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Several endophytic fungi have been reported to have produced bioactive metabolites. Some of them, including the Induratia species, have the capacity to emit volatile compounds with antimicrobial properties with broad spectrum against human and plant pathogens. The present study aimed to prospect the Induratia species producing volatile organic compounds (VOCs), in carqueja plants used in alternative medicine and coffee plants in Brazil. A total of 11 fungal isolates producing volatile metabolites were obtained by a parallel growth technique, using I. alba 620 as a reference strain. Phylogenetic relationships revealed the presence of at least three distinct species, I. coffeana, I. yucatanensis, and Induratia sp. SPME/GC/MS analyses of the VOCs in the headspace above the mycelium from Induratia species cultured for 10 days on PDA revealed the volatile profile emitted by I. coffeana CCF 572, I. coffeana COAD 2055, I. yucatanensis COAD 2062, and Induratia sp. COAD 2059. Volatile organic compounds produced by I. coffeana isolates presented antimicrobial activity against Aspergillus ochraceus, A. sclerotiorum, A. elegans, A. foetidus, A. flavus, A. tamari, A. tubingensis, A. sydowii, A. niger, A. caespitosus, A. versicolor, and A. expansum, sometimes by decreasing the growth rate or, mainly, by fully inhibiting colony growth. Fifty-eight percent of the target species died after 6 days of exposure to VOCs emitted by I. coffeana CCF 572. In addition, VOCs emitted by the same fungus inhibited the growth in A. ochraceus inoculated into coffee beans, which indicates that plants which have I. coffeana as an endophyte may be protected from attacks by this plant pathogen.

A risk assessment and a source apportionment of the particulate- and gas-phase PAHs were conducted in a high vehicular traffic and industrialized region in southeastern Brazil. Higher concentrations of PAHs were found during summer, being likely driven by the contributions of PAHs in the vapor phase caused by fire outbreaks during this period. Isomer ratio diagnostic and Principal Component Analysis (PCA) identified four potential sources in the region, in which the Positive Matrix Factorization (PMF) model confirmed and apportioned as gasoline-related (31.8%), diesel-related (25.1%), biomass burning (23.4%), and mixed sources (19.6%). The overall cancer risk had a tolerable value, with ∑CR = 4.6 × 10

The continued contamination of water sources by pesticides is a problem that involves the life of aquatic organisms and human health, especially in countries whose economy is based on agriculture. The need to know the quality of drinking water under these circumstances is a priority for the public health of any community. Passive sampling methods allow the determination of long-term environmental pollutants through a single sample collection, reducing time and cost of analyses. One advantage of passive sampling is that it is possible to calculate a time-weighted average (TWA) concentration value or an equilibrium concentration value, depending on the type of device used and the exposure time. Passive sampling techniques using carbon nanomaterials (CNMs) have a high potential for pesticide sampling in aquatic systems. A device for passive sampling manufactured with CNMs in a microextraction system and recyclable materials was calibrated in laboratory exposure conditions over 15 days. The calibration results showed linear accumulation periods between 5 and 10 days. Sampling rates were between 0.014 and 0.146 mL day−1. The sampler was field-tested in the San Francisco river basin in the state of Minas Gerais in Brazil for 7 days. This research allowed for the detection and calculation of TWA concentrations for organochlorine pesticides such as α-HCH, 4,4-DDE, and 4,4-DD in water sources. The manufactured device demonstrated greater sensitivity than the grab sampling processes for the detection of pesticides. The performed passive sampling system using gas chromatography/mass spectrometry (GC/MS) technique allowed for the collection, detection, identification, and quantification of 26 pesticides.

The illicit burn practices on farms promote food contamination that is harmful and must be controlled by improved analytical methods. Polycyclic aromatic hydrocarbons (PAHs), which have high toxic and carcinogenic potential, can contaminate foods, mainly through fire exposure. Considering the toxicity of PAHs, development of sensitive, simple, and solvent-free methods to analyze PAHs in foods is necessary. This work presents the development of a new method to analyze PAHs in eggs using cold fiber-solid-phase microextraction (CF-SPME) and gas chromatography coupled to mass spectrometry (GC-MS). Parameters of temperature extraction, ultrasonic agitation time, sample mass, and modifiers were evaluated to obtain the best CF-SPME conditions. The new method uses a minimal amount of solvent and showed good linearity in the range of 0.0005 to 5.60 μg/g. Detection limits were from 0.0002 to 0.046 μg/g, and quantification limits were from 0.0005 to 0.152 μg/g. The method was applied to PAHs analysis of chicken egg samples from a farm near a site of an uncontrolled tire fire. The concentrations of PAHs in this study ranged from 0.926 to 1.668 μg/g. All PAHs were detected in the samples. The total toxicity was estimated by benzo(a)pyrene equivalent (BaPeq) and did not decrease significantly in the period (6 weeks) of sample collection.

Bisphenol A and phthalates are endocrine disruptors widely used as chemical additives mainly in plastic products, including materials for dentistry procedures. Besides, many plasticizers have been associated with important diseases requiring performed methods for their quantification. In the present study, an alternative method for the determination of bisphenol A (BPA) and phthalate metabolites in saliva was developed and validated using hollow fiber liquid phase microextraction (HF-LPME) for sample preparation and gas chromatography coupled to ion trap mass spectrometry (GC/MS) for analysis. A mixture of octanol and ethyl octanoate (1:1 v/v) was used as an acceptor phase in hollow fiber to extract the analytes from saliva samples. A Doehlert design was performed to optimize the variable sample agitation and extraction time. The HF-LPME-GC/MS method developed for saliva analysis showed good selectivity, linearity (R2 > 0.900), and precision (CV = 0.86–18.68%). Limits of detection and quantification ranged from 0.03 to 0.53 μg L−1 and 0.09 to 1.78 μg L−1, respectively. A high concentration of BPA in the oral cavity and oropharyngeal space is a warning of the possible association with the main cancer of the mouth. The method developed and validated was applied to patients with oral squamous cell carcinoma (study group, n = 16) and patients who did not present any oral lesion (control group, n = 16). A principal component analysis was performed and showed a tendency for the association between oral squamous cell carcinoma (OSCC) and plasticizers.

Multi and comprehensive two-dimensional gas chromatography application have been increasingly mentioned in different countries. This technique increases the efficiency of peak separation in chromatographic analysis, minimizing problems due to the presence of interfering compounds in the analysis, especially in complex matrices. In Latin America, it has been applied to different areas of study. However, biological samples have been reported in a small number of applications. This mini-review addresses studies where the multi and comprehensive two-dimensional gas chromatography technique have been applied to biological samples’ analyses. Biological matrices are generally complex, and sample preparation usually requires a large number of steps to minimize potential interferences. The main areas of study described were related to doping control analysis and biomarker analysis. The urine sample was the main type of biological sample used in the studies. Studies have shown that results obtained by two-dimensional gas chromatography or supported or not by mathematical tools allow high efficiency in solving problems such as coelution. However, the small number of works published with the participation of Latin American researchers indicate that equipment price, especially when mass spectrometry is used as a detector, has a limiting factor in its wide application.

There is actually health concern about the uncontrolled use of pesticides, as some banned pesticides continue to be used in many regions of the world, especially in Latin America. Advanced analytical methods are thus required to detect pesticides in water. Common pesticide analysis is done by grab sampling of water volumes ranging from milliliters to liters. Grab sampling is suitable for moderate to high pesticide concentrations, but fails to detect trace levels and shows only a single-time snapshot of pesticide levels. Alternatively, passive sampling extracts and collects water directly in situ, thus allowing time for pollutants to be accumulated into the sampler. Passive sampling has recently become a major tool for extraction of organic contaminants in surface water, groundwater and wastewater. Diverse pollutants have been studied, such as pesticides, illicit and prescription drugs, metals, polycyclic aromatic hydrocarbons and cyanobacterial microcystin toxins. This review describes the main devices of passive sampling, used for the extraction of pesticides in waters.

To evaluate the release of bisphenol-A glycidyl methacrylate (BisGMA), triethylene glycol dimethacrylate (TEGDMA), bisphenol A (BPA), and phthalates of the composite resin used in the bonding of spurs applied in the treatment of children with anterior open bite and its effects on human keratinocytes. Methodology Saliva samples of 22 children were collected before spur attachment (baseline) and 30 minutes (min) and 24 hours (h) after spur bonding. Analysis was performed using high-performance liquid chromatography (HPLC) coupled to tandem mass spectrometry (HPLC–MS/MS) and gas chromatography coupled to mass spectrometry (GC–MS). Standardized resin increments were added to three different dilutions of the cell culture medium. Keratinocytes (HaCaT) were cultivated in the conditioned media and evaluated for cell viability (MTT) and cell scratch assay. Results The levels of BisGMA (1.74±0.27 μg/mL), TEGDMA (2.29±0.36 μg/mL), and BPA (3.264±0.88 μg/L) in the saliva after 30 min, in comparison to baseline (0±0 μg/mL, 0±0 μg/mL, and 1.15±0.21 μg/L, respectively), presented higher numbers. After 24 h, the levels of the monomers were similar to the baseline. Phthalates showed no significant difference among groups. HaCat cells showed increased viability and reduced cell migration over time after exposure to methacrylate-based resin composites. Conclusion Resin composites, used to attach spurs in children with anterior open bite during orthodontic treatment, release monomers after polymerization and can influence the behavior of human keratinocytes, even at very low concentrations. Orthodontists should be aware of the risks of the resinous compounds release and preventive procedures should be held to reduce patient exposure.

Air quality in large cities has worsened in recent years as a consequence people’s health is directly affected. Among the toxic compounds released to environmental air are polycyclic aromatic hydrocarbons (PAHs), nitrated PAHs (nitro-PAHs), and oxygenated PAHs (oxy-PAHs). Performant methods to analyze these compounds is necessary to enable adequate monitoring of air quality. Thus, this manuscript presents the development of a highly sensitive method to analyze PAHs, nitro-PAHs, and oxy-PAHs collected from ambient air (PM2.5) and the gas phase for a period of one year in the urban area of Belo Horizonte, Brazil. PAHs and their derivatives were extracted by cold fiber solid phase microextraction (CF-SPME) and analyzed by gas chromatography coupled to mass spectrometry (GC/MS). The proposed method allows simultaneous analysis of 16 PAHs, nitro-PAHs and oxy-PAHs, presenting very good limits of detection and quantification, as well as appropriate precision and recovery. The results obtained for the period of one year allowed different studies. The compounds collected simultaneously from gas and particulate phase showed that total concentration of 16 PAHs were higher in the gas phase than in the particulate. On the other hand, nitro-PAHs and oxy-PAHs presented similar concentration in gas and particulate phases. The potential carcinogenicity of PAHs relative to benzo[a]pyrene showed benzo[a]pyrene equivalents of 0.49 ng m−3. The estimated risk of lifetime lung cancer was 5 × 10−5. Principal component analysis and diagnostic ratio was applied for source distribution indicating that burning of gasoline, diesel and biomass accounted for the PAHs profile in ambient air samples.

Bisphenol A (BPA) is an endocrine disrupting chemical able to promote hormone-responsive tumors. The major route of BPA contamination being oral, the aim of the present study was to investigate BPA effects on oral cells. Here, we evaluated the impact of sub-chronic in vivo exposure to BPA and its in vitro effects on neoplastic and non-neoplastic oral cells. We evaluated the oral mucosa of mice chronically exposed to BPA (200 mg/L). The response of keratinocytes (NOK–SI) and Head and Neck (HN) Squamous Cell Carcinoma (SCC), HN12 and HN13 cell lines to BPA was examined. In vivo, BPA accumulated in oral tissues and caused an increase in epithelial proliferative activity. BPA disrupted the function of keratinocytes by altering pro-survival and proliferative pathways and the secretion of cytokines and growth factors. In tumor cells, BPA induced proliferative, invasive, pro-angiogenic, and epigenetic paths. Our data highlight the harmful effects of BPA on oral mucosa and, tumorigenic and non-tumorigenic cells. Additionally, BPA may be a modifier of oral cancer cell behavior by prompting a functional shift to a more aggressive phenotype.

Sample preparation assisted by a cooling system including solid phase microextraction (SPME) has received an increased interest in recent years. In this work, a new cold fiber (CF-SPME) system using thermoelectric cooling is proposed. The system consists of three thermoelectric coolers (Peltier), a heat sink, a recirculation module to dissipate the heat generated on the hot side, and an electric power source to generate the necessary voltage for the system. The Peltier keeps the SPME fiber cool during the extraction process.. This system was used to analyze polycyclic aromatic hydrocarbons (PAHs), and their nitrated (nitro-PAHs) and oxygenated (oxy-PAHs) derivatives, in commercial beers by gas chromatography coupled to mass spectrometry (GC/MS). The analyte's extraction was optimized through Doehlert design. Optimal extraction conditions were obtained with a salt content of 0.6% w/v and beer volume of 700.0 μL. The validated method showed limits of detection (LOD) in the range of 0.003–0.128 μg L−1 and limits of quantification (LOQ) from 0.011 to 0.427 μg L−1. Precision Coefficients of Variation values ranged from 3.0 to 18.7%, and recovery values of the analytes in beer varied between 80.1 and 100.3%. Among the PAHs derivatives evaluated in this study, only 9-fluorenone and 9-nitroanthracene were detected in some samples. Benzo[b]fluoranthene was the most detected analyte in the samples, and at least one PAH was detected in all samples. Principal component analysis (PCA) separated the samples into two groups, mainly due to the high relative concentrations of acenaphthene and chrysene. The cooling approach improved the extraction efficiency and the new system demonstrated high potential for portability and automation.

This article describes the development and validation of a solid-phase microextraction method using direct immersion and cold fiber (DI-CF-SPME) to collect samples in ambient air particulate matter and a gas phase to analyze 16 priority polycyclic aromatic hydrocarbons by gas chromatography mass spectrometry. This method has proven to yield good results for some validation parameters. Limits of detection and quantification ranged from 0.008 ng m−3 to 0.095 ng m−3 and from 0.020 ng m−3 to 0.101 ng m−3, respectively. The inter-assay precision shows a coefficient of variation ranging from 1.01% to 15.75%. The method was applied to the analysis of samples collected in 2014 and 2015 in the urban area of Belo Horizonte, located in southeastern Brazil. The samples were collected next to high-traffic routes and industrial regions using a PM10 (

Acrolein is a pollutant released daily to the indoor environment from different sources. The present study reports the development of a simple and sensitive cold fiber solid phase microextraction sampling method for the determination of acrolein in exhaled air and indoor air by gas chromatography mass spectrometry. O-(2,3,4,5,6-pentafluorobenzyl) hydroxylamine was used as derivatizing agent supported on a 65-μm polydimethylsiloxane-divinylbenzene SPME fiber. An acrolein permeation tube at 326.25 ng min−1 rate was used to generate gaseous standards. The method shows good results for main validation parameters. The limits of detection and quantification were 2.88 and 5.08 μg m−3, respectively, for indoor analysis; and 2.40 and 3.79 μg m−3, respectively, for exhaled air analysis. The precision showed standard deviation ranges from 6.00 to 8.00% for intra-assay analyses and from 8.00 to 10.00% for inter-assay analyses. After optimizing the conditions, analyses of real samples were performed on indoor environments contaminated by cigarette smoke, or heated oil, including pastry shops, restaurants, churros stands, and closed parking cars located in the city of Belo Horizonte, Brazil. Acrolein breaths of exposed people were also determined. A good Pearson correlation coefficient (r = 0.901) was observed between the concentration of acrolein in indoor air and exhaled air, allowing to propose acrolein breath as environmental exposure biomarker.

Metabolomic studies are essential to identify and quantify key metabolites in biological systems. Analysis of amino acids (AA) is very important in target metabolomics studies. Chromatographic methods are used to support metabolite determinations. Therefore, this work presents analysis of 17 AA in Saccharomyces cerevisiae cells (a useful model in the study of cancer metabolism) exposed to sodium selenite and gamma radiation. An improved GC/MS method using propyl chloroformate/propanol as derivatizing reagent was applied to AA determinations. The method exhibited good linearity in the range of 0.08–600.00 mg L−1; limits of determination from 0.04 to 1.60 mg L−1; limits of quantification from 0.08 to 2.76 mg L−1; repeatability ranging from 1.9 to 11.4 %; and precision ranging from 2.8 to 13.8 %. The correlations between selenite/gamma radiation with AA profile was investigated to establish candidates for cancer biomarkers. The analyses of yeast cultures found high concentrations of amino acids, such as Alanine, Serine, Glutamate, and Lysine, which might be associated with the development of metabolic adaptations of cancer based on its high demand for biomass and energy, found both in this model and neoplastic cells.

Ischemic stroke is a neurovascular disorder caused by reduced or blockage of blood flow to the brain, which may permanently affect motor and cognitive abilities. The diagnostic of stroke is performed using imaging technologies, clinical evaluation, and neuropsychological protocols, but no blood test is available yet. In this work, we analyzed amino acid concentrations in blood plasma from poststroke patients in order to identify differences that could characterize the stroke etiology. Plasma concentrations of sixteen amino acids from patients with chronic ischemic stroke (n = 73) and the control group (n = 16) were determined using gas chromatography coupled to mass spectrometry (GC-MS). The concentration data was processed by Partial Least Squares-Discriminant Analysis (PLS-DA) to classify patients with stroke and control. The amino acid analysis generated a first model able to discriminate ischemic stroke patients from control group. Proline was the most important amino acid for classification of the stroke samples in PLS-DA, followed by lysine, phenylalanine, leucine, and glycine, and while higher levels of methionine and alanine were mostly related to the control samples. The second model was able to discriminate the stroke subtypes like atherothrombotic etiology from cardioembolic and lacunar etiologies, with lysine, leucine, and cysteine plasmatic concentrations being the most important metabolites. Our results suggest an amino acid biosignature for patients with chronic stroke in plasma samples, which can be helpful in diagnosis, prognosis, and therapeutics of these patients.

This work presents the application of a simple and sensitive method developed for the simultaneous analysis of the levels of twenty two underivatizated free L-amino acids in plasma samples of preeclampsia patients by high performance liquid chromatography coupled to high-resolution mass spectrometer (LC-HRMS) using hydrophilic interaction liquid chromatography (HILIC) silica column. The linearity was evaluated in the range of 0.009 to 8.018 µmol L-1 showing coefficients of determination (R2) in the range of 0.999 to 0.911 (p < 0.05). The intra- and inter-day precisions were above of 9.84 and 15.31, respectively. The limits of detection (LOD) and quantification (LOQ) were in the range of 0.003 to 0.683 µmol L-1 and 0.009 to 2.276 µmol L-1, respectively. The results of the investigation of free L-amino acids showed that the levels of GABA, Arg, Ser, Leu, Ile, Met, Val, Ala, Gly, Bet, His and Lys in plasma of patients with preeclampsia were significantly different from healthy patients.

Endocrine disrupting chemicals (EDCs) such as phthalates and bisphenol A (BPA) are substances that may interfere with the actions of endogenous hormones and may be associated with estrogen-related diseases such as endometriosis. This paper describes a case-control study to evaluate the relationship between endometriosis and phthalates and BPA exposure, through biomarkers analysis in urine. The biomarkers of exposure analyzed were metabolites mono-methyl phthalate, mono-isobutyl phthalate (MiBP), mono-butyl phthalate, mono-cyclohexyl phthalate, mono-(ethylhexyl) phthalate, mono-isononyl phthalate, mono-octyl phthalate (MOP), mono-benzyl phthalate and BPA. Urine samples were collected from women aged 18–45 years old. The Study group (n = 30) and Control group (n = 22) were composed of women using as criteria confirmation of endometriosis by videolaparoscopy surgery with histological diagnosis and the absence of the disease, respectively. The analytical method used liquid phase microextraction with determination by gas chromatography coupled to mass spectrometry. The concentrations of biomarkers were adjusted by the creatinine concentration in urine samples of the two groups. The values obtained for the Study Group were compared with the values obtained for the Control Group. The chi-square test and Odds Ratio were used to compare dichotomized phthalate metabolites and BPA metabolite by endometriosis. All nine metabolites were found in different concentrations in the urine samples in both groups The phthalate metabolites that had the highest concentrations, were MOP and MiBP, in which the values of 670 μg g−1 and 560 μg g−1, respectively. The relationship between endometriosis and the all grouped metabolites was evaluated, but was not statistically significant with a 95% CI [X2 (df = 1) = 1.471; p = 0.225]. However, odds ratio (95% confidence interval - CI) for MiBP, which was found at relatively high concentrations in the samples, by endometriosis was 1.929 (0.507–7.332). The food habits and gynecologic history were evaluated and no difference was found between groups. Although no evidences of causal link was found, this study contributes to show that other analysis must be done for evaluating the association between endometriosis and compounds suspected of being EDC.

CNPq - Conselho Nacional de Desenvolvimento Científico e Tecnológico FAPEMIG - Fundação de Amparo à Pesquisa do Estado de Minas Gerais CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior Banana characteristics could provide yeast growth and support the action of yeast to produce beverages. The effects of enzymatic treatment, centrifugation, commercial yeast and two selected strains of Saccharomyces cerevisiae were investigated using the fermented banana Terra. Volatile organic compounds (VOCs) were determined by solid phase microextraction using gas chromatography mass spectrometry. The results showed that the condition employing enzymatic treatment, centrifugation and wet commercial yeast provided maximum ethanol yield (86%) and effiency (98%). Twenty-two compounds of distinct chemical classes were analysed including alcohols, esters, acids and aldehydes. The concentrations of the VOCs differed depending on the fermentation condition and were more influenced by using different yeasts. The limits of detection and quantification ranged from 0.056 to 2.694 mg L–1 and 0.057 to 2.904 mg L–1 respectively. Among the most prevalent VOCs the higher alcohols ranged from 353 to 1017 mg per 100 mL of anhydrous alcohol. The fermented banana studied showed a composition similar to other fermented fruit pulps.

This research describes a solid-phase microextraction device using carbon nanomaterials supported on steel threads. The device was used to pre-concentrate and extract 24 pesticides in water. The carbon nanomaterials were obtained by a chemical vapor deposition (CVD) process, using methane and acetonitrile as carbon source. The different pesticides were separated, detected, and quantified using gas chromatography coupled to mass spectrometry (GC-MS). The system, optimized and validated in the laboratory, presented good results. Linearity was between 0.0007 and 50.00 μg L−1, with determination coefficients greater than 0.9. The detection and quantification limits were in the range of 0.0002–1.1309 μg L−1 and 0.0007–3.7320 μg L−1, respectively. The studied pesticides presented recovery values in the range of 70 ± 8 to 123 ± 18%. Carbon nanomaterials exhibited high thermal and mechanical resistance, as the same fiber could be used for approximately 300 extractions. The device was applied to analyze environmental water samples collected from the Sao Francisco river basin in Brazil and in the Chinampas in Mexico City.

In this work, a new potential route to convert free fatty acids to long chain nitriles and fuel gas (H2/hydrocarbon) intermediated by Fe nitrate is proposed. Precursors based on Fe3+/RCOO-/NO3- were prepared by mixing Fe nitrate and oleic acid at the molar ratios 1:1 and 1:3. After pyrolytic decomposition at 550 °C, these precursors yielded three fractions, i.e. solid (8−27 wt%), liquid (22−51 wt%) and gaseous (41−51 wt%). TG, XRD, SEM, Raman, Mossbauer, CHN analyses of the solid products showed the presence of 25–52% carbon with reduced iron oxides (Fe3O4 and FeO). Analyses of the liquid fraction by GCMS, 1H/13C–NMR, CHN and FTIR clearly indicated the formation of nitriles as the main products, with selectivity of ca. 80 % and small amounts of hydrocarbons and ketones. A large gas fraction composed mainly by hydrogen and hydrocarbons (especially C3) was also formed.

The extensive use of pesticides promotes environmental contamination, mainly in surface and ground waters. However, they remain at very low concentration and present wide degradation level requiring the use of efficient devices for pesticides passive sampling. In this study, a new in situ passive sampling device was developed for monitoring and estimating time-weighted average (TWA) of pesticides in waters. The device was made with simple, recyclable and cheap materials. The sampling system involves the liquid phase microextraction technique with hollow fiber in two-phases mode. Pesticides determination was done by gas chromatography coupled to mass spectrometry. The method was optimized and validated for the determination of 29 pesticides in water, showing good linearity in the range between 0.012 and 40.00 μg L−1 with determination coefficients of R2 > 0,9649. Limit of detection (LOD) ranged from 0.009 to 0.557 μg L−1 and limit of quantification (LOQ) from 0.012 to 0.802 μg L−1. The recoveries of spiked pesticides in water samples were in the range from 96 to 130%. The method was applied to forty environmental water samples collected at Sao Francisco river basin, Brazil. The highest detection frequency was found for the pesticides 4,4-DDE, 4,4-DDD and propazine. They were detected in more than 20 percent of the samples.

Polycyclic aromatic hydrocarbons (PAHs) are food contaminants; besides, their oxygenated (oxy-PAHs) and nitrated (nitro-PAHs) derivatives have also been detected in some foods. This is worrying because these derivatives may be more toxic than PAHs. This study presents a new method for the determination of PAHs and their oxygenated and nitrated derivatives in coffee brew. The analytes were extracted by cold fiber solid phase microextraction (CF-SPME) with analysis by gas chromatography/mass spectrometry. The developed method presented good precision with intra-assay and inter-assay, ranged from 4.5 to 16.4%, and from 9.8 to 19.8%, respectively. Recovery ranged from 82.1 to96.3% and linearity showed good adjustment presenting determination coefficients (R2) from 0.980 to 0.999. The limits of quantification ranged from 0.025 to 0.224 μg L−1. The proposed method is simple, versatile, allows simultaneous extraction of PAHs, nitrated and oxygenated derivatives and was successfully applied to the analysis of commercial coffee samples. Benzo(k)fluoranthene, benzo(b)fluoranthene, pyrene, acenaphthylene and acenaphthene are the most abundant PAHs found in samples. In addition, 5,12-naphthacenequinone was the most abundant oxy-PAH and 1-nitropyrene was the most abundant nitro-PAH.

This study reports a direct immersion solid-phase microextraction method (DI-SPME) for the analysis of persistent organic pollutants (POPs), especially pesticide endosulfan, and 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) present at trace levels in water samples. The identification and quantification was performed by gas chromatography coupled to mass spectrometry (GC/MS). The optimized and validated methodology showed LOQs for endosulfan α and endosulfan β of 916.0 and 126.0 ng L−1 respectively, and for 2,3,7,8-TCDD of 10.0 ng L−1. Subsequently bentonite and vermiculite materials modified with cetyltrimethylammonium (CTA+) (B3CTA, B7CTA and B15CTA; V3CTA, V7CTA and V15CTA) were prepared, characterized and studied for the remediation of POPs in water.

Aim: The increasing use of cocaine (COC) during breastfeeding has led to growing concern about exposure of infants. Therefore, to study this exposure, a new method to analyze COC and benzoylecgonine in breast milk was developed. Methodology: A new extraction method was used for the first time to analyze COC and its major metabolite, benzoylecgonine, in breast milk using magnetic carbon nanotubes partially doped with nitrogen. Results: The calibration curves were linear in the range 5.0–180.0 ng ml-1. The limit of quantification was 5.0 ng ml-1. Coefficients of variation were between 3.2 and 13.9%. Recovery was between 89.6 and 99.2%. Conclusion: The proposed method is simple, efficient and suitable to determine analytes in breast milk.

Bile acids (BAs) are derived from cholesterol and produced in the liver. The most abundant bile acids in humans are usually conjugated with glycine and taurine and are divided into primary BAs such as cholic acid (CA) and chenodeoxycholic acid (CDCA) and secondary BAs like deoxycholic acid (DCA), lithocholic acid (LCA) and ursodeoxycholic acid (UDCA). The differences amongst individual bile acids (BAs) are significant in order to distinguish different pathological processes and exposure to chemical compounds. Hollow fiber based liquid-phase microextraction (HF-LPME) is a technique that combines sample cleansing, extraction and the concentration of analytes, where a hydrophobic porous capillary membrane is impregnated with an organic extraction solvent and the lumen is filled with microliters of a phase acceptor both organic by nature. The aim of this study was to develop a new method to extract bile acids from plasma through HF-LPME of two phases (octanol as the acceptor phase) using LCMS-IT-TOF. The optimized two-phased LPME procedure for the extraction of bile acids showed limits of detection 1.0 μg L(-1) and limits of quantification of 5.0 μg L(-1). The intra-assay precision ranged from 2.1 to 11.9%. The method developed was linear over the range of 5.0-200.0 μg L(-1) for all analytes. The hollow-fiber liquid-phase microextraction method was applied to human plasma from workers exposed to organic and halogenated solvents and also to unexposed volunteers. The method is simple, low cost and it does not require large amounts of organic solvents, therefore it is quite suitable for the analysis of bile acids exposed to hepatotoxic compounds.

Polycyclic aromatic hydrocarbons (PAHs) are carcinogenic to humans and can be found in a variety of environments. This paper describes a cold fiber (CF) solid-phase microextraction (SPME) sampling method with gas chromatography mass spectrometry (GC/MS) to identify 16 PAHs in artisanal cachaca. The method yields good results for some validation parameters. The LOD and LOQ ranged from 0.01 μg L −1 to 0.08 μg L− 1 and from 0.02 μg L −1 to 0.22 μg L −1, respectively. The intra-assay precision shows a coefficient of variation (CV) ranging from 5% to 16%, and the recovery tests varied from 74 ± 12% to 95 ± 7%. The proposed method was attractive as this method extracted higher amounts of PAHs in a single extraction procedure compared with conventional approaches. The method was applied to the analyses of PAHs in 29 artisanal cachaca samples collected in the state of Minas Gerais in Brazil. Average PAH concentrations in these samples were in the range of 0.14 ± 0.06 μg L −1 fluoranthene to 5.77 ± 0.35 μg L −1 dibenzo[a,h]anthracene. The benzo[a]pyrene equivalent (BaPeq) was calculated to assess the health risks associated with PAH exposure. Principal component analysis (PCA) was used to discriminate between different sources of contamination in cachaca.

Phthalates used as plasticizers in the manufacture of household containers can potentially be transferred to foods that are stored or heated in these plastic containers. Phthalates are endocrine disruptor compounds (EDC) and are found in very low concentrations in foods, thus, highly sensitive analytical techniques are required for their quantification. This study describes the application of a new method developed for analyzing the migration of dibutylphthalate (DBP) and benzylbutylphthalate (BBP) from plastic food containers into liquid food simulants. This new method employs the technique of solid phase microextraction cooled with liquid nitrogen. The analysis was conducted by gas chromatography/mass spectrometry (GC/MS) using a polyacrylate fiber. Ultrapure water was used as a simulant for liquids foods, and both new and used plastic containers were placed in a domestic microwave oven for different periods of time at different power levels. The limits of detection for DBP and BBP were 0.08 µg/L and 0.31 µg/L, respectively. BBP was not found in the samples that were analyzed. DBP was found in concentrations ranging from

Polycyclic aromatic hydrocarbons (PAH) are carcinogenic to humans and can be found in various environments. This paper describes a cold fiber (CF) solid-phase microextraction (SPME) sampling method with gas chromatography mass spectrometry (GC/MS) to identify 16 PAH in spring water. The method yields good results for some validation parameters. The LOD and LOQ ranged from 7.10 to 57.96 ng L − 1 and from 23.60 to 193.19 ng L − 1 , respectively. The intra-assay precision shows a coefficient of variation (CV) ranging from 4.38 to 17.65%, and recovery tests varied from 76 ± 13% to 99 ± 8%. The proposed method was attractive, as it extracted higher amounts of PAH in a single extraction procedure in comparison with conventional approaches. The method was applied to the analyses of PAH in twenty-four spring water samples collected in Divinopolis City, Minas Gerais, Brazil. Average PAH concentrations were in the range of 62.80 ± 10.40 ng L − 1 for Benzo[ a ]anthracene and 146.58 ± 98.98 ng L − 1 for Benzo[ a ]pyrene.

Naphthalene, a highly volatile polycyclic aromatic hydrocarbon (PAH), is classified as possibly carcinogenic to humans and can be found in various environments. This paper describes a cold fiber (CF) solid phase microextraction (SPME) sampling method coupled with gas chromatography/mass spectrometry (GC/MS) for determining naphthalene in ambient air. The method uses a 100 μm polydimethylsiloxane (PDMS) fiber to generate gaseous standards using a permeation tube. The method shows good results for many validation parameters. The intra-assay precision shows a relative standard deviation (RSD) ranging from 1.04 to 8.11%; the limit of detection (LOD) is 0.33 ± 0.01 μg/m 3 , and the quantification limit (LOQ) is 0.55 ± 0.01 μg/m 3 . The method was applied to the determination of naphthalene from real samples collected from indoor and outdoor air. The results have shown the ability of the method to measure trace levels of naphthalene in the air in different environments.

The determination of the concentrations of l-amino acids in cerebrospinal fluid (CSF) has been used to gain biochemical insight into central nervous system disorders. This paper describes a microwave-assisted derivatization (MAD) method using N,O-bis-(trimethylsilyl)trifluoroacetamide (BSTFA) as a derivatizing agent for determining the concentrations of l-amino acids in human CSF by gas chromatography with mass spectrometry (GC/MS). The experimental design used to optimize the conditions showed that the optimal derivatization time was 3min with a microwave power of 210W. The method showed good performance for the validation parameters. The sensitivity was very good, with limits of detection (LODs) ranging from 0.01μmolL(-1) to 4.24μmolL(-1) and limits of quantification (LOQs) ranging from 0.02 to 7.07μmolL(-1). The precision, measured using the relative standard deviation (RSD), ranged from 4.12 to 15.59% for intra-day analyses and from 6.36 to 18.71% for inter-day analyses. The coefficients of determination (R(2)) were above 0.990 for all amino acids. The optimized and validated method was applied to the determination of amino acid concentrations in human CSF.

Sugarcane spirits are defined as beverages with an alcohol content ranging from 38 to 54 % v/v at 20 °C, obtained from the simple alcoholic distillation of sugarcane or fermented sugarcane must. Fruit spirits may be obtained directly from fruit or from fruit must that may or may not contain seeds by distillation, and present specific organo- leptic characteristics and an alcohol content of 36 to 54 % v/ v at 20 °C. The physicochemical and sensory qualities of these beverages are dependent on the nature and quality of the raw materials, fermentation, distillation and aging, and are organoleptically characterised by the presence of volatile organic compounds (VOC) (organic acids, aldehydes, esters, higher alcohols, terpenes, lactones and others). This paper presents studies performed to evaluate VOC in spirits. Among the volumetric and instrumental methods described to evaluate VOC in spirits, chromatographic methods are the most cited. Chromatographic techniques employed include high performance liquid chromatography, gas chromatogra- phy with flame ionisation detection, gas chromatography with mass spectrometric detection and two-dimensional gas chromatography with time-of-flight mass spectrometry.

This paper shows the use of exhaled air as a biomonitoring method to assess perchloroethylene (PERC) environmental and occupational exposure. A sensitive, fast, and solvent free analytical method was developed to determine PERC in ambient and exhaled air of individuals occupationally exposed. The developed method used cold fiber solid phase microextraction (CF-SPME) as the sampling technique, and a standard permeation method to simulation of air matrix. The analysis were conducted by gas chromatography coupled to mass spectrometry (GC/MS). The methods were validated and were found to be precise, linear and sensitive for environmental and biological monitoring. The developed methods were applied to twenty-seven sampling points spread across Belo Horizonte city, Brazil, twenty four dry cleaners, an electroplating industry, a research laboratory, and an automotive paint preparation shop. The results of ambient air analyses ranging from 14.0 to 3205.0µgm-3 with median concentration of 599.0µgm-3. Furthermore, sampling of exhaled air of individuals occupationally exposed presented results ranging from 6.0 to 2635.0µgm-3 with median concentration of 325.0µgm-3. The strong correlation observed between ambient and exhaled air (r =0.930) demonstrates that exhaled air is a suitable biomarker for evaluating occupational exposure to PERC.

This paper describes a simple and quick method for sampling and also for carrying out the preconcentration of pesticides in environmental water matrices using two-phased hollow fiber liquid phase microextraction (HF-LPME). Factors such as extraction mode, time, solvents, agitation, and salt addition were investigated in order to validate the LPME method. The following conditions were selected: 6 cm of polypropylene hollow fiber, ethyl octanoate as an acceptor phase, and extraction during 30 min under stirring at 200 rpm. The optimized method showed good linearity in the range of 0.14 to 200.00 μg L−1; the determination coefficient (R2) was in the range of 0.9807–0.9990. The LOD ranged from 0.04 μg L−1to 0.44 μg L−1, and LOQ ranged from 0.14 μg L−1to 1.69 μg L−1. The recovery ranged from 85.17% to 114.73%. The method was applied to the analyses of pesticides in three environmental water samples (a spring and few streams) collected in a rural area from the state of Minas Gerais, Brazil.

Endocrine disrupting compounds are organic compounds that are present in low concentrations in food and environmental samples. These compounds are suspected to cause dysfunction of the endocrine system in humans and animals. This chapter briefly presents an overview on some important endocrine disrupting compounds as well as matrices, where their determination is pertinent. Advanced sample preparation methods, using low solvent amounts, together with new multidimensional analytical methods to perform the analysis of endocrine disrupting compounds are also discussed. Comprehensive two-dimensional gas chromatography has been successfully applied to the analysis of some endocrine disrupting compounds. Dibutylphthalate, benzylbutylphthalate, nonylphenol, and octylphenol were quantified using comprehensive two-dimensional gas chromatography with a flame ionization detector. The merit parameters of the analytical method were determined. The compounds were evaluated throughout a concentration range of 0.2–6.0 μg L−1. LOD ranging from 0.07 to 0.32 μg L−1 and LOQ ranging from 0.17 to 0.55 μg L−1 were obtained for these four compounds.

Polycyclic aromatic hydrocarbons (PAHs) were analyzed from ambient air particulate matter

Volatile organic compounds (VOC) are the total organic compounds that contribute to photochemical ozone formation. They have a vapor pressure greater than 0.013 kPa at 298 K (according to the American Society for Testing and Materials (1996)), 0.01 kPa at 293 K (according to the European Union (1999)), or 10 Pa at 298 K (according to the U.S. Environmental Protection Agency (1999)), with a lower boiling point limit of 50–100°C and an upper boiling point limit of 240–260°C. VOC include countless potentially hazardous substances released to the outdoor or indoor environment. The prevention or reduction of exposure to VOC in the air requires qualitative and quantitative analysis of these chemical agents. A correct assessment of human exposure to VOC requires appropriate and efficient methods of sampling and analysis. The authors present a survey of VOC definitions, an analytical discussion of the necessity and viability of exposure studies, the principal VOC studied, and a critical revision of methods of sam...

The frying of foods in the home can be a cause of indoor pollution due to the formation of acrolein. The emission of acrolein formed during frying in soybean, corn, canola, sunflower and palm oils was studied. A GC/MS method has been developed to determine acrolein in French fries using SPME as the sampling technique after derivatization with 2,4-dinitrophenylhydrazine (DNPH). Optimum SPME conditions included desorption at 250°C for 2min after an adsorption time of 10min at room temperature. The method presented good resolution, repeatability, detection and quantification limits, and linearity of response. French fries were prepared in five different oils with four frying steps. The results showed that changes in acrolein concentration occurred after frying potatoes in different types of oil and at different frying cycles. Potatoes fried in soybean oil contained the lowest concentration of acrolein. Shoestring potatoes contained a lower concentration of acrolein than potato chips and French fries, respectively, because of the higher surface/volume ratio.

This article presents an overview of the different analytical methods available for performing pesticide degra- dation studies in water and environmental samples by different processes. How long the pesticide remains in the environ- ment depends on how strongly it is bounded by other components and how readily it is degraded. It is also depends on the environmental conditions at the time of application, pH, temperature, soil and water content. The degree of mineralization achieved under advanced oxidation processes (AOP), photo-Fenton reactions (FR), and ozonation processes, and the iden- tity of by-products of a large number of compounds belonging to the major pesticide families pirethroides, organochlo- rides and organophosphorus compounds are presented. Critical comments are aimed at emphasizing the lack of suitable analytical methods adequate to determine the kinetics of both the formation and disappearance of by-products and to iden- tify their chemical structures. More specifically, the crucial role of gas chromatography and liquid chromatography in combination with mass spectrometry is described. In the following manuscript, an overview of the pesticide degradation phenomena is given, and an attempt is made to predict how factors and conditions influence the phenomena. SPME and GC/MS are sufficiently accurate methods to support the identification of pesticides in different degradation processes.