Determination and Profiling of Human Skin Odors Using Hair Samples.

Background. There is no gold standard method for human skin odor determination; several techniques can be applied to collect, extract, transfer, and detect human skin odors. However, none of these methods are suitable for field sampling of a large number of individuals. Objective. The present study aimed to develop a simple, fast, non-invasive, and low-cost method for such a purpose. Methods. Considering that hair from legs can act as a retention mesh of volatile organic compounds (VOCs), samples of leg hairs provided by healthy adult males were collected and solid-phase microextraction (SPME), in headspace (HS) mode, coupled to gas chromatography (GC) and mass spectrometry (MS) analysis of the samples was carried out. A pilot test was applied to detect five quality markers that are frequently reported in human skin odors. Then, several steps were performed for method standardization. The method was applied to 36 different individuals (3 sampled under laboratory conditions and 33 under field conditions), aiming to evaluate its applicability in both environments. Findings. A total of 49 VOCs were identified, and 73.5% of these have been reported in previous studies. Main Conclusions. Hair from legs can be considered an efficient tool for human skin odor sampling and a suitable and practical matrix for human skin odor profile determination by using HS-SPME/GC-MS.

Energy trends and the water-energy binomium for Brazil.

According to the demands of energy saving and carbon emission reduction, the water vs. energy nexus has become a major concern worldwide. Brazil occupies a singular position in the global energy system. A major portion of the Brazilian occupancies has electricity and the energy system expansion that, at first, possesses adequate means for supporting the economic growing may experience some turnovers. The Brazil determination through alternative fuels was a natural choice, given its large hydropower potential and land agricultural base. In the transportation sector Brazil has developed its energy matrix towards an important rate of ethanol and biodiesel. Although those fuels are low carbon emitter, they may probably not be an affordable alternative regarding land use, food security and water footprint. In this way, considering the recent advances in the exploration of oil from Pre-salt (9-15 million barrels) and the discovery of shale gas wells up to 245 tcf, together to unfavorable social and environmental issues associated to biofuels, the Brazilian energy matrix might turn back to the fossil fuels again. These represent challenges to the Brazilian policymakers and how they will be solved will reflect not only in Brazil but also to the world at large.

Evaluation of PAH contamination in soil treated with solid by-products from shale pyrolysis.

The aim of this work was to evaluate the concentrations of polycyclic aromatic hydrocarbons (PAHs) in soils to which solid shale materials (SSMs) were added as soil conditioners. The SSMs were derived from the Petrosix pyrolysis process developed by Petrobras (Brazil). An improved ultrasonic agitation method was used to extract the PAHs from the solid samples (soils amended with SSMs), and the concentrations of the compounds were determined by gas chromatography coupled to mass spectrometry (GC-MS). The procedure provided satisfactory recoveries, detection limits, and quantification limits. The two-, three-, and four-ring PAHs were most prevalent, and the highest concentration was obtained for phenanthrene (978 ± 19 µg kg(-1) in a pyrolyzed shale sample). The use of phenanthrene/anthracene and fluoranthene/pyrene ratios revealed that the PAHs were derived from petrogenic rather than pyrogenic sources. The measured PAH concentrations did not exceed national or international limit values, suggesting that the use of SSMs as soil conditioners should not cause environmental damage.

Human health risk assessment of mercury in highly consumed fish in Salvador, Brazil.

This work reports assessing risks to human health resulting from mercury levels in sardines (Sardinella brasiliensis), which have been highly consumed by the low-income population from Salvador, Brazil. Mercury was determined using the Direct Mercury Analysis (DMA) in fifty-one commercially acquired samples in seventeen neighborhoods. The mercury content on a wet basis ranged from 0.023 to 0.083 µg g-1 for an average value of 0.039 µg g-1. The estimated weekly intake (EWI), target hazard quotient (THQ), and maximum safe consuming quantity (MSCQ) were used in the toxicological assessment, and all these indices denoted that this food does not pose any risks to the human health of the population that consumes it. The development of this work was very significant because most sardines sold in Salvador originate from Todos os Santos Bay, which has a history of mercury contamination.

Mercury in the Southwestern Atlantic reef-building coral Montastraea cavernosa (Cnidaria, Scleractinia).

Coastal ecosystems, such as coral reefs, are particularly vulnerable to mercury contamination due to direct contact with terrestrial sources. Here, we evaluated, for the first time, the concentration of mercury in coral reefs in the Southwestern Atlantic using the amphi-atlantic scleractinian coral Montastraea cavernosa. Sampling was realized over an extension of 200 km along different coral reefs. Our data show mercury values ranging from 0.01 to 0.27 mg kg-1 in the tissue and 0.001-0.06 mg kg-1 in the skeleton and higher values when compared to coral worldwide. The concentration of mercury in the tissue from Todos os Santos Bay was higher than in open sea regions but also higher compared to other coral reefs of the world, while the skeleton concentration did not indicate any differences when compared to the open sea regions. The data presented is of concern as we consider the importance of coral reefs and should be used in future environmental management planning.

Polycyclic aromatic hydrocarbons in coral reefs from Southwestern Atlantic: A seascape approach using tissue and skeleton of the coral Montastraea cavernosa (Cnidaria; Scleractinia).

Coastal marine ecosystems, such as coral reefs, are severely threatened by climate changes, overexploitation, and marine pollution. Particularly, environmental pollution caused by petroleum-derived substances is poorly studied in coral reefs in tropical developing countries, with a total absence of data about these contaminants in some regions. In this work, we determined the levels of conventional and unconventional PAHs in the tissue and skeleton of the coral Montastraea cavernosa in a seascape scale of the Southwest Atlantic. We sampled in 12 coral reefs adjacent to the coast along approximately 200 km. We found 14 PAHs, 2 Oxy-PAHs, and 15 Nitro-PAHs in the samples, and among them, benzo[a]pyrene, chrysene, benzo[a]anthracene, benzo[k]fluoranthene, indeno[1,2,3-c,d]pyrene and dibenz[a,h]anthracene, which are mutagenic, teratogenic and carcinogenic substances. Skeletons presented predominantly lower quantities of ∑PAHs than the respective tissue, except for the skeletons from one reef severely impacted by oil spills. The ∑PAHs levels were lower in a bay near an urbanized region than in open sea reefs. Diagnostic ratios indicate mixogenic sources, with the predominance of petrogenic origin. Our study provides the first occurrence of PAHs, Nitro-PAHs, and Oxy-PAHs distribution in corals from the Southwest Atlantic Ocean, and we expect that these data will help to evaluate any future impacts and management of this ecosystem.

Experimental study, simulation and technical-economic feasibility of an interesterification plant for hydrocarbons synthesis by using plastics and frying oil waste.

This work presents the experimental assessment of a 20 mL batch reactor's efficacy in converting plastic and oil residues into biofuels. The reactor, designed for ease of use, is heated using a metallic system. The experiments explore plastic solubilization at various temperatures and residence times, employing a mixture of distilled water and ethylene glycol as the solvent. Initial findings reveal that plastic solubilization requires a temperature of 350 °C with an ethylene glycol mole fraction of 0.35, whereas 250 °C suffices with a mole fraction of 0.58. Additionally, the study includes a process simulation of a plant utilizing a double fluidized bed gasifier and an economic evaluation of the interesterification/pyrolysis plant. Simulation results support project feasibility, estimating a total investment cost of approximately $12.99 million and annual operating expenses of around $17.98 million, with a projected payback period of about 5 years.

Volatile organic compounds obtained by in vitro callus cultivation of Plectranthus ornatus Codd. (Lamiaceae).

Plectranthus spp (Lamiaceae) are plants of economic importance because they are sources of aromatic essential oils and are also cultivated and several species of this genus are used as folk medicines. This paper describes the effects of different concentrations of the 2,4-dichlorophenoxyacetic acid (2,4-D) and 1-naphthaleneacetic acid (NAA) on the induction of callus from nodal segments of Plectranthus ornatus Codd and in the production of volatile organic compounds (monoterpenes and sesquiterpenes). The 20 and 40 day calli were subjected to solid phase micro extraction (HS-SPME) and submitted to GCMS analysis. Variations in VOCs between the samples were observed and, a direct relationship was observed between of the major constituent detected (α-terpinyl acetate) and the monoterpenes α-thujene, α-pinene, ß-pinene, camphene, sabinene and α-limonene that were present in the volatile fractions. Besides α-terpinyl acetate, isobornyl acetate and α-limonene were also major constituents. Variations were observed in VOCs in the analyzed periods. The best cultivation media for the production of VOCs was found to be MS0 (control). Moderate success was achieved by treatment with 2.68 µM and 5:37 µM NAA (Group 2). With 2,4-D (9.0 µM), only the presence of α-terpinyl acetate and isocumene were detected and, with 2.26 µM of 2,4-D was produced mainly α-terpinyl acetate, α-thujene and ß-caryophyllene (16.2%). The VOC profiles present in P. ornatus were interpreted using PCA and HCA. The results permitted us to determine the best cultivation media for VOC production and, the PCA and HCA analysis allowed us to recognize four groups among the different treatments from the compounds identified in this set of treatments.

The occurrence of pristine and functionalized fullerenes as constituents of airborne aerosols.

We investigated if pristine and functionalized fullerenes could be actual constituents of fine atmospheric aerosols. Comprehensive profiles of fullerenes from 1 µL extracts were made through matrix laser desorption ionization Time-of-Flight Mass Spectrometry (MALDI-MS) within a few minutes. The ion with m/z 720, corresponding to [C60]-•, was identified as fullerene after 1 µL of α-cyano-4-hydroxycinnamic acid matrix solution was spotted over the dried extracts. The ions with the m/z corresponding to C70, C76, C84, C100, C118, C128, and C130 were also attributed to other fullerene species detected within the samples. The ion m/z 878 was found to be the fullerene derivative diethyl methano[60]fullerene dicarboxylate. Since ions of fragmented fullerene molecules were not detected even at high laser energies, we considered the fullerenes' occurring as original constituents of real atmospheric particle matrices instead of being formed as artifacts of the laser action on samples. Therefore, this protocol would be helpful in the understanding of the distribution of either pristine or functionalized fullerenes in the environment and their participation in atmospheric chemistry under typical conditions, as well as its application in vitro and in vivo (eco)toxicity studies.

Polycyclic aromatic hydrocarbons in coral reefs with a focus on Scleractinian corals: A systematic overview.

The impact of petroleum exploitation and oil spills in marine ecosystems has increased over time. Among the concerns regarding these events, the impact on coral reefs stand out because this ecosystem has ecological and economic importance and is globally threatened. We performed a systematic review and bibliometric analysis of studies that determine polycyclic aromatic hydrocarbons (PAHs) in coral reefs, attempting to answer how the studies were distributed around the globe, the main environmental matrices and species of coral studied, the main PAHs found and their mean concentrations, and the methodology used. A bibliographic search resulted in 42 studies with worldwide distribution. The bibliometric results presented more explored terms, such as sediments and toxicology, and newly investigated terms, which should encourage a new area of study, such as those related to zooxanthellae and mucus. The main matrices studied in coral reefs are sediments, corals, and water, whereas air and other invertebrates have rarely been studied. Approximately 45 species of corals with several morphotypes have been reported. PAHs recommended by the United States Environmental Protection Agency (US EPA) were analyzed in all studies, while additional compounds were analyzed in only five. The methods used to determine hydrocarbons are predominantly the most traditional; however, for corals, studies have tended to separate tissue, zooxanthellae, skeleton, and mucus. In the future, we recommend investment in improving the capacity to detect non-conventional PAHs, more studies in regions that are rarely explored in developing countries, and the creation of databases to facilitate management planning on marine coasts.

Determination and evaluation of the ecological risk of mercury in different granulometric fractions of sediments from a public supply river in Brazil.

This work reports the quantification of total mercury in sediments collected in periods with and without rain from the Joanes River, Bahia, Brazil. Determinations were made using Direct Mercury Analysis (DMA), the accuracy of which was confirmed with two certified reference materials. The highest total mercury concentrations were found at the sampling point close to commercial areas and large residential condominiums. On the other hand, the lowest levels were found in the site close to a mangrove region. The geoaccumulation index was applied to the total mercury results, evidencing low contamination in the region studied. The contamination factor showed that of the seven stations investigated, four samples collected in the rainy season showed moderate contamination. The results of the ecological risk assessment were utterly consistent with the contamination factor data. This study showed that the smaller sediment particles concentrate more mercury, corroborating what has been predicted by the adsorption processes.

Particle emission from heavy-duty engine fuelled with blended diesel and biodiesel.

In this study, particulate matter (PM) were characterized from a place impacted by heavy-duty vehicles (Bus Station) fuelled with diesel/biodiesel fuel blend (B3) in the city of Londrina, Brazil. Sixteen priority polycyclic aromatic hydrocarbons (PAH) concentrations were analyzed in the samples by their association with atmospheric PM, mass size distributions and major ions (fluorite, chloride, bromide, nitrate, phosphate, sulfate, nitrite, oxalate; fumarate, formate, succinate and acetate; lithium, sodium, potassium, magnesium, calcium and ammonium). Results indicate that major ions represented 21.2% particulate matter mass. Nitrate, sulfate, and ammonium, respectively, presented the highest concentration levels, indicating that biodiesel may also be a significant source for these ions, especially nitrate. Dibenzo[a,h]anthracene and indeno[1,2,3,-cd]pyrene were the main PAH found, and a higher fraction of PAH particles was found in diameters lower than 0.25 µm in Londrina bus station. The fine and ultrafine particles were dominant among the PM evaluated, suggesting that biodiesel decreases the total PAH emission. However, it does also increase the fraction of fine and ultrafine particles when compared to diesel.

Method development using chemometric tools for determination of endocrine-disrupting chemicals in bottled mineral waters.

A simple method was developed to determine 14 endocrine-disrupting chemicals (EDCs) in bottled waters, based on dispersive micro-solid phase extraction (d-µ-SPE) and liquid chromatography-mass spectrometry (LC-MS). Extraction was optimized using 2 k-1 factorial and Doehlert experimental designs. Optimized conditions were 80 mg C18, 25 min extraction at 1000 rpm, and 6 min desorption time. Repeatability was below 17 % for all EDCs. LOD and LOQ varied from 1.60 ng L-1 (estradiol, E2) to 23.2 ng L-1 (dimethylphthalate, DMP) and from 5.33 ng L-1 (E2) to 77.3 ng L-1 (DMP). We found DMP and bisphenol A (BPA) in samples after the heat treatment. DMP was up to 58.7 µg L-1, while BPA was up to 1.34 µg L-1. Tolerance of daily intake (TDI) for DMP were 2.50-2.94 µg kg-1 day-1 (children) and 1.43-1.68 µg kg-1 day-1 (adults). TDI for BPA were 0.03-0.07 µg kg-1 day-1 (children) and 0.01-0.04 µg kg-1 day-1 (adults).

Occurrence of mercury in polychaete species (Annelida) and their associated sediments from an important Southern Atlantic Ocean Bay.

In the present study, the Hg levels in freshly collected polychaete species and their associated sediments were evaluated from Todos os Santos Bay, Northeastern Brazil. Additionally, it was also measured the Hg distribution along the annelids' body parts (anterior region, abdomen, and posterior region). Total Hg concentration was as follows: 13.6-144 µg kg-1 (Scolelepis chilensis, deposit feeder), 8.2-122 µg kg-1 (Laeonereis acuta, deposit feeder), 95-612 µg kg-1 (Armandia agilis, deposit feeder); 96.6-206 µg kg-1 (Lumbrineris sp., carnivorous), 75.3-112 µg kg-1 (Goniada echinulate, carnivorous), and 115-198 µg kg-1 (Branchiomma sp., suspension feeder). In turn, Hg levels in sediments ranged from 2.77 ± 0.24 to 6.38 ± 0.15 µg kg-1. Hg concentrations found in polychaete soft tissues were higher than those found in the sediments. Specific habits, feeding behavior, trophic level, and stressful environmental conditions are the main factors affecting the Hg levels in the species studied. The bioaccumulation factor (BAF), contamination factor (CF), and ecological risk assessment (Er) were calculated. The BAF values were higher than 1 for all studied species, indicating Hg bioaccumulation in the annelids, but the low levels of CF e Er showed those Hg levels present low to no significant ecological risk for the biota and benthonic organisms living in the sediments. Finally, no statistically significant difference was observed for Hg concentration levels along the polychaete body parts.

Customized dispersive micro-solid-phase extraction device combined with micro-desorption for the simultaneous determination of 39 multiclass pesticides in environmental water samples.

A dispersive micro-solid phase extraction (d-µ-SPE) procedure was developed for the simultaneous extraction of 39 multiclass pesticides, containing a variety of chemical groups (organophosphate, organochlorine, pyrethroid, strobilurin, thiocarbamate, triazole, imidazole, and triazine), from water samples. A customized d-µ-SPE glass device was combined with a multi-tube platform vortex and a micro-desorption unit (Whatman Mini-UniPrep G2 syringeless filter), which allowed the unique simultaneous desorption, extract filtration, and injection. A simplex-centroid mixture design and Doehlert design were employed to optimize the extraction conditions. The optimized extraction conditions consisted of an extraction time of 30 min, an addition of 6.74 % of NaCl into 100 mL of water sample, and a desorption time of 24 min with 500 µL of EtAc. The procedure provided a low limit of detection (LOD), ranging from 0.51 ng L-1 (4,4-DDE) to 22.4 ng L-1 (dimethoate), and an enrichment factor ranging from 72.5 (dimethoate) to 200 (tebuconazole). The relative recoveries of the pesticides from spiked freshwater and seawater ranged from 74.2 % (endrin) to 123 % (molinate). The proposed procedure was applied to detect the presence of multiclass pesticides in environmental water samples. Three pesticides commonly applied in Brazil, namely, malathion, dimethoate, and lambda-cyhalothrin, were detected in concentrations ranging from

Microplastic pollution in Southern Atlantic marine waters: Review of current trends, sources, and perspectives.

Microplastics (MPs) are emerging and ubiquitous contaminants which have been gaining prominence since the last decade to nowadays. This is due to their possible adverse effects in aquatic ecosystems as well as the huge amount of plastic waste exponentially generated around the globe. Plastics may be introduced either directly to water bodies or indirectly to the aquatic systems by being carried by the wind, from emissions of contaminated effluents, and soil leaching, among other processes. In turn, these debris may interact with organic and inorganic contaminants, such as polycyclic aromatic hydrocarbons (PAHs), polybrominated diphenyl ethers (PBDEs) and trace constituents, and with microorganisms. Although the abundance of microplastics from South Atlantic waters is among the highest found worldwide, the number of studies in these marine waters regarding MP contamination is still scarce. Additionally, there still are no consensus on the best sampling conditions, which may be underestimating MPs. In this way, adequate MPs studies regarding their distribution, exposure levels, chemical and biological interactions are highly suggested in order to better understand both environmental and human health potential risks. This review assessed advances in sampling, analytical methodologies, characterization and understanding of MP sources in these marine waters in comparison to data from other regions around the globe.

Exploratory analysis of the presence of 14 carbonyl compounds in bottled mineral water in polyethylene terephthalate (PET) containers.

Carbonyl compounds (CCs) can migrate from bottles to mineral water because of plastic degradation. An exploratory analysis of the presence a significant number of CCs (14) in bottled mineral water with and without gas in polyethylene terephthalate (PET) containers was performed using ultra-fast liquid chromatography coupled to mass spectrometry (UFLC-MS). The data from the analysis was submitted to chemometric treatment (principal component analysis, PCA). Formaldehyde, acetaldehyde, and benzaldehyde were found in all samples (0.07-125 ng mL-1). Acrolein and acetone were present in 81% and 75% of the samples, respectively. The concentration of acrolein in carbonated water was up to 3.8 times greater than that measured in non-carbonated water (0.07-0.44 ± 0.01 ng mL-1). PCA analysis showed that gasification can influence the composition of CCs present in mineral water and that the plastic material of the bottles is a likely source of CCs. In addition, benzaldehyde levels may be associated with the use of recycled materials.

Occurrence of 3-nitrobenzanthrone and other powerful mutagenic polycyclic aromatic compounds in living organisms: polychaetes.

In this work we report the occurrence of powerful mutagenic 3-nitrobenzanthrone (3-NBA), in addition to 18 polycyclic aromatic hydrocarbons (PAHs), 6 oxygenated PAHs and 27 nitrated PAHs in polychaete worms. Benzanthrone (BA), another important mutagenic polycyclic aromatic compound (PAC) also was detected in the samples. Polychaete annelids have great ecological relevance, being widely distributed in different environmental conditions, from intertidal zones up to seven thousand feet deep areas. They are abundantly found in both contaminated and uncontaminated areas and, therefore, used as indicators of the pollution status of a given area. As we know, so far, most of these PACs has not been previously reported in living organisms before. The 3-NBA concentrations determined in this study were within 0.11-5.18 µg g-1. Other relevant PACs such as PAHs, quinones and nitro-PAHs were found in maximum concentrations at 0.013 µg g-1 (coronene) to 11.1 µg g-1 (benzo[k]fluoranthene), 0.823 µg g-1 (9,10-phenenthrenequinone) to 12.1 µg g-1 (1,4-benzoquinone) and 0.434 (1-nitronaphthalene) µg g-1 to 19.2 µg g-1 (6-nitrobenzo[a]pyrene), respectively. Principal component analysis (PCA), ternary correlations and diagnostic ratios were employed in order to propose probable sources for PACs. Although statistical analysis preliminarily has indicated both pyrogenic and petrogenic contributions, petrogenic sources were predominant reflecting the impacts of petroleum exploration and intensive traffic of boats in the study area.

Determination of free- and bound-carbonyl compounds in airborne particles by ultra-fast liquid chromatography coupled to mass spectrometry.

This study presents the development and application of a new analytical methodology for determination of free- and bound-carbonyl compounds (CC) (as the CC themselves and as the hydroxyalkylsulfonic acids - HASA, respectively) in airborne particles. Free- and bound-CC determination were done through reaction with 2,4-dinitrophenylhydrazine (2,4-DNPH) and analysis by UFLC-MS. The method was successfully validated, showing good figures for linearity (R2 ≥ 0.9937), sensibility (3 fg ˂ LOD ˂ 20 fg for methacrolein and heptanal, respectively) and repeatability (5.9% ˂ RSD ˂ 13%). The proposed method was successfully applied in real samples of inhalable atmospheric particulate matter (PM10) and urban dust certified reference material (SRM 1649 b). The main CC determined in the SRM 1649 b was formaldehyde (75.4 µg g-1 in the free form, and 1898 µg g-1 in the bound form). In addition, for the bound-CC form (HASA), concentrations were determined for acetaldehyde (60.3 µg g-1), acetone (20.5 µg g-1), acrolein (9.15 µg g-1), propionaldehyde (17.1 µg g-1) and valeraldehyde (12.2 µg g-1). For PM10 samples, formaldehyde (148 µg g-1) and acetaldehyde (28.9 µg g-1) were quantified as free aldehydes and as HASA (hydroxymethanelsulfonic acid and hydroxyethanesulfonic acid were 432 µg g-1 and 211 µg g-1, respectively). Other bound-CC were, on average, within 19.2 µg g-1 (acrolein) and 62.1 µg g-1 (valeraldehyde). For all samples, acetone, acrolein, propionaldehyde and valeraldehyde were quantified only as HASA (bound-CC). Therefore, we could identify and quantify six carbonyl compounds using the proposed method. It is worth mentioning the hydrolysis step was crucial for the correct quantification of the HASAs. This was, in turn, what enabled the quantification of a greater number of analytes in the airborne samples. Hence, this procedure was found to be comprehensive, precise, accurate and suitable to be employed for determination of free-CC and HASA (bound-CC) in atmospheric particulate samples.

A liquid chromatographic method optimization for the assessment of low and high molar mass carbonyl compounds in wines.

Carbonyl compounds (CC) play an important role in beverage aroma since they may affect flavor of wines, brandies, and beers, among others. For this reason, it is necessary to identify and quantify CC through adequate analytical techniques. This study is a proposal of both developing and optimization of a new analytical methodology that allows investigate C(1)-C(8 )CC in wines simultaneously by quantifying even those ones that are predominantly present in the adduct form hydroxylalkylsulfonic acids (HASA). The HASA dissociation is undertaken by specific alkaline media (pH 11). The developed methodology employed the LC with UV/VIS detection (lambda = 365 nm) technique under gradient elution in the way to reach both free-CC and bound-CC quantification. Results showed that binary gradient system using eluent A (MeOH/ACN/H(2)O 74.5:0.5:25% v/v/v) and eluent B (MeOH) reached the best separation condition of both lower and higher molecular mass CC. This proposed method allowed simultaneous quantification of formaldehyde, acetaldehyde, propanone, furfuraldehyde, butyraldehyde, benzaldehyde, hexanaldehyde, 2-ethyl-hexanaldehyde, E-pent-2-en-1-al, and cyclohexanone--all of them were found in white wine (Moscato Canelli) and red wine (Shiraz) produced in the São Francisco Valley, in the Northeastern Region of Brazil--although this optimized method may probably be suitable for quantification of propionaldehyde, isobutyraldehyde, heptanaldehyde, octanaldehyde, benzaldehyde, and E-hex-2-en-1-al as well. We could not prove if this method is also able to determine the latter CC group since we have not found these substances present in detectable levels in our real samples considered in this study.