Assessment of exposure to TDI and MDI during polyurethane foam production in Poland using integrated theoretical and experimental data

The aim of this study was to develop an optimal strategy for the assessment of inhalation exposure to isocyanates such as TDI and MDI in the production of polyurethane foam by integration of theoretical and experimental data. ECETOC TRA and EASE predictive models were used to determine the estimated levels of exposure to isocyanates. The results of our study suggest that both applications EASE and ECETOC TRA can be used as a screening 1st Tier tool in this case study. PROC12 ECETOC TRA category can be linked to exposure on TDI during polyurethane foam manufacturing because it is working properly and exceeds 90th percentile measured concentration with factor 3 and the maximum measured value with factor 1, 5. The value estimated by using category PROC2 is underestimated so this category should not be linked to this scenario. At the same time, the applications of EASE overstate the expected concentrations although the scenario “Use in closed process” seems to underestimate the exposure at the “lower end”. For MDI the both models estimate exposure in a conservative manner.

► We measured the concentration of the mixture of isomers of TDI and MDI in the ambient air of work environment in a plant manufacturing polyurethane foam.
► We used ECETOC TRA and EASE predictive models to determine the estimated levels of exposure to isocyanates: TDI and MDI.
► The study confirmed the feasibility of using of both models, i.e., EASE and ECTOC TRA, as a screening tool for assessing occupational exposure and health risk.
► In the case of MDI, both models have estimated the values of the concentrations in a conservative manner.
► Application of ECETOC TRA to assess occupational exposure to TDI in the process of polyurethane foam blowing leads to the conclusion that in order to ensure that the process polyurethane foam blowing is properly controlled, workers employed at the described workplace should be periodically provided with full masks to ensure respiratory protection when performing activities involving exposure to TDI.