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In recent years, the use of electronic cigarettes (e-cigs) has increased. However, their long-term effects on oral health and saliva remain poorly understood. Therefore, this study aimed to evaluate the saliva of e-cig users and investigate possible biomarkers. Participants were divided into two groups: the Electronic Cigarette Group (EG)—25 regular and exclusive e-cig users—and Control Group (CG)—25 non-smokers and non-e-cig users, matched in sex and age to the EG. The clinical analysis included the following parameters: age, sex, heart rate, oximetry, capillary blood glucose, carbon monoxide (CO) concentration in exhaled air, and alcohol use disorder identification test (AUDIT). Qualitative and quantitative analyses of saliva included sialometry, viscosity, pH, and cotinine concentrations. Furthermore, the EG and CG salivary metabolomes were compared using gas chromatography coupled with mass spectrometry (GC-MS). Data were analyzed using the Mann–Whitney test. The MetaboAnalyst 6.0 software was used for statistical analysis and biomarker evaluation. The EG showed high means for exhaled CO concentration and AUDIT but lower means for oximetry and salivary viscosity. Furthermore, 10 metabolites (isoleucine, 2-hydroxyglutaric acid, 3-phenyl-lactic acid, linoleic acid, 3-hydroxybutyric acid, 1,6-anhydroglucose, glucuronic acid, valine, stearic acid, and elaidic acid) were abundant in EG but absent in CG. It was concluded that e-cig users had high rates of alcohol consumption and experienced significant impacts on their general health, including increased cotinine and CO concentration in exhaled air, decreased oximetry, and low salivary viscosity. Furthermore, they showed a notable increase in salivary metabolites, especially those related to inflammation, xenobiotic metabolism, and biomass-burning pathways. [ABSTRACT FROM AUTHOR]

A new MIMS-derived technique, headspace membrane introduction mass spectrometry (HS-MIMS), is described for direct trace level analysis of volatile organic compounds (VOCs) in soil and other dry or wet solid matrixes. A silicone membrane interface is placed about 15 cm from the ion source, and a closed airspace (headspace) is created by connecting a toggle valve to the 1/4 in. tubing that connects the membrane interface to the ion source. For the VOC analysis, the headspace is evacuated and the solid sample vessel is heated to 90 degrees C. The VOCs are rapidly desorbed from the sample, pervaporated through the membrane, and preconcentrated for 4 min in the evacuated headspace. Then, the toggle valve is opened and the trapped VOCs are released into the ion source region of a quadrupole mass spectrometer. By electron ionization and selected-ion monitoring, a relatively sharp and intense peak is obtained and used for quantification. The HS-MIMS analysis shows excellent linearity and reproducibility and detection limits for many VOCs typically of 50-100 ng/kg (ppt).

Aims: To gather data on agricultural practices in organic farms in Sao Paulo, Brazil, and evaluate their relationship with the microbiological characteristics of samples collected along the production chain. Methods and Results: Practices data were based on field observations and interviews with farmers in 10 selected organic lettuce producing farms. Counts of Enterobacteriaceae and surveys for Salmonella were performed in samples of lettuce (before and after washing), fertilizers, irrigation and washing water, all collected in the same farm. Water samples were also tested for total coliforms and generic Escherichia coli. Isolated Enterobacteriaceae were identified by MALDI‐TOF MS. Contamination of lettuce was influenced by some agricultural practices: chicken manure‐based fertilization resulted in higher Enterobacteriaceae counts in lettuce when compared to other types of manure, whereas pre‐washed lettuces presented lower microbial counts than non‐pre‐washed samples. Salmonella was detected in one lettuce sample by qPCR. Escherichia coli was detected in all irrigation water samples. All sample types contained Enterobacteriaceae species commonly reported as opportunistic human pathogens. Conclusions: The data highlight the need for improvement in the good agricultural practices in the studied farms. Significance and Impact of the Study: This study provides information on agricultural practices and microbiological characteristics of organic lettuce, contributing to the development of more accurate risk assessments. [ABSTRACT FROM AUTHOR]

Ion/molecule reactions of neutral ozone with positive ions and halogen cations were studied in the gas phase by double- and triple-stage pentaquadrupole mass spectrometry. Neutral ozone was found to easily transport an oxygen atom to a number of positive ions in a novel gas-phase oxidation reaction that produces the ionized N-oxide derivatives as the main ionic products.

A systematic investigation was conducted on the gas-phase reactivity of the singly charged sulfur hexafluoride fragment ions SFn+ (n = 0-5) and the doubly charged ions 32SFn2+ (n = 2.4) with O2 and the common oxygenated netural gases, H2O, CO, CO2 and N2O. Whereas the higher homologues and the doubly charged ions undergo mainly charge exchange or dissociation by F loss, novel reactions were observed for the lower homologues SF+ and S+. It is likely that the ease of dissociation of SF4+ will prevent most of its associative reactions.