Migration and deposition characteristics of micro-dust in the human upper airway in dust-polluted tunnel environments

Area of Science:

• Occupational Health
• Environmental Science
• Biomedical Engineering

Background:

• Coal mining environments present significant dust pollution hazards.
• Understanding micro-dust behavior in the human upper airway (HUA) is critical for assessing health risks.

Purpose of the Study:

• To numerically analyze the migration, deposition, and escape characteristics of micro-dust in the HUA.
• To investigate the influence of different labor intensities and dust properties on deposition patterns.

Main Methods:

• Numerical simulation of micro-dust transport and deposition in a model of the HUA.
• Validation of simulation results against experimental data (maximum deviation 8.97%).
• Analysis of dust behavior under varying expiratory flow rates and particle densities.

Main Results:

• Expiratory flow secondary motion creates vortices prone to dust deposition, particularly in the pharynx for 1-15 μm particles (deposition fraction up to 77.13% for 15 μm dust).
• Larger dust particles (20-80 μm) are poorly exhaled, depositing in the nasal turbinate and nasopharynx.
• Increased particle density reduces the escape rate of smaller dust particles (1-15 μm); larger dust deposition is less affected by density.

Conclusions:

• Labor intensity significantly impacts dust deposition sites and fractions within the HUA.
• Findings aid in evaluating health risks associated with coal mine dust exposure.
• Results can inform the development of improved dust control technologies for safer mining environments.