Advanced REACH Tool: development and application of the substance emission potential modifying factor

Area of Science:

• Occupational Health and Safety
• Exposure Science
• Chemical Risk Assessment

Background:

• The Advanced REACH Tool (ART) is an exposure assessment tool utilizing mechanistic modeling and Bayesian approaches.
• Accurate exposure assessment relies on understanding substance emission potential, influenced by intrinsic material properties.
• Current models require refinement for predicting chemical releases in diverse workplace scenarios.

Purpose of the Study:

• To describe the intrinsic characteristics of solids and liquids that determine their release into workplace air.
• To detail the substance emission potential (SEP) as a modifying factor within the ART exposure model.
• To enhance the predictive accuracy of occupational exposure models by expanding the knowledge base on SEP.

Main Methods:

• Review of current knowledge and evidence on intrinsic properties influencing substance release.
• Identification of key factors for dust (dustiness, weight fraction, moisture), vapor (partial vapor pressure), and mist (viscosity, weight fraction) emission.
• Integration of these factors into the ART mechanistic model, using multipliers and continuous variables.

Main Results:

• Dustiness, weight fraction, and moisture content are critical for aerosol release from solids.
• Partial vapor pressure is the primary determinant for vapor emission potential.
• Viscosity and weight fraction govern mist formation potential from liquids.

Conclusions:

• The substance emission potential, considering dusts, mists, and vapors, balances theory and pragmatism in exposure modeling.
• Further research into SEP, particularly for fumes, fibers, and gases, will improve occupational exposure estimates.
• Enhanced understanding of SEP is crucial for advancing the accuracy and precision of exposure assessments.