The Global Landscape of Occupational Exposure Limits--Implementation of Harmonization Principles to Guide Limit Selection.

Occupational exposure limits (OELs) serve as health-based benchmarks against which measured or estimated workplace exposures can be compared. In the years since the introduction of OELs to public health practice, both developed and developing countries have established processes for deriving, setting, and using OELs to protect workers exposed to hazardous chemicals. These processes vary widely, however, and have thus resulted in a confusing international landscape for identifying and applying such limits in workplaces. The occupational hygienist will encounter significant overlap in coverage among organizations for many chemicals, while other important chemicals have OELs developed by few, if any, organizations. Where multiple organizations have published an OEL, the derived value often varies considerably-reflecting differences in both risk policy and risk assessment methodology as well as access to available pertinent data. This article explores the underlying reasons for variability in OELs, and recommends the harmonization of risk-based methods used by OEL-deriving organizations. A framework is also proposed for the identification and systematic evaluation of OEL resources, which occupational hygienists can use to support risk characterization and risk management decisions in situations where multiple potentially relevant OELs exist.

Estimation of exposure from spilled glutaraldehyde solutions in a hospital setting.

Glutaraldehyde is commonly used in hospitals for cold disinfection of instruments which may be damaged by autoclaving. The increased use of automatic washer/disinfection machines has resulted in a greater risk of spills than with manual methods. A series of experiments was conducted to answer two related research questions: what was the likely range of airborne concentrations when glutaraldehyde is spilled, and are commonly used personal protective equipment ensembles effective and practicable in use? Objective measurements using three sampling methods (two pumped methods based on OSHA 64, one using treated filters and the other based on adsorbent tubes, and a Glutaraldemeter direct reading instrument) were conducted with spills of various surface areas of both 2 and 50% solutions of glutaraldehyde. Results ranged between < 0.01 and 1.4 ppm. Two personal protective equipment ensembles were tested. One was based on a half-facepiece respirator with gas-tight goggles, while the other comprised a full-facepiece cartridge respirator. Both ensembles gave adequate protection against irritation, although in use the half-facepiece respirator and goggles tended to interfere with each other. The direct reading instrument generally underestimated the glutaraldehyde concentrations, although there was a significant association with the results obtained using the method based on adsorbent tubes.