O-phenylphenol Research Articles

Rapid Determination of Seven Fungicides in Citrus Fruits

A rapid and simple determination method of seven fungicides, thiabendazole (TBZ), pyrimethanil (PYR), o-phenylphenol (OPP), fludioxonil (FLD), azoxystrobin (AZX), imazalil (IMZ) and diphenyl (DP) in citrus fruits by LC-MS and HPLC-FL was developed. The seven fungicides were extracted with acetonitrile from citrus fruits and cleaned up with Z-Sep/C18 cartridges. The LC separation was performed on a phenyl-hexyl column with methanol-acetonitrile-10 mmol/L ammonium formate (10 : 35 : 55) as a mobile phase. The recoveries from citrus fruits fortified with the compounds at the MRLs and at 0.1 μg/g ranged from 85.4 to 106.3% and from 75.8 to 99.7%, respectively. The quantitation limits (S/N=10) were 0.03-0.07 μg/g.

Higher urinary heavy metal, arsenic, and phthalate concentrations in people with high blood pressure: US NHANES, 2009–2010

Background: A link between environmental chemicals and human health has emerged but not complete in risk factors. This work aimed to study the relationships of different sets of urinary environmental chemical concentrations and risk of high blood pressure (BP) in a national, population-based study. Methods: Data was retrieved from United States National Health and Nutrition Examination Surveys, 2009–2010, including demographics, BP readings and urinary environmental chemical concentrations. Analyses included t-test and survey-weighted logistic regression models. Results: Urinary mercury concentrations were not associated with high BP (OR = 1.19, 95% CI 0.97–1.48, p = 0.095). Urinary cobalt (OR = 1.35, 95% CI 1.01–1.81, p = 0.044), lead (OR = 1.77, 95% CI 1.31–2.38, p = 0.001), antimony (OR = 1.37, 95% CI 1.09–1.72, p = 0.010) and tungsten (OR = 1.52, 95% CI 1.27–1.81, p < 0.001) concentrations were observed to increase the risk of high BP. There are no clear associations between environmental parabens and high BP. The effect of environmental bisphenol A (OR = 1.14, 95% CI 1.00–1.30, p = 0.051) disappeared after additionally adjusting for subsample weighting (OR = 1.12, 95% CI 0.93–1.35, p = 0.225). People with higher urinary mono-2-ethyl-5-carboxypentyl phthalate (OR = 1.26, 95% CI 1.00–1.58, p = 0.051), mono-n-butyl phthalate (OR = 1.19, 95% CI 1.01–1.41, p = 0.042) and mono-n-methyl phthalate metabolites (OR = 1.16, 95% CI 1.03–1.32, p = 0.021) tended to have high BP. Moreover, urinary o-phenyl phenol concentrations (OR = 1.49, 95% CI 1.25–1.77, p < 0.001) and dimethylarsonic acid concentrations (OR = 1.35, 95% CI 1.06–1.73, p = 0.019) were also seen to be associated with high BP. Conclusions: Urinary environmental chemical concentrations were associated with risk of high BP, although the causal effect cannot be established. Elimination of environmental chemicals in humans would need to be continued.

Rapid determination of six preservative residues in fruits and vegetables by high performance liquid chromatography using dispersive solid phase extraction

A dispersive solid phase extraction-high performance liquid chromatographic (HPLC) method was established for the simultaneous determination of 2,4-D, thiabendazole, 2-naphthol, o-phenyl phenol, diphenyl ether and biphenyl in the fruits and vegetables. The samples were vortexed for extraction with acetonitrile containing sodium chloride and anhydrous magnesium sulfate. The acetonitrile extraction was purified by acidic alumina dispersed solid phase extraction. The analysis was performed on an Agilent TC C18 column (250 mm x 4.6 mm, 5 microm) and an ultraviolet detector at 235 nm with a mobile phase of methanol-0.02 mol/L (pH 6) potassium dihydrogen phosphate solution, at a flow rate of 1.0 mL/min with gradient elution. Good linearities were observed in the range of 0.5-20 mg/L with correlation coefficients greater than 0.99. The average recoveries of the six preservatives in fruits and vegetables were in the range of 84.2% -99. 1% at three spiked levels of 1, 2 and 10 mg/kg (n = 6) and the relative standard deviations (RSDs) were in the range of 1.67%-10.3%. The limits of quantification were 1 mg/kg. This method is simple, accurate and suitable for the determination of the six preservatives in fruits and vegetables.

Study of Phenyl Phenol Formaldehyde Resin and its Curing Performance of Aniline

A new polymer amine modified phenyl phenol cresol resin preparing reports, physico-chemical constants and the ability to dissolve resin was determined, on the basis ofthe resin and the ring emulsion resin curing were studied.

Human urinary excretion of non-persistent environmental chemicals: an overview of Danish data collected between 2006 and 2012

Several non-persistent industrial chemicals have shown endocrine disrupting effects in animal studies and are suspected to be involved in human reproductive disorders. Among the non-persistent chemicals that have been discussed intensively during the past years are phthalates, bisphenol A (BPA), triclosan (TCS), and parabens because of their anti-androgenic and/or estrogenic effects. Phthalates are plasticizers used in numerous industrial products. Bisphenol A is the main component of polycarbonate plastics and epoxy resins. Parabens and TCS are antimicrobial preservatives and other phenols such as benzophenone-3 (BP-3) act as a UV-screener, while chlorophenols and phenyl phenols are used as pesticides and fungicides in agriculture. In spite of the widespread use of industrial chemicals, knowledge of exposure sources and human biomonitoring studies among different segments of the population is very limited. In Denmark, we have no survey programs for non-persistent environmental chemicals, unlike some countries such as the USA (NHANES) and Germany (GerES). However, we have analyzed the excretion of seven parabens, nine phenols, and the metabolites of eight different phthalates in urine samples collected over the past 6 years from four Danish cohorts. Here, we present biomonitoring data on more than 3600 Danish children, adolescents, young men, and pregnant women from the general population. Our study shows that nearly all Danes were exposed to the six most common phthalates, to BPA, TCS, and BP-3, and to at least two of the parabens. The exposure to other non-persistent chemicals was also widespread. Our data indicate decreasing excretion of two common phthalates (di-n-butyl phthalate and di-(2-ethylhexyl) phthalate) over time.

Rhizosphere and endophytic bacteria for induction of salt tolerance in gladiolus grown in sodic soils

Extensive development of canal irrigation system led to formation of unproductive sodic lands, which limited the cultivation of flower crop gladiolus in the basins of major rivers. The purpose of this study was to isolate native rhizospheric and endophytic bacteria from sodic environment and evaluate their growth enhancement and bio-ameloirant properties in gladiolus under sodic soils. Sixteen isolates of plant-growth-promoting rhizospheric and endophytic bacteria were isolated and screened for growth promotion potential. The promising strains were identified and evaluated for growth and production in gladiolus. The plants treated with strains CSR-G-1, CSR-B-2, and CSR-B-3 significantly produced marketable spikes and higher number of florets/spike. Also, the treated plants showed an increased activity of superoxide dismutase, phenyl alanine lyase, catalase, peroxidase, phenols, and proline than control. Further, the soil pH, total carbonates, and sodium adsorption ratio were lower in treated soils. The Na+/K+ ratio in leaves of treated plants was observed to be lower than control. In conclusion, these bio-inoculums can be used as growth enhancer and bio-ameliorant in sodic soils as an eco-friendly management strategy.

Comparisons between abiotic nitration and biotransformation reactions of phenolic micropollutants in activated sludge

The transformation of selected phenolic substances was investigated during biological wastewater treatment. A main emphasis was put on the relevance of abiotic processes leading to toxic nitrophenolic transformation products (TPs). Due to their environmental relevance, the antiseptic ortho-phenylphenol (OPP), the plastics additive bisphenol A (BPA) and the psychoactive drug dextrorphan have been studied. Batch experiments confirmed that nitro- and nitroso-phenolic TPs can be formed under acidic conditions when nitrite is present. HNO2, N2O3 and NO and NO2 radicals are likely involved in the abiotic process. It was found that the process was promoted by the freezing of water samples, since this can lead to an unexpected pH drop. However, under conditions present at wastewater treatment plants (neutral pH, low nitrite concentrations), the formation of appreciable concentrations is rather unlikely through this process, since HNO2 concentrations are extremely low and NO and NO2 radicals will also react with other wastewater constituents. Thus, the transformation of phenolic substances such as OPP and BPA is mainly caused by biotic transformation. In addition to hydroxylation as a common reaction under aerobic conditions, the formation of sulfate conjugates was detected with the original compounds as well as with nitrophenolic TPs. Therefore, even when nitro-phenolic substances are formed it is likely that they are further transformed to sulfate conjugates. In raw wastewater and WWTP effluent nitrated BPA and NO2-dextrorphan were not detected. Only nitro-OPP was found in the influent of a WWTP with 2.3 ng/L, but it was not identified in the WWTP effluents. The concentrations of dextrorphan increased slightly during WWTP passage, possibly due to the cleavage of the glucuronide-conjugate, its human metabolite form, or demethylation of the prodrug dextromethorphan.

Development of HPLC-MS/MS method for the simultaneous determination of environmental phenols in human urine

We present a sensitive method for simultaneous determination of bisphenol A (BPA), benzophenone-3 (BP-3), 4-tert-octylphenol (t-OP), ortho-phenylphenol (OPP), four parabens (methyl, ethyl, propyl, butyl parabens) and five chlorophenols (2,4-dichlorophenol (2,4-DCP), 2,5-dichlorophenol (2,5-DCP), 2,4,5-trichlorophenol (2,4,5-triclorophenol), 2,4,6-trichlorophenol (2,4,6-TCP), and triclosan (TCS)), in human urine by high-pressure liquid chromatography (HPLC) mass spectrometry (MS). Samples were processed using enzymatic deconjugation of glucuronides followed by solid phase extraction (SPE) on a C18 cartridge and the eluate was concentrated. Analytes were separated by reversed-phase HPLC and then detected by atmospheric pressure chemical ionisation (APCI) MS and quantified by isotope dilution method. We describe details for optimisation of each step of the procedure. The sample treatment steps are straightforward and not labour-intensive and, therefore, permit a high sample throughput with excellent prospects for automation. This method shows low inter-day variation, and detection limits for most of the compounds are below 1 ng/mL in 1 mL of urine. The method accuracy was also verified by the analysis of proficiency testing urine samples.

Bisphenol A and other phenols in urine from Danish children and adolescents analyzed by isotope diluted TurboFlow-LC–MS/MS

Bisphenol A (BPA), triclosan (TCS), benzophenone-3 (BP-3), dichoro- and phenyl phenols are industrial chemicals present in numerous consumer products such as polycarbonate plastics, preservatives in personal care products, sun screens, pesticides and fungicides, respectively, and they are all suspected endocrine disrupters. In this study the urinary excretion of eight phenols in Danish children recruited from the general population were investigated. One 24h urine and two consecutive first morning samples were collected from each of 129 healthy Danish children and adolescents (6-21 years). The concentrations of urinary phenols were analyzed by a new on-line TurboFlow-liquid chromatography-tandem mass spectrometry (LC-MS/MS) method. Most of the analyzed phenols were detectable in more than 80% of the 24h urine samples and the median concentration of BPA, TCS, BP-3, 2,4-dichorophenol and 2,5-dichorophenol (analyzed as ∑DCP), 2-phenylphenol and 4-phenylphenol were 1.37, 1.45, 1.41, 0.65, 0.36 and 0.53ng/mL, respectively. The ranges of the excreted TCS and BP-3 were wide; from below limit of detection to maximum levels of 955ng/mL and 162ng/mL, respectively, while the other phenols were excreted in a more narrow range with maximum levels below 25ng/mL. Concentrations in first morning urine were in general higher than in 24h urine and comprised 30-47% of the absolute amount excreted during 24h. The youngest children aged 6-10 years had a significantly higher urinary BPA concentration (ng/mL) and also a relatively higher daily BPA excretion (ng/kg bw/24h) than the older children and adolescents. The opposite pattern was observed for TCS, BP-3 and ∑DCP for which urinary levels increased significantly with age. No gender difference or associations to pubertal development were observed. In conclusion, our study showed that Danish children were exposed to multiple phenols simultaneously. Small children were relatively more exposed to BPA than older children, while higher exposures to TCS, BP-3 and ∑DCP were seen among adolescents.

Untargeted and targeted comprehensive two-dimensional GC analysis using a novel unified high-speed triple quadrupole mass spectrometer

The present manuscript is focused on the evaluation of a novel high-speed triple quadrupole mass spectrometer (QqQ MS), carried out under extreme GC conditions, namely those generated by a flow-modulated (FM) comprehensive two-dimensional GC (GC×GC) system. The novel QqQ MS system is capable of operation under high speed conditions, in both full-scan (maximum scan speed: 20,000amu/s) and multiple reaction monitoring (MRM) modes. Moreover, the QqQ MS instrument can generate simultaneous full scan/MRM data, also in a very rapid manner. An FM GC×GC–MSMS method was developed for the simultaneous full-scan qualitative analysis of untargeted essential oil compounds, and MRM quali/quantitative analysis of targeted ones, namely three preservatives [o-phenylphenol (OPP), butylated hydroxytoluene (BHT), butylated hydroxyanisole (BHA)]. The QqQMS system generated a sufficient number of data points per peak, for both qualitative and quantitative purposes. The degree of sensitivity, reached through the MRM analysis, widely exceeded current-day regulations. Method validation, related to the MRM analysis, was performed considering retention time, peak area and ion ratio repeatability, limits of detection and quantification, and accuracy. Additionally, a spearmint essential oil was spiked with 5 phytosanitary compounds at the 1ppb level, and analysed through an MRM-only GC×GC–MSMS application. Emphasis was devoted not only on sensitivity (satisfactory for all the contaminants), but also on the importance of precursor ion selection, and of the GC×GC separation process. Finally, sensitivity was compared between the MRM and SIM modes, in scan/MRM, MRM, scan/SIM and SIM analyses, performed on a mixture of 22 phytosanitary products, at a concentration level in the 50–150ppb range.

Re-evaluation of Developmental and Reproductive Toxicity of Ortho- Phenylphenol (OPP) and Sodium Ortho-Phenylphenate (SOPP)

Background: Due to widespread usage, the general public including pregnant women is routinely exposed to the fungicides, Ortho-Phenylphenol (OPP) and Sodium Ortho‑Phenylphenate (SOPP), from many sources. Previous data reviews concluded no effects on development or reproduction in animal studies but upon re-analysis we realize that alternative interpretation may exist. Methods: Developmental and reproductive effects were assessed from studies performed in rats, mice, and rabbits. We identified the most sensitive endpoint(s) for OPP or SOPP as they related to fetal developmental or reproductive toxicity. For quantifying the potential health risk associated with the exposure to OPP or SOPP, we used the lowest dose that caused no developmental or reproductive toxicity or benchmark dose analysis. Results: Developmental effects in OPP-treated rats and mice were decreased fetal body weight, increased incidences in delayed skeletal ossification and post‑implantation loss. In addition, fetal mice exposed to SOPP exhibited malformation. Similar to rats and mice, post‑implantation loss was the developmental effect noted in OPPtreated rabbits. Except for the rats, maternal toxicity appeared to be minimal (mice) or not observed (rabbits) at the lowest dose where developmental effects occurred (mice: cleft plate; rabbits: resorptions). We did not find evidence of OPP affecting reproductive functions but significant deviations from FIFRA Guidelines in these studies may prevent adequate assessment of the reproductive toxicity especially the effects on fertility and mating. Conclusions: The revised data analysis suggests that OPP and SOPP induce fetal toxicity in the absence of maternal effects. Our re-evaluation would be useful in the formulation of a current or updated regulatory strategy for the developmental toxicity of OPP and SOPP.

The protective effects of hydroxytyrosol against ortho-phenylphenol-induced DNA damage in HepG2 cells

Ortho-phenylphenol (OPP) has been found to cause carcinomas in the urinary tract of rats. Since OPP is a potent genotoxic compound, and used as fungicides and antibacterial agents in fruits and fruit products, search for newer, better agents for protection against toxicity of OPP is required. In this study, the chemoprotective effect of hydroxytyrosol (HT) against OPP-induced DNA damage in HepG2 cells was investigated. Comet assay was used to detect the DNA damage induced by OPP. To elucidate the possible mechanisms, we tested lysosomal membrane stability, mitochondrial membrane potential, intracellular generation of reactive oxygen species (ROS), and reduced glutathione (GSH). Results showed that HT significantly reduced the DNA strand breaks caused by OPP. Moreover, HT effectively suppressed OPP-induced ROS formation, and increased the GSH level. Lysosomal membrane and mitochondrial membrane were also protected when cells were pretreated with HT. These results suggested that the disruption of lysosomal membrane integrity and the oxidative stress, leading to DNA fragmentation, may be the mechanism of DNA damage induced by OPP. The antioxidant activity of HT may play an important part in attenuating the DNA damage of OPP.

Determination of Phenols and Phenates in Disinfectant Formulations by Liquid Chromatography with UV Detection: Collaborative Study

Fourteen collaborating laboratories assayed o-phenylphenol (OPP), p-t-amylphenol (PTAP), and o-benzyl-p-chlorophenol (OBPCP) in formulated products, both ready-to-use and concentrates, by RP-HPLC. The actives in the samples ranged from 0.03 to 11% OPP, 0.06 to 4% PTAP, and 0.07 to 10% OBPCP either in free forms or as salts. Seven blind duplicates were analyzed. The samples were diluted/extracted with acidified methanol, filtered, and analyzed by LC on a C18 column using gradient elution and UV detection at 285 nm. The concentration of the active ingredients was calculated from a standard curve. Each laboratory weighed each test sample twice within a single analytical run. The data were analyzed using all 14 laboratory results, with appropriate statistical tests to detect outliers. The repeatability RSDs ranged from 0.98 to 3.40% for the free phenols, and 1.26 to 2.51% for the salts. The reproducibility RSDs ranged from 5.31 to 7.80% for the free phenols, and 5.50 to 8.67% for the salts. The HorRat ranged from 0.86 to 2.17 for the free phenols, and 1.54 to 2.72 for the salts.

Sodium dodecyl sulfate sensitized electrochemical method for subnanomole level determination of ortho-phenylphenol at a novel disposable electrode

The electrochemical behavior of ortho-phenylphenol (OPP) at a disposable electrode (an improved wax-impregnated graphite electrode) in the presence of sodium dodecyl sulfate (SDS) was studied for the first time. The results demonstrated that the electrocatalytic oxidation process of OPP was accompanied with two-charge-two-proton transference. The electronic transmission coefficient (α) and diffusion coefficient (DR) for OPP were calculated to be 0.8126 and 3.61 × 10−2 cm2/s, respectively. The electrochemical signal was apparently improved by SDS at the disposable electrode and the oxidative peaks current was proportional to the concentration of OPP over the range from 1.0 × 10−9 to 4.0 × 10−6 mol/L with the detection limit of 8.7 × 10−10 mol/L. This novel and highly sensitive method can be successfully applied to detect OPP in the orange rind sample.

Sorption ofortho-Phenylphenol to Soils

Conflicting sorption coefficients for ortho-phenylphenol (OPP) have been reported in the literatures, which resulted in the conflicting assessments on OPP mobility in soil. To ascertain the sorption coefficient of OPP, batch experiments were performed based on OECD guideline 106, using three types of soils. Headspace solid-phase microextraction (HS-SPME) and GC-MS were applied to the determination of OPP concentration in the liquid phase. The sorption isotherms obtained for all three soils under equilibrium conditions were described well, assuming linear sorption. The organic carbon normalized distribution coefficients (Koc) ranged from 894 to 1703 L kg−1, which suggested that OPP is moderately mobile in soil. The results also showed that the Koc value of OPP can be predicted precisely from Kow, whereas it was underestimated by one order of magnitude when water solubility is used.

Sulfonation of anisole, phenol, toluene and related alkyl and alkoxy derivatives with SO3. The influence of the solvent system on the reactivity and the sulfonic acid product distribution

The reactions of anisole (1), phenol (2), the alkoxy- and alkylphenyl ethers 3–11, toluene (12) and the o-dialkylbenzenes 13–15 with sulfur trioxide in dichloromethane or trichlorofluoromethane have been studied. Our results have been compared with those obtained with the same substrates upon reaction with SO3 in nitromethane and dioxane. We show that ortho substitution is enhanced for sterically unhindered phenyl ethers and phenols due to complex formation between SO3 and the C(sp2)-bonded oxygen when dichloromethane is used as solvent instead of nitromethane or dioxane. This is mainly as a result of intramolecular SO3, transfer from the oxygen to the ortho carbon and subsequent conversion of the resulting σ-complex into the ortho sulfonic acid.

Potential for bioremediation of agro-industrial effluents with high loads of pesticides by selected fungi

Wastewaters from the fruit packaging industry contain a high pesticide load and require treatment before their environmental discharge. We provide first evidence for the potential bioremediation of these wastewaters. Three white rot fungi (WRF) (Phanerochaete chrysosporium, Trametes versicolor, Pleurotus ostreatus) and an Aspergillus niger strain were tested in straw extract medium (StEM) and soil extract medium (SEM) for degrading the pesticides thiabendazole (TBZ), imazalil (IMZ), thiophanate methyl (TM), ortho-phenylphenol (OPP), diphenylamine (DPA) and chlorpyrifos (CHL). Peroxidase (LiP, MnP) and laccase (Lac) activity was also determined to investigate their involvement in pesticide degradation. T. versicolor and P. ostreatus were the most efficient degraders and degraded all pesticides (10 mg l⁻¹) except TBZ, with maximum efficiency in StEM. The phenolic pesticides OPP and DPA were rapidly degraded by these two fungi with a concurrent increase in MnP and Lac activity. In contrast, these enzymes were not associated with the degradation of CHL, IMZ and TM implying the involvement of other enzymes. T. versicolor degraded spillage-level pesticide concentrations (50 mg l⁻¹) either fully (DPA, OPP) or partially (TBZ, IMZ). The fungus was also able to rapidly degrade a mixture of TM/DPA (50 mg l⁻¹), whereas it failed to degrade IMZ and TBZ when supplied in a mixture with OPP. Overall, T. versicolor and P. ostreatus showed great potential for the bioremediation of wastewaters from the fruit packaging industry. However, degradation of TBZ should be also achieved before further scaling up.

Single-Laboratory Validation of a Method for the Determination of Phenols and Phenates in Disinfectant Formulations by Liquid Chromatography with UV Detection

A single-laboratory validation study was conducted for an LC method using UV detection for the simultaneous determination of the active ingredients o-phenylphenol (OPP), p-tert-amylphenol (PTAP), and o-benzyl-p-chlorophenol (OBPCP) in disinfectant formulations. Samples were extracted, the extracts diluted with acidified methanol, and the active ingredients separated by LC with a gradient mobile phase and quantified by using UV detection at 285 nm. For each active ingredient, the RSD was < or = 3.7%, and the intermediate reproducibility was < or = 3.4%. The active ingredient content of the spiked samples analyzed in this study ranged from 0.075 to 10.1% for the individual phenol active ingredients. The average recovery ranges were 86.7-104.9, 82.8-115.6, and 91.6-114.7% for the active ingredients OPP, PTAP, and OBPCP, respectively, for the concentration range of 0.075-10.1%. This method, with a relatively short chromatographic run time (about 15 min), proved to be reliable and convenient for analyses of products or samples containing all or a combination of these phenol active ingredients.

The Orthophenylphenol (OPP) Residues in Some Citrus Fruits on the Market

The Orthophenylphenol (OPP) Residues in Some Citrus Fruits on the Market

Effect of iron and humic acid on photodegradation of some pesticides adsorbed on clay surfaces

Photochemistry studies can be helpful in assessing the environmental fate of chemicals. For this reason, the photodegradation kinetic studies of the two pesticides orthophenylphenol (OPP) and monuron, largely used in agriculture, were carried out in solid phase. The fungicide OPP and the herbicide monuron were irradiated on the clay fractions (montmorillonite and modified clays) using a suntest simulator. The phototransformation of the parent compound was followed by HPLC technique. The photodegradation process appears to follow the first order reaction. Kinetic parameters were determined and the experimental results show that the photodegradation of these substrates was enhanced in presence of K-montmorillonite, in comparison with Fe(III) exchanged montmorillonite and montmorillonite complexed with humic acid complexes. This study has shown that the iron and humic acid adsorbed on clay surfaces did not increase the degradation rate.