Screening for volatile biomarkers of colorectal cancer by analyzing breath and fecal samples using thermal desorption combined with GC-MS (TD-GC-MS).

Breath and fecal VOCs, among others, represent a new and encouraging clinical practice for the differential diagnosis of CRC. The purpose of our research was to identify VOCs present in exhaled air and feces of 20 HVs and 15 CRC patients. For collection of gas phase released from feces, emission microchambers were applied. Sorption tubes were used to enrich analytes for both breath and fecal samples. TD technique combined with GC-MS was used at the separation and identification step. The combination of statistical methods was used to evaluate the ability of VOCs to classify control group and CRC patients. Heptanoic acid, acetone, 2,6,10-trimethyldodecane, n-hexane, skatole, and dimethyl trisulfide are observed in elevated amounts in the patients group. The performance of diagnostic models on the tested data set was above 90%. This study is the first attempt to document the using of TD-GC-MS to analyze both breath and fecal samples to search for volatile biomarkers of CRC. A full evaluation of the results described herein requires further studies involving a larger number of samples. Moreover, it is particularly important to understand the metabolic pathways of substances postulated as tumor biomarkers.

Identification of novel halogenated naturally occurring compounds in marine biota by high-resolution mass spectrometry and combined screening approaches.

Marine animals, plants or bacteria are a source of bioactive naturally-occurring halogenated compounds (NHCs) such as bromophenols (BPs), bromoanisoles (BAs) and hydroxylated or methoxylated analogues of polybrominated diphenyl ethers (HO-PBDEs, MeO-PBDEs) and bromobiphenyls (HO-BBs, MeO-BBs). This study applied a comprehensive screening approach using liquid chromatography high-resolution mass spectrometry and combining target, suspect and non-target screening with the aim to identify new hydroxylated NHCs which might be missed by commonly applied gas chromatographic methods. 24 alga samples, 4 sea sponge samples and 7 samples of other invertebrates were screened. Target screening was based on 19 available reference standards of BPs, (di)OH-BDEs and diOH-BBs and yielded seven unequivocally identified compounds. 6-OH-BDE47 was the most frequently detected compound with a detection frequency of 31%. Suspect screening yielded two additional compounds identified in alga samples as well as 17 and 8 compounds identified in sea sponge samples of Lamellodysidea sp. and Callyspongia sp., respectively. The suspect screening results presented here confirmed the findings of previous studies conducted on sea sponge samples of Lamellodysidea sp. and Callyspongia sp. Additionally, in Lamellodysidea sp. and Callyspongia sp. 13 and 4 newly identified NHCs are reported including heptabrominated diOH-BDE, monochlorinated pentabrominated diOH-BDE, hexabrominated OH-MeO-BDE and others. Non-target screening allowed the identification of 31 and 20 polyhalogenated compounds in Lamellodysidea sp. and Callyspongia sp. samples, respectively. Based on the obtained fragmentation spectra, polybrominated dihydroxylated diphenoxybenzenes (diOH-PBDPBs), such as hepta-, octa- and nonabrominated diOH-BDPBs, could be identified in both species. To our knowledge, this study is the first report on the environmental presence of OH-PBDPBs.

Matrix solid-phase dispersion (MSPD) as simple and useful sample preparation technique for determination of polybrominated diphenyl ethers (PBDEs) in dust.

In the present study a novel analytical procedure for the determination of polybrominated diphenyl ethers in dust samples was developed. The main aim of the research was the selection of the optimum conditions of the matrix solid-phase dispersion before the final determination of polybrominated diphenyl ethers in dust samples. In order to assess the best usefulness of this technique, a favourable ratio of sample amount to the mass of dispersing sorbent, as well as the type of this sorbent used has been tested. The type of sorbent responsible for additional purification (clean-up sorbent) of the extract during matrix solid-phase dispersion was also selected. Gas chromatography coupled with mass spectrometry will be used at the final determination step. Preliminary results indicate that the use of matrix solid-phase dispersion can be a promising alternative to other time-consuming and multi-stage analytical procedures. The proposed method provided satisfactory recoveries (76-119%) and limits of detection: 2.1-4.4 pg µL-1 for tri-heptaBDE in linear range of 5-100 pg µL-1; 480 pg µL-1 for decaBDE in linear range of 500-2000 pg µL-1 from only 0.05 g of a dust sample. Finally, the method was applied to study the content of selected polybrominated diphenyl ethers in real dust samples. Some polybrominated diphenyl ether congeners reached up to (16.3 ±â€¯3.0)·102 ng g-1.

Indoor air quality of everyday use spaces dedicated to specific purposes-a review.

According to literature data, some of the main factors which significantly affect the quality of the indoor environment in residential households or apartments are human activities such as cooking, smoking, cleaning, and indoor exercising. The paper presents a literature overview related to air quality in everyday use spaces dedicated to specific purposes which are integral parts of residential buildings, such as kitchens, basements, and individual garages. Some aspects of air quality in large-scale car parks, as a specific type of indoor environment, are also discussed. All those areas are characterized by relatively short time use. On the other hand, high and very high concentration levels of xenobiotics can be observed, resulting in higher exposure risk. The main compounds or group of chemical compounds are presented and discussed. The main factors influencing the type and amount of chemical pollutants present in the air of such areas are indicated.

Indoor air quality in public utility environments-a review.

Indoor air quality has been the object of interest for scientists and specialists from the fields of science such as chemistry, medicine and ventilation system design. This results from a considerable number of potential factors, which may influence the quality of the broadly understood indoor air in a negative way. Poor quality of indoor air in various types of public utility buildings may significantly affect an increase in the incidence of various types of civilisation diseases. This paper presents information about a broad spectrum of chemical compounds that were identified and determined in the indoor environment of various types of public utility rooms such as churches, museums, libraries, temples and hospitals. An analysis of literature data allowed for identification of the most important transport paths of chemical compounds that significantly influence the quality of the indoor environment and thus the comfort of living and the health of persons staying in it.

Concentrations of monoaromatic hydrocarbons in the air of the underground car park and individual garages attached to residential buildings.

The paper describes the characteristics of a two-level underground car park and three individual garages attached to residential buildings, differing by the resident utilization habits, located in North Poland (Tri-City agglomeration area). The strategy of collecting the analyte samples from air in mentioned enclosed areas, concerning the determination of benzene, toluene, ethylbenzene, o-xylene and p,m-xylenes (BTEX) concentrations was performed using passive sampling technique - Radiello® diffusive passive samplers with graphitised charcoal cartridge as a sorption medium. The stage of liberation and final determination of collected analytes was conducted with the use of thermal desorption-gas chromatography-flame ionisation detector (TD-GC-FID) system. As a result of the performed measurements in two-level underground car park, it was observed that the time-weighted average concentrations of BTEX in air were as follows: Level-1 - benzene - 5.2±1.1µg/m3, toluene - 12.3±2.4µg/m3, ethylbenzene 2.85±0.80µg/m3, o-xylene - 4.6±1.4µg/m3, p, m-xylenes - 8.8±2,4µg/m3; Level-2 - benzene - 5.2±1.1µg/m3, toluene - 12.9±3.6µg/m3, ethylbenzene - 2.73±0.79µg/m3, o-xylene - 4.2±1.1µg/m3, p, m-xylenes - 8.5±2.3µg/m3. As for residential garages, the time-weighted average concentrations of BTEX in air were in the following ranges: from 5.9 to 53µg/m3 (benzene), from 7.1 to 195µg/m3 (toluene), from 3.0 to 39µg/m3 (ethylbenzene), from 5.6 to 44µg/m3 (o-xylene) and from 6.3 to 99µg/m3 (p,m-xylenes). Also, BTEX concentration ratios such as: tol/benz ratio and (m, p)-xyl/et.benz coefficient, were calculated based on the obtained results to assess the "freshness" of air mass and the influence exerted by vehicle movement on the concentration of BTEX in air in studied enclosed areas.