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Biomedical subjects

H Weill

Publications and source records attributed to H Weill.

At least 73 records · Page 4Linked to original sources
PubMed1982

Five-year longitudinal study of workers employed in a new toluene diisocyanate manufacturing plant.

The respiratory health of 277 workers in a new toluene diisocyanate (TDI) manufacturing plant was studied prospectively during 5 yr of exposure. Personal TDI monitors were used to continuously measure peak and 8-h time-weighted average (TWA) concentrations in over 2,000 samples. Longitudinal change in pulmonary function was assessed in 223 men in whom 3 or more data points allowed construction of individual slopes of annual change. Regression of annual change on smoking (pack-years), atopic status, and cumulative TDI exposure dichotomized at 68.2 parts per billion (ppb) months into low and high exposure groups showed significant effects of smoking on spirometric tests and lung volumes. After adjusting for pack-years of smoking, the 74 men in the high cumulative TDI exposure category had significantly larger declines in FEV1, %FEV, and FEF25--75% than did the 149 men in the low category. Annual change in FEV1 was then examined in 6 smoking-exposure categories: in never smokers, average annual decline was 38 ml/yr greater in those with higher cumulative TDI exposure. Current and previous cigarette smokers did not show this effect of cumulative TDI exposure. Analysis of FEV1 change by time above 20 ppb TDI yielded a similar result in never smokers, a 24 ml/yr excess average decline attributable to longer time above 20 ppb. In current cigarette smokers, those with longer time above 20 ppb had excess decline of 18 ml/yr (42 versus 24 ml/yr). our low and high cumulative exposure groups spent 2 and 15%, respectively, of their working time above 5 ppb TDI. The different health effects observed in these groups supports the NIOSH-recommended standard of 5 ppb TDI as an 8-h TWA.

Adult↗
PubMed1981

Immune complexes and autoantibodies in silicosis.

Serum specimens from 53 patients with silicosis were examined for the presence of antinuclear antibodies (ANA), rheumatoid factor (RF), immunoglobulins, and immune complexes. These humoral immunologic parameters were compared with radiographic changes and pulmonary function studies. A significant percentage of patients had an increased prevalence of ANA, RF, and immunoglobulin elevation (IgG, IgA). Immune complexes determined by the Raji-cell assay were detected in 31% of the patients. However, there was no significant correlation between any humoral immunologic abnormality and radiographic changes or declines in pulmonary function tests. These findings suggest that humoral immunologic abnormalities are not directly responsible for the lung changes in silicosis and cannot be used as "guides" to predict severity or progression of disease.

Adult↗
PubMed1981

Factors influencing the interpretation of FEV1 declines across the working shift.

An analysis of variability within individuals was conducted for FEV1, obtained from subjects employed in the cottonseed industry. Individual SDs ranged from .020 to .428 L. The within-subject SD of the preshift-postshift difference ranged from .014 to .302 L. When within-subject variability of FEV1 was analyzed in relation to symptoms, smoking history, and shift, the only statistical difference occurred in the 14 bronchitic subjects (.141 L) relative to the 179 without bronchitis (.099 L), and the three subjects with byssinosis (.192 L) relative to those without symptoms (.102 L). Changes over the working shift were significantly different for evening relative to morning and night shifts, even though there was no significant difference in smoking status, symptoms, exposure, race, age, years employed in the mill, and work area. In addition, baseline measurements were not significantly related to shift. Therefore, the effect of individual variability, symptoms, and shift should be considered if an accurate classification of reactors based on change in FEV1 across the shift is to be obtained.

Bronchitis↗
PubMed1981

Occupational lung diseases.

Until workers can be effectively protected from the dusts, gases, and vapors that cause occupational lung diseases, clinicians must focus on careful history taking, precise diagnosis, and prompt therapy to relieve or reduce respiratory disability.

Air Pollutants↗
PubMed1980

Evaluation of performance of a beta absorption dust monitor.

Dust sampling is one of the important tools utilized by industrail hygienists in their evaluation of the work environment. It usually is performed to test compliance with regulations, to identify emission sources, in epidemiologic studies or for determination of the dose inhaled by animals in toxicological studies.

Aerosols↗
PubMed1980

Interaction of atopy and exposure to cotton dust in the bronchoconstrictor response.

A survey of 255 workers in four cottonseed crushing mills included a respiratory health questionnaire, allergy skin testing, and measurements of lung function over the Monday working shift. Atopy was defined as having two or more positive weal reactions to common inhalant antigens. Categories of exposure to dust were based on the stage of milling, and one category contained workers with continuous exposure to cotton dust derived from linters, the cotton fibres adherent to cottonseed. Atopy and exposure to dust were found to have significant interaction: large mean declines in FEV1 and FEF 25-75 occurred only in the workers exposed to linter dust who were also atopic. Skin-testing surveys in cotton textile mills have concentrated on specific cotton antigen reactivity and its first-order relations to symptoms. Our results indicate a need to identify atopic workers, and to search for interactions between atopy and other variables that may influence acute changes in expiratory flow rates.

Adult↗
PubMed1980

Progression of asbestos radiographic abnormalities: relationships to estimates of dust exposure and annual decline in lung function.

The determinants of radiographic worsening were examined in a cohort of 244 asbestos-cement manufacturing workers. Progression of irregular small opacities was related to higher average and cumulative dust exposures. Progression of pleural thickening or pleural plaques was related to length of exposure and time since first exposure, but not to average or cumulative exposure. Larger declines in forced vital capacity and forced expiratory volume (one second) were related to larger cumulative dust exposures and to progression of irregular small opacities and pleural thickening. Progression of pleural calcification was not associated with significantly declines in lung function. Changes in lung diffusing capacity did not correlate with measures of dust exposure or with progression of radiographic abnormalities.

Adult↗
PubMed1980

Lung cancer risk associated with manufacture of asbestos-cement products.

The mortality experience of a cohort of 5645 Louisiana asbestos-cement workers with a minimum follow-up of 20 years was related to total dust, duration and concentration of exposure and fibre type. Excess respiratory cancer risk was detected in workers with moderate and heavy asbestos dust exposure, but no excess risk occurred in categories of lower exposure. Mortality due to all other causes was normal. Both duration and level of exposure were shown to contribute to risk; both variables exhibited levels at which no excess mortality was detected. Workers exposed to both chrysotile and crocidolite appeared to be at greater risk of respiratory malignancy than those with exposure to chrysotile only.

Adult↗