Article

Volatile metabolites in the exhaled breath of healthy volunteers: their levels and distributions.

Institute for Science and Technology in Medicine, School of Medicine, Keele University, Thornburrow Drive, Hartshill, Stoke-on-Trent ST4 7QB, UK.
Journal of Breath Research (impact factor: 2.54). 09/2007; 1(1):014004. DOI:10.1088/1752-7155/1/1/014004 pp.014004
Source: PubMed

ABSTRACT The data obtained for the concentration distributions of the most abundant volatile metabolites in exhaled breath determined in two independent studies are reviewed, the first limited study involving five healthy volunteers providing daily breath samples over a month, and the subsequent study involving 30 healthy volunteers providing breath samples weekly over six months. Both studies were carried out using selected ion flow tube mass spectrometry, SIFT-MS, to obtain on-line, real-time analyses of single breath exhalations, avoiding the complications associated with sample collection. The distributions of the metabolites from the larger more comprehensive study are mostly seen to be log normal with the median values (in parts per billion, ppb) being ammonia (833), acetone (477), methanol (461), ethanol (112), propanol (18), acetaldehyde (22), isoprene (106) with the geometric standard deviation being typically 1.6, except for ethanol which was larger (3.24) due to the obvious increase of breath ethanol following the ingestion of sugar. These were the first well-defined concentration distributions of breath metabolites obtained and they are the essential requirement for recognizing abnormally high levels that are associated with particular diseases. The associations of each metabolite with known diseased states are alluded to. These SIFT-MS studies reveal the promise of breath analysis as a valuable addition to the tools for clinical diagnosis and therapeutic monitoring.

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Keywords

30 healthy volunteers
 
breath ethanol
 
breath samples
 
breath samples weekly
 
comprehensive study
 
concentration distributions
 
exhaled breath
 
first limited study
 
first well-defined concentration distributions
 
geometric standard deviation
 
healthy volunteers
 
independent studies
 
ion flow tube mass spectrometry
 
particular diseases
 
real-time analyses
 
sample collection
 
SIFT-MS studies
 
single breath exhalations
 
subsequent study
 
therapeutic monitoring