Noise and Silica Exposures in Thai Stone Workers


Principal Investigators: Rick Neitzel and Kowit Nambunmee

Masters Student: Stephanie Sayler

Funding Sources: 

  • American Industrial Hygiene Foundation’s Ralph G. Smith Memorial Scholarship
  • American Industrial Hygiene Foundation’s Steven P. Levine Memorial Scholarship
  • University of Michigan Center for the Education of Women’s Menakka and Essel Bailey Fellowship
  • University of Michigan Center for Southeast Asian Studies’ Thai Studies Research Grant
  • Rackham Summer Research Award
  • Rackham Graduate Research Grant

Description: Silica is a naturally-occurring occupational carcinogen that is prevalent in many industries. Stone processing facility employees may have particularly high exposure levels, due to crushing, grinding, and transporting of limestone. Monitoring for silica can be a time-consuming and expensive task that may be especially difficult to perform in recently industrialized nations, but exposure awareness is vital for protecting worker health. Excessive noise levels also exist in this industry, with levels varying among different tasks. Noise levels are a more convenient and affordable monitoring technique for small- and medium-sized processing facilities. This study evaluated noise and silica personal measurements at a stone processing facility in Chiang Rai, Thailand, to investigate the potential for predicting occupational silica exposure utilizing more practical noise sampling methods. Research teams from the University of Michigan and Mae Fah Luang University performed personal noise and silica measurements on 46 workers during three separate work shifts each. Health history and work and safety practice information were obtained using self-administered questionnaires. These data may be used in the future to provide guidance on the potential need for respiratory protection at other local stone processing facilities based on noise and task data, reducing the need for personal air sampling for silica.

Poster and Graphical Abstract: