BPA were 2.2, 2.0, 1.2 and 3.6 ng/g of liver, respectively, confirming the occurrence and transfer of these organic pollutants in the food web of marine organisms in marine reserves. [ABSTRACT FROM AUTHOR]

Selective oxidation of aliphatic C-H bonds in alkylphenols serves significant roles not only in generation of functionalized intermediates that can be used to synthesize diverse downstream chemical products, but also in biological degradation of these environmentally hazardous compounds. Chemo-, regio-, and stereoselectivity; controllability; and environmental impact represent the major challenges for chemical oxidation of alkylphenols. Here, we report the development of a unique chemomimetic biocatalytic system originated from the Gram-positive bacterium Corynebacterium glutamicum. The system consisting of CreHI (for installation of a phosphate directing/anchoring group), CreJEF/CreG/CreC (for oxidation of alkylphenols), and CreD (for directing/anchoring group offloading) is able to selectively oxidize the aliphatic C-H bonds of p- and m-alkylated phenols in a controllable manner. Moreover, the crystal structures of the central P450 biocatalyst CreJ in complex with two representative substrates provide significant structural insights into its substrate flexibility and reaction selectivity. [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]

The results of the study of removal of nonylphenol, octylphenol and their ethoxylates from real industrial and municipal wastewater are presented. Industrial wastewater was pre-treated by coagulation with FeCl3 and adsorption on zeolite, before discharging into municipal sewer system. Their removal efficiencies in primary sedimentation tank of municipal WWTP were very low. From the practical point of view, the highest and the most significant removal efficiencies within the whole WWTP were observed for nonylphenol and nonylphenol ethoxylates. Dominancy of abiotic mechanisms of alkylphenols removal follows from adsorption measurements. Activated sludge cultivated in lab-scale extended aeration tank accounted for relatively high adsorption affinity to these substances. Activated sludge sampled from municipal wastewater treatment plant (MWWTP) receiving industrial wastewater containing alkylphenols accounted for very low adsorption affinity to these pollutants. Significantly higher removal efficiency of octylphenol ethoxylates was observed with the O3/granular active carbon (GAC) process compared to the ozonation process alone. Lower toxicity impact of intermediates and products of ozonation treatment on Vibrio fischeri was measured in comparison to the O3/GAC process. Actually, the municipal WWTP effluent discharge concentration values complies with EQS values, including nonylphenols. [ABSTRACT FROM AUTHOR]

The objective of this study was to isolate a new bacterium and investigate its ability for degradation of various toxic organic compounds. Based on 16S rRNA gene sequence and phylogenetic analysis, the isolated strain was identified as Bacillus sp. CYR2. Degradation of various toxic compounds and growth of CYR2 strain were evaluated with 2 and 4% inoculum sizes. All the experiments were conducted for 6 days, flasks were incubated at 30oC under 180 rpm. Among the 2 and 4% inoculum sizes, bacteria showed highest growth and toxic compounds degradation at 4% inoculum size. Especially, compared to 2% inoculum size, growth of the strain CYR2 at 4% inoculum size was increased by 15.1 folds with 4-secondarybutylphenol, 9.1 folds with phenol, and 5.4 folds with 4-tertiary-butylphenol. Strain CYR2 at 4% inoculum size showed highest removal of phenol (84 ± 5%), followed by 4-tertiary-butylphenol (66 ± 3%), 4-secondary-butylphenol (63 ± 5%) and 4-nonylphenol (57 ± 6%). Compared with 2% inoculum size, degradation ability of strain CYR2 with 4% inoculum size was enhanced by 3.45 times with 4-tertiary-octylphenol, and 2.53 times with 4-tertiarybutylphenol. Our results indicated that the newly isolated Bacillus sp. CYR2 can be used for in situ bioremediation of phenol and alkylphenols contaminated water. [ABSTRACT FROM AUTHOR]

Phenol hydroxylases (PHs) play a primary role in the bacterial degradation of phenol and alkylphenols. They are divided into two main classes, single-component and multi-component PHs, having distinctive catalytic subunits designated as PheA1 and LmPH, respectively. The diversity of these enzymes is still largely unexplored. Here, both LmPH and pheA1 gene sequences were examined in activated sludge from oil refinery wastewaters. Phenol, p-cresol, or 3,4-dimethylphenol (3,4-DMP) supplied as extra carbon sources were rapidly mineralized by the microbial community. Analysis of LmPH genes revealed a wide range of sequences, most of which exhibited moderate similarity with homologs found in Proteobacteria. Moreover, the LmPH diversity profiles showed a dramatic shift upon sludge treatment with p-cresol or 3,4-DMP amendment. This resulted in an enrichment in sequences similar to LmPHs from Betaproteobacteria and Gammaproteobacteria. RT-PCR analysis of RNA extracted from wastewater sludge highlighted LmPH genes best expressed in situ. A PCR approach was implemented to analyze the pheA1 gene diversity in the same microbial community. Retrieved sequences fell into four clusters and appeared to be distantly related to pheA1 genes from Actinobacteria. Altogether, our results provide evidence that phenol degraders carrying LmPH are more diverse than PheA1 carrying bacteria and suggest that PHs with best adapted substrate specificity are recruited in response to (methyl)phenol availability. [ABSTRACT FROM AUTHOR]

The sources and levels of endocrine disrupting compounds in Kuwait's coastal areas were investigated. Phthalates, alkylphenols and estrogens were measured in the inflows and outflows of three sewage treatment plants as well as in the seawater and sediments from the sewage impacted coastal areas. Phthalate levels in the inflow of the treatment plants ranged from 8.9 to 78.3 μg/l; alkylphenols from 0.7 to 279 ng/l and estrogens from 30 to 368 ng/l. On average, the treatment plants removed about 80% of these compounds. The outflows, however, contained significant levels of all three classes of compounds. The seawater from the sewage impacted area also contained detectable levels of these compounds. Sediment samples from these locations contained elevated levels of phthalates (ranging from 2145 to 15,722 μg/kg) and lower levels of alkylphenols (ranging from 2.49 to 15.14 μg/kg) and estrogens (ranging from 4.1 to 214 μg/kg, dry wt.). [ABSTRACT FROM AUTHOR]

The presence of endocrine disrupting chemicals such as 4- n -octylphenol, 4- n -nonylphenol and bisphenol A in environmental samples and artificial products may cause health problems for human and organisms. This developed method was efficient for monitoring of those tracing emerging contaminates and the Plackett-Burman factorial design introduced in extraction step was timesaving. Matrix effect was also considered to ensure proper quantitation. Good linearity (r 2 > 0.99), low Method Detection Limits (MDL) and Method Quantitation Limits (MQL) range from 0.18 to 0.54 ng/g and 0.60 to 1.80 ng/g were obtained. Three level spiking experiment (4, 10, 15 ng/g) showed recoveries range from 74% to 113% for 4- n -octylphenol and 4- n -nonylphenol with RSD range from 2% to 11%. The method was finally applied to the analysis of real fish samples taken from Hunan Province, China, offering a reliable and effective means for monitoring of trace emerging contaminates in fishes largely consumed by residents. [ABSTRACT FROM AUTHOR]

The purpose of the study was to determine the concentration of bisphenol A (BPA), 4- tert-octylphenol (OP), and 4-nonylphenol (NP), in human hair, the fur of Baltic grey seals and the feathers of herring gulls. Hair was collected from 42 volunteers, while grey seal fur ( n = 17) came from the seal centre in Hel (Marine Station of Institute of Oceanography, University of Gdansk) and gull covert feathers ( n = 26) were collected from dead herring gulls along the Southern Baltic coast. Assays of phenol derivatives were conducted using the high performance liquid chromatography with fluorescence detection technique. In human hair, the mean BPA concentration amounted to 411.2 ng g dw, OP 131.2 ng g dw, NP 4478.4 ng g dw, in seal fur BPA 67.5 ng g dw, OP 62.8 ng g dw, NP 39.1 ng g dw, and in feathers BPA 145.1 ng g dw, OP 162.0 ng g dw, NP 37.7 ng g dw. The increase of the analysed EDCs in hair was significantly influenced by diet rich in products of marine origin, as well as hair colouring, heating up food in plastic containers, using home cleaning products without protective gloves and wearing newly purchased clothes without washing them first. The concentration of phenol derivatives in seal fur was influenced solely by the uniform diet rich in fish. In birds, the feeding area during molting significantly influenced the concentration of BPA, OP and NP found in covert feathers. [ABSTRACT FROM AUTHOR]

In the last decade, the impact of alkylphenols and bisphenol A in the aquatic environment has been widely evaluated because of their high use in industrial and household applications as well as their toxicological effects. These compounds are well-known endocrine disrupting compounds (EDCs) which can affect the hormonal system of humans and wildlife, even at low concentrations. Due to the fact that these pollutants enter into the environment through waters, and it is the most affected compartment, analytical methods which allow the determination of these compounds in aqueous samples at low levels are mandatory. In this review, an overview of the most significant advances in the analytical methodologies for the determination of alkylphenols and bisphenol A in waters is considered (from 2002 to the present). Sample handling and instrumental detection strategies are critically discussed, including analytical parameters related to quality assurance and quality control (QA/QC). Special attention is paid to miniaturized sample preparation methodologies and approaches proposed to reduce time- and reagents consumption according to Green Chemistry principles, which have increased in the last five years. Finally, relevant applications of these methods to the analysis of water samples are examined, being wastewater and surface water the most investigated. [ABSTRACT FROM AUTHOR]

Magnetic solid phase extraction (MSPE) with cobalt ferrite nanoparticles coated with oleic acid is described for the determination of alkylphenols (APs), 4-tert-butylphenol (TBP), 4-pentylphenol (PP), 4-hexylphenol (HP), 4-tert-octylphenol (TOP), 4-n-octylphenol (OP) and 4-nonylphenol (NP) in baby foods using gas chromatography with mass spectrometry (GC–MS). Prior to MSPE, the sample was treated with trichloroacetic acid, and the APs derivatized with acetic anhydride. Parameters affecting the extraction efficiency: amount of magnetic nanoparticles, extraction time and desorption conditions, were optimized. The enriched phase obtained was evaporated to dryness and the residue reconstituted in 50 μL of methanol, 1 μL of which was injected into the GC–MS. Samples were quantified applying matrix-matched calibration and using 2-chloro-5-bromoanisole as surrogate standard. The analysis of 0.5 g of sample provided detection limits in the 0.4–1.7 ng g −1 range. Some samples contained APs at levels of between 3 ng g −1 for HP and 122 ng g −1 for TOP. [ABSTRACT FROM AUTHOR]

Despite the presence of endocrine disrupting mercury, PAHs, alkylphenols and bisphenol A in inhaled air, scientific literature lacks information on their penetration into the lungs. Large lung capacity in birds makes this route of penetration more significant than in other animals. The studies were conducted on lungs of herring gulls found in the Gulf of Gdansk area. The results were juxtaposed with other tissues, including the intestines, which reflect the main, alimentary penetration route of harmful substances into the organism. It was determined that the capacity of bird's lungs, affects the efficiency with which mercury is absorbed from the air. Birds found to have high mercury concentrations in lungs had low PAHs concentrations, what was determined by the fact that the birds foraged in two different areas, as well as on different trophic levels. The alimentary route of phenol derivatives into the organism was of greater significance than inhalation. [ABSTRACT FROM AUTHOR]

Many man-made chemical compounds are recognized as endocrine disruptors and once released into the environment are likely to spread and bioaccumulate in wild species. Due to their lipophilic nature, these substances pass through the cell membrane or bind to specific receptors activating physiological responses that in the long run can cause reproductive impairment, physiological disorders, including the occurrence of metabolic syndromes. One significant source of contamination is represented by the consumption of polluted food. As a consequence, different environmental pollutants, with similar or different modes of action, can accumulate in organisms and biomagnify along the food web, finally targeting humans. The aim of this study was to analyze, under controlled conditions, the effects induced by the consumption of contaminated diets, focusing on the effects exerted at hepatic level. Juvenile seabream were fed for 21 days a diet enriched with different combinations of pollutants, nonylphenol (NP), tert -octylphenol ( t- OP) and bisphenol A (BPA). The different diets containing 5 mg/kg bw of each contaminant, were formulated as follows: NP + t OP, BPA + NP, BPA + t OP and NP + BPA + t OP (NBO). EDCs, at the doses administered, showed low biomagnification factor (BMF), suggesting that these pollutants hardly accumulate in muscles. The results obtained at hepatic level pinpointed the steatotic effect of all the administered diets, associated to a modulation of the expression of genes involved in lipid metabolism ( ppars, fas, lpl, and hsl ) . Results were compared to those obtained in previous studies in which fish were fed single pollutants evidencing that the administration of mixture of contaminants exerts a milder lipogenic effect, highlighting the contrasting/antagonistic interaction establishing among chemicals. Noteworthy was the setup of a new chromatographic method to detect the presence of the selected chemical in fish muscle and the application of Fourier Transform Infrared (FT-IR) analysis to evaluate pollutant-induced changes in the liver macromolecular building. [ABSTRACT FROM AUTHOR]

Five technical lignins (three organosolv, Kraft and soda lignin) were depolymerised to produce monomeric biobased aromatics, particularly alkylphenols, by a new two-stage thermochemical approach consisting of dedicated pyrolysis followed by catalytic hydrodeoxygenation (HDO) of the resulting pyrolysis oils. Pyrolysis yielded a mixture of guaiacols, catechols and, optionally, syringols in addition to alkylphenols. HDO with heterogeneous catalysts (Ru/C, CoMo/alumina, phosphided NiMO/C) effectively directed the product mixture towards alkylphenols by, among others, demethoxylation. Up to 15 wt% monomeric aromatics of which 11 wt% alkylphenols was obtained (on the lignin intake) with limited solid formation (<3 wt% on lignin oil intake). For comparison, solid Kraft lignin was also directly hydrotreated for simultaneous depolymerisation and deoxygenation resulting in two times more alkylphenols. However, the alkylphenols concentration in the product oil is higher for the two-stage approach. Future research should compare direct hydrotreatment and the two-stage approach in more detail by techno-economic assessments. [ABSTRACT FROM AUTHOR]

The sludge-derived carbon catalyst modified with 0 °C HNO 3 solution was tested in catalytic wet peroxide oxidation of m-cresol (100 mg L −1 ) with systematical mathematical models and theoretical calculation for the first time. The reaction conditions were optimized by response surface methodology (RSM) as T = 60 °C, initial pH = 3.0, C 0,H2O2(30%) = 1.20 g L −1 (lower than the stoichiometric amount of 1.80 g L −1 ) and C cat = 0.80 g L −1 , with 96% of m-cresol and 47% of TOC converted after 16 min and 120 min of reaction, respectively, and ξ (mg TOC/g H 2 O 2 fed) = 83.6 mg/g. The end time of the first kinetic period in m-cresol model was disclosed to be correlated with the fixed residue m-cresol concentration of about 33%. Furthermore, the kinetic constants in models of TOC and H 2 O 2 exactly provide convincing proof of three-dimensional response surfaces analysis by RSM, which showed the influence of the interaction between organics and H 2 O 2 on effective H 2 O 2 utilization. The reaction intermediates over time were identified by gas chromatography–mass spectrometer based on kinetics analysis. Four degradation pathways for m-cresol were proposed, of which the possibility and feasibility were well proven by frontier molecule orbital theory and atomic charge distribution via density functional theory method. [ABSTRACT FROM AUTHOR]

Two cultural artefacts produced in Southeast Asia were analysed by Py-GC–MS with in situ silylation using HMDS. The page of a Burmese book (Kammavaca manuscript) from the early 20 th century and a Cambodian wooden gilded sculpture representing a Buddha from the 16 th century were investigated for diagnostic purposes. Burmese lacquer (thitsi) and a drying oil were identified. Benzoic acid and alkylphenylketones were detected, indicating that oxidation at the benzylic position of thitsi monomers occurred. Alkylphenylketones resulted from the pyrolysis of the polymeric network, and we believe they were the result of the oxidising environment generated by the drying oil during the curing. In the case of the Cambodian Buddha, the detection of alkylphenylketones was crucial for identifying the lacquer, as the marker pyrolysis products of thitsi were present at the trace level. Alkylphenylcarboxylic acids, alkyl-oxo-phenylcarboxylic acids and alkylphenols with a carboxylic group on the side chain were also detected. These compounds were identified as trimethylsilyl derivatives on the basis of their mass spectra interpretation, and were present as free acids or esters. Although their molecular structure might be ascribed to the oxidation of the original components of thitsi, the length of the alkyl chains did not make the association straightforward. Therefore, we propose that the oxidative cleavage of the aromatic ring may be responsible for the formation of these compounds. [ABSTRACT FROM AUTHOR]

The composition of pyrolysis vapors obtained from alkali lignin pyrolysis with the additive of nickel formate was examined using the pyrolysis gas chromatography-mass spectrometry (Py-GC/MS). Characterization of bio-chars was performed using X-ray diffraction (XRD). Results showed that the nickel formate significantly increased liquid yield, simplified the types of alkali lignin pyrolysis products and increased individual component contents. The additive of nickel formate increased contents of alkylphenols and aromatics from alkali lignin pyrolysis. With an increase in temperature, a greater amount of the relative contents can be achieved. The nickel formate was thermally decomposed to form hydrogen, resulting in hydrodeoxygenation of alkali lignin during pyrolysis. It was also found that Ni is in favor of producing alkylphenols. The analysis based on the experimental result provided evidences used to propose reaction mechanism for pyrolysis of nickel formate-assisted alkali lignin. [ABSTRACT FROM AUTHOR]

It has been found that process time and temperature affect the isomer ratio of alkylphenols depending on the catalyst type. Phenol alkylation with linear α-olefins leads a prevalence of ortho-alkylphenols over the para-isomers, unlike the case of branched olefins. [ABSTRACT FROM AUTHOR]

Hydroxyl radical (OH) oxidation of toluene produces ring-retaining products: cresol and benzaldehyde, and ring-opening products: bicyclic intermediate compounds and epoxides. Here, first- and later-generation OH oxidation products from cresol and benzaldehyde are identified in laboratory chamber experiments. For benzaldehyde, first-generation ring-retaining products are identified, but later-generation products are not detected. For cresol, low-volatility (saturation mass concentration, C* ~ 3.5 x 104 - 7.7 x 10-3 μgm-3), first- and later-generation ring-retaining products are identified. Subsequent OH addition to the aromatic ring of o-cresol leads to compounds such as hydroxy, dihydroxy, and trihydroxy methyl benzoquinones and dihydroxy, trihydroxy, tetrahydroxy, and pentahydroxy toluenes. These products are detected in the gas phase by chemical ionization mass spectrometry (CIMS) and in the particle phase using offline direct analysis in real-time mass spectrometry (DART-MS). Our data suggest that the yield of trihydroxy toluene from dihydroxy toluene is substantial. While an exact yield cannot be reported as authentic standards are unavailable, we find that a yield for trihydroxy toluene from dihydroxy toluene of ~0.7 (equal to the reported yield of dihydroxy toluene from o-cresol (Olariu et al., 2002)) is consistent with experimental results for o-cresol oxidation under low-NO conditions. These results suggest that even though the cresol pathway accounts for only ~20% of the oxidation products of toluene, it is the source of a significant fraction (~20-40 %) of toluene secondary organic aerosol (SOA) due to the formation of low-volatility products. [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]

The west coast of Korea has experienced environmental deterioration for more than half a century. In the present study, we specifically aimed to: i) evaluate potential toxicities of contaminants in sediments that cause effects mediated through the aryl hydrocarbon receptor (AhR) and estrogen receptor (ER); ii) determine spatio-temporal distributions of polycyclic aromatic hydrocarbons (PAHs) and alkylphenols (APs); and iii) identify causes of greater potencies of samples. From 2010 to 2014, sediments were collected from 12 major estuarine and coastal regions along the west coast of South Korea. In vitro cell bioassays were performed to determine AhR- and ER-mediated potencies using H4IIE- luc and MVLN cells, respectively. Fifteen PAHs and six APs in sediments were identified by GC/MSD. Results of bioassays generally showed a low-to-moderate degree of contamination, however, greater AhR- and ER-mediated potencies were measured at some locations. Concentrations of PAHs and APs varied among locations, which indicated that sources were independently affected by the surrounding environment (e.g., industrial complex and cities). Results of bioassays were generally well correlated with concentrations of putative causative chemicals. Benzo[ k ]fluoranthene, dibenz[ a , h ]anthracene, and benzo[ b ]fluoranthene were the major AhR agonists, explaining approximately 30% of the bioassay-derived benzo[ a ]pyrene equivalent concentration (BaP-EQ). Unknown AhR and ER agonists and potential mixture effects remain in question. Overall, the present study provides baseline information on chemical contaminations and potential toxicity of sediments in a fairly wide geographical region of the west coast of South Korea. [ABSTRACT FROM AUTHOR]

The aim of the study was to investigate abiotic and biotic factors influencing the accumulation of endocrine disrupting compounds (EDCs) such as bisphenol A (BPA), 4- tert -octylphenol (OP) and 4-nonylphenol (NP) in mussels Mytilus trossulus from the Gulf of Gdansk (Southern Baltic). The key abiotic factor influencing BPA, OP and NP accumulation in mussels is their hydrophilicity/lipophilicity, which affects their main assimilation routes - by digestive tract for the more lipophilic OP and NP, and additionally by the gills for the less lipophilic BPA. As a result, high condition index (i.e. higher soft tissue weight) is more often correlated with high concentrations of OP and NP in mussels than with BPA. Furthermore, alkylphenols have 6–8 times greater accumulative potential than BPA. Concentration of the studied compounds was lower in females than in males following spawning, and the effect lasted longer for BPA than for alkylphenols. The influence of season and hydrological conditions on BPA, OP, NP in the mussel was more pronounced than the proximity of external sources of these compounds. An increase in water temperature in summer probably stimulated the solubility of BPA, the least lipophilic of the studied compounds, and led to increased assimilation of this compound from water (through gills). On the other hand, high OP and NP concentrations in mussels occurred in spring, which was caused by increased surface run-off and sediments resuspension. [ABSTRACT FROM AUTHOR]

Mesoporous polyaromatic frameworks (PAFs) based on tetraphenylmethane were obtained and modified with sulfonic acid groups. The compounds were characterized by solid-state C NMR and IR spectroscopy, low-temperature nitrogen adsorption-desorption, and transmission electron microscopy. The acidities of the PAF-1-SOH and PAF-2-SOH samples determined by titration were 3.99 mmol g and 0.91 mmol g, respectively. The catalytic activity of PAF-SOH for alkylation of phenol with linear terminal olefins was investigated. The reaction products were isomeric monoalkylphenols ( C-alkylates), and alkyl phenyl ethers ( O-alkylates). [ABSTRACT FROM AUTHOR]

The article reviews the dispersant use guidelines developed by the International Maritime Organization (IMO) guidelines focusing on the national dispersant authorization process and Net Environmental Benefit Analysis (NEBA). It mentions that dispersant use is one of the most discussed ways of dealing with marine oil spills; and chemicals had very high toxicity due to the presence of alkylphenol surfactants and aromatic hydrocarbons.

Phenols are significant environmental endocrine disruptors that can have adverse health effects on exposed individuals. Correlating phenol exposure to potential health implications requires the development of a comprehensive and sensitive analytical method capable of analyzing multiple phenols in a single sample preparation and analytical run. Currently, no such method is available for multiple classes of phenols due to electrospray ionization (ESI) limitations in concurrent ionization and lack of sensitivity to certain phenols, particularly alkylphenols. In this study, we investigated the influence of mobile phase compositions in ESI on concurrent ionization and analytical sensitivity of liquid chromatography–electrospray ionization–tandem mass spectrometry (LC–ESI–MS/MS) during the analysis of multiple classes of phenols, and we propose a comprehensive and sensitive analytical method for various classes of phenols (i.e., bisphenols, parabens, benzophenones, chlorophenols, and alkylphenols). The proposed method was affected by 0.5 mM ammonium fluoride under methanol conditions. It enabled the concurrent ionization of all the phenols and significantly improved the analytical sensitivity for bisphenols and alkylphenols, which typically have poor ionization efficiency. This method, combined with a "dilute and shoot" approach, allowed us to simultaneously quantify 38 phenols with good chromatographic behavior and sensitivity. Furthermore, the method was successfully applied to the analysis of 61 urine samples collected from aquatic (swimming) and land (indoor volleyball and outdoor football) athletes. • Fluoride-assisted LC–ESI–MS/MS method to determine multiclass phenols in urine. • Ammonium fluoride and methanol as a phenol-specialized mobile-phase composition. • Dramatic sensitivity enhancement of alkylphenols and bisphenols by fluoride ions. • Fast, simple and practical sample preparation without uncontrolled sample loss. • Successful application to 61 urine samples from athletes. [ABSTRACT FROM AUTHOR]

Alkylphenols ethoxylates are industrial surfactants, and the release in the environmental matrices produces degraded products, of which nonylphenol (NP) and octylphenol (OP) were the most common. They can be classified as endocrine disruptors since the estrogenic potential is widely recognized, but some others toxic aspects are in discussion. This study aimed to evaluate the toxicity of NP, OP, and mixtures of both through cellular, biochemical and genetic biomarkers in fish gonadal cell line RTG-2 exposed to nominal concentrations of 0.05; 0.5; 5; 50, and 100 μg mL−1 of each chemical and their mixtures of 0.05, 0.5; 5 μg mL−1 concentrations. After 24 h, the cells were collected for cytotoxic (neutral red – NR; crystal violet - CV, resazurin assay – RA and lactate-dehydrogenase - LDH), antioxidant system (glutathione- s -transferase – GST; superoxide-dismutase – SOD; glutathione-peroxidase – GPx and malondialdehyde – MDA) and genotoxic assays (alkaline comet assay and Fpg-modified alkaline comet assay). The chemicals and their mixtures were cytotoxic at 50 and 100 μg mL−1, in general aspect, but LDH showed cytotoxicity since 0.05 μg mL−1. The GST and SOD showed an activity increase trend in most tested groups, while GPx decreased at 5 μg mL−1 of the mixture. The MDA increase in all groups resulted in lipid peroxidation. The reactive oxygen species caused DNA damage for all groups. The tested chemicals and concentrations have been found in the freshwater systems. They can induce cell toxicity in several parameters that could impair the gonadal tissues considering the RTG-2 responses. [Display omitted] • LDH was the most sensible assay due to show loss of cell viability at low concentrations at the RTG-2 cell line. • The oxidative stress is the mediator of toxicity in all groups tested. • Oxidative DNA damage was observed at low concentrations to both chemicals and mixture. [ABSTRACT FROM AUTHOR]

Alkylphenols (APs) represent one of the highest exposure levels among endocrine disrupting chemicals (EDCs) in the South China Sea (SCS) due to their extensive use as plastic additives. The concerns about EDCs, including APs, have been reiterated since the surge in plastic waste from the COVID-19 response, but far less is known about the response of AP loadings in the SCS to emerging public policies and activities, including the COVID-19 pandemic. Here, we used cetaceans as bioindicators for monitoring two major APs, 4-nonylphenol (4-NP) and 4- tert -octylphenol (4-t-OP), in nine stranded cetacean species ( n = 110) in the SCS between 2004 and 2021. Prior to the COVID-19, APs loads showed decreasing temporal trends for finless porpoises and humpback dolphins, most likely due to China's restrictions on AP use or a shift in dominant prey species. Unexpectedly, AP loads continued to decline after the COVID-19 outbreak, probably due to a temporal-lag response of marine AP fluxes to the pandemic. The health risk assessments based on hormone biomarkers and toxicity thresholds suggest the potential adverse effects of APs on cetaceans, while recent declines in APs, though limited, may mitigate the detrimental impacts.

Endocrine disrupting compounds (EDCs) have been widely reported as potential carcinogenic threats to the human population. The release of EDCs to environmental compartments, such as water, sediment, and biota, has been monitored extensively. Considering the typically low levels of EDC concentrations found in environmental samples and the complexity of biota matrices, the main challenge is with the extraction and cleanup of samples, as well as with finding a sensitive enough instrumentation system for analyte detection. This paper presents a review of recent trends in the analysis of EDCs in environmental matrices. The focus of this review is three classes of environmentally important EDCs; namely, pharmaceuticals, estrogenic hormones, and alkylphenol compounds. Discussions about state-of-the-art instrumentation and sample preparation techniques, as well as a review of sample storage and preservation, are highlighted. Overall, the use of LC-MS-MS as an instrumentation technique has increased over the past 15 years. [ABSTRACT FROM AUTHOR]

During the past century, the amount of chemicals released into water bodies has increased, with particular emphasis being attributed to xenobiotics with endocrine disruption properties and/or pro-oxidant effects. Among these, it is possible to identify a specific chemical class, alkylphenols, which are of widespread use, and include a variety of chemicals with multiple uses. Bisphenol A is an important chemical used in industrial production of plastics, and has been extensively described as an endocrine disruptor. Paracetamol is a pharmaceutical compound used in human medicine, known for its therapeutic action but also for its evident pro-oxidant features. Additionally, previous studies have suggested that paracetamol may also exert endocrine disruption. The main goal of this study was to assess the effects of both paracetamol and bisphenol A as endocrine disruptors, and as promoters of oxidative stress and damage, on the freshwater microcrustacean Daphnia magna . The obtained results showed that bisphenol A was capable of altering population traits of exposed organisms, by impairing molting. On the contrary, paracetamol was not causative of any significant change in this parameter, despite having caused extensive oxidative stress. [ABSTRACT FROM AUTHOR]

The occurrence and distribution of nine selected compounds were investigated in surface water, suspended particulate matter (SPM), and sediment in Taihu Lake and its tributaries. With the exception of 4-Butylphenol, all compounds were detected in at least two phases, and nonylphenol (NP) and 4-tert-Octylphenol (4-OP) were the predominant alkylphenols (APs) in the lake. A significant correlation was observed between NP and 4-OP, indicating that they may share the same source. Moreover, surface water phase was the dominant sink of Bisphenol A (BPA) in the aquatic environment. The concentrations of BPA between the surface water and SPM phases were closely related to each other. In addition, Tetrabromobisphenol A (TBBPA) exhibited relatively higher concentrations and detection frequencies in the SPM. Risk assessment revealed greater risk associated with the surface water than the sediment, indicating that the discharge of industrial wastewater and domestic sewage poses a serious threat to aquatic ecosystems. [ABSTRACT FROM AUTHOR]

Previous studies using in vivo bioassay guided fractionation indicated that the herbicide diuron (3-(3,4-dichlorophenyl)-1,1-dimethylurea) and alkylphenol (AP)-containing surfactants were detected in fractions of extracts that induced the estrogenic biomarker, vitellogenin in fish exposed to surface water extracts from the United States. However, when the compounds were evaluated individually using in vivo estrogenic assays or in vitro estrogen receptor assays, estrogenic activity was not observed. Since APs have been shown to alter activity and content of cytochrome P450s (CYP) which convert diuron to potential estrogenic metabolites, the hepatic biotransformation of diuron was measured with and without a 7 day pretreatment of p -Octylphenol (OP) and p -Nonylphenol (NP) at low (OP 13 ng/L + NP 91 ng/L), and high concentrations (OP 65 ng/L + NP 455 ng/L) in juvenile male Nile tilapia ( Oreochromus niloticus ). Pre-treatment with the OP/NP (AP) mixture caused elevated levels of NADPH-catalyzed formation of 3,4-dichlorophenyl- N -methylurea (DCPMU) but not 3,4-dichlorophenylurea (DCPU). Fish were also treated with nominal concentrations of low (40 ng/L) and high (200 ng/L) diuron and each of its three degradates/metabolites: DCPMU, DCPU and 3,4-dichloroaniline (DCA). Additional treatments were conducted with APs and Diuron as a mixture at the low concentrations which mimicked concentrations observed in surface waters. Hepatic vitellogenin (Vtg) mRNA was induced by exposure to the high concentrations of Diuron, as well as DCPMU and DCPU in both concentrations. Brain cytochrome P450 aromatase activity was generally diminished by diuron, its metabolites, and the AP/diuron mixtures. 17β-Hydroxysteroid dehydrogenase (17βHSD) levels were also reduced by DCPMU and DCA in the lower concentrations, but not by higher concentrations. While the AP mixture reduced 17βHSD, the AP/diuron mixture induced testosterone (T) biosynthesis at the single concentration tested. Although CYP3A expression was induced by all diuron metabolites, it was unchanged by the AP mixture. These data indicate that mixtures of AP and diuron enhanced the formation of the metabolite (DCPMU) which induced vitellogenin, and reduced T biosynthetic enzymes (17βHSD inhibition). Overall, these data showed that APs may have induced the biotransformation of diuron to at least one metabolite, that may disrupt androgen biosynthesis and potentially alter steroid feedback pathways in the central nervous system. [ABSTRACT FROM AUTHOR]

Pain on propofol injection (POPI) is a minor problem that all anesthetists face every day. Introduction of several new formulations and hundreds of clinical trials have failed to find its remedy with just one intervention in all patients. This article highlights the causes of POPI and interventions that are used to eliminate this pain in current practice. Relevant articles from Medline and Embase databases were searched and included in this descriptive review with the following conclusions: (1) POPI is due to irritation of venous adventitia leading to release of mediators such as kininogen from kinin cascade. (2) When two or more drugs or measures are used, the incidence of POPI decreases considerably. Hence, the approach to eliminating POPI should be multimodal. (3) Any regimen that includes a drug having local anesthetic effect combined with central sedative/analgesic and rapid injection into a large vein should definitely reduce the risk of POPI to negligible levels. [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]

Stringent and periodic iteration of regulations related to the monitoring of chemical releases from the offshore oil and gas industry requires the use of ever changing, rapidly developing and technologically advancing techniques. Passive samplers play an important role in water column monitoring of produced water (PW) discharge to seawater under Norwegian regulation, where they are used to; i) measure aqueous concentrations of pollutants, ii) quantify the exposure of caged organisms and investigate PW dispersal, and iii) validate dispersal models. This article summarises current Norwegian water column monitoring practice and identifies research and methodological gaps for the use of passive samplers in monitoring. The main gaps are; i) the range of passive samplers used should be extended, ii) differences observed in absolute concentrations accumulated by passive samplers and organisms should be understood, and iii) the link between PW discharge concentrations and observed acute and sub-lethal ecotoxicological end points in organisms should be investigated. [ABSTRACT FROM AUTHOR]

Doxycycline can coordinate with europium (III) to form europium (III)-doxycycline complex, which can emit the fluorescence characteristic peak of europium (III) at 617 nm in alkaline solution, and the experiment proved that the fluorescence intensity could be further enhanced in the presence of silver nanoparticles and surfactant alkylphenols polyoxyethylene. So this method was applied to detect doxycycline content in duck meat in this research. First, 390 and 617 nm were selected as the optimum excitation wavelength and optimum emission wavelength by three-dimensional fluorescence spectrometry, respectively. Second, the experimental conditions were optimized through single factor experiment. Lastly, the samples of doxycycline concentration range of 0.05–12 mg/L were analyzed under the optimum experimental conditions. A good linear relationship between the doxycycline concentration and the fluorescence intensity was obtained, and the determination coefficient and the root mean squared error of prediction were 0.9982 and 0.4363 mg/L, respectively. This research showed that it was feasible to achieve the rapid detection of doxycycline content in duck meat by using silver nanoparticles and alkylphenols polyoxyethylene enhanced the fluorescence of europium complex. [ABSTRACT FROM AUTHOR]

Polystyrene suspensions with an average particle diameter of 0.1–0.25 μm and a narrow particle size distribution were synthesised in the presence of a mixture of surfactants – sodium alkyl sulphonate (E- 30), oxyethylated sulphated alkylphenol (AP-9), and organosilicon surfactant α,ω-bis[10-carboxydecyl] polydimethylsiloxane (CS). It was shown that the absence of a highly disperse particle fraction in the suspension is observed only when the polymerisation of styrene is carried out with an ionogenic surfactant content close to the critical micelle concentration (CMC). [ABSTRACT FROM AUTHOR]

A microwave-assisted extraction method for the determination of 15 alkyl, aryl, and halogenated phenols in sewage sludge and biosolids samples was developed and optimized. The effects of solvent, temperature, time, moisture content, acid, and number of extractions on the recovery of phenols were evaluated. Results indicated that extraction solvent had the greatest impact on the recovery of all phenols while pH had the largest effect on recovery of hexachlorophene and pentachlorophenol. Wet sludge samples were extracted with acetone-hexane mixture in the presence of glacial acetic acid. The extract was evaporated, acetylated by acetic anhydride and cleaned up by silica gel. For dry sludge samples, an optional procedure for the simultaneous extraction and acetylation of phenols was also proposed. Triclosan (TCS) and the alkyl and aryl phenols in sludge extracts were analyzed by gas chromatography-mass spectrometry (GC-MS) in electron-impact mode while polyhalogenated phenols were analyzed by GC-MS in negative ion chemical ionization mode. Method detection limits were ca. 200 ng/g for nonylphenol, <25 ng/g for TCS and other alkyl and aryl phenols, and <5 ng/g for other halogenated phenols. This method has been applied to the determination of phenolic compounds in over 150 sludge and biosolids samples since 2009. [ABSTRACT FROM AUTHOR]

A simple online headspace solid-phase microextraction (HS-SPME) coupled with the gas chromatography-mass spectrometry (GC-MS) method was developed for simultaneous determination of trace amounts of nine estrogenic odorant alkylphenols and chlorophenols and their derivatives in water samples. The extraction conditions of HS-SPME were optimized including fiber selection, extraction temperature, extraction time, and salt concentration. Results showed that divinylbenzene/Carboxen/polydimethylsiloxane (DVB/CAR/PDMS) fiber was the most appropriate one among the three selected commercial fibers, and the optimal extraction temperature, time, and salt concentration were 70 °C, 30 min, and 0.25 g/mL, respectively. The developed method was validated and showed good linearity ( R > 0.989), low limit of detection (LOD, 0.002-0.5 μg/L), and excellent recoveries (76-126 %) with low relative standard deviation (RSD, 0.7-12.9 %). The developed method was finally applied to two surface water samples and some of these target compounds were detected. All these detected compounds were below their odor thresholds, except for 2,4,6-TCAS and 2,4,6-TBAS wherein their concentrations were near their odor thresholds. However, in the two surface water samples, these detected compounds contributed to a certain amount of estrogenicity, which seemed to suggest that more attention should be paid to the issue of estrogenicity rather than to the odor problem. [ABSTRACT FROM AUTHOR]

Killer whales ( Orcinus orca ) have been deemed one of the most contaminated cetacean species in the world. However, concentrations and potential health implications of selected 'contaminants of emerging concern' (CECs) and new persistent organic pollutants (POPs) in endangered Southern Resident and threatened Bigg's (Transient) killer whales in the Northeastern Pacific (NEP) have not yet been documented. Here, we quantify CECs [alkylphenols (APs), triclosan, methyl triclosan, and per- and polyfluoroalkyl substances (PFAS)] and new POPs [hexabromocyclododecane (HBCCD), PFOS, PFOA, and PFHxS] in skeletal muscle and liver samples of these sentinel species and investigate in utero transfer of these contaminants. Samples were collected from necropsied individuals from 2006 to 2018 and analyzed by LC-MS/MS or HRBC/HRMS. AP and PFAS contaminants were the most prevalent compounds; 4-nonylphenol (4NP) was the predominant AP (median 40.84 ng/g ww), and interestingly, 7:3-fluorotelomer carboxylic acid (7:3 FTCA) was the primary PFAS (median 66.35 ng/g ww). Maternal transfer ratios indicated 4NP as the most transferred contaminant from the dam to the fetus, with maternal transfer rates as high as 95.1%. Although too few killer whales have been screened for CECs and new POPs to infer the magnitude of contamination impact, these results raise concerns regarding pathological implications and potential impacts on fetal development and production of a viable neonate. This study outlines CEC and new POP concentrations in killer whales of the NEP and provides scientifically derived evidence to support and inform regulation to mitigate pollutant sources and contamination of Southern Resident killer whale critical habitat and other marine ecosystems.

Many chemicals, including many endocrine disruptors (EDCs) are known to leach out from various plastic consumer products and waste, and are widespread in the environment. EDCs are a large group of contaminants that can interfere with hormonal metabolism or function. In addition, there are in the literature implications of contribution by EDCs in tumor progression, the last stage of carcinogenesis driven by cells with a metastatic phenotype. The process of epithelial cells losing their apical-basal polarity and cell-to-cell contacts, and acquiring migration and invasive properties typical of mesenchymal cells is called epithelial-mesenchymal transition (EMT). It is essential for tumor progression. In human cells, plastic-related EDCs, (phthalates, bisphenol A, and the alkylphenols: nonylphenol and octylphenol) reduce epithelial E-cadherin, and increase mesenchymal N-cadherin and extracellular matrix metalloproteinases. These changes are hallmarks of EMT. In xenograft mouse studies, EDCs increase migration of cells and metastatic growth in distant tissues. Their contribution to EMT and tumor progression, the topic of this review, is important from public health perspective, because of the ubiquitous exposure to these EDCs. In this mini-review we also discuss molecular mechanisms associated with EDC-induced EMT and tumor progression. [Display omitted] • Chemicals leaching out from plastics include endocrine disruptors. • The leaching endocrine disruptors can induce epithelial-mesenchymal transition (EMT). • EMT leads to cell migration and invasion essential in tumor progression and metastasis. • The leached endocrine disruptors probably contribute to tumor progression and metastasis. [ABSTRACT FROM AUTHOR]

Lignin can be converted into valued-added phenol-rich bio-oil by pyrolysis, but the melting and agglomeration nature causes serious problems for thermal conversion of lignin. To investigate the inner melting and agglomeration mechanism during lignin pyrolysis, three types of alkaline additives (monoacidic base NaOH, diacidic base Ca(OH) 2 and triacidic base Al(OH) 3) were employed in this study. Results showed that agglomeration behaviors during pyrolysis was determined by both of active functionalities and molecular structure in lignin. It was found that char foaming was partially reduced in L-3%Na, for the NaOH modification only inhibited active functionalities in lignin structure. For Ca(OH) 2 modification, the Ca(OH) 2 not only reacts with active functionalities in lignin but also links single lignin molecules to cross-linked macromolecule polymers, thus the agglomeration was completely eliminated in L-3%Ca. While, effects of Al(OH) 3 modification on agglomeration inhibition was negligible, due to its weak alkalinity. Analysis on bio-oil revealed that three alkali additives also promoted the mono-phenolics content in bio-oil. Specially, NaOH modification preferred to the formation of phenol, Ca(OH) 2 modification raised alkylphenols content, while the effect of Al(OH) 3 modification was the least. The maximum mono-phenols content (91.14%) and alkylphenols content (60.53%) was both obtained in L-10%Ca which pyrolyzed at 500 °C. • Agglomeration in lignin was decided by functionality and molecular structure both. • NaOH modification prefers to the formation of phenol in lignin bio-oil. • Ca(OH) 2 modification prefers to the formation of alkylphenols in lignin bio-oil. • Top mono-phenols of 91.14% and alkylphenols of 60.53% were obtained in L-10%Ca/500. [ABSTRACT FROM AUTHOR]

[Display omitted] • Origin and processing of thyme were traced by untargeted metabolomics. • Different phenolic profiles were evidenced as a result of the " terroir " effect. • Post-harvest sterilization led to distinctive phenolic profiling signatures. • PLS-DA and OPLS-DA multivariate statistics successfully discriminated samples. • Flavonoids and alkylphenols were prevalent among discriminant compounds. Thyme is one of Europe's most consumed aromatic herbs and represents a matrix susceptible to intentional mislabelling and food frauds. In this study, a phenolic profiling approach based on UHPLC-QTOF-HRMS untargeted metabolomics was used to trace its geographical origin, as well as to assess the effect of post-harvest processing by comparing sterilized vs non-sterilized thyme. Both unsupervised and supervised statistics led to reliable sample clustering, high-quality model parameters, as well as the identification of a total of 45 differential compounds (markers) for discrimination purposes. The phenolic signature was markedly affected by environmental conditions related to the region of production, leading to an overall higher abundance of flavonoids in Moroccan thyme (from Fez), flavanols in Polish one (from Lublin), and tyrosols and other phenolics in thyme cultivated in Spain (from Castilla-La Mancha). The processing was also shown to play an important role in phenolic profiling, noticing not only the decrease of thermolabile phenolics (such as flavonoids) but also the enhancement of other phenolic subfamilies in response to sterilization. This study opens the path to novel metabolomics-based strategies to support the integrity of thyme and possibly other spices, scarcely studied so far. [ABSTRACT FROM AUTHOR]