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This review examines the environmental occurrence and fate of aromatic amines (AAs), a group of environmental contaminants with possible carcinogenic and mutagenic effects. AAs are known to be partially responsible for the genotoxic traits of industrial wastewater (WW), and AA antioxidants are acutely toxic to some aquatic organisms. Still, there are gaps in the available data on sources, occurrence, transport, and fate in domestic WW and indoor environments, which complicate the prevention of adverse effects in aquatic ecosystems. We review key domestic sources of these compounds, including cigarette smoke and grilled protein-rich foods, and their presence indoors and in aquatic matrices. This provides a basis to evaluate the importance of nonindustrial sources to the overall environmental burden of AAs. Appropriate sampling techniques for AAs are described, including copper-phthalocyanine trisulfonate materials, XAD resins in solid-phase extraction, and solid-phase microextraction methods, which can offer insights into AA sources, transport, and fate. Further discussion is provided on potential progress in the research of AAs and their behavior in an aim to support the development of a more comprehensive understanding of their effects and potential environmental risks.

A core-shell amino-functionalized glycidyl methacrylate magnetic molecularly imprinted polymer (MIP) was synthesized by the suspension polymerization/surface imprinting method and characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), mercury porosimetry, nitrogen gas adsorption–desorption, and elemental analysis. This MIP was used as the sorbent in dispersive solid-phase microextraction (DSPME) of aniline from textile wastewater prior to high-performance liquid chromatography-mass spectrometry (HPLC-MS) measurements. Since aniline is toxic and a probable human carcinogen, its determination in water is of great significance. This is a challenging task because aniline is usually present at trace levels. The effects of different DSPME variables on the preconcentration efficiency have been studied by using the Plackett–Burman screening design of experiments (DoE) followed by response surface methodology optimization using the Box-Behnken design. Thus, DoE enabled the investigation of several variables simultaneously. Under optimized conditions, aniline was effectively and selectively separated by a small amount of the DSPME sorbent and detected in real textile wastewater samples. The method detection limit of 1 ng mL−1 was attained, with good method linearity and acceptable recovery and precision. The results showed that the studied MIP could be a reliable DSPME sorbent for efficiently analyzing trace aniline in real wastewater samples.

Aromatic compounds such as aromatic amines (AAs) or lignocellulose biomass derivatives are often recalcitrant to biological processes (i.e., anaerobic digestion). The level of recalcitrance is usually explained by the biochemical structure of the compounds, which determines their removal. AAs are present in dye wastewaters mainly originated from textile industries and are considered carcinogenic and challenging pollutants to be removed from wastewater. The hydrolysis of lignin leads to the formation of some aromatic compounds, which could be recalcitrant at certain concentrations and operation conditions. Similarly, derivatives from sugar degradation such as furfurals and 5-hydroxymethylfurfural (HMF) from pentose and hexose degradation, respectively, have also been reported to be recalcitrant to anaerobic treatment. This chapter details the different forms of recalcitrance found and/or formed during wastewater and organic solid waste treatment, particularly in the anaerobic digestion process. Moreover, the possible strategies to mitigate the recalcitrance of these compounds are comprehensively explained., Green Open Access added to TU Delft Institutional Repository 'You share, we take care!' - Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public., Sanitary Engineering

Recycled crumb rubber (CR) is rich in compounds with unrecognized toxic potency; this study aims at the development of an analytical method that would allow identification and quantification of a very wide range of organic compounds extractable from the complex rubber matrix. The analytical set-up includes target analysis of polycyclic aromatic hydrocarbons (PAHs) and methyl-PAHs and suspect screening of raw extracts to tentatively identify primary organic compounds present, but not included in the standard target analysis of recycled rubber, followed by analytical method development and target analysis of identified compounds. Analyzed samples included weathered and new CR originating from football turf granulates, rubber mats, and end-of-life car tires (ELTs). The developed analytical method involves sonication extraction, followed by solid phase extraction (SPE) fractionation that enables simple and efficient separation of analytes with broad polarity scale. The application of SPE fractionation resolves coelution problems and simplifies the chromatograms. This analytical approach allowed to identify and quantify 46 sample specific compounds, including several heterocyclic PAHs like 2-methylthiobenzothiazole, benzonapthothiophenes, benzonaphthofuranes and aromatic amines like diphenylamine and N-phenyl-2-naphthylamine, which to our knowledge were not determined before. The PAHs concentrations determined in CR tiles purchased in Dutch and Spanish shops exceed the EU limits for articles marketed for use by the public. Furthermore, sets of methylated PAHs, dibenzothiazoles and aromatic amines were identified and quantified, and several other compounds were tentatively identified. The obtained results stress the need for expanding the list of target compounds analyzed in CR and the need for longitudinal studies on weathering processes taking place in CR

The aminoimidazoazaarenes types of heterocyclic amines (AIA-types of HCAs) and the 4PAH of polycyclic aromatic hydrocarbons (PAHs) are chemical compounds that form abundantly in muscle meat cooked at 150°C and above from the reaction between the amino acids and the reducing sugar. Studies on HCAs and PAHs formation are essential as both compounds have been classified as carcinogenic by the International Agency for Research on Cancer (IARC). Many studies on HCAs and PAHs focused on their formation in food samples. However, the most susceptible amino acid and sugar precursor was unable to be identified due to the complex system containing many food components. Chemical model system have the advantages of allowing researchers to study the effect of single precursor on HCAs or PAHs formation as the system contains only the precursor. From using chemical model system, previous studies have identified phenylalanine, proline, and glycine as the amino acids responsible for the formation of the AIA-types of HCAs and the 4PAH that are abundant in cooked muscle meat. Nevertheless, studies on the simultaneous formation are limited although they originated from the same precursor and most reported studies focused on HCAs and PAHs formation separately. There is also limited data on the rate formation involving kinetic studies that can be used to signify the difference between each precursor on the formation of HCAs and PAHs. Therefore, the objective of this study is to identify the most susceptible amino acid (phenylalanine, proline, and glycine) and sugar (glucose, fructose, and sucrose) precursor for the simultaneous formation of HCAs and PAHs at household cooking time and temperature using chemical model system with the adaption of kinetic study. Essentially, this study uses an amino acid model system and a sugar model system to investigate the effects of these precursors on the simultaneous formation of HCAs and PAHs. The used of phenylalanine, proline, and glycine were selec

Nowadays, people are increasingly exposed to various carcinogenic factors. The problem of carcinogenic effects is relevant, since with the development of modern sciences a detailed study of the problem, the action of pathogenic factors, mechanisms and, most importantly, methods of dealing with this problem are possible., В настоящее время люди все чаще подвергаются воздействию различных канцерогенных факторов. Проблема канцерогенного воздействия является актуальной, так как с развитием современных наук возможно детальное изучение проблемы, действия патогенных факторов, механизмов и самое главное – методов борьбы с данной проблемой.

© 2019 Elsevier Inc. Nowadays, most of the swimsuits are mainly made of artificial fibres, which have interesting properties such as water repellence and fast drying. Swimsuits contain a wide range of additives, which can mean a hazard for the environment and/or human health. In this study, the concentrations of formaldehyde (free and water soluble), 24 aromatic amines, and 28 trace elements (Ag, Al, As, B, Ba, Be, Bi, Cd, Co, Cr, Cu, Fe, Hg, Mg, Mn, Mo, Ni, Pb, Sb, Sc, Se, Sm, Sr, Sn, Tl, Ti, V and Zn) were analysed in 39 swimsuits covering a wide range of materials, colours and brands. Dermal exposure and health risks were assessed for adults (men and women) aged > 18 years old, babies between 2 and < 3 years old, children (boys and girls) between 3 and < 6 years old and 6 and < 11 years old, and teenagers (boys and girls) between 11 and < 16 years old, wearing swimsuits for 4 h or 8 h. Formaldehyde and aromatic amines were below their respective detection limits in all samples (<16 and < 1.5 mg/kg, respectively). Regarding trace elements, Ti showed the highest mean levels (1844 mg/kg), being significantly higher in polyamide (3759 mg/kg) than in polyester (24.1 mg/kg) swimsuits. These high Ti levels were confirmed by environmental scanning electron microscope in a single sample made of polyamide. Increased concentrations of Cr were also observed, but only in polyamide black fabrics, with values ranging from 624 to 932 mg/kg. Non-cancer risks (hazard quotients) derived from the exposure to trace elements were in a safe zone for all analysed trace elements. Furthermore, the carcinogenic risks were evaluated for As, Cr and Pb, exhibiting values below the 10−5 threshold, with the exception of Cr in babies and children-girls. For Ti, health risks could not be calculated d

Urothelial carcinoma of the bladder is one of the most common malignancies in the industrialized world, mainly caused by smoking and occupational exposure to chemicals. The favorable prognosis of early stage bladder cancer underscores the importance of early detection for the treatment of this disease. The high recurrence rate of this malignancy also highlights the need for close post-diagnosis monitoring of bladder cancer patients. As for other malignancies, aberrant DNA methylation has been shown to play a crucial role in the initiation and progression of bladder cancer, and thus holds great promise as a diagnostic and prognostic biological marker. Here, we describe a protocol for a versatile DNA methylation enrichment method, the Methylated CpG Island Recovery Assay (MIRA), which enables analysis of the DNA methylation status in individual genes or across the entire genome. MIRA is based on the ability of the methyl-binding domain (MBD) proteins, the MBD2B/MBD3L1 complex, to specifically bind methylated CpG dinucleotides. This easy-to-perform method can be used to analyze the methylome of bladder cancer or urothelial cells shed in the urine to elucidate the evolution of bladder carcinogenesis and/or identify epigenetic signatures of chemicals known to cause this malignancy.

The occurrence of mutagenicity in primary aromatic amines has been investigated using conformal prediction. The results of the investigation show that it is possible to develop mathematically proven valid models using conformal prediction and that the existence of uncertain classes of prediction, such as both (both classes assigned to a compound) and empty (no class assigned to a compound), provides the user with additional information on how to use, further develop, and possibly improve future models. The study also indicates that the use of different sets of fingerprints results in models, for which the ability to discriminate varies with respect to the set level of acceptable errors.

Salicylic acid was used as an efficient catalyst for the diastereoselective synthesis of dispirohydroquinoline-bis (Meldrim’s acid) derivatives via a one-pot domino eight-component reaction of arylamines, aromatic aldehydes and Meldrum’s acid in CH3CN at room temperature. The remarkable advantages offered by this method are inexpensive catalyst, good yields, simple and easy work-up procedure. The characterization of products was done by IR, mass, 1H NMR, 13C NMR spectroscopy, and elemental analyses. The stereoselectivity of compounds was confirmed with crystallography and NMR spectroscopy.

A significant acceleration in the hydrodeamination of in situ formed diazonium salts (from aromatic amines) has been observed in the presence of 10-mol% salicylic acid, using tetrahydrofuran as the hydrogen donor. The reaction proceeds efficiently at 20 °C for a wide range of substituted anilines, even at 10-mmol scale, without any other additive. The same protocol has been adapted to the selective deuterodeamination of some aromatic amines. Control experiments clearly show that aryl radicals are involved in the reaction mechanism.

Heterocyclic aromatic amines (HCAs) are an important group of food mutagens and potential carcinogens which are formed during heat processing. Phenolic compounds, ubiquitous in plants are well known for their free radical scavenging activities which can inhibit the formation of HCAs. There is no study which have investigated the effects of different proportions of spices/herbs on the reduction of HCAs in grilled beef. This research has been conducted to determine the antioxidant property of selected herbs and spices, optimize the proportion of their combination to achieve the highest reduction of HCAs, identify the main bioactive inhibitors of HCAs formation and explore the level of mutagenicity and toxicity of marinated grilled beef. Selected herbs and spices (turmeric, curry leaf, lemon grass and torch ginger) were evaluated for their total phenolic compound (TPC), total phenolic content (TFC), DPPH radical scavenging activity and ferric reducing antioxidant power (FRAP). The bioactive compounds of the samples were identified using high performance liquid chromatography (HPLC). Nineteen combinations of selected herbs and spices (turmeric, curry leaf, lemon grass and torch ginger) based on a simplex centroid mixture design were used to marinate beef in order to determine the optimal proportion which achieve the highest reduction of HCAs. The results showed that the combination of turmeric and lemon grass exhibited the highest reduction of HCAs. The optimum mixture of crude extract of these herbs was fractionated to determine the main inhibitors of PhIP formation. Six fractions were collected and applied into PhIP model system containing glucose, phenylalanine and creatinine. Liquid chromatography-mass spectrometry quadruple time of flight (LC-MS/MS Q-TOF) and orthogonal partial least-squares (OPLS) analysis was used to correlate PhIP reduction to different metabolite profiles of each fraction. In vivo and in vitro experiments were respectively carried out using zeb

Catalytic ring-opening of bio-sourced non-strained lactones with aromatic amines can offer a straightforward, 100% atom-economical, and sustainable pathway towards relevant N-aryl amide scaffolds. Herein, the first general, metal-free, and highly efficient N-aryl amide formation is reported from poorly reactive aromatic amines and non-strained lactones under mild operating conditions using an organic bicyclic guanidine catalyst. This protocol has high application potential as exemplified by the formal syntheses of drug-relevant molecules.

A simple method for simultaneous determination of twenty-one analytes, belonging to two classes of compounds, aromatic amines and quinolines, is presented. Several of the analytes considered in this study frequently occur in textiles goods on the open market and have been related to allergic contact dermatitis and/or are proven or suspected carcinogens. The method includes an efficient clean-up step using graphitized carbon black (GCB) that simplifies and improves the robustness of the subsequent GC-MS analysis. Briefly, after solvent extraction of the textile sample, the extract is passed through a GCB SPE cartridge that selectively retain dyes and other interfering compounds present in the matrix, producing a clean extract, suitable for GC-MS analysis, is obtained. The method was evaluated by spiking blank textiles with the selected analytes. Method quantification limits (MQL) ranged from 5 to 720 ng/g depending on the analyte. The linear range of the calibration curves ranged over two order magnitude with coefficients of determination (R-2) higher than 0.99. Recoveries ranged from 70 to 92% with RSDs 1.7-14%. The effectiveness of the method was tested on a variety of textile materials samples from different origin. In a pilot explorative survey, 2,6-dichloro-4-nitroaniline was detected in all the analysed clothing samples in concentrations ranging from 1.0 to 576 mu g/g 2,4-dinitroaniline was detected in four of the seven samples with a highest concentration of 305 mu g/g Quinoline was detected in all samples in concentrations ranging from 0.06 to 6.2 mu g/g. (C) 2016 Elsevier B.V. All rights reserved.

The presence of aromatic amines in the environment has been in the focus of research, as many of these compounds are known or suspected mutagens and carcinogens. To facilitate the detection of aromatic amines in complex environmental samples by LC-high resolution mass spectrometry, an on-line-post-column and a pre-column derivatization method to label (in an ideal case) all aromatic amines was evaluated by applying different derivatization reagents. 4-Fluoro-7-nitro-2,1,3-benzoxadiazole (NBD-F) was found to be the most promising labeling reagent due to its high reactivity with both primary and secondary amines and its low signal in positive mode electrospray ionization (ESI+). Post-column on-line derivatization did not result in sufficient signal intensities of derivatives. With pre-column derivatization most of the selected aromatic amines resulted in a derivative that shows common fragments of diagnostic value. The selectivity of NBD-F was studied in depth with a data set of 220 compounds with different functional groups showing that also aliphatic amines and some thiols yield a derivative. The developed method was successfully applied to wastewater effluent samples and several derivatives were confirmed by diagnostic neutral losses.

Insensitive munition compounds (IMC) are an emerging class of explosives that are less susceptible to accidental explosions compared to the conventional explosives they will be replacing. An IMC that has been incorporated in several explosives formulations is 2,4-dinitroanisole (DNAN). As the manufacture, storage, and use of these compounds increases, the expected releases in natural and engineered systems might pose an environmental hazard to public health and ecosystems. To date there is little information on the environmental fate and toxicology of DNAN. However, nitroaromatic compounds are known to be toxic, mutagenic and difficult to completely biodegrade. In order to study the fate and (bio)transformation of DNAN, microcosm studies with soils and anaerobic wastewater sludge were performed to determine (bio)transformation pathways and key factors influencing (bio)conversion. Transformation was enhanced in anaerobic conditions, in particular when exogenous electron donor was added. Abiotic transformation (in heat-killed soil) was also significant and dominated transformation reactions in soils that were not amended with exogenous electron donor. The organic carbon content of soils was a key factor that correlated to the anaerobic biotransformation rate. Having identified (bio)transformation products using liquid chromatography coupled to quadrupole time-of-flight mass spectrometry, an overall pathway of (bio)transformation was devised and consistent with nitro-group reduction to form aromatic amines. During the nitro-group reduction, reactive products (e.g. nitroso-intermediates) coupled with amines to form azo-dimers and oligomers. Subsequent transformation pathways included N-alkylation, N-acetylation, and stepwise demethoxylation of these oligomers. The assessment of the toxicity of DNAN and its (bio)transformation products was performed utilizing microbial toxicity assays and ecotoxicity evaluation with zebrafish (Danio rerio) embryos. Overall DNAN severely

Quaternary ammonium-functionalized silica materials were synthesized and applied for solid-phase extraction (SPE) of aromatic amines, which are classified as priority pollutants by US Environmental Protection Agency. Hexamethylenetetramine used for silica surface modification for the first time was employed as SPE sorbent under normal phase conditions. Hexaminium-functionalized silica demonstrated excellent extraction efficiencies for o-toluidine, 4-ethylaniline and quinoline (recoveries 101-107%), while for N,N-dimethylaniline and N-isopropylaniline recoveries were from low to moderate (14-46%). In addition, the suitability of 1-alkyl-3-(propyl-3-sulfonate) imidazolium-functionalized silica as SPE sorbent was tested under normal phase conditions. The recoveries achieved for the five aromatic amines ranged from 89 to 99%. The stability of the sorbent was evaluated during and after 150 extractions. Coefficients of variation between 4.5 and 10.2% proved a high stability of the synthesized sorbent. Elution was carried out using acetonitrile in the case of hexaminium-functionalized silica and water for 1-alkyl-3-(propyl-3-sulfonate) imidazolium-functionalized silica sorbent.After the extraction the analytes were separated and detected by liquid chromatography ultraviolet detection (LC-UV). The retention mechanism of the materials was primarily based on polar hydrogen bonding and π-π interactions. Comparison made with activated silica provedthe quaternary ammonium-functionalized materials to offer different selectivity and better extraction efficiencies for aromatic amines. Finally, 1-alkyl-3-(propyl-3-sulfonate) imidazolium-functionalized silica sorbent was successfully tested for the extraction of wastewater and soil samples.

Isocyanates, aromatic-, aliphatic- and alkanolamines are commonly used in the industry today. Millions of workers in Europe are exposed. The most frequent health symptoms are respiratory and dermal disorder. Due to the health risk most of the compounds in this thesis are regulated by authorities and have occupational exposure limits (OELs). Consequently, reliable and robust air sampling methods are urgently needed. In this thesis dry samplers for isocyanates, aliphatic- and alkanolamines have been developed and evaluated. The isocyanate sampler is now a commercial product (ASSET EZ4-NCP Dry Sampler, Supelco). The samplers were based on a denuder with a filter in series. The denuder and filter were impregnated with di-n-butylamine for the isocyanate sampler and with sulphuric acid for the aliphatic- and alkanolamine sampler. The robustness of the dry samplers was extensively evaluated. This was performed in a climate chamber containing a controlled atmosphere of the studied compounds. New methods based on hydrophilic interaction liquid chromatography (HILIC) coupled with tandem mass spectrometry (MSMS) were developed for determination of aromatic-, aliphatic- and alkanolamines in aqueous solutions. Isocyanates were determined by reversed-phase liquid chromatography MSMS. HILIC in combination with MS is a most powerful system, and highly sensitive determinations, several orders of magnitude below the OELs, of polar compounds present in the work environment can be accomplished. The selected samplers enable sampling during short sampling times and for whole work shifts. The samplers can be stored for months before and after sampling. The performance of the samplers was unaffected by variation in temperature, humidity, flow-rate and pre- and post-sampling of ambient air. Sampling for the compounds studied is now greatly simplified, and assessment of the work environment is facilitated., At the time of the doctoral defence the following papers were unpublished and had a status as follows: Paper 1: Epub ahead of print; Papers 3-5: Manuscripts

A ring-ring transformation in the series of spiro[indole-3,5′- pyrimido[4,5-b]quinoline]-2,2′,4′-trione derivatives prepared by a three-component reaction of (thio)barbituric acids, electron-rich aromatic amines, and isatins was observed. © Georg Thieme Verlag Stuttgart - New York.

This paper describes a simultaneously performed two-/three-phase hollow-fiber-based liquid-phase microextraction (HF-LPME) method for the determination of aromatic amines with a wide range of pKa (-4.25 to 4.6) and log KOW (0.9-2.8) values in environmental water samples. Analytes including aniline, 4-nitroaniline, 2,4-dinitroaniline and dicloran were extracted from basic aqueous samples (donor phase, DP) into the microliter volume of organic membrane phase impregnated into the pores of the polypropylene hollow fiber wall, then back extracted into the acidified aqueous solution (acceptor phase, AP) filling in the lumen of the hollow fiber. The mass transfer of the analytes from the donor phase through the organic membrane phase into acceptor phase was driven by both the counter-coupled transport of hydrogen ions and the pH gradient. Afterwards, the hollow fiber was eluted with 50 microL methanol to capture the analytes from both the organic membrane and the acceptor phase. Factors relevant to the enrichment factors (EFs) were investigated. Under the optimized condition (DP: 100 mL of 0.1 M NaOH with 2 M Na2SO4; organic phase: di-n-hexyl with 8% trioctylphosphine oxide (TOPO); AP: 10 microL of 8 M HCl; extraction time of 80 min), the obtained EFs were 405-2000, dynamic linear ranges were 5-200 microg/L (R>0.9976), and limits of detection were 0.5-1.5 microg/L. The presence of humic acid (0-25 mg/L dissolved organic carbon) had no significant effect on the extraction efficiency. The proposed procedure worked very well for real environmental water samples with microgram per liter level of analytes, and good spike recoveries (80-103%) were obtained., Sponsors:High-Tech Research and Development Program of China Grant(s): 2007AA06A407 2007AA06Z413 National Natural Science Foundation of China Grant(s): 20621703

The objectives of this study were to determine the effect of cooking method on HAs concentration of chicken and beef satay and the effect of marinating and different cooking conditions on HAs concentration of roasted chicken. Six common HAs were investigated: 2-amino-3-methylimidazo[4,5-f]quinoline (IQ), 2- amino 3,4-dimethylimidazo[4,5-f]quinoline (MeIQ), 2-amino-3,8-dimethylimidazo[ 4,5-f]quinoxaline (MeIQx), 2-amino-3,4,8-trimethylimidazo[4,5- f]quinoxaline (4,8-DiMeIQx), 2-amino-3,7,8-trimethylimidazo[4,5-f]quinoxaline (7,8-DiMeIQx), 2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP). Samples were extracted using 1M NaOH and ethyl acetate and clean up on solid phase extraction (SPE) column. The samples were then analysed using high performance liquid chromatography (HPLC) equipped with photodiode-array detector (DAD). Chicken and beef satay were grilled to two different degrees of doneness (medium and well done). Three types of cooking method were applied UPLOAD to both types of satay i.e. charcoal grilled (treatment A), microwave pretreatment prior to grilling (treatment B), and deep fried-microwave (treatment C). Both chicken and beef satay samples which undergone microwave pretreatment prior to grilling (treatment B) showed significantly (p<0.05) lower HAs concentration as compared to charcoal grilled satay (treatment A). Deep fried-microwave (treatment C) was applied to both types of satay as an alternative method to cook satay and was proven to produce lesser HAs as compared to treatments A and B in medium and well done cooked satay. HAs concentration were compared in marinated and unmarinated chicken before roasting. Three roasting conditions were applied to chicken i.e. 160°C for 120 min (treatment X), 180°C for 90 min (treatment Y) and 200°C for 60 min (treatment Z). The study showed that marinated chicken produced significantly (p<0.05) lower HAs concentration as compared to unmarinated chicken in all three different cooking treatments. Meanwhile, r

[EN] Mutagenicity is a toxicity endpoint associated with the chronic exposure to chemicals. Aromatic amines have considerable industrial and environmental importance due to their widespread use in industry and their mutagenic capacity. Biopartitioning micellar chromatography (BMC), a mode of micellar liquid chromatography that uses micellar mobile phases of Brij35 in adequate experimental conditions, has demonstrated to be useful in mimicking the drug partitioning process into biological systems. In this paper, the usefulness of BMC for predicting mutagenicity of aromatic amines is demonstrated. A multiple linear regression (MLR) model based on BMC retention data is proposed and compared with other ones reported in bibliography. The proposed model present better or similar descriptive and predictive capability.

Cooking fumes from commercial kitchens have long caused concern for those who live near them. Foodstuffs such as meat, fat, sugar, starch or oil can produce carbonaceous particles when cooked quickly at high temperatures. Carbonaceous particles discharged to the atmosphere can have significant environmental and health impacts, through lowering visibility and the health impact of fine particles on human beings. In this paper, we report a territorial-wide survey on the quantification of cooking fumes discharged from commercial kitchens of Chinese restaurants, Western restaurants and exotic food servicing areas. Results show that cooking fumes contain a wide spectrum of organic compounds including n-alkanes, polycyclic aromatic hydrocarbons (PAHs), fatty acids (FAs) and aromatic amines (AAs). It should be noted that commercial kitchens differ considerably in size, modes of operations, raw materials, cooking practices and air pollution control equipment. Our analytical results indicate that there is no statistically significant difference on the composition of their discharge in terms of carcinogenic elements such as PAHs, but at the 5\% significance level, the mean concentrations of n-alkanes at the discharge points of exotic food servicing areas are higher than at the discharges of Chinese or Western restaurants.

Experimental evidence has shown that a beverage containing Sunset Yellow FCF (labelled as E110 in the European Union), when exposed to natural conditions of summer temperature and sunlight, losses its colour. To possibly identify the degradation pathway and collect information on the potential toxicity of the uncoloured species formed, different degradation conditions, under both oxidising and reducing environments, were simulated in laboratory. Experiments were carried out under the following conditions: (i) thermally induced degradation, (ii) visible photo induced degradation, (iii) UV-photo induced conditions in oxidising environment (addition of hydrogen peroxide, Fenton reaction) and (iv) UV-photo induced conditions in reducing environment (addition of sulphide and ascorbic acid, addition of ascorbic acid in the absence and in the presence of saccharose). Decolourisation process was observed in oxidant conditions when applying the Fenton reaction but the reaction was too quick to be progressively followed. On the other hand, it was also possible to study the degradation reaction observed in reducing conditions in the presence of ascorbic acid. The HPLC-MS results gave evidence for the cleavage of the double bond and the protonation of the azo groups. The loss of colour is therefore not due to a mineralization process but to the formation of a dimeric form of 5-amino-6-hydroxy-2-naphthalene sulfonate and, likely, of p-amino- benzensulfonate.

Most explosives that occur as groundwater pollutants at DoD sites are nitro aromatic compounds (TNT, trinitrobenzene, and various di- and mono-nitrotoluenes) or nitramines (RDX, HMX, and Tetryl). Under favorable conditions, nitro aromatic compounds (NACs) react rapidly with zero-valent iron (Fe0), which suggests that permeable reactive barriers containing zerovalent iron (FePRBs) might be useful in the remediation of groundwater contaminated with explosives. Unfortunately, reduction of NACs by iron metal produces aromatic amines as the primary products, and these products are still substances of regulatory concern. As a result, fullscale implementation of FePRBs to treat explosives contaminated groundwater has been delayed until an effective treatment for the amines has been developed and tested. The goal of this project was to develop an oxidative treatment step to treat the products of nitro reduction, so that the combination would form a sequential reactive treatment zone (SRTZ) that could be used to reach treatment goals for TNT-contaminated groundwater under field conditions. To generate simulated effluent from an FePRB we prepared bench scale columns, packed initially with 100% construction-grade, granular iron metal. We found that 100% iron columns, even at flow rates as high as 125 ft/day, produced no TNT or degradation products. Some of the columns were operated for 1600 pore volumes with no TNT or any reaction products detected (by HPLC) in the effluent. The capacity of these columns to reduce TNT and sequester all of the reduction products suggested that simple FePRBs (with out the additional treatment zones associated with an SRTZ), might be sufficient for full-scale remediation of TNT-contaminated groundwater.

Published in Jnl. of Medicinal Chemistry, v33 n9 p2610- 2614 Sep 1990.

A 3-day workshop on the regulatory evaluation of petroleum hydrocarbons in dredged material was conducted 13-15 May 1986 at the US Army Engineer Waterways Experiment Station (WES), Vicksburg, Miss. The discussions culminated in the recommendation of specific hydrocarbon compounds and the development of a suggested tiered testing approach for regulatory evaluation of hydrocarbon-contaminated dredged material. The compounds selected were 15 priority pollutant polycyclic aromatic hydrocarbons: acenaphthene, acenaphthylene, anthracene, benz(a)anthracene, benzo(b)fluoranthene, benzo(k)fluoranthene, benzo(g,h,i)perylene, benzo(a)pyrene, chrysene, dibenz(a,h)anthracene, fluoranthene, fluorene, indeno(1,2,3-cd)pyrene, phenanthrene, and pyrene. The tiered testing approach consisted of first-tier acute toxicity tests and sediment analysis for the key hydrocarbons, followed by second-tier 10-day bioaccumulation tests. Other classes of hydrocarbons and biological tests were recommended for further research, with possible future inclusion in the evaluation scheme.

Small amounts of organic additives improve the quality of electrodeposited Cu by the substantial effect their adsorption at the cathode surface has on the kinetics of electron transfer, blocking active sites and electrostatic interaction as well as affecting bubble size/dynamics and hence the rate of diffusion-controlled metal deposition. The effects were investigated of eight aliphatic and aromatic amines on Cu electrodeposition from acid sulphate, using an insoluble Pb anode. Potentio-dynamic polarisation showed the limiting current and mass transfer coefficient to decrease with increasing concentration of amine derivatives. Adsorption of all amine inhibitors on the copper cathode obeyed Temkin, Flory-Huggin and kinetic adsorption isotherms. The values for free energy of adsorption were indicative of all of the amine inhibitors being strongly adsorbed on the copper surface, while tensiometric measurements showed that the amines reduced the surface tension of the solutions. At the end of the electrodeposition process, scanning electron microscopy (SEM) was employed to determine the influence of the amines on the surface morphology of the copper deposit. The addition of o-phenylenediamine to the copper bath had a strong influence on microstructure, resulting in a strongly adherent and uniform Cu deposit across the entire electrode surface., Small amounts of organic additives improve the quality of electrodeposited Cu by the substantial effect their adsorption at the cathode surface has on the kinetics of electron transfer, blocking active sites and electrostatic interaction as well as affecting bubble size/dynamics and hence the rate of diffusion-controlled metal deposition. The effects were investigated of eight aliphatic and aromatic amines on Cu electrodeposition from acid sulphate, using an insoluble Pb anode. Potentio-dynamic polarisation showed the limiting current and mass transfer coefficient to decrease with increasing concentration of amine derivatives. Adsorption of all amine inhibitors on the copper cathode obeyed Temkin, Flory-Huggin and kinetic adsorption isotherms. The values for free energy of adsorption were indicative of all of the amine inhibitors being strongly adsorbed on the copper surface, while tensiometric measurements showed that the amines reduced the surface tension of the solutions. At the end of the electrodeposition process, scanning electron microscopy (SEM) was employed to determine the influence of the amines on the surface morphology of the copper deposit. The addition of o-phenylenediamine to the copper bath had a strong influence on microstructure, resulting in a strongly adherent and uniform Cu deposit across the entire electrode surface.

A highly efficient synthetic method for expeditious and selective assembly of tetraazopyrenes (TAPy) is reported, based on the novel reaction of electrophilically activated nitroalkanes with aromatic amines. Remarkably, the nitroalkanes play a dual role in this process, also serving as mild and efficient oxidants promoting aromatization of the final product and allowing for the exclusion of a poorly controllable aerobic treatment. © 2017 The Royal Society of Chemistry.