ANSES proposes a new tool to limit peaks of exposure to chemicals in the workplace

Introduction
Occupational exposure limits (OELs) are an important tool used to protect workers from adverse chemical exposures and their detrimental effects on health. Thus, setting OELs for hazards in the workplace has been an integral component of worker health protection programs for many decades

Methods
In France, these OELs are established by ANSES (French Agency for Food, Environmental and Occupational and Health & Safety) via a specific Committee dedicated to this topic. The approach involves developing OELs by expert review of the available evidence and setting levels based primarily on health considerations. One of the major questions that the Committee is considering is whether a limitation of peak exposures is necessary and whether, when scientific data are lacking, there exists a generic methodology to determine short-term limit values (STEL) that may assist in limiting the risks of peak exposures. Peak exposure intensity is often associated with acute health outcomes, whereas cumulative exposure is generally more relevant for diseases with long induction times. The 8-hour time weighted average (-8h-TWA) does not provide the best yardstick for the prevention of all health risks.

Results
For this purpose, the ANSES OEL Committee recommends:
- applying the ceiling value (an airborne concentration that should never be exceeded even for an instant) for fast-acting hazardous substances.
- limiting the number of exposure peaks, even when scientific data are lacking; therefore, a proportionality factor of 5 is proposed to link the 8h-TWA to the 15min-STEL.

Discussion
This recommendation is available if the standard reference procedures for the measurement of exposure levels in workplace atmospheres are relevant. This issue should be discussed for each substance