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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]

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.

In recent decades, increasing attention has been directed toward the effects of alkylphenols and bisphenols due to their demonstrated endocrine-disruptive effects. This study investigated the occurrence and potential risk assessment of two alkylphenols and seven bisphenols in surface water collected from rivers (Cau River, Duong River, and Thai Binh River) flowing through Bac Ninh province, one of the pivotal economic regions in the North of Vietnam. The results demonstrated that these compounds were widely distributed in the rivers. The average concentrations were ranked as follows: 4-tert-octylphenol (4-t-OP) (91.2 ng/L) > 4-nonylphenol (4-NP) (78.9 ng/L) > bisphenol S (BPS) (72.4 ng/L) > bisphenol A (BPA) (5.6 ng/L) > bisphenol F (BPF) (below method detection limit) with detection frequencies of 100% (except for BPF of 23%). The presence of alkylphenols and bisphenols in aquatic environments closely correlates with anthropogenic activity. The environmental risk assessment was carried out based on the Risk Quotient (RQ) evaluation, indicating that 4-NP poses medium risk in all three rivers. In addition, 4-t-OP, which is more toxic than 4-NP, poses high risk to aquatic organisms in the Duong River (RQ = 1.1), while BPA and BPS show low risk to aquatic organisms in three rivers (RQ < 0). [ABSTRACT FROM AUTHOR]

The oxidation of a series of alkylphenols (alkyl is methyl and/or isobornyl) with chlorine dioxide using the VO(acac)2 as the catalyst was studied. In the presence of VO(acac)2, the selectivity to quinones increases and the yield of oxidative chlorination products decreases significantly. [ABSTRACT FROM AUTHOR]

A high-performance liquid chromatography with diode array detector (HPLC-DAD) analytical method was developed for the simultaneous detection of 17 phenolic compounds, including phenols, chlorophenols, alkylphenols, and nitrophenols, in two types of water matrices: wastewater and surface water. Prior to HPLC-DAD determination, a solid-phase extraction (SPE) procedure was optimized. The proposed method uses multiwavelength analysis, with the optimum detection wavelengths selected as 268 nm, 280 nm, 386 nm, 304 nm, and 316 nm. The highest resolution was achieved using a chromatographic column, Eclipse XDB-C18 (150 × 4.6 mm, 5 μm), which was kept at 20 °C. The mobile phase consisted of a gradient elution program, with mobile phase A being a 0.1% H3PO4 aqueous solution and mobile phase B being acetonitrile. The flow rate was set at 0.6 mL/min. The 17 target phenolic compounds were fully separated in less than 27 min. All compounds showed good linear regression, with correlation coefficients higher than 0.999. The method's quantitation limits ranged from 4.38 to 89.7 ng/L for surface water and 7.83 to 167 ng/L for wastewater. The recovery rates were in the range of 86.2–95.1% for surface water and 79.1–86.3% for wastewater. The SPE-HPLC-DAD method was proven to be fast, sensitive, accurate, and reproducible. The developed method was successfully applied for the analysis of the 17 phenolic compounds in real surface water and wastewater samples, with phenol, 2,4-DNP, and 2,4-DNP being determined at levels greater than the method's limits of quantitation (LOQs). The proposed analytical method represents an original technical resource for the simultaneous determination of 17 phenolic compounds in environmental water matrices. [ABSTRACT FROM AUTHOR]

Alkylphenols (APs) may cause gestational diabetes mellitus (GDM) in pregnant women by impairing glucose metabolism through endocrine disruption. However, the current literature has limited epidemiological evidence on the association between APs exposure and the risk of GDM, especially the lack of evidence on joint exposure. Thus, we evaluated the effect of exposure to APs during early pregnancy on the risk of GDM. The study involved 2035 pregnant women from Guangxi Zhuang Birth Cohort (GZBC) in China. Poisson regression model, restricted cubic spline (RCS), Bayesian kernel machine regression (BKMR), and quantile g-computation (Qgcomp) were conducted to evaluate the effects of serum APs levels on the risk of GDM in pregnant women. For each Ln-unit increase in the serum nonylphenol (NP) of pregnant women, the adjusted relative risk (RR) for GDM risk was 1.12 (95 % CI: 1.00, 1.24). After sex stratification, the effect was more pronounced among pregnant women carrying female fetuses（RR=1.22; 95 % CI: 1.09, 1.38). The serum 4-t-octylphenol (4-T-OP) of the medium-exposure (adjusted RR = 3.25: 95 % CI: 1.30, 8.12) and high-exposure groups (adjusted RR = 2.90: 95 % CI: 1.15, 7.31) were related to a significantly increased risk of GDM in pregnant women carrying female fetuses only when compared to the low-exposure group. A reverse U-shaped nonlinear association was found between 4-n-octylphenol (4-N-OP) and 4-n-nonylphenol (4-N-NP) concentrations and GDM risk, and it was more susceptible in pregnant women carrying female fetuses. The Qgcomp and BKMR models showed that exposure to APs mixtures was correlated with an elevated risk of GDM in pregnant women carrying female fetuses (adjusted OR = 1.90: 95 % CI: 1.07, 3.38). Exposure to APs during early pregnancy may have potential fetal sex-specific effects on the risk of GDM, with pregnant women carrying female fetuses being more susceptible.

In this study, the spatial distribution of alkylphenols in the sediments of the Marmara Sea was investigated for the first time. The targeted alkylphenol analysis was made by gas chromatography with triple quadrupole (GC-MS/MS) system. The 4-tert-octylphenol and 4-nonylphenol were detected in the studied sediments, while 4-n-octylphenol was not quantified. The measured concentrations of 4-tert-octylphenol and 4-nonylphenol were in the range of

In this study, concentrations of alkylphenolic (AP) compounds were measured and quantified in sediments, soil and aerosols collected in the vicinity of Cortiou Creek in the coastal area of Marseilles directly downstream of wastewater treatment plants (WWTPs). The three isomers of the nonylphenols (NPs), i.e. NP1, NP2 and NP3, were detected in sediments throughout the plume with average concentrations at each station of 62.93 µg.kg−1, 28.09 µg.kg−1, and 117.58 µg.kg−1, respectively. The stations beyond the plume measured levels of 33.67 µg.kg−1, 11.11 µg.kg−1, and 23.89 µg.kg−1, respectively. These chemicals were also found principally in soil samples with average concentrations of each isomer distributed at 6 stations at amounts of 48.08 µg.kg−1, 19.49 µg.kg−1 and 339.13 µg.kg−1 exposed to the prevailing wind, while at stations protected from predominantly high winds, concentrations ranged from 5.8 µg.kg−1 to 41.41 µg.kg−1. The most wide-ranging measurement is for the occurrence of these APs in aerosol samples, which were detected at levels of 0.81 to 8.46 ng.m−1. In addition, 4 tert-OP and 4 n-OP were not detected in these samples. The most elevated isomers found in this study were NP1 (28.44%) and NP3 (57.54%) within the three different matrices. According to the predicted no-effect concentrations (PNECs), these concentrations in the sediments exceeded the PNEC value, which indicates that they are likely to exert an adverse effect on benthic organisms. Alkylphenols were found in three environmental matrices APs, which were detected in aerosol samples, ranged in concentration from 0.81 to 8.46 ng. m-2 The most elevated isomers found in this study were NP1 (28.44%) and NP3 (57.54%) APs were derived from the emission points of WWTPs and other sources Sedimentary APs exceeded the PNEC value, signifying a potentially adverse effect [ABSTRACT FROM AUTHOR]

A solid-phase microextraction (SPME) Arrow and high-performance liquid chromatography-UV detector (HPLC-UV, detection at 225 nm) based method was developed for the selective determination of nine alkylphenols (APs) in milk. The functionalized mesoporous UiO-66 (4-meso-UiO-66) was utilized as the new coating material, which was synthesized by post-modification of pore-expanded UiO-66-NH2 by an esterification reaction with 4-pentylbenzoic acid. It was fully characterized by X-ray photoelectron spectroscopy (XPS), fourier transformation infrared spectrometry, nitrogen sorption-desorption test, scanning electron microscopy, transmission electron microscopy, and X-ray diffractometer. The characterization results showed the ester groups and benzene rings were introduced into the 4-meso-UiO-66, and the mesoporous structure was predominant in the 4-meso-UiO-66. The extraction mechanism of 4-meso-UiO-66 to APs is the synergistic effect of Zr-O electrostatic interaction and the size exclusion effect resulting from XPS, selectivity test, and nitrogen sorption-desorption test. The electrospinning technique was utilized to fabricate the 4-meso-UiO-66 coated SPME Arrow and polyacrylonitrile (PAN) was used as the adhesive. The mass rate of 4-meso-UiO-66 to PAN and the electrospinning time were evaluated. The extraction and desorption parameters were also studied. The linear range of this method was 0.2–1000 μg L–1 with a coefficient of determination greater than 0.9989 under the optimal conditions. The detection limits were 0.05–1 μg L–1, the inter-day and intra-day precision (RSD) were 2.8–11.5%, and the recovery was 83.6%–112%. The reusability study showed that the extraction performance of this new SPME Arrow could be maintained after 80 adsorption-desorption cycles. This method showed excellent applicability for the selective determination of APs in milk. [ABSTRACT FROM AUTHOR]

Alkylphenols, which are industrial chemicals, are xenoestrogens; however, their sublethal effects on aquatic animals are poorly studied. The aim of this work is to study possible metabolic and reproductive disorders in amphipods using the example of Gmelinoides fasciatus from the Gulf of Finland (Baltic Sea) after experimental exposure to 4-tert-octylphenol (4t-OP) from the group of alkylphenols. The mortality of G. fasciatus amphipods in 4t-OP concentration ranges from 0.5 to 1000 μg/L after 96 h and 7 days increases with increasing concentration. At 4t-OP concentrations of 0.5 and 5 μg/L, the mortality of G. fasciatus has not been observed. At a concentration of 20 μg/L, after 7 days, the mortality of crustaceans is 20%; at a concentration of 100 μg/L, it is 60%. Exposure to sublethal concentrations of 4t-OP (0.5 μg/L) resulted in a decrease in sexual activity of these amphipods after 1 week: only 25% of amphipods retain precopulatory pairs versus 100% in control. Under chronic exposure (28 days) to the lowest concentration, males show signs of demasculinization (a decrease in the width of the gnatopods and an increase in the depth of the coxal plates); females show a decrease in the overall fecundity and irreversible disturbances in the state of embryos (a high proportion (>50%) of embryos stop their development at different stages of organogenesis). The study shows significant functional disorders of metabolic processes and reproduction in crustaceans even when exposed to nonlethal concentrations of octylphenol. These results confirm the high toxicity of this industrial pollutant, the presence of which in the aquatic environment can lead to irreversible changes in the biota. [ABSTRACT FROM AUTHOR]

The widely used 4-octylphenol (OP) belongs to the group of endocrine disrupters (ED). However, it exerts potentially adverse effects on human health and the environment and has been detected in various environmental matrices. Adsorption is an effective treatment method for removing ED. This study analyzes the adsorption process of OP on graphene oxide (GO) on a bench scale and the central composite design was used for analyses of adsorption with four factors, namely, adsorbate concentration (100 to 120 mg.L-1 COP), adsorbent concentration (0.2 to 3.4 g.L-1 CGO), contact time (15 to 90 min Ct), and pH (2 to 10). The results helped investigate adsorption capacity, adsorption kinetics pseudo-first order, pseudo-second order, Elovich equation, and in- traparticle diffusion (IPD) and equilibrium conditions Langmuir, Freundlich, and Redlich-Peterson by mathematical models and showed 158.92 mg.g-1 (120 mg.L-1 COP, 0.2 g.L-1 CGO, 90 min Ct, and pH 2) maximum adsorption capacity. Regarding kinetics, Elovich equation best fitted the experimental data (R² = 0.9961) and IPD indicated the adsorption process took place in the intraparticle and in the boundary layer. Redlich-Peterson model showed the best fit to the data (R² = 0.9971) in the isotherms. The study demonstrated the adsorption of OP by GO in an aqueous solution can be used over a wide range of pH and contact times with no significant loss of efficiency. [ABSTRACT FROM AUTHOR]

Phthalates (PAEs) and alkylphenols (APs), known as endocrine-disrupting compounds (EDCs), are ubiquitous in aquatic environments worldwide and may be harmful to aquatic ecosystems. This study is the first to comprehensively assess the occurrence and potential ecological risks of 12 EDCs in the surface sediments of seven major harbors in Taiwan. In addition, a correlation model was established between the concentration levels of individual PAEs and APs in the sediments and their production. The total PAEs concentrations in the sediments ranged between 129–1894 ng/g dw (mean: 558 ± 479 ng/g dw). Total APs concentrations ranged between<0.2–913 ng/g dw with a mean of 52 ± 178 ng/g dw. Among the 12 EDCs, bis(2-ethylhexyl) phthalate (55.1%) and diisononyl phthalate (31.6%) were the predominant PAEs, while 4-nonylphenol (93.2%) was the main AP. The occurrence and concentrations of PAEs and APs in the sediments were significantly correlated with their production (r = 0.989, p <.01), reflecting the status and degree of anthropogenic pollution. The concentrations of PAEs and APs in the sediments of Taiwanese harbors showed a potential decreasing trend over time, which should be related to strengthened regulations and changes in the industrial market. The estimated total risk quotient (TRQ) of algae exposed to the concentrations of 12 EDCs in sediments suggests moderate to high potential risks (TRQ = 0.74–2.18), while crustaceans (TRQ = 0.02–0.27) and fish (TRQ = 0.03–0.10) may have low to moderate potential risks. The main compounds responsible for these risks are dibutyl phthalate, dioctyl phthalate, and 4-nonylphenols. The results show that the pollution degree of surface sediments in the harbor could reflect anthropogenic pollution. Therefore, it is necessary to monitor the pollution of surface sediments in harbors, grasp the pollution situation, and evaluate the regulatory effect. [ABSTRACT FROM AUTHOR]

A competitive chemiluminescent immunoenzyme assay (CL-EIA) technique is proposed for the sensitive determination of one of the environmentally significant toxicants of anthropogenic origin-nonylphenol—in natural waters. The chosen chemiluminescent detection is characterized by a higher sensitivity compared to the colorimetric. The limit of nonylphenol detection was 9 ng/mL compared to 55 ng/mL for colorimetric one in optimal conditions. The developed analysis can be used for two purposes; it is highly sensitive for the possibility of toxicological analysis and dilution of complex matrices with raw buffer solution, as well as for the analysis of water samples without pretreatment and dilution. The method has a working range from 28 to 1800 ng/mL. The degree of nonylphenol revealing in the spiked samples of river, spring, and waterfall water was 82–119%. [ABSTRACT FROM AUTHOR]

Results are presented from gravimetric anti-corrosion studies of pyridine salts 1-(4-isohexylphenoxy-)-3-propylpyridinium bromide (I) and 1-(4-isohexylphenoxy-2-diethylaminostil-)-3-pyridinium bromide (II) on St. 3 steel in 0.5 N Н2SO4. The effect the temperature (298, 303, 313, 323, 333 K) and concentrations of compounds (0.025, 0.05, and 0.1 g/L) have on the rate of corrosion and protective effect is studied (duration of test, 3 h). It is established that compounds I and (especially) II are strong inhibitors: the degree of protection against corrosion for St.3 steel at concentrations of 0.1 g/L is 96% on average. The thermodynamic parameters of the process (ΔG, ΔH, and ΔS) are calculated, and the blocking mechanism for protecting the metal surface from corrosion is considered. [ABSTRACT FROM AUTHOR]

Alkylphenols are widely applied in the field of industry and agriculture, but their endocrine disrupting properties harm to human health. Moreover, alkylphenols often exhibit the low content in complex samples. Thus, we proposed magnetic covalent organic framework composites (Fe3O4@TatTpa) for efficient magnetic solid phase extraction (MSPE) of alkylphenols via hydrogen bonding, π-π and hydrophobic interactions. In combination with HPLC detection, good linearity (0.006–10 µg mL−1) with R2 (≥0.997) and low limit of detections (1.8–6 × 10−3 µg mL−1) were realized for alkylphenols. The proposed method was successfully employed to determine alkylphenols in soft drink, black oolong tea, and watermelon samples with satisfactory recoveries (86.1–118.5 %) and relative standard deviations (6.3–14.8 %).

Abstract Background While prenatal exposure to alkylphenols (APs) has been demonstrated to be associated with neurodevelopmental impairments in animals, the evidence from epidemiological studies remains limited and inconclusive. This study aimed to explore the link between AP exposure during pregnancy and the intelligence quotient (IQ) of preschool children. Methods A total of 221 mother-child pairs from the Guangxi Zhuang Birth Cohort were recruited. Nonylphenol (NP), 4-tert-octylphenol (4-T-OP), 4-n-nonylphenol (4-N-NP), and 4-n-octylphenol were measured in maternal serum in early pregnancy. Childhood IQ was evaluated by the Fourth Edition of Wechsler Preschool and Primary Scale of the Intelligence at 3 to 6 years of age. The impact of APs on childhood IQ were evaluated by generalized linear models (GLMs), restricted cubic spline (RCS), and Bayesian kernel machine regression (BKMR). Results In GLMs, prenatal exposure to NP and the second tertile of 4-T-OP exhibited an inverse association with full-scale IQ (FSIQ) (β = -2.38; 95% CI: -4.59, -0.16) and working memory index (WMI) (β = -5.24; 95% CI: -9.58, -0.89), respectively. Prenatal exposure to the third tertile of 4-N-NP showed a positive association with the fluid reasoning index (β = 4.95; 95% CI: 1.14, 8.77) in total children, as well as in girls when stratified by sex. A U-shaped relationship between maternal 4-T-OP and WMI was noted in total children and girls by RCS (all P nonlinear

Background: While prenatal exposure to alkylphenols (APs) has been demonstrated to be associated with neurodevelopmental impairments in animals, the evidence from epidemiological studies remains limited and inconclusive. This study aimed to explore the link between AP exposure during pregnancy and the intelligence quotient (IQ) of preschool children. Methods: A total of 221 mother-child pairs from the Guangxi Zhuang Birth Cohort were recruited. Nonylphenol (NP), 4-tert-octylphenol (4-T-OP), 4-n-nonylphenol (4-N-NP), and 4-n-octylphenol were measured in maternal serum in early pregnancy. Childhood IQ was evaluated by the Fourth Edition of Wechsler Preschool and Primary Scale of the Intelligence at 3 to 6 years of age. The impact of APs on childhood IQ were evaluated by generalized linear models (GLMs), restricted cubic spline (RCS), and Bayesian kernel machine regression (BKMR). Results: In GLMs, prenatal exposure to NP and the second tertile of 4-T-OP exhibited an inverse association with full-scale IQ (FSIQ) (β = -2.38; 95% CI: -4.59, -0.16) and working memory index (WMI) (β = -5.24; 95% CI: -9.58, -0.89), respectively. Prenatal exposure to the third tertile of 4-N-NP showed a positive association with the fluid reasoning index (β = 4.95; 95% CI: 1.14, 8.77) in total children, as well as in girls when stratified by sex. A U-shaped relationship between maternal 4-T-OP and WMI was noted in total children and girls by RCS (all P nonlinear < 0.05). The combined effect primarily driven by NP, of maternal AP mixtures at concentrations above the 50th percentile exhibited an inverse trend on FSIQ in total children and girls in BKMR. Conclusions: Prenatal exposure to various APs affects IQ in preschool children, and there may be nonmonotonic and sex-specific effects. Further investigation across the population is required to elucidate the potential neurotoxic effects of APs. [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]

Environmental pollution with plastics and plastic debris is one of the major issues in the world. In addition to the problem of microplastics formed from these wastes, additives leached from plastics are also an important aspect. This review paper pays particular attention to three phenolic compounds - bisphenol A (BPA), 4-n-nonylphenol, and 4-tert-octylphenol (4tOP) – used, among others, in the plastics industry. Numerous studies have shown that bisphenol A, 4-nonylphenol, and 4-tert-octylphenol are leached from plastic products, which is also an important source of their release into aquatic environments. The leaching process is influenced by external factors, including temperature, mixing, exposure to ultraviolet light, chemical or mechanical abrasion, and aging and brittleness of plastics. A significant amount of leaching tests are concerned on the migration of BPA from polycarbonate bottles into water. There is less comprehensive information on three phenolic compounds leached from different types of polymers. Moreover, despite the availability of several economic and ecological techniques for their removal from water and wastewater (including coagulation, adsorption, membrane processes, advanced oxidation), significant amounts are noted in some of the aquatic environments, which may cause harmful endocrine effects in organisms living in these ecosystems. [ABSTRACT FROM AUTHOR]

Humans are exposed to various bisphenols, alkylphenols and nitrophenols through dietary intake, food packaging and container materials, indoor and outdoor air/dust. This study aimed to evaluate exposure of Japanese pregnant women to environmental phenols by measuring target compounds in urine samples. From a cohort of the Japan Environment and Children’s Study, 4577 pregnant women were selected. Bisphenol A (BPA), bisphenol S (BPS), bisphenol F (BPF), bisphenol AF (BPAF), para-nitrophenol (PNP), 3-methyl-4-nitrophenol (PNMC), branched 4-nonylphenol (4-NP), linear 4-nonylphenol and 4-tert-octylphenol (4-t-OP) were analysed using a high-performance liquid chromatograph coupled to a triple-quadrupole mass spectrometer. The urinary metabolite data were combined with a questionnaire to examine the determinants of phenol exposure by machine learning. The estimated daily intake (EDI) and hazard quotient (HQ) of BPA were calculated. PNP (68.2%) and BPA (71.5%) had the highest detection frequencies, with median concentrations of 0.76 and 0.46 μg/g creatinine, respectively. PNMC, BPS, BPF and 4-NP were determined in 24.9%, 11.9%, 1.3% and 0.4% of samples, respectively, whereas BPAF (0.02%) and 4-t-OP (0.02%) were only determined in a few samples. The PNP concentrations measured in this study were comparable with those reported in previous studies, whereas the BPA concentrations were lower than those reported previously worldwide. The EDI of BPA was 0.014 μg/kg body weight/day. Compared with the tolerable daily intake set by the German Federal Institute for Risk Assessment, the median (95th percentile) HQ was 0.044 (0.2). This indicates that the observed levels of BPA exposure pose a negligible health risk to Japanese pregnant women. Determinants of bisphenol and nitrophenol exposure could not be identified by analysing the questionnaire solely, suggesting that biological measurement is necessary to assess exposure of pregnant women to bisphenols and nitrophenols. This is the first study to report environmental phenol exposure of Japanese pregnant women on a nationwide scale.

Parabens and alkylphenols pose serious hazards to human health, yet there are few studies on their exposure profiles and health risks in rural Chinese populations. In this study, 804 participants were selected from the Henan Rural Cohort in mid-eastern China. The plasma levels of parabens (methylparaben, ethylparaben, propylparaben, butylparaben (BuP)) and alkylphenols (4-tert-butylphenol (4-t-BP), 4-tert-octylphenol (4-t-OP)) were analyzed via liquid chromatography–tandem mass spectrometry. Linear regression models were used to investigate factors that may influence pollutant exposure levels. The correlation between contaminants was assessed using Spearman's correlation. The human contaminant intake was estimated using the estimated daily intake (EDI). The health risk was assessed using the hazard quotient (HQ). The detection frequency of four parabens and two alkylphenols exceeded 75%, with median concentrations of 0.444, 0.067, 0.078, 0.053, 8.810, and 6.401 ng/mL, respectively. Significant correlations were observed between parabens, as well as between 4-t-BP and 4-t-OP. Regarding gender, paraben concentrations were higher in women than in men, except for BuP. The EDI for pollutants except 4-t-OP was lower than their respective tolerable/acceptable daily intake. In total, 85.70% of participants had 4-t-OP HQ > 1. A widespread exposure to parabens and alkylphenols among the rural population was found. The high health risks of alkylphenol exposure indicate that alkylphenols should be used with caution. [ABSTRACT FROM AUTHOR]

The present systematic review addresses the influence of occupational exposures on prostate cancer risk. Eleven studies were analyzed for a range of occupational exposures, including but not limited to firefighting, physical activity, night shift work, chemical exposure, and solar ultraviolet radiation. The results of the review reveal that firefighters exposed to harmful substances, individuals engaged in physically strenuous work, and workers with chronic night shift routines showed an increased likelihood of developing prostate cancer. Moreover, the review identified an increased risk associated with exposure to certain chemicals, including alkylphenolic compounds and benzene-related substances. The evidence underscores the importance of considering the cumulative effect of multiple risk factors in a comprehensive risk assessment. However, the conclusions indicate the necessity for further research to deepen these relationships and develop more effective strategies for the prevention of prostate cancer. [ABSTRACT FROM AUTHOR]

Bisphenol A (BPA), an alkylphenolic compound, is one of the most polluting and hazardous organic chemicals. Its routine detection is, however, still rather expensive due to high-cost equipment. In this context, we applied the effect caused by BPA to the optical properties of surfactant-stabilized silver nanoparticles further modified with the use of ammonia (AgNP-NH3) to develop a simple and quantitative approach for BPA determination. The experimental conditions of the AgNP-NH3 probe were adjusted to establish a stable and sensitive response toward BPA in aqueous media. The use of probe dispersion measured at a wavelength of 403 nm enabled a limit of detection of 2.0 nmol L−1 (0.5 ng mL−1), with a linear response as a function of a concentration of BPA ranging from 10 to 120 nmol L−1 (from 2.2 to 27 ng mL−1). The use of vortex-assisted liquid–liquid microextraction ensured the application of selective determination to real tap and stream water samples, with recoveries ranging from 85.0 to 111%. The protocol developed herein is simple, sensitive, and selective, does not require the use of toxic labeling agents, and can be easily adapted for the routine analysis of BPA in different real samples. [ABSTRACT FROM AUTHOR]

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In this study, the spatial distribution characteristics of nine alkylphenols (APs) in the Yongding River and Beiyun River were analyzed. The differences in the concentrations and spatial distribution patterns of nine APs were systematically evaluated using principal component analysis (PCA). The relationships between the concentration distribution patterns and the risks associated with nine APs were investigated under various categories of land use conditions in the region. The results demonstrated that the APs were widely present in both rivers, and the pollution risks associated with the APs were more severe in the Yongding River than in the Beiyun River. The results show that the contamination risks associated with 4-NP were the most serious in the two rivers, with detection percentages of 100% and 96.3%, respectively. In the Yongding River, the APs showed a tendency of low concentration levels in the upper reaches and high levels in the middle and lower regions. Meanwhile, the overall concentration levels of the APs in the Beiyun River were relatively high. However, despite the differences between the upper and middle regions of the Yongding River, the distribution pattern of the APs in the Beiyun River was basically stable. The concentration levels and risk quotient of the APs were negatively correlated with the vegetation cover land use type and positively correlated with the cropland and unused land use types within 500 m, 1 km, and 2 km. The purpose of this study was to provide theoretical data support and a basis for AP pollution risk evaluations in the Yongding River and Beiyun River. [ABSTRACT FROM AUTHOR]

Textile is one of the biggest industries and it has an enormous impact on the global economy. However, the textile industry is labelled as the most polluting of all the industries and this is due to its contaminated wastewater. Textile wastewater contains organic hazardous compounds like alkylphenols (APs) such as nonylphenols (NPs), and alkylphenol ethoxylates (APEOs) for example nonylphenol ethoxylates (NPEOs), which may come from various detergents, wetting agents, emulsifying agents, etc. used in textile industries. Literature review revealed that no work was reported on the APs and APEOs in the textile wastewater of Bangladesh. This study reports the status of some APs and some APEOs after assessing wastewater of some textile industries in Dhaka, Bangladesh. Investigations were carried out with the wastewater of seven textile industries located in the Dhaka Division, Bangladesh. Tests were carried out by an Agilent Liquid Chromatography-Mass Spectrometer (LC-MS). The results revealed that none of the wastewater samples contained APs, and APEOs other than nonylphenol ethoxylates (NPEOs) a form of APEOs. And it might have released from the textile products treating stuff through dissolution process. Among all the seven industries, two industries (28%) contained nonylphenol ethoxylates (NPEOs). The mean concentrations of the detected NPEOs were determined as 11.27 ± 0.24 µg L-1 and 14.01 ± 0.09 µg L-1 in the wastewater of the mentioned two industries. The levels of the observed concentrations of NPEOs were much higher than the specified limits for textile wastewater. Findings of the present work will create pressure on the textile industries of home and abroad for treating textile wastewater effectively and not letting APEOs cum NPEOs in the wastewater. And such activities all over will pave the way to save the ecological system. [ABSTRACT FROM AUTHOR]

The sources and distribution characteristics of three phenolic endocrine-disrupting compounds (EDCs), e.g., alkylphenols (APs) (including nonylphenols (NPs) and 4-t-octylphenol (OP)) and Bisphenol A (BPA), were investigated in the rivers of the Pearl River Delta Region (PRDR) with complex land-use types. The mean concentrations of NPs, OP, and BPA in river water including wet and dry seasons were 87, 6, and 74 ng/L in the agricultural regions (n = 10), 135, 7, and 61 ng/L in the transitional regions (n = 8), and 249, 15, and 152 ng/L in the urban regions (n = 28). Contents of NPs and BPA were high in the river sediments (ranged from 7 to 3048 ng/g and 2 to 271 ng/g, respectively). Equilibrium analysis results suggested that sediment release was not the main source of the river EDCs. Principal component analysis (PCA) showed that sewage was the major source of EDCs in the dry season, while the leaching effect of rainfall on the agricultural soils, urban roads, and commercial products was an important source in the wet season. Furthermore, the ratio of APs and total concentration of phenolic EDCs (ΣEDCs) was used to characterize the agricultural regions and urban regions in the PRDR. The ratio was less than 0.6 in the agricultural regions while the ratio was large than 0.6 in the dry season and less than 0.6 in the wet season in urban regions. BPA and NPs in transitional region and urban region had small/medium potential risk to aquatic organisms. [ABSTRACT FROM AUTHOR]

The aim of this study from 2020 was to identify the role of rivers, including those with low water flow and a constant inflow of bisphenol A (BPA), 4-tert-octylphenol (4-t-OP) and 4-nonylphenol (4-NP) to the marine environment. Water samples were collected from the small rivers flowing into the Gulf of Gdańsk and from the Vistula River. Final assays were performed using high-performance liquid chromatography with a fluorescence detector (HPLC-FL). The highest concentrations of phenol derivatives were found in summer, most likely due to higher consumption of products containing phenol derivatives. Another factor may be the type of development in the catchment area. The measurements did not exceed the PNEC, though this does not mean that the amounts of phenol derivatives introduced into the Gulf of Gdańsk by rivers can be ignored. Mean loads of xenobiotics introduced to the sea via rivers have been calculated as over 320 kg y−1 of BPA and about 55 kg y−1 of 4-t-OP and 4-NP each. [ABSTRACT FROM AUTHOR]

The paper describes the pyrolytic transformation of hydrolysis lignin in 1,4-dioxane at a temperature of 250°C and a pressure of 13.0 MPa and the subsequent Ru/C-catalyzed hydrogenation of the products at a temperature of 250°C and a pressure of 10.0 MPa in an autoclave. It has been found that the thermal pyrolysis of hydrolysis lignin with 1,4-dioxane and the catalytic hydrogenation of pyrolysis products are accompanied by C−O and C−C bond cleavage and formation of a products mixture consisting of soluble oligomer and monomer phenol derivatives, products of their hydrogenolysis and hydrogenation, and also mixtures of C1−C5 gas hydrocarbons and C2−C5 alcohols, and ethers formed mainly during the destruction of the solvent (1,4-dioxane) under the reaction conditions. [ABSTRACT FROM AUTHOR]

The concentrations and human health risk associated with alkylphenols, bisphenols, Pb, Fe, Cd, and Cr were evaluated in samples of eight different canned foods sold in Lagos, Nigeria using standard techniques. The concentrations of Pb ranged from 0.002 to 2.84 mg/kg, Fe values ranged from 1.05 to 140.34 mg/kg, Cd levels ranged from 0.03 to 0.65 mg/kg, Cr levels ranged from 0.35 to 0.77 mg/kg, and bisphenol-A (BPA) values ranged from 33.90 to 70.14 ng/g across the canned foods. The estimated daily intake (EDI) through the consumption of the different canned foods sampled ranged from 3.67x10-6 to 2.33x10-2 mg/kg/day for Pb, 1.02x10-3 to 1.43 mg/kg/day for Fe, 1.50x10-5 to 6.61x10-3 mg/kg/day for Cd, 7.80x10-5 to 7.83x10-3 mg/kg/day for Cr, and 1.70x10-5 to 5.81x10-4 mg/kg/day for BPA. Most canned food groups had EDI values that were lower than the recommended provisional tolerable daily intake for the Joint Expert Committee on Food Additives However, canned peas and canned beans had EDI values that were higher than the recommended limits for Pb, Fe, and Cr. The results from the hazard index (HI) suggest that there is a risk of a non-carcinogenic toxic effect for canned tomatoes, canned fish, canned corn, canned beans, and canned peas as their values were greater than 1. Results from this study can be used to inform regulatory decisions, guide industry standards for the production of these products and used by consumers to make informed decisions about which canned foods to purchase and consume. [ABSTRACT FROM AUTHOR]

A competitive chemiluminescent immunoenzyme assay (CL-EIA) technique is proposed for the sensitive determination of one of the environmentally significant toxicants of anthropogenic origin-nonylphenol—in natural waters. The chosen chemiluminescent detection is characterized by a higher sensitivity compared to the colorimetric. The limit of nonylphenol detection was 9 ng/mL compared to 55 ng/mL for colorimetric one in optimal conditions. The developed analysis can be used for two purposes; it is highly sensitive for the possibility of toxicological analysis and dilution of complex matrices with raw buffer solution, as well as for the analysis of water samples without pretreatment and dilution. The method has a working range from 28 to 1800 ng/mL. The degree of nonylphenol revealing in the spiked samples of river, spring, and waterfall water was 82–119%.

The concentrations and human health risk associated with alkylphenols, bisphenols, Pb, Fe, Cd, and Cr were evaluated in samples of eight different canned foods sold in Lagos, Nigeria using standard techniques. The concentrations of Pb ranged from 0.002 to 2.84 mg/kg, Fe values ranged from 1.05 to 140.34 mg/kg, Cd levels ranged from 0.03 to 0.65 mg/kg, Cr levels ranged from 0.35 to 0.77 mg/kg, and bisphenol-A (BPA) values ranged from 33.90 to 70.14 ng/g across the canned foods. The estimated daily intake (EDI) through the consumption of the different canned foods sampled ranged from 3.67x10-6 to 2.33x10-2 mg/kg/day for Pb, 1.02x10-3 to 1.43 mg/kg/day for Fe, 1.50x10-5 to 6.61x10-3 mg/kg/day for Cd, 7.80x10-5 to 7.83x10-3 mg/kg/day for Cr, and 1.70x10-5 to 5.81x10-4 mg/kg/day for BPA. Most canned food groups had EDI values that were lower than the recommended provisional tolerable daily intake for the Joint Expert Committee on Food Additives However, canned peas and canned beans had EDI values that were higher than the recommended limits for Pb, Fe, and Cr. The results from the hazard index (HI) suggest that there is a risk of a non-carcinogenic toxic effect for canned tomatoes, canned fish, canned corn, canned beans, and canned peas as their values were greater than 1. Results from this study can be used to inform regulatory decisions, guide industry standards for the production of these products and used by consumers to make informed decisions about which canned foods to purchase and consume.

The depolymerization of enzymatic hydrolysis lignin (EHL) is examined over one-step hydrothermal-synthesized MoS 2 in ethanol without hydrogen gas. Value-added aromatic molecules, mainly including alkyl-substituted phenols (A-Ps), are obtained without char or tar formation. The MoS 2 samples prepared with different Mo and S precursors have been tested and the highest aromatic monomer yield of 226.4 mg/g EHL is achieved over the MoS 2 prepared with thioacetamide and sodium molybdate as precursors (STA-MoS 2) at 320 °C for 12 h. Proper ratios of Mo6+/Mo5+ (~0.46–0.65) and (Mo6++Mo5+)/Mo4+ (~0.47–0.62) on the surface of MoS 2 catalysts are found to be significant for the achievement of high overall aromatic monomer yield. MoO x S y species with Mo5+ and S 2 2- is proposed as the active site for the production of complex alkyl phenols via demethoxylation and alkylation. The carbon deposition and the exchanges of sulfur and oxygen atoms resulted from the oxidization are likely responsible for the deactivation of catalyst. [Display omitted] • A hydrothermal MoS 2 exhibits high activity for alkyl phenols (A-Ps) from lignin. • Mo and S precursors play key roles in enzymatic hydrolysis lignin ethanolysis. • Proper Mo6+/Mo5+ and (Mo6++Mo5+)/Mo4+ ratios are crucial for aromatics. • Mo5+ and S 2 2- on MoO x S y are active sites for complex A-Ps. [ABSTRACT FROM AUTHOR]

The oxidation of alkylphenols (2,6-dimethylphenol, 3,5-dimethylphenol, 2-iso-bornylphenol, 2-isobornyl-5-methylphenol, 2-isobornyl-6-methylphenol) with chlorine dioxide in water and dichloromethane was studied. The specific features of alkylphenol oxidation under different reaction conditions were revealed. The reaction of alkylated phenols with chlorine dioxide resulted in the formation of quinones and products of oxidative chlorination. The yields of quinones were found to depend on the position of substituents in the aromatic ring of the starting phenols. [ABSTRACT FROM AUTHOR]

Copyright of Food & Machinery is the property of Food & Machinery Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Alkylphenols can originate from numerous products containing alkylphenol ethoxylates, including cleaning products, household items, and cosmetics. Some phenols, such as nonylphenol, are known to be endocrine disruptors, and exposure to them is thought to have contributed to the recent increase in allergic diseases such as asthma. However, the impacts of prenatal phenol exposure on asthma development in children are still unclear. We analyzed the association between maternal urinary phenol concentrations during early pregnancy and the development of asthma in children at the age of 4, using data from the Japan Environment and Children's Study (JECS), a large-scale nationwide birth cohort study. We recruited 3,513 pairs of mothers and children participating in the Sub-Cohort Study of JECS. We measured 24 phenols, including nitrophenol, parabens, bisphenol, octylphenol, and nonylphenol, in urine samples taken during the first trimester of pregnancy. The urinary levels of these phenols differed markedly, and some showed a broad spectrum of distribution. Methylparaben was detected at high levels in almost every participant (267.7 ng/ml, standard deviation 433.78). Logistic regression analysis revealed that the odds ratio of asthma onset for high exposure to butylparaben was 1.54 (95% confidence interval: 1.11–2.15). Additionally, logistic regression analysis by gender revealed an asthma development odds ratio of 2.09 (95% confidence interval: 1.20–3.65) for males and 0.65 (95% confidence interval: 0.25–1.70) for females born to mothers in whom 4-nonylphenol was detected, suggesting a gender difference. Our current analysis using large cohort data suggests that high exposure to butylparaben and low exposure to 4-nonylphenol during pregnancy are risk factors for asthma development in children. These findings establish a valuable foundation for formulating recommendations about prenatal phenol exposure. [Display omitted] • 3,513 mother-child pairs were analyzed for the association between phenol and asthma. • Total of 24 phenols were measured in urine samples collected from pregnant mothers. • Children born to mothers with high butylparaben had a higher risk of asthma. • Male children born to mothers with 4-nonylphenol had a higher risk of asthma. [ABSTRACT FROM AUTHOR]

[Display omitted] • CO 2 assisted fast pyrolysis of palm kernel shells. • Ni-Ce/CN50 catalyst enhanced oxygen removal efficiency. • High potential use of NiCe/CN50 catalyst for phenol production. • The presence of Ce reduced coke formation. Catalytic fast pyrolysis is one of the most promising techniques for the production of bio-oils. Generally, pyrolysis is carried out in an inert atmosphere; however, reactive catalytic pyrolysis has emerged as an alternative technique for achieving high catalytic efficiency. Herein, NiCe/CN catalysts with different Ni:Ce ratios were developed, and their catalytic efficiency in the catalytic fast pyrolysis of palm kernel shells in a CO 2 atmosphere was evaluated. The effects of reaction conditions, including the reaction temperature (400–600 °C) and ratio of Ni:Ce (10:0, 10:1, 10:3, 10:5, and 10:10), on the product yields were studied using in situ and ex situ analyses. NiCe/CN50 exhibited enhanced oxygen removal efficiency owing to the presence of oxygen vacancies in CeO x. In addition, the acidic site of the catalyst promoted the highly selective demethoxylation of alkylphenols. The presence of Ce promoted the Boudouard reaction (C + CO 2 → 2CO), which reduced coke deposition on the spent catalyst. Our results indicate that the NiCe/CN50 catalyst exhibited good catalytic efficiency, achieving the highly selective production of alkylphenols and acetic acid and low deactivation. Therefore, NiCe/CN50 can be used as an alternative catalyst for phenol production from biomass via catalytic fast pyrolysis. [ABSTRACT FROM AUTHOR]

In this study, the effect of metal-loaded biochar as a catalyst on the catalytic pyrolysis of lignin was investigated. The metal active sites (Ni, Fe) were introduced into the pine sawdust-derived biochar by an incipient-wetness impregnation method, and then the prepared catalysts were tested in catalytic pyrolysis of lignin in a fixed-bed reactor. The results showed that the relative content of phenolic compounds increased to 79.69%–90.46% during the pyrolysis of lignin under the function of biochar-based catalysts. The biochar introduced with bimetallic Fe/Ni enhanced the dissociation of side chains of alkylphenols in the pyrolysis process. The selectivity to phenol increased from 14.52% to 49.02%, which simplified the composition of bio-oil. Bio-oil rich in hydrocarbons and phenols can be used as a substitute for petroleum fuel or as an industrial-grade chemical. Thus, low-cost and readily available Fe/Ni biochar-based catalysts provide an effective research basis for production of aromatic compounds in catalytic pyrolysis of biomass. • Fe/Ni-loaded biochar shows high performance on bio-oil upgrading. • Synergistic effect of Fe and Ni promoted dealkylation and deoxygenation. • High selectivity to phenol is achieved during the catalytic pyrolysis of lignin. [ABSTRACT FROM AUTHOR]

The liver toxicity of alkylphenols (APs) has been demonstrated in animal studies. However, relevant epidemiological evidence is still lacking in humans, especially during pregnancy. We obtained the levels of biochemical indicators of liver function in early (<13 weeks, mean gestation=9.80±1.96 weeks) and late (≥32 weeks, mean gestation = 37.23±2.45 weeks) pregnancies from 219 pregnant women in the Guangxi Zhuang birth cohort from 2015–2017. We also examined the serum levels of APs in these pregnant women in early pregnancy. The present study aimed to investigate the correlations between the exposure of pregnant women to APs and their serum liver function indices. The results of the generalized linear model (GLM) in this study revealed that nonylphenol (NP) was positively correlated with total bilirubin (TBIL) (P=0.04) in early pregnancy, and 4-n-nonylphenol (4-N-NP) was negatively correlated with glutamyl transferase (GGT) (P=0.012). In late pregnancy, NP was positively associated with TBIL (P=0.002), and 4-tert-octylphenol (4-T-OP) was positively correlated with alanine aminotransferase (ALT) (P=0.02). Restricted cubic spline (RCS) results revealed dose response relationships between NP and TBIL (Poverall=0.011) and between 4-N-NP and GGT (Poverall=0.007) in early pregnancy. In late pregnancy, there were dose response relationships between NP and TBIL (Poverall=0.001) and between 4-T-OP and ALT (Poverall=0.033). There was also a dose response relationship between NP volume and GGT with an inverted 'U' shape (Poverall=0.041, Pnonlinear=0.012). Bayesian kernel machine regression modeling (BKMR) revealed that TBIL increased significantly (P<0.05) with increasing levels of coexposure to APs in both early and late pregnancy. Overall, exposure to APs during pregnancy affects maternal liver function to varying degrees. The present study provides new epidemiological evidence that exposure to alkylphenols in pregnant women interferes with liver function. • The first study to link APs exposure during pregnancy to maternal liver function. • Different APs affect liver function variably during early and late pregnancy. • BKMR analysis shows significant TBIL increase with APs coexposure in pregnancy. [ABSTRACT FROM AUTHOR]

Parabens and alkylphenols pose serious hazards to human health, yet there are few studies on their exposure profiles and health risks in rural Chinese populations. In this study, 804 participants were selected from the Henan Rural Cohort in mid-eastern China. The plasma levels of parabens (methylparaben, ethylparaben, propylparaben, butylparaben (BuP)) and alkylphenols (4-tert-butylphenol (4-t-BP), 4-tert-octylphenol (4-t-OP)) were analyzed via liquid chromatography–tandem mass spectrometry. Linear regression models were used to investigate factors that may influence pollutant exposure levels. The correlation between contaminants was assessed using Spearman’s correlation. The human contaminant intake was estimated using the estimated daily intake (EDI). The health risk was assessed using the hazard quotient (HQ). The detection frequency of four parabens and two alkylphenols exceeded 75%, with median concentrations of 0.444, 0.067, 0.078, 0.053, 8.810, and 6.401 ng/mL, respectively. Significant correlations were observed between parabens, as well as between 4-t-BP and 4-t-OP. Regarding gender, paraben concentrations were higher in women than in men, except for BuP. The EDI for pollutants except 4-t-OP was lower than their respective tolerable/acceptable daily intake. In total, 85.70% of participants had 4-t-OP HQ > 1. A widespread exposure to parabens and alkylphenols among the rural population was found. The high health risks of alkylphenol exposure indicate that alkylphenols should be used with caution.

In this study, seven compounds of environmental and health concern were treated by electrooxidation to determine their removal efficiencies from domestic wastewater. A batch type lab-scale reactor was used for the treatment process, and the analytes studied included two obsolete pesticides, two alkylphenols, two hormones, and bisphenol A. Titanium oxide and graphite electrodes were used as anode and cathode, respectively. Parameters of the electrooxidation process including pH of wastewater, ionic strength, applied current and treatment period were optimized by the univariate approach to maximize the removal efficiency of the analytes from wastewater. The optimum conditions were determined as nonadjusted pH of wastewater, 1.5 A current, 15 min treatment period and 5.0 g/L sodium chloride. Dispersive liquid-liquid microextraction was used to preconcentrate analytes before and after treatment in order to calculate the removal efficiency of analytes. The removal efficiency obtained under the optimum conditions was satisfactory for all seven analytes at different influent concentrations. HIGHLIGHTS Seven endocrine disrupting compounds were removed from wastewater using electrooxidation.; Electrooxidation parameters were optimized univariately.; An optimized DLLME-GC-MS method was used to analyze influent and effluent samples.; Over 95% removal efficiency was recorded for all analytes spiked to wastewater at three different concentrations.;

Objective: An analytical method was established for determination of 13 kinds of bisphenols and alkylphenol compounds in liquid dairy products by salting-out-assisted liquid-liquid extraction coupled with HPLC-MS/MS. Methods: The salting-out-assisted liquid-liquid extraction pre-treatment method was adopted, and the detection was performed in the mode of negative ion source multiple reaction monitoring （MRM） by triple quadrupole mass spectrometry, and quantitative analysis was performed by matrix external standard method. Besides, the effect of extraction solvent type, selection and the usage of salting-out agents on the recoveries were studied and the performance of the method was evaluated. Results: The liquid dairy products were liquid-liquid extracted with acetonitrile as extraction solvent and 0.4 g sodium chloride as salting-out agents. The 13 kinds of phenols had a good linear relationship, and the correlation coefficients were all ＞ 0.99. The standard recovery rates of milk and yoghurt were 81.5% to 118.1% and 80.8% to 107.6%, respectively, and the relative standard deviations were 1.89% to 12.3% and 1.12% to 11.9%. The detection limits were 0.15 to 0.75 μg/kg, and the quantification limits were 0.5 to 2.5 μg/kg. One of the commercially available liquid dairy product was found to contain 4-NP, and the concentrations was 9.28 μg/kg. Conclusion: The established method is suitable for the rapid detection of 13 kinds of bisphenols and alkylphenol compounds in liquid dairy products.

Peroxidation of vegetable oils represents a major problem for the food and biodiesel industries, and it is greatly accelerated by oil degree of unsaturation and by temperature increase. Phenols represent the most common additives used to counteract oil peroxidation, however clear structure-activity relationships at high temperatures are not available. We report, herein, a kinetic study of O2 consumption during spontaneous peroxidation of sunflower oil at 130 °C in the presence of 18 antioxidants belonging to the main families of natural and synthetic phenols, including α-tocopherol, alkylphenols (BHT, BHA), hydroquinones (TBHD), catechols (quercetin, catechin) and gallates. Results show that TBHQ provide the best protection in terms of induction period (IP) duration and O2 consumption rate. EPR spectroscopy demonstrated that the inhibition activity is negatively correlated to the stability of the phenoxyl radical of the antioxidant (A•), suggesting that chain propagation with linoleate (RH) moieties A• + RH → AH + R• decreases the efficacy of those antioxidants forming persistent A• radicals. These results provide important information to optimize the antioxidant activity of phenols and of novel phenol-based materials. [ABSTRACT FROM AUTHOR]

The present work addresses the quantitative structure–antioxidant activity relationship in a series of 148 sulfur-containing alkylphenols, natural phenols, chromane, betulonic and betulinic acids, and 20-hydroxyecdysone using GUSAR2019 software. Statistically significant valid models were constructed to predict the parameter logk7, where k7 is the rate constant for the oxidation chain termination by the antioxidant molecule. These results can be used to search for new potentially effective antioxidants in virtual libraries and databases and adequately predict logk7 for test samples. A combination of MNA- and QNA-descriptors with three whole molecule descriptors (topological length, topological volume, and lipophilicity) was used to develop six statistically significant valid consensus QSPR models, which have a satisfactory accuracy in predicting logk7 for training and test set structures: R2TR > 0.6; Q2TR > 0.5; R2TS > 0.5. Our theoretical prediction of logk7 for antioxidants AO1 and AO2, based on consensus models agrees well with the experimental value of the measure in this paper. Thus, the descriptor calculation algorithms implemented in the GUSAR2019 software allowed us to model the kinetic parameters of the reactions underlying the liquid-phase oxidation of organic hydrocarbons. [ABSTRACT FROM AUTHOR]