Application of a novel exposure limit approach for co-exposure of ‎chemicals: a field study by in-vitro design

ABSTRACT

This study has suggested an occupational exposure limit (OEL) based on the co-exposure approach in an iron-foundry industry. Respirable dust was collected in an iron casting industry using the NIOSH 0600 method. The DNA damage was obtained by comet assay. The lower confidence interval of the benchmark dose (BMDL) was employed for exposure limit evaluation. The estimated BMDL of the cell line was extrapolated to human subjects. Based on the Hill model, a BMDL 1.65 µg for chemical mixture has been estimated for the A549 cell line. According to uncertainty factors, permitted daily exposure (PDE) was predicted in humans. However, PDE of 3.9 μg/m³ was specified as the time-weighted average limit for toxic respirable dust in the casting industry. In this study, OEL for active respirable dust in the casting industry has been proposed. The industry-based standard for active respirable dust has been proposed for better management of co-exposure.

KEYWORDS:

• Co-exposure
• benchmark dose
• exposure limit approach
• A549
• casting industry

Acknowledgments

This study is related to the project NO 1400/66863 From Student Research Committee, Shahid Beheshti University of Medical Sciences, Tehran, Iran. We also appreciate the “Student Research Committee” and “Research & Technology Chancellor” at Shahid Beheshti University of Medical Sciences for their financial support of this study.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Data availability

The raw/processed data required to reproduce these findings cannot be shared at this time due to technical or time limitations.

Additional information

Funding

This work was supported by Student Research Committee, Shahid Beheshti University of Medical Sciences the under [Grant NO 1400/66863].