1. National Institute of Environmental Health Sciences, National Health Research Institutes, Miaoli 350, Taiwan
2. Department of Medical Research, China Medical University Hospital, China Medical University, Taichung 404, Taiwan
3. Research Center for Environmental Medicine, Kaohsiung Medical University, Kaohsiung 701, Taiwan
4. Department of Environmental and Global Health, College of Public Health and Health Professions (PHHP), University of Florida, Gainesville, FL 326, USA