1. Air Toxic and Environmental Analysis Laboratory, Hungkuang University, Sha-Lu, Taichung 433, Taiwan,
2. The chief of Intensive Care Unit, Chien Yu Regional Teaching Hospital, Lin Yuang, Kaohsiung 832, Taiwan
3. Air Toxic and Environmental Analysis Laboratory, Hungkuang University, Sha-Lu, Taichung 433, Taiwan
4. Division of Biochemical Toxicology, National Center for Toxicological Research, Jefferson, Arkansas 72079, USA