July 2006
The Glycol Ether Occupational Exposure Limit (OEL)
Our Challenge
- To establish an OEL for glycol ethers.
- The existing epidemiological data were imprecise, so a physiologically-based pharmacokinetic (PBPK) model was used to estimate the delivered dose.
Our Approach
- Based on human and animal pharmacokinetic data and animal toxicity data, key parameters were identified through sensitivity analysis.
- Parameter distribution was sampled using Monte Carlo
Our Findings
- The inter-individual pharmacokinetic uncertainty factors were lower than default value of 3; thus a less conservative OEL could be derived .
- We derived three occupational exposure limits (OEL):
- OEL (8-hr TWA) of 2 ppm for EGEEA.
- OEL (8-hr TWA) of 2 ppm for EGEE
- OEL (8-hr TWA) of 0.9 ppm for EGME