Dong Keon Yon, MD,¹ Sohyun Hwang, PhD,^2,3 Seung Won Lee, MD, PhD,¹ Hye Mi Jee, MD,¹ Youn Ho Sheen, MD, PhD,⁴ Jeong Hee Kim, MD, PhD,⁵ Dae Hyun Lim, MD, PhD,⁵ Man Yong Han, MD,<sup>1*

1</sup> Department of Pediatrics, CHA Bundang Medical Center, CHA University School of Medicine, Seongnam, Republic of Korea
² Department of Biomedical Science, CHA University College of Life Science, Seongnam, Republic of Korea
³ Department of Medical Statistics, CHA Bundang Medical Center, CHA University School of Medicine, Seongnam, Republic of Korea
⁴ Department of Pediatrics, CHA Gangnam Medical Center, CHA University School of Medicine, Seoul, Republic of Korea
⁵ Department of Pediatrics, Inha University Hospital, Inha University School of Medicine, Incheon, Republic of Korea

^*Corresponding authors : Professor Man Yong Han, MD
Department of Pediatrics, CHA University School of Medicine, 351 Yatap-dong, Bundanggu, Seongnam, Gyeonggi-do, 463-712, Republic of Korea

To the editor
Indoor exposure to formaldehyde is a major health concern, especially for school-age children who spend most of their time indoors(1), because at room temperature, formaldehyde evaporates from wood-based products, flooring materials, paints, fabrics, cosmetics, cleaning products, and air fresheners. Evidence supporting a link of indoor formaldehyde exposure with asthma and rhinitis is controversial, in that previous studies have reported a negative association,(2) no association,(3) and a positive association.(4) Furthermore, few studies have examined the major formaldehyde metabolite (thiazolidine-4-carboxylic acid [TZCA]), or sensitization to formaldehyde in subjects with asthma and/or rhinitis.

Keywords:  foramaldehyde;  asthma;  allergic rhinitis