1. Department of Occupational Health and Safety, Faculty of Public Health, Mahidol University, 420/1 Rajvidhi Road, Bangkok 10400, Thailand
2. Public Health, Mahidol University, Amnatcharoen Campus, Amnatcharoen 37000, Thailand
3. Department of Epidemiology, Faculty of Public Health, Mahidol University, Bangkok 10400, Thailand
4. Department of Environmental Sciences and Engineering, Gillings School of Global Public Health, The University of North Carolina at Chapel Hill, 135 Dauer Drive, Chapel Hill, NC 27599, USA
5. Department of Public Health, University of Massachusetts Lowell, 61 Wilder St., Lowell, MA 01854, USA