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A new biphasic organic solvent, phenoxyethanol-maleic acid, was carried out to pretreat and fractionate vinegar residue into glucan, xylan and lignin under mild conditions. Additional effects of key factors, temperature and phenoxyethanol concentration, on vinegar residue, were evaluated. Under the biphasic system (0.5% maleic acid, 60% phenoxyethanol), 140 °C cooking vinegar residue for 1 h, 80.91% of cellulose retention in solid residue, 75.44% of hemicellulose removal and 69.28% of lignin removal were obtained. Optimal identified conditions resulted in maximum XOS of 47.3%. Then, the solid residue was enzymatically digested with a glucose yield of 82.67% at 72 h with the addition of 2.5 g/L bovine serum albumin. Finally, the residue was characterized by SEM, FTIR, XRD and BET analysis. This work demonstrated the phenoxyethanol-maleic acid pretreatment yielded XOS, fermentable sugar, and lignin with high processibility.

Due to increasing water scarcity, it is essential to determine cost-effective and efficient methods of producing potable water, especially ones that utilize non-traditional sources. Although reverse osmosis (RO) shows promise as a key-player in mitigating water scarcity, it is limited by biofouling. It is therefore integral to identify effective antifoulants that also do not damage the membrane, cause resistance, or negatively impact human health and the environment. Potential antifoulants include preservatives used in home and personal care products. It is hypothesized that safer preservatives can be applied to RO systems to remove or prevent biofouling. Three preservatives including methylisothiazolinone (MIT), phenoxyethanol (PE), and sodium benzoate (SB) were tested via antimicrobial susceptibility tests against P. aeruginosa biofilms grown in 96-well plates to investigate both biofilm prevention and biofilm removal. Data were collected in the form of minimum biofilm inhibitory concentration (MBIC) and minimum biofilm eradication concentration (MBEC), respectively. MIT was the most effective of the three preservatives but also poses the highest hazard to human health and the environment. Due to efficacy and safety concerns, MIT, PE, and SB are not the final solution; however, a process was demonstrated for determining the efficacy of novel, safer antifoulants. Ultimately, further investigations into safer antifoulants, paired with a greater understanding of biofilm removal and prevention doses will help make RO a better solution for water scarcity.

The aim of this study was to assess the analgesic efficacy of sufentanil in dressings after surgical treatment of burn wounds.Twenty adult patients, who underwent surgical treatment of third-degree burn wounds under general anesthesia, were included. Two of the patients underwent surgery twice. During surgery, patients received 50-100 μg fentanyl every 20-30 min and, after surgery, patients received 100 mg ketoprofen twice daily. Additionally, ten patients (group 1) received 50 μg sufentanil added to the burn wound dressings soaked in octenidine and phenoxyethanol while 10 patients (group 2) received 25 μg sufentanil added to the same dressings. The rescue analgesic, which was administered when pain intensified, was 5 mg subcutaneous morphine. Plasma sufentanil concentrations were assayed at 1, 2, 3, and 6 h after surgery completion and when pain was reported, along with pain intensity evaluation.Sufentanil was not detected in the serum of any patients. Rescue morphine was given during the postoperative period (24 h) in one patient in group 1 (who underwent surgery twice) and three patients in group 2. The mean sufentanil concentration in dressings was higher in group 1 (0.13 ± 0.03) than group 2 (0.06 ± 0.03 μg/mL; p0.001). The group 1 patient who received rescue morphine had a sufentanil concentration of 0.10 μg/mL, which was the lowest concentration in group 1. Group 2 patients who received rescue morphine had sufentanil concentrations of at least two-fold lower (0.03-0.05 μg/mL). No adverse effects were observed.Sufentanil in dressings after burn wound surgery provides effective and safe analgesia and the sufentanil concentration in dressings should be ≥0.10 μg/mL in a solution of octenidine and phenoxyethanol.

The most common skin disorder is acne (Acne vulgaris) which is a chronic inflammatory disease that occurs in the pilosebaceous unit. Infection can be caused by Propionibacterium acnes and Staphylococcus aureus. Moringa leaves are known to inhibit acne growth. Piper crocatum leaves are also thought to have antibacterial activity. The study aims to determine the effect of the combination of the two extracts in inhibiting the growth of acne-causing bacteria, also tested the gel formula to meet physical and chemical parameters as well as stability to temperature and storage, also to test the acute dermal irritation against rabbit. Each extract with a concentration of 0.3%; 0.6%; 1.25%; 2.5%; 5%; 10%; 20%, incubated then measured the inhibition zone, then determined the minimum inhibition zone concentration of the two extracts to determine the lowest levels of the extracts which still gave antibacterial activity against the tested bacteria by the well diffusion method. The extract combination was formulated in a gel preparation with the excipients Carbopol 940, PG, Phenoxyethanol, TEA, CMC, and Aquadest. Antibacterial activity test for gel preparations used the well method with positive control Medi-Klin® gel. Then the formula evaluation includes physical, chemical, and microbiological evaluations. The results showed that the combination gel form had activity against P. acne and S. aureus at concentrations of 2.5% : 2.5%. The combination gel preparation of the two extracts also has synergistic effect in inhibiting acne bacteria. The formula can meet physical and chemical parameters and is stable to temperature and storage.

Triggering factors of sensitive skin are supposed to be physical, chemical (cosmetics, water, and pollutants), and occasionally psychological (stress). A recent meta-analysis showed that the most important triggering factor declared by subjects is the use of cosmetics. This study was designed to compare the consumption of cosmetic products in women with sensitive skin and controls. After a dermatological examination, women between the ages of 18 and 65 years with or without sensitive skin were recruited. They completed different questionnaires about the presence of sensitive skin and use of 28 cosmetics that could be applied on the face. The amount per application was recorded for all products used at least once a week on the face. In total, 160 women were included, with a mean age of 41 ± 13 years. Two groups of 40 women were created based on the sensitive scale (SS-10 score), with the lowest SS-10 scores (nonsensitive skin group) and the highest SS-10 score (sensitive skin group). The number of products used daily was similar in the 2 groups. Women with sensitive skin were significantly more frequent users of liquid soap/soap-free gel cleansers than those without sensitive skin (70 vs. 43%). There was no difference concerning the frequency of use of products in the 2 groups. Concerning the amount of product used by application, women with sensitive skin used twice as much cream per application compared with the women without sensitive skin: 511 ± 438 μg versus 290 ± 203 μg (p = 0.039). Concerning the composition of the cosmetic products used, the only difference concerned phenoxyethanol, which was more often present in the moisturizer of women without sensitive skin (66.7%) than in those with sensitive skin (32.4%) (p = 0.007). Women with sensitive skin were more likely to buy products recommended for sensitive skin by manufacturers. The relationship of causality between the use of cosmetics and sensitive skin cannot be established. Women with sensitive skin used different cosmetic products than women without sensitive skin. Women with sensitive skin used a higher amount of moisturizer, used products recommended for sensitive skin, and bought more cosmetic products at pharmacies than supermarkets. We hypothesized that subjects with sensitive skin are looking for products that improve the sensation of skin sensitivity.

A new, simple and rapid method for the quantitative determination of the antimicrobial preservative 2-phenoxyethanol, based on reverse phase ultra-high-performance liquid chromatography has been developed. The validation was performed according the ICH Q2 guideline “Validation of Analytical Procedures”. The desired chromatographic separation was achieved on a Waters Symmetry C18 (150 × 4.6 mm, 5 μm) column using an isocratic elution, with detection at 270 nm wavelength. The mobile phase consisted of acetonitrile/water (55:45, v/v), pumped at a flow rate of 1 mL/min. The calibration curve and the analytical procedure are linear (r2 = 0.999) from the concentration of 0.07 mg/mL to 1.1 mg/mL. The percent relative standard deviation for intra- and inter-day precision was

Microbiological stability of medicines is an integral part of their quality, therefore, at the stage of pharmaceutical development, the issues of ensuring microbiological purity should be considered. To this end, various chemicals are added to the composition of semisolid medicines that actively inhibit the growth of microorganisms that enter the pharmaceutical system during production and reuse. Insufficient amount of a preservative can lead to the adaptation of microorganisms, and excess- to increase the toxicity of the drug. In the development of the composition of the anti-allergic action gel containing dimethindene maleate and dexpanthenol in order to select a preservative and its concentration, the following antimicrobial substances have been chosen: phenoxyethanol, benzalkonium chloride, methylparahydroxybenzoate (nipagin, E218), propylparahydroxybenzoate (nipasol, E216) and potassium sorbate (E202). The purpose of this work is to evaluate the effectiveness of these antimicrobial preservatives in the composition of the gel under study. For microbiological studies 5 samples have been developed: N 1 – gel + phenoxyethanol 0.75%; N 2 – gel + benzalkonium chloride 0.015%; N 3 – gel + nipagin 0.15% + nipasol 0.05%; N 4 – gel + potassium sorbate 0.2%; N 5 – gel without preservatives added. The research used the method for evaluating the effectiveness of antimicrobial preservatives given in SPU 2.0 (Section 5.1.3). As a result of the experiment, it has been determined that the sample of gel without preservative does not meet the requirements of SPU and proved the need to add antimicrobial preservatives to the composition of the developed gel. The results of the study for samples with preservatives phenoxyethanol 0.75%, benzalkonium chloride 0.015%, nipagin 0.15% + nipasol 0.05% completely meet the requirements of SPU on the indicator «antimicrobial effectiveness of preservatives» for medicinal products for external use. An experimental study of the sample with a potassium sorbate 0.2% preservative showed that it did not fully meet the requirements of the above article of SPU. Among the samples that meet the requirements of SPU, the highest antimicrobial efficacy against strains of Staphylococcus aureus ATCC 6538, Pseudomonas aeruginosa ATCC 9027, Candida albicans ATCC 885-653, Aspergillus brasiliensis ATSC 16404 has shown a sample of 0.75% phenoxyethanol preservative (N 1). Therefore, for further microbiological studies, samples of gels with phenoxyethanol concentrations of 0.5%, 0.75% and 1.0% were prepared and the antimicrobial efficacy of these samples has been studied. Based on experimental studies, it has been found that 0.75% is the optimal concentration of phenoxyethanol in the composition of gel containing dimethidene maleate and dexpanthenol. Thus, a complex of studies has been conducted to prove the antimicrobial effectiveness of the phenoxyethanol preservative and its concentration.

Background Preservatives represent one of the main causes of skin irritation and contact allergies. Aims To comprehensively evaluate the skin irritation potential of phenoxyethanol, methylparaben, propylparaben, imidazolidinyl urea, and DMDM hydantoin under regulatory acceptable concentrations. Methods A patch test and repeated open application test (ROAT) were applied to evaluate skin irritation in vivo. In vitro alternative methods consisting of the keratinocyte cytotoxicity assay, red blood cell (RBC) test, and hen's egg test-chorioallantoic membrane (HET-CAM) were performed to elucidate the mechanism of preservative-induced irritation responses. Results The patch test showed that all test substances showed a weak erythema response. Propylparaben had the highest occlusive irritancy potential in the patch test, owing to damage to the cell membrane. The two formaldehyde releasers showed noticeable skin irritation potential in the ROAT through their cytotoxicity to keratinocytes, while a visible response was observed after applying phenoxyethanol and the two parabens. No filtration was noticed in the in vivo tests, which might be attributed to the failure of subcutaneous vessel alteration by the preservatives. Conclusions Commonly used cosmetic preservatives have minor skin irritation potential with mild erythema reaction under practical use, especially formaldehyde releasers and propylparaben.

A prerequisite for ensuring the quality of medicines is their production in accordance with the rules of GMP (Good Manufacturing Practice for Medicinal Products), one of the most important requirements of which is equipment cleaning. Modern disinfectants that are used for the sanitary processing of technological equipment are multicomponent. These include not only the active substances of disinfectants, but also surfactants, stabilizers. In case of violation of the regimes of final washing of these agents from the surfaces of technological equipment, there is a possibility of their introduction into pharmaceutical products. This problem in Ukraine is practically unexplored due to the lack of effective methods for determining the microconcentrations of disinfectants. Washing and disinfecting agent «Incidin Pro» (active ingredients: N,N-bis- (3-aminopropyl) dodecylamine, benzalkonium chloride, phenoxyethanol) is used to clean pharmaceutical equipment. A risk analysis was carried out and a component for detecting residual amounts of this agent – phenoxyethanol (MAСO – 2.9 μg/ml) was determined. The aim of this work is to develop an easy-to-use, express, selective HPLC method for determining residual amounts of phenoxyethanol in washes. Object of study – phenoxyethanol – a component of washing and disinfecting agent «Incidin Pro». For quantitative determination, high performance liquid chromatography was used. Chromatography was performed on an Agilent 1260 Infinity 2D LC System liquid chromatograph (USA) with a UV detector. The optimal conditions for the analysis were experimentally established: chromatographic column (0.10 m x 4.6 mm, filled with octadecylsilyl silica gel for chromatography (3.5 μm)), eluent composition and its gradient, column temperature (30 °C), wavelength (210 nm) and detection time are required to ensure that all components (including excipients) are exited from the column, selective determination of phenoxyethanol, and minimization of analysis time. The methodology is validated by the following parameters: specificity, linearity, limit of quantification. The specificity of the method is based on the ability to reliably determine the content of phenoxyethanol in the washes, which is achieved by using an external standard. The calibration graph shows that the detection limit of phenoxyethanol is 0.04 μg/ml. The developed method can be recommended for determination of residual quantities of phenoxyethanol in quality control of cleaning of pharmaceutical equipment.

Embalming fixatives such as formaldehyde and phenol have been associated with occupational health hazards. While anatomists aim at replacing these chemicals, this seems presently unfeasible in particular for formaldehyde. Furthermore, fixation protocols usually require well‐equipped facilities with highly experienced staff to achieve good fixation results in spite of only a minimal use of formaldehyde. Combining these aspects, a technique robust enough to be carried out by morticians is presented, resulting in durable tissues with minimal formaldehyde use. An embalming protocol involving phenoxyethanol was established, using concentrations of 7 and 1.5 Vol% of phenoxyethanol in the fixative and the conservation fluid, respectively. Visual, haptic, histological, and biomechanical properties and their perceived potential to positively influence student learning outcomes were compared to standard embalming techniques. The phenoxyethanol technique provides esthetic, durable, and odorless tissues. Bleaching is less pronounced compared to ethanol‐ or formaldehyde‐based protocols. The tissues remain pliable following the phenoxyethanol‐based embalming and can be used for biomechanical experiments to some extent. Phenoxyethanol‐fixed tissues are well suited for undergraduate teaching with perceived positive learning outcomes and partly for postgraduate training. Phenoxyethanol tissues provide the option to obtain well‐preserved histology samples, similar to those derived from formaldehyde. The provided protocol helps replace the use of phenol and formaldehyde for conservation purposes and minimizes the use of formaldehyde for the initial injection fixation. Phenoxyethanol‐based embalming forms an effective alternative to standard embalming techniques for human cadavers. It is simple to use, allowing fixation procedures to be carried out in less sophisticated facilities with non‐anatomy staff.

BACKGROUND Preservatives in cosmetics are often suspected as contact sensitizers and hence frequently patch tested in dermatitis patients. Exposure in this field has changed over the course of years. OBJECTIVE To describe the frequency of contact sensitization to various preservatives. MATERIALS AND METHODS Retrospective data analysis from the Information Network of Departments of Dermatology (IVDK) for the years 2009-2018. RESULTS Frequency of sensitization to methylisothiazolinone (MI) has increased from 2.0% in 2009 to 7.2% in 2013. Since 2014, the rate has been falling again. Increasing the patch test concentration of methyldibromo glutaronitrile (MDBGN) in 2016 has caused a sudden rise in positive patch test reactions from 2.0% to more than 4.5%. Allergic reactions to other preservatives occurred in less than 1% of the patients tested. DISCUSSION Since 2014, the worldwide "epidemic" of sensitization to MI has been subsiding in Central Europe, thanks to corresponding restrictions on use. Since 2008, there is no longer any widespread exposure to MDBGN; the new, higher test concentration elicits many false-positive test reactions and explains the sudden rise in positive patch test reactions since 2016. Despite widespread use, phenoxyethanol, benzoates, benzyl alcohol, parabens and sorbates rarely cause allergic reactions. Therefore, they can be recommended for cosmetics from the epidemiological-allergological point of view.

The advantages and disadvantages of modern antiseptics for local treatment and prevention of wound infections are considered. On the basis of data of comparative clinical studies the advantages of topical drugs based on octenidine dihydrochloride in combination with phenoxyethanol are presented. The advantages of octenidine dihydrochloride/ phenoxyethanol as a local antiseptic for treatment and prevention of wound infections in case of wound defects, burns are described.

Background Ethylhexylglycerin (EHG) is a recently recognized contact allergen. Objective The aims of the study were to characterize individuals with positive patch test reactions to EHG and to analyze reaction strength, clinical relevance, and allergen sources. Methods This study was a retrospective analysis of the patients patch tested to EHG (5% petrolatum) by the North American Contact Dermatitis Group (2013-2018). Results Of 15,560 patients tested to EHG, 39 (0.25%) had positive (final interpretation of "allergic") reactions. Most were female (71.8%) and/or older than 40 years (76.9%). There were no statistically significant differences between age, sex, or atopic history when compared with EHG-negative patients. The most common anatomic sites of dermatitis were the face (28.2%) and scattered generalized distribution (25.6%). Most EHG-positive reactions were + (35.9%) or ++ (33.3%). Current clinical relevance was high (79.5%); none, however, were related to occupation. Personal care products were the most common source of exposure to EHG (59.0%). Conclusions Ethylhexylglycerin is a rare contact allergen; the positive frequency of 0.25% is similar to other low allergenic preservatives including parabens, benzyl alcohol, and phenoxyethanol. The patch test concentration of 5.0% seems to be nonirritating. Although relatively uncommon, EHG reactions were usually clinically relevant (79.5%), often because of moisturizers/lotions/creams.

Background/objectives Allergic contact dermatitis, photoallergic contact dermatitis and irritant reactions to sunscreens are common reasons for dermatology consultation. Patch testing for contact allergy relies on up-to-date knowledge of allergen exposures. The aim of this study was to investigate contact allergens and photoallergens in sunscreens commercially sold on the shelves of supermarkets and pharmacies in New Zealand. Methods A comprehensive market data review of suppliers' websites was performed from March to August 2019 to obtain a list of the commonly sold sunscreens in our region. Ingredients were collated and analysed according to International Nomenclature of Cosmetic Ingredients (INCI) names. Ultraviolet (UV) filters, preservatives and fragrances were included for analysis. Place of sale and cost of sunscreens were also recorded. Results Ninety-five sunscreens were analysed: 36% sold in supermarkets, 43% in pharmacies and the remainder available in both. The most frequent UV filters were butyl methoxydibenzoylmethane (contained in 70% of products) followed by octocrylene (63%) and homosalate (50%). The common photoallergen benzophenone 3 was found in 19% of products. Phenoxyethanol was the most common preservative (68%) followed by disodium EDTA (30%) and propylparaben (26%). Two sunscreens contained methylisothiazolinone. Sixty-one per cent contained at least one fragrance, the most frequent being limonene (17%) and linalool (13%). There was an average of 1.1 New Zealand baseline series allergens per product (range 0 to 6, standard deviation 1.27). Conclusion Common allergens including those with high sensitising potential were frequently found in New Zealand sunscreen. Knowledge of ingredients used by manufacturers is useful in dermatological assessment of skin contact reactions.

Over the last two decades, significant advances have been made in developing disposable baby wet wipes. Wet wipes consist of two main components: nonwoven fabric and liquid. Being more than 90% water, wet wipes are more susceptible to microbial growth than typical personal care products, hence, high concentrations of preservative compounds are often used to ensure extended protection against contamination. However, there is an obvious tendency to minimize the concentration of irritating actives. Baby wet wipes should contain particularly mild surfactants, well-tolerated preservatives, and a buffer system maintaining the formulation pH at a suitable level for the infant’s skin. Efforts have been centered on removing ingredients with irritation potential, such as phenoxyethanol. In addition, a move towards more natural fabrics is occurring. However, these modifications provoke new challenges in preserving the final products. The nature and composition of the fiber can influence the interactions between the preservative and the wipe, subsequently affecting the performance of the preservative system. In this study, we analyzed the causes of the challenge in preserving wet wipes. We found that fabrics containing natural fibers are the main source of contamination, promoting the generation of biofilms on their surfaces. Moreover, the hydrophilic–lipophilic balance (HLB) was utilized to rationalize the physicochemical interactions between the fabric and the preservatives.

Preservative efficacy testing (PET) is a fundamental practice in industrial microbiology used to ensure product shelf-life and quality. To improve on current growth-based PET, bioluminescence was evaluated as a real-time bacterial viability indicator using Pseudomonas aeruginosa . Random mutagenesis of an industrial P. aeruginosa strain with a promoter-less luxCDABE mini-Tn5 was used to select a stable reporter (LUX12H5) with an un-altered growth and preservative susceptibility phenotype. Bioluminescence and viability were measured with and without preservatives (isothiazolinones, phenoxyethanol, and dimethyl dimethylol hydantoin) and an antibiotic comparator (ciprofloxacin). In the absence of antimicrobials, a good correlation between bioluminescence and viability (r2=0.92) was established. However, metabolic inhibition by isothiazolinone preservatives caused a rapid decline in light output that did not correlate to a reduced viability. Conversely, after ciprofloxacin exposure, the decline in viability was greater than that of bioluminescence. A positive attribute of the bioluminescence was the early detection of metabolic recovery and re-growth of preservative injured bacteria. Overall, while initial bioluminescence read-outs were less suited to current PET requirements, it shows promise as an early, direct indicator of bacterial regrowth in the context of long-term evaluation of preservative efficacy.

Pharmaceutical grade bentonite, containing a high amount of montmorillonite, enriched with zinc (Zn) or copper (Cu) (ZnBent and CuBent, respectively) was used as the main component for the creation of formulations for cutaneous use and tested for their antimicrobial capacity. Bentonite (Bent) with added phenoxyethanol (PH) as a preservative and unmodified bentonite were used as control groups. The mineralogical composition, structural state, and physical or chemical properties, before and after the modification of the samples, were characterized utilizing X-ray Diffraction Analysis (XRD), Fourier-Transform Infrared Spectroscopy (FTIR) and X-ray Fluorescence (XRF) techniques, and Scanning Electron Microscope-Energy Dispersive Spectroscopy (SEM, SEM-EDS) analyses. In addition, the profile of zinc and copper concentration from two types of surfaces ZnBent and CuBent, and into Phosphate-Buffered Saline (PBS) are discussed. Finally, the formulations in the form of basic pastes were challenged against bacteria, molds, and yeasts, and their performance was evaluated based on the European Pharmacopeia criteria. The Cu-modified bentonite performed excellently against bacteria and yeasts, while the Zn-modified bentonite only showed great results against yeasts. Therefore, Cu-modified bentonite formulations could offer antimicrobial protection without the use of preservatives.

Pathogen microorganisms detection, such as Staphylococcus aureus (S. aureus), is so critical because it can be dangerous for public health. In this research, we have tried to introduce a simple and sensitive modified biosensor by multiwalled carbon nanotubes (MWCNTs) for S. aureus PTCC 1112 detection which was inoculated in PBS (pH 7.4). The pulsed amperometric detection (PAD) method showed that by increasing the concentration of S. aureus suspension, the related current will increase linearly in a dynamic range of 1.88 × 107–3.00 × 108 cfu mL−1, with a detection limit of 4.85 × 105 cfu mL−1. The antibacterial effect of three herbal essential oils, tea, bergamot and lemon, and three common chemical cosmetic preservatives, euxyl (phenoxyethanol:ethylhexylglycerin), benzyl alcohol and benzalib (alkyl benzyl dimethyl ammonium chloride), was compared by electrochemical and biological methods. The results based on disk diffusion agar method and PAD revealed that this biosensor can be used for comparing the effectiveness of natural and chemical preservatives to inhibit the growth of bacteria. By adding the essential oils into the S. aureus suspension in PBS, the related currents were largely decreased about 65.83% (green tea), 80.49% (bergamot) and 93.30% (lemon) that are in agreement with the inhibition zones of microbial test and comparable to chemical preservatives of euxyl (73.52%), benzyl alcohol (90.65%) and benzalib (93.81%). It demonstrates the comparative antibacterial effect of these essential oils versus chemical preservatives and the ability of MWCNTs/GCE to detect the presence or absence of S. aureus in a few minutes.

The article presents the literature data and the authors’ own observations on the current state of the issue in the clinical use of octenidine dihydrochloride and phenoxyethanol in thermal burns of the skin in clinical and outpatient surgery.

BackgroundPreservativesare often necessary components of commercial products. Large-scale North American studies on preservative allergy are limited.ObjectiveTo evaluate demographics, positive patch test reactions (PPTRs), clinical relevance, and trends for preservatives tested by the North American Contact Dermatitis Group.MethodsWe conducted a retrospective cross-sectional analysis of North American Contact Dermatitis Group patch testing results of preservatives from 1994 through 2016.ResultsA total of 50,799 patients were tested; 11,338 (22.3%) had a PPTR to at least 1 preservative. The most frequent reactions were to methylisothiazolinone 0.2% aqueous (aq) (12.2%), formaldehyde 2% aq (7.8%), formaldehyde 1% aq (7.8%), quaternium-15 2% petrolatum (pet) (7.7%), and methyldibromo glutaronitrile/phenoxyethanol 2% pet (5.1%). Paraben mix 12% pet (1%), iodopropynyl butylcarbamate 0.1% pet (0.4%), benzyl alcohol 1% pet (0.3%), and phenoxyethanol 1% pet (0.2%) had the lowest PPTRs. Linear regression analysis of preservatives tested showed that only methylchloroisothiazolinone/methylisothiazolinone 0.01% aq (parameter estimate, 0.42; 95% CI, 0.17-0.66; P&nbsp

BACKGROUND Methyldibromoglutaronitrile/phenoxyethanol (MDBGN/PE) is a broad-spectrum preservative mixture used in consumer and industrial products. OBJECTIVES The aims of the study were (1) to characterize the prevalence and clinical relevance of patch test reactions to MDBGN/PE and the epidemiology of positive patients and (2) to determine the frequency of concomitant reactions of MDBGN/PE and its components. METHODS This study used a retrospective analysis of cross-sectional data compiled by the North American Contact Dermatitis Group from 1994 to 2018. RESULTS Of 55,477 tested patients, 2674 (4.8%) had positive patch test reactions to MDBGN/PE (1.0%-2.5% petrolatum [pet]); most were + (63.3%) or ++ (22.3%). Clinical relevance was considered definite in 3.0% and probable in 19.3% of reactions. Common dermatitis sites included the hands (26.4%), scattered/generalized distribution (24.7%), and the face (18.3%). Patients with a positive reaction to MDBGN/PE and/or MDBGN and/or PE were significantly more likely to be male and older than 40 years and/or had hand dermatitis (P ≤ 0.0033). Positivity to MDBGN/PE 2.0% pet decreased significantly over time (from 6.0% in 1998-2000 to 2.5% in 2017-2018, P < 0.0001). Personal care products were the most common exposure source (53.2%). CONCLUSIONS Over time, positivity to MDBGN/PE 2.0% pet decreased significantly from 6.0% (in 1998-2000) to 2.5% (in 2017-2018). The high proportion of weak (63.3%) reactions underscore the need for careful interpretation of patch test sites. Important demographic associations included male sex and age older than 40 years.

Background Preservatives are often necessary components of commercial products. Large-scale North American studies on preservative allergy are limited. Objective To evaluate demographics, positive patch test reactions (PPTRs), clinical relevance, and trends for preservatives tested by the North American Contact Dermatitis Group. Methods We conducted a retrospective cross-sectional analysis of North American Contact Dermatitis Group patch testing results of preservatives from 1994 through 2016. Results A total of 50,799 patients were tested; 11,338 (22.3%) had a PPTR to at least 1 preservative. The most frequent reactions were to methylisothiazolinone 0.2% aqueous (aq) (12.2%), formaldehyde 2% aq (7.8%), formaldehyde 1% aq (7.8%), quaternium-15 2% petrolatum (pet) (7.7%), and methyldibromo glutaronitrile/phenoxyethanol 2% pet (5.1%). Paraben mix 12% pet (1%), iodopropynyl butylcarbamate 0.1% pet (0.4%), benzyl alcohol 1% pet (0.3%), and phenoxyethanol 1% pet (0.2%) had the lowest PPTRs. Linear regression analysis of preservatives tested showed that only methylchloroisothiazolinone/methylisothiazolinone 0.01% aq (parameter estimate, 0.42; 95% CI, 0.17-0.66; P Limitations Collected variables are dependent on clinical judgment. Results may be prone to referral selection bias. Conclusions This large North American study provides insight on preservative PPTRs and trends from 1994 through 2016.

Made available in DSpace on 2021-06-25T11:12:13Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-01-01 The safety assessment of cosmetic products is based on the safety of the ingredients, which requires information on chemical structures, toxicological profiles, and exposure data. Approximately 6% of the population is sensitized to cosmetic ingredients, especially preservatives and fragrances. In this context, the aim of this study was to perform a hazard assessment and risk characterization of benzalkonium chloride (BAC), benzyl alcohol (BA), caprylyl glycol (CG), ethylhexylglycerin (EG), chlorphenesin (CP), dehydroacetic acid (DHA), sodium dehydroacetate (SDH), iodopropynyl butylcarbamate (IPBC), methylchloroisothiazolinone and methylisothiazolinone (MCI/MIT), methylisothiazolinone (MIT), phenoxyethanol (PE), potassium sorbate (PS), and sodium benzoate (SB). Considering the integrated approaches to testing and assessment (IATA) and weight of evidence (WoE) as a decision tree, based on published safety reports. The hazard assessment was composed of a toxicological matrix correlating the toxicity level, defined as low (L), moderate (M), or high (H) and local or systemic exposure, considering the endpoints of skin sensitization, skin irritation, eye irritation, phototoxicity, acute oral toxicity, carcinogenicity, mutagenicity/genotoxicity, and endocrine activity. In a risk assessment approach, most preservatives had a margin of safety (MoS) above 100, except for DHA, SDH, and EG, considering the worst-case scenario (100% dermal absorption). However, isolated data do not set up a safety assessment. It is necessary to carry out a rational risk characterization considering hazard and exposure assessment to estimate the level of risk of an adverse health outcome, based on the concentration in a product, frequency of use, type of product, route of exposure, body surface location, and target population. Department of Safety Assessment Grupo Boticário School of Pharmaceutical Sciences UNESP - Univ Estadual Paulista School of Pharmaceutical Sciences UNESP - Univ Estadual Paulista

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Background Chemicals in textile manufacturing and laundering products are important sources of allergens triggering allergic contact dermatitis. Allergens corresponding to the textile production process have been well recognized. However, there is limited information regarding potential allergens in laundering products. Objective The aim is to investigate the presence and prevalence of potential allergens in commonly used laundering products. Methods An Internet-based search was performed to identify the current best-selling laundering products in the United States. Subsequent inquiry of common allergens for each product was collected through a review of ingredients listed by manufacturers. Results Sixty-five laundering products were examined: 30 laundry detergents, 10 fabric softeners, 8 dryer sheets, and 17 stain removers. Ten common allergens were identified: benzisothiazolinone, benzyl benzoate, cocamidopropyl betaine, decyl glucoside, "fragrances," lauryl glucoside, methylisothiazolinone, methylchloroisothiazolinone, phenoxyethanol, and propylene glycol. Fragrances and essential oils are the top allergens in laundry detergents (66.7%), fabric softeners (90%), dryer sheets (75%), and stain removers (58.8%). Laundry detergents labeled as "baby safe" and "free and gentle" contained common allergens, with methylisothiazolinone being the most prevalent, in 80% and 57.1%, respectively. Conclusions Textile dermatitis can negatively impact quality of life and function. Aside from textile dyes and finishing resins, laundering products should also be considered.

Parabens are widely used as preservatives in the last decades. Others preservatives such as 2-phenoxyethanol, which in addition to his good antimicrobial activity, has low allergenic potential as well others properties of interest to the cosmetic industry. In this work was developed a method for determination of methylparaben (MP), propylparaben (PP) and 2-phenoxyethanol (FE) in cosmetic products by HPLC-DAD using QuEChERS as sample preparation. For application in cosmetic samples, the original QuEChERS method was modified and optimized by evaluate of different solvents for extraction and sorbents for clean up step. Increases at recoveries of analytes were obtained employing acetone as solvent and PSA for clean up step, showed recoveries between 83.7% and 88.6% for all analytes. The method was validated according to ANVISA (linear range: 0.1 to 2.5 µg mL-1 for MP and PP, and 1.5 to 6.0 µg mL-1 for FE). Precision was evaluated by repeatability and intermediate precision with coefficients of variation (%) lower than 10% in all concentrations analysed, and accuracy was evaluated, with values ranging from 93.77% to 108.13%. The QuEChERS-HPLC-DAD method was tested in real samples (moisturizing cream and lotion, cleansing gel), where the concentration values were found below the maximum limit established by ANVISA.

Introduction and objectives Atopic dermatitis (AD) is the most common skin disease among pediatric patients, which affects up to 20% of children worldwide. Characterized by pruritus and eczema, it is also associated with improper skin barrier function and allergen sensitization. Here, we aimed to assess the presence of haptens in emollients marketed in two European countries: in Poland and Spain, as, firstly, these products are considered to be AD's basic therapy, and, secondly, frequent application of potent sensitizers on atopic skin may result in contact dermatitis. Materials and methods We systematically searched for moisturizers explicitly described as “Atopic skin care” products in the most frequently visited online pharmacies in Poland and Spain. Subsequently, we created a database of all products and compared their composition with 139 contact haptens listed in the European Baseline Series (EBS), Fragrance and Cosmetic Series. Results As of December 2018, our list comprised 159 and 111 emollients available on the Polish and Spanish markets, respectively. There were no ingredients listed in 28 (17.5%) products in Poland and 24 (21.6%) in Spain. Only 23 (17.5%) and 13 (14.8%) products were hapten free. The pattern of most common haptens was similar in both countries, including phenoxyethanol, tocopherol and tocopheryl acetate, undefined parfum in Poland and tocopherol, phenoxyethanol, tocopheryl acetate and undefined parfum in Spain. Conclusions This study shows that a vast majority of products taken into consideration contain at least one potential contact hapten. These findings indicate a need for patient education about potentially allergenic ingredients and stronger cooperation between academia and cosmetic manufacturers.

Ink dating is a significant problem in terms of forensic science. Ballpoint pens are generally used as writing tools on the documents. Aging is determination of the changes in dyes and solvents in the composition of ink over time by analytical methods. The evaporation of the solvents from the paper surface is faster than the decomposition process of the dyes. In this study, in 2017, we were asked by the court to determine whether the texts on the suspicious pages of an agenda dated 1996 were written within 2 years or earlier. Phenoxyethanol and dyes were examined in the composition of all suspected ink samples. The results show the determination of both the decomposition process of the dyes and the evaporation process of phenoxyethanol in the aging of the document entries written by ballpoint pen.

A novel ternary solvent system for organosolv fractionation of lignocellulosic biomass, named APW process, which is composed of acetone, phenoxyethanol and water with the advantages of monophasic deconstruction and biphasic separation of components was developed. Through fractionation of amorpha as a case study, a monophasic APW solution (acetone/phenoxyethanol/water = 5:11:4, volume ratio) with the best lignin affinity was constructed based on Hansen solubility parameters. According to Taguchi experimental design, the optimal conditions were 130 °C, 70 min, 0.15 M sulfuric acid and 20 LSR. Under optimal conditions, removal of lignin and hemicellulose reached 95.60% and 98.39%, respectively. While 80.48% of cellulose was retained in residue and its digestibility was 80.36%. Then, 83.74% of hemicellulose was recovered from aqueous as sugars, and 35.64% of lignin was recovered by precipitation. Moreover, APW process also have effective fractionation of sugarcane bagasse, corn cob and pine, cellulose and hemicellulose recovery were both over 80%.

Background Allergic contact dermatitis commonly occurs on the face. Facial cleansing wipes may be an underrecognized source of allergens. Objective The aim of this study was to determine the frequency of potentially allergenic ingredients in facial wet wipes. Methods Ingredient lists from name brand and generic facial wipes from 4 large retailers were analyzed. Results In the 178 facial wipes examined, a total of 485 ingredients were identified (average, 16.7 ingredients per wipe). Excluding botanicals, the top 15 potentially allergenic ingredients were glycerin (64.0%), fragrance (63.5%), phenoxyethanol (53.9%), citric acid (51.1%), disodium EDTA (44.4%), sorbic acid derivatives (39.3%), tocopherol derivatives (38.8%), polyethylene glycol derivatives (32.6%), glyceryl stearate (31.5%), sodium citrate (29.8%), glucosides (27.5%), cetearyl alcohol (25.8%), propylene glycol (25.3%), sodium benzoate (24.2%), and ceteareth-20 (23.6%)/parabens (23.6%). Of note, methylisothiazolinone (2.2%) and methylchloroisothiazolinone (1.1%) were uncommon. The top potential allergens of botanical origin included Aloe barbadensis (41.0%), chamomile extracts (27.0%), tea extracts (21.3%), Cucumis sativus (20.2%), and Hamamelis virginiana (10.7%). Conclusions Many potential allergens are present in facial wet wipes, including fragrances, preservatives, botanicals, glucosides, and propylene glycol.

Blue and green cosmetics are sensitive products for microbial contamination and reducing the contamination producing according to Cosmetic Good Manufacturing Practice (ISO 22716), providing proper storage condition and packaging are effective factors. In addition antimicrobial effective preservatives can be added to protect the cosmetic products. 1,2 Generally, preservatives are chemical substrates that are effective on cytoplasm (conjugation mechanism, ribosomes, nucleic acids, thiol groups, amino groups), cell wall and cytoplasm membrane (membrane potential, enzymes, membrane penetration). 3 The neutralization of the antimicrobial effect of the preservatives in microbiological quality control of cosmetics is essential for the safety of the tests. The antimicrobial preservative in the cosmetic which is transferred to the medium affects the test negatively. The neutralization process can be carried out according to international standards used in microbiological analysis of cosmetic products. The neutralization of preservatives in cosmetics can be performed by adding of neutralizing agents in solvent, medium and/or washing solution. The agents which are reacted with the preservative groups for the removal of antimicrobial affect are used for this neutralization process which is necessary for the removal of antimicrobial effect. According to European Pharmacopeia 2.6.12. sodium bisulfite for glutaraldehyde and mercury compounds; dilution for sorbates and aldehydes; lecithin, polysorbate 80, saponin for quaternary ammonium compounds, parabens and iodines; thioglycollate for mercurial; thiosulfate for halogens can be used as neutralizing agents. 4 Lecithin, polysorbate 80 for parabens, phenoxyethanol, phenylethanol; Lecithin, saponin, polysorbate 80, sodium dodecyl sulphate for quaternary ammonium compounds and cationic surfactants; glycine, histidine for aldehydes formaldehyde - release agents; sodium thiosulphate for oxidizing agents; sodium bisulphate, L-cysteine and thioglycollic acid for metallic salts can be added to the medium, solvent and/or washing solutions according to ISO 21149. 5 For the removal of antimicrobial effect, neutralizing agents in proper concentrations should be added to medium, solvents and washing solutions. The addition of these agents with antimicrobial effect should be proved by the studies of conformity. Neutralizing agents react with antimicrobial agents to eliminate the antimicrobial effect.

Parabens usage as preservatives in cosmetics and personal care products have been debated among scientists and consumers. Parabens are easy to production, effective and cheap, but its safety status remains controversial. Other popular cosmetics preservatives are formaldehyde, triclosan, methylisothiazolinone, methylchloroisothiazolinone, phenoxyethanol, benzyl alcohol and sodium benzoate. Although their high antimicrobial effectiveness, they also exhibit some adverse health effects. Lately, scientists have shown that natural substances such as essential oils and plant extracts present antimicrobial potential. However, their use in cosmetic is a challenge. The present review article is a comprehensive summary of the available methods to prevent microbial contamination of cosmetics and personal care products, which can allow reducing the use of parabens in these products.

Introduction Preservatives are added to cosmetic, household cleaning, and other industrial products to prevent the growth of microorganisms. Unfortunately, exposure to these substances can cause sensitization. Material and methods Between January and June 2015, we analyzed the ingredients of 2300 products commercially available in Spain to identify the frequency of a wide variety of preservatives in different product categories. We analyzed 1093 skin care and cosmetic products sold exclusively in pharmacies (dermocosmetics), 458 household cleaning and personal hygiene and cosmetic products sold in supermarkets, 636 topical medications, and 113 cosmetic products sold in a herbal shop. Results Phenoxyethanol, citric acid, sodium benzoate, and potassium sorbate were very common in all the cosmetic product categories. Parabens were present in 16.1% of dermocosmetic products, 14.45% of cosmetic products available in supermarkets, 0.88% of cosmetic products available in the herbal shop, 5.18% of topical medications, and in none of the cleaning products. Isothiazolinones were identified in 2.56% of dermocosmetic products, 18% of cosmetic products in supermarkets, 7.9% of cosmetic products in the herbal shop, 63.63% of household cleaners, and in none of the topical medications. Formaldehyde releasers were detected in 5.76% of dermocosmetic products, 6.42% of cosmetic products sold in supermarkets, 7.96% of cosmetic products sold in the herbal shop, 3.93% of topical medications, and 16.74% of household cleaners. Conclusions Evaluation of the presence of preservatives in everyday products allows us to indirectly estimate exposure levels to each one. Measures restricting the use of the most problematic preservatives need to be strengthened.

Introduction: The skin of newborns and infants is not fully developed, therefore, it seems particularly important to use in this group products that are safe and free from sensitizing ingredients. Aim of the study: An analysis of skin care products for newborns and infants available on the Polish market with regard to the presence of ingredients with known sensitizing potential. Material and methods: Declared contents of 106 skin care products for newborns and infants: 72 ‘leave-on’ and 34 ‘rinse-off’ cosmetics were analysed for the presence of ‘problematic’ fragrances and preservatives as listed in the Cosmetics Directive (Annex III and VI). Results: Three hundred and sixty-five unique substances including 35 ‘problematic’ substances were identified: 15 (4.1%) fragrances and 20 (5.5%) preservatives. At least one ‘problematic’ fragrance occurred in 91 (85.8%) products, most frequent was linalool, at least one ‘problematic’ preservative occurred in 55 (51.9%), phenoxyethanol was most frequent. Fragrance compositions of undisclosed ingredients hidden under a general cryptonym ‘Parfum’/’Fragrance’ were present in 88 (83%) cosmetic products. Among the analyzed preparations, only 7 (6.6%) did not contain substance with known sensitizing potential. Conclusions: Almost all skin care products for newborns and infants contain ingredients of known sensitizing potential. Most products also contain fragrance compositions hidden under a general cryptonym ‘Parfum’/’Fragrance’ which makes an assessment of their safety profile impossible. The presence of ‘problematic substances’ in almost all cosmetics for newborns and infants confirms the need for further analysis, preventive measures and education of parents and physicians on the dangers of cosmetics use in children.

Background Wet wipes are a significant allergen source for anogenital allergic contact dermatitis. Objective The aim of the study was to calculate the frequency of potentially allergenic ingredients in personal hygiene wet wipes. Methods Ingredient lists from brand name and generic personal hygiene wet wipes from 4 large retailers were compiled. Results In the 54 personal hygiene wet wipes evaluated, a total of 132 ingredients were identified (average of 11.9 ingredients per wipe). The most common ingredients were Aloe barbadensis (77.8%), citric acid (77.8%), fragrance (72.2%), sorbic acid derivatives (63.0%), tocopherol derivatives (63.0%), glycerin (59.3%), phenoxyethanol (55.6%), disodium cocoamphodiacetate (53.7%), disodium ethylenediaminetetraacetic acid (EDTA) (42.6%), propylene glycol (42.6%), iodopropynyl butylcarbamate (40.7%), chamomile extracts (38.9%), sodium benzoate (35.2%), bronopol (22.2%), sodium citrate (22.2%), lanolin derivatives (20.4%), parabens (20.4%), polyethylene glycol derivatives (18.5%), disodium phosphate (16.7%), dimethylol dimethyl hydantoin (DMDM) (14.8%), and cocamidopropyl propylene glycol (PG)-dimonium chloride phosphate (11.1%). Of note, methylisothiazolinone (5.6%) was uncommon; methylchloroisothiazolinone was not identified in the personal hygiene wet wipes examined. Conclusions There are many potential allergens in personal hygiene wet wipes, especially fragrance and preservatives.

Parabens and phenoxyethanol are chemical compounds widely used as preservatives and antimicrobial agents in cosmetic and personal care products. The issue of their effect on human and environmental health is a particularly topical and relevant one that many national and international agencies reported about the risk from the use of such compounds. In the present paper, iron doped TiO2 nanoparticles were synthetized and characterized by morphological and spectroscopic techniques. The proposed synthesis was designed to improve the photocatalytic activity of the nanostructures towards the two preservatives compounds when irradiated by a visible light, in order to optimize the effect of natural irradiation on the photodegradation of the two compounds. Preliminary photocatalytic tests showed that the analytes’ concentration in water solutions under illumination in presence of both iron-doped TiO2 and pure TiO2 decreased. A sensible enhancement of photocatalysis of both propylparaben and phenoxyethanol was recorded in presence of the Fe-doped nanostructures as a consequence of the physical and chemical properties of the catalyst.

SummaryBackground In 2016, dermatologists in Finland suspected contact allergy in several patients using moisturizers under the trade name Apobase®. Following a formulation change, Phenostat™, which is a mixture of phenoxyethanol, caprylhydroxamic acid, and methylpropanediol, was used as a preservative in Apobase® moisturizers in Finland. Objectives To confirm the suspected contact allergy to Apobase® cream, oily cream, and/or lotion, and to identify the specific contact allergen and define its optimal patch test concentration. Methods Thirty-nine patients with suspected contact allergy to Apobase® creams or lotion were patch tested in four Finnish dermatological clinics. The patch tests included old and new Apobase® formulas and their preservative agents: phenoxyethanol, methylpropanediol, and dilution series of Phenostat™ and caprylhydroxamic acid or its potassium salt. Results The patch tests showed positive reactions to the new Apobase® formulas, Phenostat™, and caprylhydroxamic acid or its potassium salt, but not to the old Apobase® formulas, methylpropanediol, or phenoxyethanol. Conclusions We found a new contact allergen, caprylhydroxyamic acid, which caused an epidemic of allergic contact dermatitis in patients using moisturizers containing this preservative. Whether the sensitizing capacity of caprylhydroxamic acid depends on the other chemicals used in Apobase® moisturizers needs further investigation.

Octenidine dihydrochloride is an effective antiseptic compound which mode of action is based on destabilization plasma membrane of microorganisms. This ensures that microorganisms cannot develop the drug resistance in a straightforward way, as the entire cellular structure, rather than specific molecular target is affected. Since the octenidine is a hydrophobic compound, it requires organic solvent such as phenoxyethanol in order to be effectively administered. However, the presence of phenoxyethanol has strong irritating effect, particularly when applied on open wounds and mucous membranes. Phospholipids are known as neutral excipients free of side effects and in their aggregated form may serve as solvent for octenidine. In this article, we propose a new antiseptic formulation composed of equimolar ratio of lipids and octenidine. The resulting particles are ∼4 nm in diameter showing that their topology is different from that known for liposomes. The new formulation has proven to be equally effective as octenidine dihydrochloride formulation marketed under the name of Octenisept®. The main advantage of the new formulation is that it does not contain phenoxyethanol, which opens new possibilities for broader application spectrum of octenidine, including treatments of mucous membranes and open wounds.

Background Preservatives are known causes of allergic contact dermatitis. Objective The aim of this study was to determine the prevalence of preservatives in each product category in the Contact Allergen Management Program and compare prevalence with reported rates of allergic contact dermatitis. Methods Contact Allergen Management Program product information was queried based on the 53 approved preservatives for cosmetic products by the European Union and Association of Southeast Asian Nations plus 5 additional preservatives used in US products. Results Phenoxyethanol and parabens were the most common preservatives with 23.9% of products containing phenoxyethanol and 20.75% of products containing parabens. Methylisothiazolinone (MI) was found in 12.9% of products, most commonly in hair care and household products. Preservatives like MI and methylchloroisothiazolinone (MCI) that are both common in products and have a high incidence of allergic contact dermatitis are of greatest concern as contact allergy hazards. Phenoxyethanol and parabens are common and have weak sensitizing power, making them preferred preservatives. Conclusions Evaluating the prevalence of preservatives provides important information on allergen exposures. Using current positive reaction rates, the risk of sensitization to a given preservative can be more accurately estimated and may affect the use of certain preservatives by industry in the future.

Phenoxyethanol, or 2-phenoxyethanol, has a large spectrum of antimicrobial activity and has been widely used as a preservative in cosmetic products for decades. It is effective against various Gram-negative and Gram-positive bacteria, as well as against yeasts, and has only a weak inhibitory effect on resident skin flora. According to the European Scientific Committee on Consumer Safety, phenoxyethanol is safe for all consumers - including children of all ages - when used as a preservative in cosmetic products at a maximum concentration of 1%. Adverse systemic effects have been observed in toxicological studies on animals but only when the levels of exposure were many magnitudes higher (around 200-fold higher) than those to which consumers are exposed when using phenoxyethanol-containing cosmetic products. Despite its widespread use in cosmetic products, phenoxyethanol is a rare sensitizer. It can be considered as one of the most well-tolerated preservatives used in cosmetic products.

In this chapter, we examine the synthesis of phenolic compounds via catalytic reactions and processes, with a special focus on sustainability issues. In recent years, considerable steps forward have been made with the aim of developing greener routes for the functionalisation of phenol and diphenols. Examples of these include: (a) the use of methanol instead of methylchloride or dimethylsulphate for the synthesis of ethers, such as anisole, guaiacol and veratrol, which are key intermediates for the synthesis of a plethora of fine chemicals and specialties; (b) the use of alkylcarbonates for the synthesis of alcohol-ethers (e.g. phenoxyethanol), cresols, and ethers; and (c) the use of aldehydes instead of halogenated alkanes for the hydroxyalkylation of phenolics to alcohols, such as piperonyl alcohol. Indeed, many of these reactions were inspired by the successful industrial application of methanol as an electrophile for the synthesis of o-cresol and 2,6-xylenol. The latter reaction may be considered the very first ‘green’ process for the functionalisation of phenol; surprisingly, despite its industrial use for several decades, only in recent years has the mechanism of this reaction been elucidated. Some emblematic examples of the more sustainable synthesis of phenolic compounds, briefly discussed here, are 2,6-xylenol, guaiacol, vanillin, methylendioxobenzene, phenoxyethanol, hydroxytyrosol and piperonal.

TEZ12271 Tez (Yüksek Lisans) -- Çukurova Üniversitesi, Adana, 2019. Kaynakça (s. 35-42) var. IX, 43 s. :_tablo ;_29 cm. Bu çalışmada fenoksietanolün juvenil japon balığında (3.87 cm ve 4.05 g ) 30 dakika ve 15 saat süreli uygulamalarındaki optimal doz tespit edilmiştir. Ayrıca, japon balığının 1/4 su ve 3/4 oksijen basılmış naylon torbalarda 15 saat taşınmasında, fenoksietanol ve açlık süresinin balığın stok miktarına etkileri belirlenmiştir. Balıkların anesteziye giriş süresi doza bağlı olarak 3 ile 11 dakika, anesteziden çıkış süresi ise 5 ile 15 dakika arasında gerçekleşmiştir. Fenoksietanolün balık üzerindeki anestezik etkisi 100 ?l/L' dozdan itibaren başlamıştır. Derin anestezi için fenoksietanolün uygun dozları 30 dakika süre için 250 ?l/L, 15 saat süre için 200 ?l/L' dir. Balıkların naylon torbalarda taşınmasında 4 gün aç bırakılması 2 gün aç bırakılmasına göre daha yüksek bir stoklamaya olanak sağlamış (P0.05). Açlık süresi, anestezik uygulaması ve stoklama oranları arasında bir intereaksiyon bulunamamıştır (P>0.05). Fenoksietanol kullanmaksızın 4 gün aç bırakılan japon balıklarının oksijen basılmış naylon torbalarda 40, 60 ve 80 adet/L stoklama koşullarında % 100, 98.33 ve 91.87 yaşama oranı tespit edilmiştir. Birim hacimde taşınacak balık sayısı ve yaşama oranı birlikte ele alındığında, juvenil japon balıkları için optimal stoklama oranı litreye 60 adet balık uygun gözükmektedir. In this study, the optimum dose of phenoxyethonol in juvenile goldfish (3.87cm and 4.05 g) between 30 minutes and 15 hours application was determined. In addition, the effects of phenoxyethanol and starvation time on the fish were determined in the transport of goldfish in 1/4 water and 3/4 oxygen compressed nylon bags for 15 hours. The anesthesia time of the fish was between 3 and 11 minutes depending on the dose and the exit time from the anesthesia was between 5 and 15 minutes. The anesthetic effect of phenoxyethanol on fish started from the dose of 100 ?l / L. Suitable doses of phenoxyethanol for deep anesthesia are 250 ?l / L for 30 minutes and 200 ?l / L for 15 hours. Starving the fish in nylon bags for 4 days provided a higher storage opportunity than fasting for 2 days (P 0.05). There was no interaction between starvation time, anesthetic administration and stocking rates (P> 0.05). 100%, 98.33 and 91.87% survival rates were determined in 40, 60 and 80 pcs / L stocking conditions of oxygen fished nylon bags which were starved for 4 days without using phenoxyethanol. When the number of fish to be transported in mass and survival rate are taken together, the optimal stocking rate for juvenile goldfish is 60 fish per liter. Bu çalışma Ç.Ü. Bilimsel Araştırma Projeleri Birimi tarafından desteklenmiştir. Proje No: SÜF2013YL5.