Isoprene levels in the exhaled breath of 200 healthy pupils within the age range 7–18 years studied using SIFT-MS

Abstract

The published results of breath isoprene studies, to date largely involving adults, are briefly reviewed with special attention given to the work done on this topic during the last 10 years using selected ion flow tube mass spectrometry, SIFT-MS. Then the new data recently obtained on isoprene levels in the exhaled breath of some 200 healthy children and young adults (pupils) with ages ranging from 7 to 18 years measured using SIFT-MS are presented in detail. A concentration distribution has been constructed from the data obtained and compared to that for healthy adults also obtained from SIFT-MS data. Although there is overlap between the two distributions, which are close to log normal in both cases, the median level for the young cohort is much lower at 37 parts-per-billion, pbb, geometric standard deviation, GSD, 2.5, compared to that for the adult cohort of 106 ppb with a GSD of 1.65. Further to this, there is a clear increase in the mean breath isoprene concentration with age for the young cohort with a doubling of the level about every 5-6 years until it reaches the age-invariant mean level of that for adult cohort. Should this trend be extrapolated downwards in age it would indicate a near-zero breath isoprene in the newborn that was indicated by a previous study. Indeed, in the present study isoprene was not detected on the breath of two young children. The results reveal mean breath isoprene levels (±SD) for pupils within the given age ranges as 7-10 years (28 ± 24 ppb), 10-13 years (40 ± 21 ppb), 13-16 years (60 ± 41 ppb) and 16-19 years (54 ± 31 ppb). The more rapid increase that occurs between the second and third age ranges is statistically highly significant (p = 0.001) and we attribute this phenomenon to the onset of puberty and the spurt in growth that occurs during this phase of development. There is no significant difference in mean breath isoprene between males and females for both the adult cohort and the younger cohort.

Differentiation of chronic obstructive pulmonary disease (COPD) including lung cancer from healthy control group by breath analysis using ion mobility spectrometry

“…Recently, some studies have identified groups of volatiles and other biomarkers in COPD patients that have potentially useful relationships to cell degradation processes. There are several analytical detection approaches available, including gas chromatography-mass spectrometry (GC-MS) [1][2][3][4][5][6][7], proton transfer reaction-mass spectrometry (PTR-MS) [8][9][10][11], selected ion flow tube-mass spectrometry (SIFT-MS) [12][13][14][15][16][17][18], ion mobility spectrometry (IMS) [2,[19][20][21][22][23][24][25][26][27][28], and electronic noses [29][30][31][32][33] as well as other types of sensors [34][35][36][37][38][39][40].…”

One-year time series of investigations of analytes within human breath using ion mobility spectrometry

“…There are several analytical detection approaches available for human breath investigations, including gas chromatographymass spectrometry (GC-MS) [1][2][3][4][5][6][7], proton transfer reactionmass spectrometry (PTR-MS) [8][9][10][11], selected ion flow tubemass spectrometry (SIFT-MS) [12][13][14][15][16][17][18] and ion mobility spectrometry (IMS) [2,[19][20][21][22][23][24][25][26][27][28] and electronic noses [29][30][31][32][33] and different types of sensors [34][35][36][37][38][39][40]. The sampling techniques include direct sampling, partly using sample loops [41][42][43][44], Tedlar bags [45][46][47]…”

Physiological Modeling for Analysis of Exhaled Breath

“…Using an analogous line of argument, exercise scenarios on an ergometer support the idea that some peripheral (muscle) tissue may play a role in isoprene synthesis. While this contrasts previous work postulating a purely hepatic origin of isoprene [15,50], the above modeling study provides interesting new perspectives on the age dependence of isoprene output [49,47,34] as well as its reduction under statin therapy [24,50]. Furthermore, it opens up the possibility for a mechanistic interpretation of future experimental findings and challenges new hypotheses.…”