Exposure Assessment and Hazard Evaluation of a Polyoxyalkylene Glycol Aerosol Released fron Non-CFC Mobile Air-Conditioning System

Abstract

This study was designed to evaluate the potential health hazards resulting from an unintentional exposure to a polyoxyalkylene glycol (PAG, a lubricant) aerosol from a non-CFC air-conditioning (A/C) refrigerant system. Four scenarios simulating the worst-case exposures to drivers, mechanics, or test engineers were used as test conditions. The time-averaged total airborne particulate concentration over a 20-min period ranged from 0.1 to 42 mg/m3. In each case the lubricant aerosol had a mass median aerodynamic diameter (MMAD) of 1 µm (σg of 2.3–2.8). The peak PAG aerosol concentration of 155 mg/m3 inside an unvented simulated vehicle cabin was reached 30 sec after a simulated total rupture of the entire A/C refrigerant system into the vehicle compartment, an extremely unlikely event. However, with ventilation at the “normal” A/C setting, peak concentration inside the vehicle cabin was 14 mg/m3, and background levels were reached in less than 3 min. Although pulmonary toxicity associated with subacute expos...