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J Balmes

Publications and source records attributed to J Balmes.

42 records · Page 3Linked to original sources
PubMedDate not supplied

Measurement of nasal irritant sensitivity to pulsed carbon dioxide: a pilot study.

Nasal irritation and associated symptoms (e.g., nasal congestion, rhinorrhea, sinus headache) are important air-pollution-related health complaints, particularly in so-called problem buildings. Individual differences in nasal irritant sensitivity are therefore of both clinical and regulatory interest. To document such differences, one must first functionally define perceptual acuity to airborne irritants. In an adaptation of an established sensory testing method, the authors used the odorless irritant carbon dioxide in an electronically controlled dilution apparatus to deliver brief (approximately 3 s) pulses at controlled levels (10%-70%, vol/vol), synchronized with the inspiratory phase of the respiratory cycle. Investigators who use this apparatus can use a variant of the forced-choice paradigm for threshold determination to document nasal irritant sensitivity. The authors recruited 30 adult volunteers (17 males, 13 females; average age = 41 y, range = 19-79 y) from a university laboratory complex and from the general community. Within this group, there was a skewed distribution of carbon dioxide thresholds (arithmetic mean = 28%, geometric mean = 27% [vol/vol]). In univariate analyses, geometric mean carbon dioxide thresholds differed significantly with respect to smoking status (36% carbon dioxide in smokers versus 25% in nonsmokers; p < .005), but not with respect to age, gender, or self-reported history of allergic rhinitis. In a multivariate analysis, gender also approached significance; females tended to show better perceptual acuity than males (p = .06). Neither self-reported "vasomotor rhinitis" symptoms nor self-reported symptomatic reactivity to environmental tobacco smoke predicted carbon dioxide thresholds. Pulsed carbon dioxide is well tolerated by subjects who participate in a threshold detection task; the procedure yields a potential endpoint with which to compare individuals (and groups) with respect to nasal irritant perceptual acuity. The relationship between such acuity and nasal physiologic reactivity-as well as the generalizability of such measures to other, more environmentally realistic irritants-has yet to be defined.

Adult↗
PubMedDate not supplied

Reliability of lifetime residential history and activity measures as elements of cumulative ambient ozone exposure assessment.

UNLABELLED: Assessment of long-term effects of lifetime ambient oxidant pollution relies on ecological exposure assignment. Given the characteristics of ozone exposure profiles, with daily and seasonal peaks and clearly lower indoor concentrations, exposure misclassification is of considerable concern. This study considered residential location, time spent outdoors, and outdoors activity as major determinants of "effective" lifetime ozone exposure. Given the lack of a valid "gold standard" for these measures, we evaluated the repeatability of the retrospective assessment of these factors. METHODS: A convenience sample of 175 college students raised in California participated in the study, designed as test-retest 5-7 days apart. Lifetime residential history and outdoors activity ("moderate" and "heavy") for each residence were extensively evaluated on both visits. RESULTS: Although reliability of residential location decreased considerably with increasing number of lifetime residences, assigned lifetime ambient ozone concentrations from the nearest monitor yielded highly reliable cumulative values (intraclass correlation = 0.99). "Doers" of both "moderate" and "heavy" activity could be identified reliably (kappa = 0.83 and 0.93, respectively). Derived "hours per month" were reasonably correlated across visits (r = 0.73 for "moderate," 0.64 for "heavy") with 27% and 36% of the variance between visits, respectively. Reporting errors increased with increasing levels of activity. CONCLUSIONS: Among students 17-21 years old, lifetime residential location could be repeatedly assessed. The overall performance of the set of activity questions was reasonably reliable and compares well with other measures used in epidemiology, such as blood pressure or dietary intake. Such questionnaires may be useful tools in reducing misclassification of lifetime exposure to ambient oxidants.

Adolescent↗