Investigation of an individual with background levels of exhaled isoprene: a case study

Isoprene is one of the most abundant and most frequently evaluated volatile organic compounds in exhaled breath. Recently, several individuals with background levels of exhaled isoprene have been identified. Here, case study data are provided for an individual, identified from a previous study, with this low prevalence phenotype. It is hypothesized that the individual will illustrate low levels of exhaled isoprene at rest and during exercise. At rest, the subject (7.1 ppb) shows background ( μ = 14.2 ± 7.0 ppb) levels of exhaled isoprene while the control group illustrates significantly higher quantities (μ = 266.2 ± 72.3 ppb) via proton transfer reaction mass spectrometry (PTR-MS). The result, background levels of isoprene at rest, is verified by thermal desorption gas chromatograp hy mass spectrometry (TD-GC-MS) collections with the individual showing −3.6 ppb exhaled isoprene while the room background contained μ= −4.1 ± 0.1 ppb isoprene. As isoprene has been shown previously to increase at the initiation of exercise, exercise bike experiments were performed with the i ndividual identified with low isoprene, yielding low and invariant levels of exhaled isoprene (μ = 6.6 ± 0.1 ppb) during the exercise while control subjects illustrated an approximate 2.5-fold increase (pre μ = 286.3 ± 43.8 ppb, exercise μ = 573.0 ± 147.8 ppb) in exhaled isoprene upon exercise start. Additionally, exhaled breath bag data showed a significant decrease in isoprene (delta post/p...
Source: Journal of Breath Research - Category: Respiratory Medicine Authors: Source Type: research