A proposed methodology for setting occupational exposure limits for hydrocarbon solvents

Area of Science:

• Industrial Hygiene
• Occupational Health
• Toxicology

Background:

• Hydrocarbon solvents often have complex compositions, making individual OEL development challenging.
• Existing OELs are limited due to detailed studies focusing on only a few representative constituents.

Purpose of the Study:

• To propose a method for developing occupational exposure limits (OELs) for complex hydrocarbon solvents.
• To introduce a grouping strategy and reciprocal calculation procedure (RCP) for OEL determination.

Main Methods:

• Grouping hydrocarbon solvent constituents based on similar physical, chemical, and toxicological properties.
• Assigning guidance values to each group.
• Calculating unique OELs using a reciprocal calculation procedure (RCP) based on liquid composition.

Main Results:

• The RCP provides a practical method for calculating OELs for complex hydrocarbon solvents.
• Guidance values are based on acute central nervous system depression and irritation effects.
• The method is consistent with ACGIH guidance and UK HSE recommendations.

Conclusions:

• The proposed grouping and RCP method simplifies OEL development for hydrocarbon solvents.
• This approach yields OEL recommendations aligned with occupational experience and regulatory advice.
• The method requires limited compositional data and is practical for manufacturers.