Biomedical subjects

Susan M Kennedy

Publications and source records attributed to Susan M Kennedy.

23 records · Page 2Linked to original sources

PubMed2003

Role of underlying pulmonary obstruction in short-term airway response to metal working fluid exposure: a reanalysis.

BACKGROUND: Among epidemiologic studies that found evidence for associations between exposures to metal working fluids (MWF) and pulmonary function impairments, one found effects restricted to workers with fixed obstruction at baseline. We reanalyzed a previously published study on MWF exposure and cross-shift pulmonary function to further evaluate this finding. METHODS: Pulmonary function was measured cross-shift on Monday and Friday in 131 male automotive workers. Quantitative personal MWF exposure data were available. Those with an FEV(1)/FVC ratio of <or=0.72 were considered obstructed. RESULTS: There was a trend towards increasing incidence of cross-shift decrement in FEV(1) as MWF exposure increased in the full cohort as well as when the results were restricted to the 19 (14.5%) who were obstructed. Those with obstruction were slightly more likely to show decrements in FEV(1) on Fridays. Removing the obstructed subgroup did not appear to substantially weaken the exposure-response relation. CONCLUSIONS: No important differences were found in cross-shift effects of MWF between obstructed and non-obstructed workers.

Adult↗

PubMed2003

Exposure assessment in epidemiology: does gender matter?

BACKGROUND: The pathway from potential hazards in the work environment to the measurement or estimation of personal exposure for epidemiologic studies comprises many steps, each of which can be influenced by factors that may or may not differ by gender. This article explores this pathway to address the question, "Should the potential for gender differences be taken into account in the activity of exposure assessment for epidemiologic studies?" METHODS: Evidence from previously published studies and data from the investigators' own research were examined to explore whether or not several theoretical sources of gender 'bias' in exposure assessment have been found in actual studies. Sources of bias examined included: differences in job tasks despite same job titles; differences in delivered exposure due to differences in protective equipment, body size, or other relationships to exposure sources; and differences in estimated exposure arising from study methods or design. RESULTS AND CONCLUSIONS: Evidence was found for gender differences (and thus potential bias) from all these sources, at least in some studies. We conclude that the answer to the question posed, "Does gender matter, in exposure assessment for epidemiology?" is a qualified 'yes,' but that the magnitude and direction of the potential bias cannot be predicted, a priori. Am. J. Ind. Med. 44:576-583, 2003.

Epidemiologic Studies↗

PubMed2003

Truncating the dose range for methacholine challenge tests: three occupational studies.

The methacholine challenge test protocol was assessed in the reanalysis of three occupational studies. We evaluated the impact of truncating the range of methacholine on responsiveness, as defined by slope and PC(20). In original analysis, reactivity was similar for apprentices and auto body shop workers, whereas boilermakers were more responsive. Truncating high concentrations did not change the classification of subjects with PC(20) <8 or 16 in any population. However, when responsiveness was measured by slope, the mean responsiveness increased, from -7.9 to -15.3 for apprentices and -7.2 to -10.0 for auto-body shop workers. Results support the American Thoracic Society's recommended maximum of 16 mg/ml and provide evidence that extending the dose range beyond that does not increase sensitivity, whereas stopping before 16 may exaggerate response. Furthermore, to ensure validity, neither slope nor PC(20) should be extrapolated beyond data.

Adult↗

PubMed2003

Beta(1-->3)-glucan exposure levels among workers in four British Columbia sawmills.

Beta(1-->3)-glucans were extracted from wood dust samples taken during the summer of 1997 at four British Columbia sawmills. Personal dust samples were collected using a GSP-sampler for inhalable dust and the sampling strategy targeted all production and maintenance jobs at least once at each mill. Potential exposure determinants data were documented concurrently, including weather conditions, log storage methods, wood conditions, species, production level, jobs and tasks. beta(1-->3)-glucans were measured by enzyme inhibition immunoassay (EIA). A total of 223 personal beta(1-->3)-glucan samples were analyzed. 45.7% were below the limit of detection (LOD). Geometric mean concentration ranged from 3.5 to 18.9 micro g/m(3) across the four mills. The highest levels were measured at the Interior mills, particularly in the log processing and sawmill areas. Multivariate regression models indicated that land-based log storage, clean-up jobs, high wood dust concentration, lumber yard department and the interaction between land-based log storage method and log processing department were associated with increased beta(1-->3)-glucan concentration.

Aerosols↗

PubMedDate not supplied

Exposures and their determinants in radiographic film processing.

Radiographers process X-ray films using developer and fixer solutions that contain chemicals known to cause or exacerbate asthma. In a study in British Columbia, Canada, radiographers' personal exposures to glutaraldehyde (a constituent of the developer chemistry), acetic acid (a constituent of the fixer chemistry), and sulfur dioxide (a byproduct of sulfites, present in both developer and fixer solutions) were measured. Average full-shift exposures to glutaraldehyde, acetic acid, and sulfur dioxide were 0.0009 mg/m3, 0.09 mg/m3, and 0.08 mg/m3, respectively, all more than one order of magnitude lower than current occupational exposure limits. Local exhaust ventilation of the processing machines and use of silver recovery units lowered exposures, whereas the number of films processed per machine and the time spent near the machines increased exposures. Personnel in clinic facilities had higher exposures than those in hospitals. Private clinics were less likely to have local exhaust ventilation and silver recovery units. Their radiographers spent more time in the processor areas and processed more films per machine. Although exposures were low compared with exposure standards, there are good reasons to continue practices to minimize or eliminate exposures: glutaraldehyde and hydroquinone (present in the developer) are sensitizers; the levels at which health effects occur are not yet clearly established, but appear to be lower than current standards; and health effects resulting from the mixture of chemicals are not understood. Developments in digital imaging technology are making available options that do not involve wet-processing of photographic film and therefore could eliminate the use of developer and fixer chemicals altogether.

Acetic Acid↗