[Derivation of occupational exposure limits for propylene glycol monomethyl ether based on mathematical models and uncertainty factors].

Objective: To calculate the occupational exposure limits (OELs) of propylene glycol monomethyl ether (PGME) , and to provide a reference for formulating the OELs of PGME in China. Methods: From June to August 2024, data on the physicochemical properties, toxicological test results (acute, subchronic, chronic toxicity and reproductive and developmental toxicity) , and foreign occupational exposure limits (OELs) of PGME were collected by searching databases such as China National Knowledge Infrastructure (CNKI) and PubMed, as well as the official websites of institutions such as the National Institute for Occupational Safety and Health (NIOSH) and the American Conference of Governmental Industrial Hygienists (ACGIH) . The no observed adverse effect level (NOAEL) from chronic toxicity experiments was used as the point of departure for extrapolation (PoD) , and the OELs of PGME were calculated using the OELs mathematical model, taking into account uncertainty factors such as interspecies differences and individual differences within the population. Results: PGME was a colorless and transparent liquid (relative molecular weight 90.121) , mainly absorbed through the respiratory tract and skin, and had eye and nasal irritation, hepatorenal toxicity, and reproductive and developmental toxicity. Through model calculation, the permissible concentration-time weighted average (PC-TWA) of PGME was 185.5 mg/m(3) (50 ppm) . Conclusion: The PGME PC-TWA calculated based on multi-source data, combined with mathematical models and uncertainty coefficients is scientific and reliable, and can provide a scientific basis for the formulation of PGME OELs in China.