Introduction: The assessment of the overall exposure of workers to hazardous substances is fundamental for their comprehensive protection. This includes oral exposure to hazardous substances, which can be relevant for total exposure depending on the specific workplace and substance. However, monitoring and available modelling approaches for a sound assessment of this exposure pathway are limited. The development of an occupational oral exposure assessment model requires knowledge of the contributing mechanisms, including worker behaviour and occupational hygiene practice. In addition, monitoring data on occupational oral exposure are a prerequisite for the evaluation of an exposure model.

Methods: A systematic literature review was conducted using the PRISMA method. Studies describing behaviours and occupational hygiene practices with regard to oral occupational exposure, and studies including measured data sets for the model evaluation were identified. The included data were then extracted and evaluated in a meta-analysis.

Results: 142 studies addressing oral occupational exposure were identified in the area of behaviour and occupational hygiene. Frequencies of hygiene practices were aggregated. The influence of worker training was investigated and the controllability of individual behaviour was described qualitatively. For the model evaluation, 9 publications were identified that included monitoring data for oral occupational exposure. These publications use 5 different sampling approaches and describe 4 different substance groups.

Discussion: The systematic literature search on behaviour and occupational hygiene provides a partly quantitative basis for the model-based description of occupational oral exposure to hazardous substances. Oral exposure to hazardous substances cannot be prevented by good occupational hygiene practices alone, as a relevant part of the causal personal behaviour (eg touching the own face) is subconscious and can therefore not be avoided completely. The identified database serves as a basis for the later model evaluation. The usability of the data sets depends on whether the future model input parameters are documented in the studies.

This article is published in the Journal "Annals of Work Exposures and Health" (2025).