Taking a look at other countries’ methods. In Québec, adjustment of exposure concerns the intake dose (not the concentration level) of the substances having toxic effects. In this webinar we will explore tools for occupational hygiene application, covering miXie and the OELs adjustment tool.

Exposure to more than one chemical in the workplace is more often the rule than the exception. Similarly, the use of atypical working schedules, other than 5 d/w and 8 h/d, continues to increase. Since the WES have been determined for single exposure and for “regular” schedules, how can the risk in these circumstances be estimated without bias?

Exposure to more than one chemical in the workplace is more often the rule than the exception. Similarly, the use of atypical working schedules, other than 5 d/w and 8 h/d, continues to increase. Since the WES have been determined for single exposure and for “regular” schedules, how can the risk in these circumstances be estimated without bias? With respect to mixtures, legislation often includes a similar provision to the one found in ACGIH® TLVs® Book:
“Where two or more substances are present in the work location and where they have similar effects on the same organs of the human body, the effects of these substances are considered to be additive, unless it is established otherwise”.

Also, ACGIH® mentions different approached to adjust their TLVs® and some legislations have introduced their own rules to adjust their WES or, in UK the exposure itself.

That said, how can an occupational hygienist consider these two requirements, the "conditional additivity" and/or the adjustment of the WES for unusual schedules? This is not a simple challenge to solve! More than 20 years ago, a Canadian research team studied the question and designed a computer tool to support occupational hygienists in this questioning:

“Why or why not add the exposure of two or more substances?” and ... “How to adjust the WES according to the schedules and health effects of a substance?” The application, named “miXie”, used in Québec now integrates those two questions.

In this lecture, the history, original intent, algorithm, and structure of miXie will be presented, and we will show how it is used as a decision support tool by occupational hygienists through a live demonstration. In addition, tools from 3 different jurisdictions (Ontario, Québec, and Australia) for the adjustment of WES will be presented to illustrate the different approaches.

Speaker

Daniel Drolet

Daniel has worked for 33 years at the Québec Research Institute in Occupational Health and Safety (IRSST) in Montréal, Canada and is currently working for Hydro-Québec. He and his collaborators have developed numerous applications for both laboratory and industrial hygiene uses, for the benefit of the industrial hygiene community (miXie, OELs adjustment tool, Heat Stress tools, ProtecPo, Saturisk ... question: which of these are related to adjusting WELs and which are not?).

Daniel is also an active member of the AIHA Exposure Assessment Strategies Committee and has been involved in their “cool new tools” development (Multilanguage IHSTAT, IHMOD 2.0, IHEST, IH SkinPerm, DRAM, SDM 2.0 and IHStat_Bayes question: which of these are related to adjusting WELs and which are not?). He has been selected in 2012 by AIHA to receive the Edward J. Baier Achievement Award in recognition of his significant contribution to industrial hygiene in recent years.