Acute symptoms associated with asphalt fume exposure among road pavers.

BACKGROUND: Although asphalt fume is a recognized irritant, previous studies of acute symptoms during asphalt paving have produced inconsistent results. Between 1994 and 1997, the National Institute for Occupational Safety and Health (NIOSH) evaluated workers at seven sites in six states. METHODS: NIOSH (a) measured exposures of asphalt paving workers to total (TP) and benzene-soluble particulate (BSP), polycyclic aromatic compounds, and other substances; (b) administered symptom questionnaires pre-shift, every 2 hr during the shift, and post-shift to asphalt exposed and nonexposed workers; and (c) measured peak expiratory flow rate (PEFR) of asphalt paving workers when they completed a symptom questionnaire. RESULTS: Full-shift time-weighted average exposures to TP and BSP ranged from 0.01 to 1.30 mg/m(3) and 0.01 to 0.82 mg/m(3), respectively. Most BSP concentrations were <0.50 mg/m(3). Asphalt workers had a higher occurrence rate of throat irritation than nonexposed workers [13% vs. 4%, odds ratio (OR) = 4.0, 95% confidence interval (CI): 1.2-13]. TP, as a continuous variable, was associated with eye (OR = 1.34, 95% CI: 1.12-1.60) and throat (OR = 1.40, 95% CI: 1.06-1.85) symptoms. With TP dichotomous at 0.5 mg/m(3), the ORs and 95% CIs for eye and throat symptoms were 7.5 (1.1-50) and 15 (2.3-103), respectively. BSP, dichotomous at 0.3 mg/m(3), was associated with irritant (eye, nose, or throat) symptoms (OR = 11, 95% CI: 1.5-84). One worker, a smoker, had PEFR-defined bronchial lability, which did not coincide with respiratory symptoms. CONCLUSIONS: Irritant symptoms were associated with TP and BSP concentrations at or below 0.5 mg/m(3).

Historical risks of tuberculin skin test conversion among non-physician staff at a large urban hospital.

BACKGROUND: Nosocomial transmission of Mycobacterium tuberculosis among workers at a 1000-bed inner-city hospital led to an extensive evaluation of this risk among workers with potential exposure to TB patients or laboratory specimens. METHODS: Retrospective cohort study to determine the incidence and risk of tuberculin skin test (TST) conversions among workers employed 1/1/90 to 9/30/92. RESULTS: Personal, community, and occupational risk factors were evaluated in 2,362 workers with potential M. tuberculosis exposure and 886 workers with no known exposure. The 33-month cumulative rate of TST conversion was 5.8% for potentially exposed workers and 2.0% for controls (RR 3.6; 95% CI; 2.2-5.8). Among workers with potential M. tuberculosis exposure, statistically significantly elevated risks were found for nurses, laboratory technicians, pharmacy workers, phlebotomists, housekeepers, clerks, emergency room workers, and emergency responders. CONCLUSIONS: Workers with patient contact and those employed in certain occupational groups were at increased risk for occupational M. tuberculosis infection.