The occurrence and health risks of fluorescent whitening agents (FWAs) in bottled water were reported for the first time. FWA184 and FWA393 were the most frequently detected FWAs, with mean ...concentrations of 3.99–17.00 ng L−1. Phthalates (PAEs) such as dibutyl phthalate (DBP), di-iso-butyl phthalate (DiBP), and diethylhexyl phthalate (DEHP) were prevalent in bottled water, with mean levels of 40.89–716.66 ng L−1, and their concentrations in bottled water were much higher than those of FWAs. FWAs and PAEs in bottles and caps were extracted using organic solvent, and the correlation analysis showed that FWA393 and DEHP most likely originated from bottles, while bottle caps were the main sources of DBP and DiBP. The calculated risk quotients (RQs) of target substances and all age groups were considerably lower than the threshold of 0.1, indicating that consuming bottled water containing these plastic additives was unlikely to pose health risks for people of all ages. However, RQ values for underage people were several times higher than those for adults and hence cannot be neglected; therefore, special attention should be paid to understand the potential risks posed by the exposure to these plastic additives during early life stages, especially the infant stage.
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•Fluorescent whitening agents (FWAs) were ubiquitous but at trace level (< 10 ng L-1).•Phthalates’ concentrations (up to 1.2 μg L-1) were much higher than those of FWAs.•Plastic bottles and bottle caps were the main source of these plastic additives.•Early life stages exhibited 3–5 times higher risk quotient values than adulthood.
Fluorescent whitening agents (FWAs) are very important chemical additives that are widely applied in the industrial production field. The history of global FWA production and use spans more than 60 ...years, but the environmental fate of FWAs has been less reported in the public literature and most studies predate 2000; in addition, the studied FWAs were still limited to FWA71 and FWA351. In this study, the occurrence and distribution of 9 commonly used FWAs in a lake in North China were reported for the first time. We found that 6 target FWAs were prevalent in the lake, and the concentration levels were usually at the ng L−1 level. Decreasing FWA levels with increasing distance from the estuary area were observed in summer. FWA135, FWA185, and FWA367, the most detected 3 FWAs, with the ecological risk at high levels, and ΣRQ >10 were obtained from all the investigated samples, suggesting that all the sampling sites could be considered with certain ecological risk for aquatic life. As a category of heavily and widely used dyes, FWAs in environmental media have been ignored for a long time. Substantial additional research needs to be conducted to determine the environmental behavior and ecological toxicology of FWAs.
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•Nine Fluorescent Whitening Agents (FWAs) in China were reported for the first time.•Most target FWAs were ubiquitous in water samples but at trace levels (<10 μg L−1).•Decreasing FWA levels with increasing distance from the estuary area were observed.•All the sampling sites were considered with certain ecological risk for aquatic life.
A COMPLETE, UP-TO-DATE RESOURCE OF INFORMATION ON MORE THAN 150 FLUORESCENT DYES AND PROBES Handbook of Fluorescent Dyes and Probes is the most comprehensive volume available on the subject, covering ...all the available dyes and probes known to date in the literature for uses in various fields. Top dye expert Dr. Ram Sabnis organizes the compounds alphabetically by the most commonly used chemical name. He presents an easy-to-use reference complete with novel ideas for breakthrough research in medical, biological, chemical, color, material, physical and related allied fields. The ease of use of the handbook is further enhanced by various appendixes provided at the end of the book to conveniently and easily locate the dye as per the reader's need. This is the first book to give the CAS registry numbers, chemical structure, Chemical Abstract (CA) index name, all other chemical names, Merck Index number, chemical/dye class, molecular formula, molecular weight, physical form, solubility, melting point, boiling point, pKa, absorption maxima, emission maxima, molar extinction coefficient, and quantum yield of fluorescent dyes and probes, as well as to provide access to synthetic procedures (lab scale and industrial scale) of dyes and probes in a single source. This user-friendly handbook also features references on safety, toxicity and adverse effects of dyes and probes on humans, animals and the environment, including: acute/chronic toxicity aquatic toxicity carcinogenicity cytotoxicity ecotoxicity genotoxocity hematotoxicity hepatotoxicity immunotoxicity marine toxicity microbial toxicity mutagenicity nephrotoxicity neurotoxicity nucleic acid damage oral toxicity phototoxicity phytotoxicity reproductive toxicity skin toxicity Containing imaging/labeling applications, biological/medical applications and industrial applications, Handbook of Fluorescent Dyes and Probes is a convenient, vital resource for industrial and academic researchers, and a valuable desktop reference for medical professionals, lab supervisors, scientists, chemists, biologists, engineers, physicists, intellectual property professionals, students, and professors. * Includes all fluorescent dyes & probes known to date and provides a complete, up-to-date library of information in onereference/handbook * Includes more than 300 fluorescent dyes & probes organized alphabetically by the commonly used Chemical Name * Provides access to synthesis procedures (lab scale and industrial scale) of fluorescent dyes & probes * First book to provide references on safety, toxicity and adverse effects of fluorescent dyes and probes on humans, animals, and the environment * User-friendly and convenient resource guide for chemical, biological, medical, and intellectual property professionals in a broad range of disciplines
This study explores the quenching of the dianionic fluorescent whitening agent, NFW, by various substances, including methyl viologen (MV), in water and in the presence of beta-cyclodextrin ...(beta-CD). Results of a fluorescence spectroscopic examination of the beta-CD-NFW system are presented. It was found that NFW forms a 1:1 inclusion complex with beta-CD with an association constant of 2540 + or - 380 M.sup.-1. The included NFW fluorescent state is protected by the beta-CD cavity from a range of water-based quenchers (neutral, anionic, and cationic). Quenching proceeds near the diffusion-controlled limit in water for the quenchers tested with the exception of the dicationic MV. Methyl viologen is an extremely efficient quencher of NFW fluorescence with a nominal K.sub.SV ~ 5.0 * 10.sup.3 M.sup.-1 in water alone, corresponding to a nominal k.sub.q of ~ 4 * 10.sup.12 M.sup.-1 s.sup.-1, which exceeds the diffusion-controlled limit in this solvent. The quenching efficiency of MV is strongly suppressed in the presence of 10 mM beta-CD (K.sub.SV = 105 + or - 12 M.sup.-1) and in the presence of NaCl (K.sub.SV = 106 + or - 9 M.sup.-1 at 0.5 M salt). In the absence of CD or salt, there is a strong contribution from static quenching in the MV system; the presence of these additives suppresses the static quenching. Various results suggest the static quenching is due to formation of a ground-state complex between the dianion NFW and the dication MV.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Daylight fluorescent pigments are complex artists' colorants made of multiple admixed dyes and additives infused in a polymer resin. Their unique photochemistry creates interesting optical effects ...that make them appealing for a range of applications. The wavelength dependence of the dyes' emissive properties has also led to their use in works meant to be displayed under nontraditional high energy light sources, such as blacklights. The intended display methods and the photochemistry of the constituent dyes can lead to chemical instability and also pose unique challenges for conservation and exhibition. In Part 1 of this research, we reported on the chemical constituents of colorants from two major manufacturers. In this paper, we provide a comprehensive report of the spectral properties and lightfastness of paints prepared with the pigments. The optical properties and chemical stability of these colorants are correlated with the composition. Variation in composition can lead to unique markers that could be useful for conservation treatment and exhibition considerations. Changes in the dyes used in the pigment formulation over time are considered in the comparison of two objects: a Stephen Sprouse silvered leather motorcycle jacket featuring fluorescent art by Stefano Castronovo and selections from the Day-Glo Designer's Guide from 1969.
Optical brighteners (OBs) have become an integral part of our daily lives and culture, with a growing number of applications in various fields. Most industrially produced OBs are derived from ...stilbene, which has been found in environmental matrices. The main objectives for this work are as follows: first, to identify protein targets for DAST, FB-28, and FB-71, and second, to assess their effects in some behaviors physiologic of Caenorhabditis elegans. To achieve the first objective, each OB was tested against a total of 844 human proteins through molecular docking using AutoDock Vina, and affinities were employed as the main criteria to identify potential target proteins for the OB. Molecular dynamics simulations took and validated the best 25 docking results from two protein databases. The highest affinity was obtained for the Hsp70-1/DAST, CD40 ligand/FB-71, and CD40 ligand/FB-28 complexes. The possible toxic effects that OBs could cause were evaluated using the nematode C. elegans. The lethality, body length, locomotion, and reproduction were investigated in larval stage L1 or L4 of the wild-type strain N2. In addition, transgenic green fluorescent protein (GFP) strains were employed to estimate changes in relative gene expression. The effects on the inhibition of growth, locomotion, and reproduction of C. elegans nematodes exposed to DAST, FB-71, and FB-28 OBs were more noticeable with respect to lethality. Moreover, an interesting aspect in OB was increased the expression of gpx-4 and sod-4 genes associated with oxidative stress indicating a toxic response related to the generation of reactive oxygen species (ROS). In all cases, a clear concentration-response relationship was observed. It is of special attention that the use of OBs is increasing, and their different sources, such as detergents, textiles, plastics, and paper products, must also be investigated to characterize the primary emissions of OBs to the environment and to develop an adequate regulatory framework.
Oxyresveratrol (ORV) is naturally found in Artocapus lakoocha Roxb. (AL), similar to resveratrol. This AL extract has demonstrated considerable importance in dietary supplements and cosmetics for its ...anti-tyrosinase and antioxidant properties. There is a great demand for ORV in the cosmetic and pharmaceutical industries. Traditionally, harsh solvents have been used to extract ORV from AL. This study aims to address this issue by introducing green technology with a ready-to-use extract for the enrichment of ORV extraction from AL using deep eutectic solvents (DESs). Thirty-three DESs were synthesized and characterized. The extraction efficiency of these DESs was evaluated by ORV content (g ORV/kg dried plant) and compared with the conventional solvents, analyzed by validated HPLC. Notably, two synthesized DESs, namely choline chloride/citric acid/water (2:1:3) (DES10) and choline chloride/xylose (1:1) (DES17), showed higher ORV content than the conventional solvents and were therefore selected for optimization of extraction conditions using Box–Behnken designs, considering three variable levels: time, temperature, and water as co-solvents. Interestingly, the biological activities of ORV-enriched extracts from DES10 and DES17 were evaluated, and the results showed that they were 74-fold and 252-fold more potent than kojic acid in terms of tyrosinase inhibitory activity. DES17 was 17-fold more potent antioxidants than ascorbic acid. The morphology of AL powder before and after extraction with DESs under SEM suggested that DESs have the same mechanism as classical organic solvents. These ORV-enriched extracts can be directly incorporated into cosmetic formulations and production scales without the need to prepare a stock solution and are therefore referred to as ready-to-use extracts. This study successfully pioneered the use of DESs for environmentally friendly and highly efficient ORV extraction from AL to produce ready-to-use extracts and applications for the pharmaceutical and cosmetic industries.
This study describes a novel approach for the simultaneous determination of CBS-X and CXT as widely used optical brighteners in household detergent, by combining the advantage of the high sensitivity ...of molecular fluorescence, and the selectivity of second-order chemometric methods. The proposed method is assisted by second-order chemometric analyses employing the PARAFAC, SWATLD and APTLD that help us to determine CBS-X and CXT in laundry powders and environmental samples, through the unique decomposition of the three-way data array. Proposed method can provide the extraction of relative concentrations of the analytes, as well as the spectral profiles. This approach achieves the second-order advantage and in principle could be able to overcome the spectral uncalibrated interference problems in the determination of CBS-X and CXT at the ng g−1 level.
By spiking the known concentrations of these compounds to the real samples, the accuracy of the proposed methods was validated and recoveries of the spiked values were calculated. High recoveries (90.00%–113.33%) for the spiked laundry powders and real environmental samples indicate the present method successfully faces this complex challenge without the necessity of applying separation and preconcentration steps in environmental contaminations.
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•Simultaneous determination of CBS-X and CXT in the laundry powders and environmental samples•Handling the direct interfering effect of a complex matrix by modeling system in the presence of uncalibrated interference•Discriminating between CBS-X and CXT by employing trilinear second-order calibration•Unique decomposition of the three-way data array by PARAFAC, SWATLD and APTLD
Rural river catchments are impacted by diffuse pollution sources from agricultural practices and on-site domestic wastewater treatment systems (DWWTS), mainly septic tanks. Methods that can ...distinguish between contamination sources will significantly increase water management efficiency as they will allow for the development and application of targeted remediation measures. Fluorescent whitening compounds (FWC), are used as optical brighteners in laundry detergents and enter the environment through the discharge of domestic wastewater effluents. Due to their human specific source and potential simple fluorometric measurement this represents a very attractive method to be used by state monitoring agencies.
In this study the suitability of FWCs as chemical indicators for human faecal contamination has been investigated in rural Irish catchments. It was found that no quantitative measurements are possible for FWCs in natural waters when using simple fluorometric methods. Hence a simple presence/absence approach needs to be applied. The detectability of FWCs was quantified and found to decrease with higher organic matter content of the river water which has its own fluorescence. This enabled the establishment of equations to predict detection limits and assess the method's suitability for individual catchments based on organic matter concentrations. Furthermore a modified photodecay method is suggested that increases sensitivity of the technique by up to 59%. Applications at rural study sites found some removal of FWCs in percolation areas of DWWTSs but they were still detectable 40 cm below the infiltration depth. FWCs were also detected as distinguishable peaks in impacted streams where septic tank effluents have a high contribution to the river flow.
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•The fluorometric FWC detection is only possible with a presence/absence approach.•The sensitivity of an existing photodecay method has been improved by up to 59%.•Detection limits for FWCs increase with NOM content of water samples.•An approach is presented to assess the method's suitability on a catchment basis.•The FWC detectability in streams and rivers increases during low flow conditions.