Biomonitoring of polycyclic aromatic hydrocarbons in Brazilian pregnant women: Urinary levels and health risk assessment.

Over the years, humans have been continuously exposed to several compounds directly generated by industrial processes and/or present in consumed products. Polycyclic aromatic hydrocarbons (PAHs) are legacy pollutants ubiquitous in the environment and represent the main chemical pollutants in urban areas. Worldwide, studies that aim to understand the impacts of exposure to these chemicals have gained increasing prominence due to their potential toxicity profile, mainly concerning genotoxicity and carcinogenicity. Human biomonitoring (HB) is an analytical approach to monitoring population exposure to chemicals; however, these studies are still limited in Brazil. Thus, this work aimed to evaluate the exposure of Brazilian pregnant women to PAHs through HB studies. Besides, the risk characterization of this exposure was performed. For this purpose, urine samples from 358 Brazilian pregnant women were used to evaluate 11 hydroxylated metabolites of PAHs employing gas chromatography coupled to mass spectrometry. The 1OH-naphthol and 2OH-naphthol were detected in 100% of the samples and showed high levels, corresponding to 16.99 and 3.62 µg/g of creatinine, respectively. 2OH-fluorene (8.12 µg/g of creatinine) and 9OH-fluorene (1.26 µg/g of creatinine) were detected in 91% and 66% of the samples, respectively. Benzo(a)pyrene (BaP) metabolites were detected in more than 50% of the samples (0.58-1.26 µg/g of creatinine). A hazard index of 1.4 and a carcinogenic risk above 10-4 were found for BaP metabolites in the risk characterization. Therefore, our findings may indicate that exposure to PAHs poses a potential risk to pregnant women's health and a high probability of carcinogenic risk due to their exposure to BaP. Finally, this work shows the need for more in-depth studies to determine the sources of exposure and the implementation of health protection measures regarding the exposure of the Brazilian population to PAHs.

Comparative assessment of the degradation of 2-methylisoborneol and geosmin in freshwater using advanced oxidation processes.

Traditional methodologies of conventional drinking water treatment are unable to remove some chemical compounds, such as those that cause odor and taste in drinking water. The present work aims to evaluate the efficiency of advanced oxidations processes, using UV radiation, O3 and O3 + UV in the degradation of geosmin (GSM) and 2-methylisoborneol (2-MIB) in synthetic samples. The efficiency of the processes was monitored by Gas Chromatography coupled with Mass Spectrometry using solid phase microextration technique. Experiments were carried out for 45 min with samplings every 15 min. The degradation results showed that UV radiation alone was not efficient for the degradation of both compounds. The fasted decay was observed by the combined use of O3 and UV with an ozone concentration of 15.84 mg L-1. Under these conditions, the final concentration of GSM was below the limit of quantification, so that approximately 99% of the initial concentration was degraded, while 2-MIB was degraded by 95%. With the same O3 concentration without the use of UV radiation, 63% and 65.7% of MIB and GSM, respectively, were removed. Higher efficiency of the treatment was observed with a higher O3 concentration which allows a shorter reaction time.

Microdroplet-captured tapes for rapid sampling and SERS detection of food contaminants.

Simple, effective, and rapid detection of chemically relevant hazards is a highly desirable research goal, which can provide early-warning information to improve the patient-care outcomes for public health. Here, we introduce a microdroplet-captured tape toward rapid SERS screening of food contaminants. The dominant sensing unit lies on functionalized microwell in conductive carbon tapes, which is simply prepared by physical punching, magnetron sputtering and electrochemical deposition of Au nanodendrites. The tape-based sensors not only possess highly branched Au nanodendrites in microwell for promoting SERS activity, but also enable anchoring the microdroplets via direct dip-pulling from pristine analytes solutions upon sticky incorporated on a glove. Early-warning SERS detection of food contaminants including Sudan-1, thiram, and thiabendazole from the real samples can be achieved by such simple sampling method. These tape-based sensors with a facile operation module and accessible signal read-out represent an innovative point-of-care testing (POCT) device for forensic, military, consumer protection, environmental monitoring, and food safety applications.

Capillary electrophoresis method for the determination of (R)-dapoxetine, (3S)-3-(dimethylamino)-3-phenyl-1-propanol, (S)-3-amino-3-phenyl-1-propanol and 1-naphthol as impurities of dapoxetine hydrochloride.

A capillary electrophoresis method was developed and validated for the determination of the purity of dapoxetine with regard to the related substances (3S)-3-amino-3-phenylpropan-1-ol, (3S)-3-(dimethylamino)-3-phenylpropan-1-ol, 1-naphthol and the enantiomer (R)-dapoxetine. The separation was based on a dual selector system, which was optimized by a fractional factorial resolution V + design followed by a central composite face centered design with star distance 1 and Monte Carlo simulations for defining the design space. The optimized background electrolyte consisted of a 50 mM sodium phosphate buffer, pH 6.3, containing 45 mg/mL sulfated γ-cyclodextrin and 40.2 mg/mL 2,6-dimethyl-ß-cyclodextrin. Separations were carried out in a 23.5/32 cm, 50 µm fused-silica capillary employing a separation voltage of 9 kV at 15 °C. Following robustness testing using a Plackett-Burman design the method was validated according to the International Council on Harmonization guideline Q2(R1) in the range of 0.05-1.0% relative to the dapoxetine concentration. The method was applied to the analysis of drug substance and a commercial tablet. Data regarding the enantiomeric purity of dapoxetine obtained by the capillary electrophoresis assay were comparable to the data obtained by an enantioselective HPLC method.

Analysis of unauthorized Sudan dyes in food by high-performance thin-layer chromatography.

Food authenticity and food safety are of high importance to organizations as well as to the food industry to ensure an accurate labeling of food products. Respective analytical methods should provide a fast screening and a reliable cost-efficient quantitation. HPTLC was pointed out as key analytical technique in this field. A new HPTLC method applying caffeine-impregnated silica gel plates was developed for eight most frequently found fat-soluble azo dyes unauthorizedly added to spices, spice mixtures, pastes, sauces, and palm oils. A simple post-chromatographic UV irradiation provided an effective sample cleanup, which took 4 min for up to 46 samples in parallel. The method was trimmed to enable 23 simultaneous separations within 20 min for quantitation or 46 separations within 5 min for screening. Linear (4-40 ng/band) or polynomial (10-200 ng/band) calibrations of the eight azo dyes revealed high correlation coefficients and low standard deviations. Limits of detection and quantification were determined to be 2-3 and 6-9 ng/zone, respectively. After an easy sample extraction, recoveries of 70-120% were obtained from chili, paprika, and curcuma powder as well as from chili sauce, curry paste, and palm oil spiked at low (mainly 25-50 mg/kg) and high levels (150-300 mg/kg). For unequivocal identification, the compound in a suspect zone was eluted via a column into the mass spectrometer. This resulted in the hyphenation HPTLC-vis-HPLC-DAD-ESI-MS. Graphical abstract Simplified clean-up by UV irradiation for Sudan dye analysis in food by HPTLC-vis-HPLC-DAD-ESI-MS.

UV-based advanced oxidation processes for the treatment of odour compounds: efficiency and by-product formation.

The occurrence of the taste and odour compounds geosmin and 2-methyl isoborneol (2-MIB) affects the organoleptic quality of raw waters from drinking water reservoirs worldwide. UV-based oxidation processes for the removal of these substances are an alternative to adsorption and biological processes, since they additionally provide disinfection of the raw water. We could show that the concentration of geosmin and 2-MIB could be reduced by VUV irradiation and the combination of UV irradiation with ozone and hydrogen peroxide in pure water and water from a drinking water reservoir. The figure of merit EE/O is an appropriate tool to compare the AOPs and showed that VUV and UV/O(3) yielded the lowest treatment costs for the odour compounds in pure and raw water, respectively. Additionally, VUV irradiation with addition of ozone, generated by the VUV lamp, was evaluated. The generation of ozone and the irradiation were performed in a single reactor system using the same low-pressure mercury lamp, thereby reducing the energy consumption of the treatment process. The formation of the undesired by-products nitrite and bromate was investigated. The combination of VUV irradiation with ozone produced by a VUV lamp avoided the formation of relevant concentrations of the by-products. The internal generation of ozone is capable to produce ozone concentrations sufficient to reduce EE/O below 1 kWh m(-3) and without the risk of the formation of nitrite or bromate above the maximum contaminant level.

A monoclonal antibody-based immunosensor for detection of Sudan I using electrochemical impedance spectroscopy.

Sudan I monoclonal antibodies (Mabs) were prepared by hybridoma technique and firstly used to develop a Sudan I immunosensor by immobilizing the Mabs on a gold electrode. o-Mercaptobenzoic acid (MBA) was covalently conjugated on the gold electrode to form a self-assembled monolayer (SAM). The immobilization of Sudan I Mabs to the SAM was carried out through a stable acyl amino ester intermediate generated by 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC) and N-hydrosuccinimide (NHS), which could condense antibodies reproducibly and densely on the SAM. The changes of the electrode behavior after each assembly step were investigated by cyclic voltammetric (CV) technique. The Sudan I concentration was measured through the increase of impedance values in the corresponding specific binding of Sudan I and Sudan I antibody. A linear relationship between the increased electron-transfer resistance (Ret) and the logarithmic value of Sudan I concentrations was found in the range of 0.05-50 ng mL(-1) with the detection limit of 0.03 ng mL(-1). Using hot chili as a model sample, acceptable recovery of 96.5-107.3% was obtained. The results were validated by conventional HPLC method with good correlation. The proposed method was proven to be a feasible quantitative method for Sudan I analysis with the properties of stability, highly sensitivity and selectivity.

Assessment of pollution along the Northern Iberian shelf by the combined use of chemical and biochemical markers in two representative fish species.

Muscle concentrations of organochlorinated compounds as well as biliary levels of polycyclic aromatic hydrocarbons (PAHs) and alkylphenols (APEs) were determined in two different fish species, the four-spotted megrim (Lepidorhombus boscii) and the pouting (Trisopterus luscus) collected along the Northern Iberian coast. Additionally, a set of biochemical markers namely, 7-ethoxyresorufin O-deethylase (EROD), UDP-glucuronosyltransferase (UGT) and catalase (CAT) were measured in liver subcellular fractions. Chemical analysis indicated geographical differences in pollutant loads that were further reinforced by biomarker responses. Thus, EROD activity showed a good correlation with the amount of PCBs bioaccumulated in muscle tissue of both fish species. Elevated UGT activity was observed in those individuals highly exposed to APEs and 1-naphthol. The study reinforces the need to select representative sentinel species from different habitats for biomonitoring purposes and provides further support for the use of biomarkers in assessing the health of coastal areas.

[Enzyme-linked immune sorbent assay for PR-toxin in taxonomical assessment of fungi belonging to the genus Penicillium Link].

The use of an indirect competitive enzyme-linked immune sorbent assay (ELISA) involving polyclonal rabbit antibodies against BSA-conjugated PR-toxin (sensitivity, 1 ng/ml) established the ability to synthesize PR-toxin in 18 out of 35 morphologically identified strains of Penicillium roqueforti and P. chrysogenum. The results indicate that ELISA for PR-toxin may be used in assessing the taxonomical position of terverticillate penicillia in the presence of other micotoxins.

Compost stability assessment using a secondary metabolite: geosmin.

Composting is a process involved not only in transformation of organic matter (OM), but also for transition of the microbial community. Microorganisms can directly provide important information on the stages and characteristics of composting. This paper was aimed at characterizing compost stability by a microbial secondary metabolite, geosmin, which is a volatile compound presenting an earthy smell. Since secondary metabolite production is dependent on the nutrient state of microorganisms, its production in association with physical and chemical parameters was monitored in the laboratory-scale and plant-scale composting processes. The results showed that the peaked geosmin liberation was consistent with stable state of composting indicated by the ambient temperature achieved, a slightly alkaline product and steady states of dissolved organic carbon (DOC), N and P contents and OM degradation in the laboratory-scale experiment. It was also in accordance with the stability identified by the facilities and CO2 respiration rate in the plant-scale composting. In addition, the production of geosmin was correlated with the C/N ratio for the solid sample. These results demonstrated that geosmin levels could be used as an index for the compost stability assessment in different composting processes with various organic solid wastes.