Toxicity of glycol ethers during exercise

Glycol ethers, primarily used as solvents, represent a global market of several million tonnes and are found in a wide range of consumer products for both domestic and professional use (e.g., paints, adhesives, cosmetics, cleaning products). The general population is chronically exposed to glycol ethers via inhalation, particularly to propylene glycol ether derivatives, which dominate the market. Workers such as painters and cleaners are especially exposed, as they handle these substances at higher concentrations and for prolonged periods, up to 8 hours per day, in occupational settings.

The human toxicity of these compounds is still poorly characterized, making it difficult for regulatory bodies to establish clear surveillance strategies and usage recommendations. However, some studies have reported adverse respiratory effects in workers exposed to glycol ethers.

Objectives

The primary objective of this research project is to evaluate potential respiratory-related changes in healthy volunteers exposed to propylene glycol ether. Participants are exposed to low and controlled concentration in a dedicated exposure chamber. To mimic the physical exertion typically experienced by exposed workers, participants perform moderate and maximal exercise on a cycle ergometer during the exposure.

Blood and urine samples are collected to assess internal dose, as well as the toxicokinetics of the substance. In addition, blood gases are analyzed. During exercise, measurements are continuously taken of quadriceps oxygenation, heart rate variability, and cardiac output, to evaluate potential changes in muscle tissue oxygenation.