Analysis of breath, exhaled via the mouth and nose, and the air in the oral cavity

Abstract

Analyses have been performed, using on-line selected ion flow tube mass spectrometry (SIFT-MS), of the breath of three healthy volunteers, as exhaled via the mouth and the nose and also of the air in the oral cavity during breath hold, each morning over a period of one month. Nine trace compounds have been quantified and concentration distributions have been constructed. Of these compounds, the levels of acetone, methanol and isoprene are the same in the mouth-exhaled and the nose-exhaled breath; hence, we deduce that these compounds are totally systemic. The levels of ammonia, ethanol and hydrogen cyanide are much lower in the nose-exhaled breath than in the mouth-exhaled breath and highest in the oral cavity, indicating that these compounds are largely generated in the mouth with little being released at the alveolar interface. Using the same ideas, both the low levels of propanol and acetaldehyde in mouth-exhaled breath appear to have both oral and systemic components. Formaldehyde is at levels in mouth- and nose-exhaled breath and the oral cavity that are lower than that of the ambient air and so its origin is difficult to ascertain, but it appears to be partially systemic. These results indicate that serious contamination of alveolar breath exhaled via the mouth can occur and if breath analysis is to be used to diagnose metabolic disease then analyses should be carried out of both mouth- and nose-exhaled breath to identify the major sources of particular trace compounds.

Quantitative Analysis of VOCs in Exhaled Breath from Asian Volunteers: A Pilot Study

“…A study reported by Turner et al found high inter-individual variations in breath concentrations of acetone with mean values ranging from 148 to 2744 ppb (Caucasian volunteers) [40] . Wang et al, also reported similar intra and inter individual variations in breath acetone concentrations (a mean value of 636 ppb; three volunteers monitored over a period of 30 days) [41]. These variations in acetone concentrations are not unusual as breath acetone is entirely systemic in origin [42].…”

“…Concentrations for acetaldehyde (39.6-46.2 ppb) observed in the present study are also similar to the concentrations observed in the literature reports. Literature reports are mainly based on breath examination of Caucasian populations [41,47], which could explain the differences observed in the breath concentrations of certain VOCs.…”

Changes in oral trace gas concentrations following orthognathic surgery and intermaxillary fixation: a case study using selected ion flow tube mass spectrometry

“…The sampling flow was reduced to the desired rate using a short length of 1/16 inch PTFE tubing which possessed an internal diameter of 0.007 inch [9]. The compounds of interest (sulphides, organic acids, ammonia, isoprene and acetone) were quantified by monitoring the specific ion product of the reaction between the compound of interest and the precursor ion transformed into absolute concentrations using a predetermined reaction rate coefficient [6][7][11][12][13][14] . Precursor ion count rates for all ions exceeded 800 000 cps, with precursor ion purity exceeding 98.5%.…”

“…Specifically, bacteria present in the mouth, in particular the dorsal surface of the tongue, catabolise food stuffs to produce a variety of chemicals, some of which result in little odour at typical concentrations, such as ammonia [6], while others are a source of malodour [5]. The predominant odiferous compounds derive from sulphur-containing amino acids and include hydrogen sulphide (H 2 S), methylmercaptan (CH 3 SH), dimethylsulphide (CH 3 SCH 3 ), and dimethyldisulphide (CH 3 S 2 CH 3 ), although additional compounds such as short-chain organic acids (butyric, propionic and valeric), polyamines and indole may also contribute [5].…”

Pseudomonas aeruginosaand cyanide production

“…Conversely, cyanide is absent from the sputum of bronchiectasis patients without P. aeruginosa infection [5,6] and HCN is very low or absent from the breath of healthy children [8]. Studies in healthy adults have shown that much of the HCN is generated in the mouth and this could have importance when measuring HCN in exhaled breath in relation to infection with P. aeruginosa [9].…”