Characteristics of Gas Phase Carbonyl Emission and Excess Risk from Incense Stick Burning Nguyen Nhu Bao Chinh & Yusuke Fujii & To Thi Hien & Norimichi Takenaka Received: 7 January 2020 /Accepted: 28 May 2020 # Springer Nature Switzerland AG 2020 Abstract Incense stick burning is one of casual house- hold activity, especially in East and Southeast Asian countries, including Vietnam. In this study, nine incense stick types were collected from Vietnam and investigat- ed the carbonyl emission profile. The result showed that in ten analyzed carbonyl compounds, propionaldehyde (3–84%, avg. 32%), acetaldehyde (8–90%, avg. 30%), and acetone (0–38%, avg. 9%) were the most abundant in terms of total weight emitted carbonyls, respectively. The fourth abundant aldehyde was HCHO (1–26%, avg. 8%). The concentration of formaldehyde (HCHO) in released smoke ranged from 46.65 ± 4.44 to 596.89 ± 279.17 μg/m 3 (38.02 ± 3.62 to 486.46 ± 242.19 ppb). High concentration of these carbonyls can pose health risk. Therefore, the personal risk assessment of HCHO inhalation exposure was carried out by the burning simulation in a small unventilated room. The risk calcu- lation showed that the cancer risk is 1.81 × 10 -5 , 24% higher than the base risk. However, the risk may be much higher. Keywords Carbonyls . Incense stick . Emission . Health risk 1 Introduction Incense burning is the feature associated with many cultures and religions in the world, especially in East Asian and Southeast Asian regions (Chen and Ho 2016; Guo et al. 2004; He et al. 2018; Lee and Wang 2004; Wei et al. 2018). It gets deep in the subconsciousness of people as a very usual living activity, even in present modern societies. Because people spend most of their lifetime indoors and because of habit of burning incense, the health risk for incense burning should be concerned. A wide variety of substances used to produce incense include resins (such as frankincense and myrrh), spices, aromatic wood and bark, herbs, seeds, roots, flowers, essential oils, and synthetic substitute chemicals that may be harmful to human health (Lee and Wang 2004; Višić et al. 2018). Burned incense released a variety of chemicals (organic acid, hydroxyl compounds, quinone, carbonyls, polyaromatic hydrocarbons (PAHs), and in- organic pollutants) (Chuang et al. 2011; Guo et al. 2004; Lee and Wang 2004; Višić et al. 2018; Yang et al. 2012). Among of them, carbonyl compounds are carci- nogenic potential compounds (Lui et al. 2017; Manoli et al. 2016; Yang et al. 2010). Among carbonyl com- pounds, HCHO is a human carcinogen (group B1- Probably Carcinogenic to Humans by United States Environmental Protection Agency (US-EPA)) and Water Air Soil Pollut (2020) 231:297 https://doi.org/10.1007/s11270-020-04674-z N. N. B. Chinh (*) Graduate School of Engineering, Osaka Prefecture University, 1-1 Gakuen town, Naka Ward, Sakai City, Osaka Prefecture, Japan e-mail: nnbchinh@hcmus.edu.vn N. N. B. Chinh : T. T. Hien Faculty of Environment, Vietnam National University Ho Chi Minh City - University of Science, Ho Chi Minh City, Vietnam Y. Fujii : N. Takenaka Graduate School of Humanities and Sustainable System Sciences, Osaka Prefecture University, Sakai City, Osaka, Japan