Journal of Research in Environmental Health

Current Issue

By Issue

By Author

By Subject

Author Index

Keyword Index

About Journal

Aims and Scope

Editorial Board

Publication Ethics

Indexing and Abstracting

Related Links

FAQ

Peer Review Process

News

Editorial Policy

Advertising Policy

Investigating the Impact of Scented Candles on the Emission of Polycyclic Aromatic Hydrocarbons (PAHs) and Their Health Implications: A Systematic Review

Articles in Press

Document Type : Systematic review

Authors

1 Master's student in Environmental Health Engineering, Department of Environmental Health Engineering, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.

2 Associate Professor of Environmental Health Engineering, Department of Environmental Health Engineering, Food Safety Division, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran.

3 PhD Student in Toxicology, Department of Toxicology and Pharmacology, School of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran.

Abstract

Background and Objective: Scented candles are a potential source of indoor air pollutants, particularly polycyclic aromatic hydrocarbons (PAHs), which are classified as hazardous environmental contaminants with significant health implications. These candles, widely used in households, religious and cultural ceremonies, spas, and other enclosed environments, can emit toxic compounds contributing to indoor air pollution and associated health risks. This study aims to evaluate the health effects related to exposure to PAHs released from scented candles and to provide recommendations for choosing safer alternatives.

Materials and Methods: On February 15, 2023, a comprehensive literature review was conducted using databases such as PubMed, Web of Science, and Scopus, with relevant search terms related to scented candles and PAHs. Initially, 1,297 records were retrieved. After removing duplicates, irrelevant, and non-English articles, 180 relevant studies were reviewed in full. From these, 11 high-quality and pertinent articles were selected and synthesized in this review.

Results: The reviewed studies reveal that scented candles can emit multiple harmful substances, including volatile organic compounds (VOCs), particulate matter (PM), and PAHs. These pollutants have been linked to respiratory system disorders and an increased risk of carcinogenesis, particularly with chronic exposure. The findings highlight the urgent need for in situ monitoring and longitudinal health studies to better understand the long-term impacts of scented candle use.

Conclusion: It is essential to conduct risk assessment and apply effective exposure reduction strategies regarding scented candle use. Suggested measures include opting for cleaner alternatives (e.g., soy or beeswax candles), minimizing burn duration, using candles with natural wicks, and improving indoor air ventilation. Increased public awareness and further toxicological and epidemiological research are critical to understanding and mitigating the health impacts of these commonly used indoor products.
 
Open Access Policy: This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited. To view a copy of this licence, visit https://creativecommons.org/licenses/by/4.0/

Keywords

References
  1. Keyte IJ, Harrison RM, Lammel G. Chemical reactivity and long-range transport potential of polycyclic aromatic hydrocarbons-a review. Chemical Society Reviews. 2013;42 (24):9333-91. https://doi.org/10.1039/c3cs60147a PMid:24077263
  2. WHO. Polynuclear Aromatic Hydrocarbons in Drinking Water. Background Document for the Development of WHO Guidelines for Drinking-water Quality. WHO/SDE/WSH/03.04/59. World Health Organization Geneva, Switzerland; 2003.
  3. Zhang Y, Tao S. Global atmospheric emission inventory of polycyclic aromatic hydrocarbons (PAHs) for 2004. Atmospheric environment. 2009;43 (4):812-9. https://doi.org/10.1016/j.atmosenv.2008.10.050
  4. Buckley TJ, Lioy PJ. An examination of the time course from human dietary exposure to polycyclic aromatic hydrocarbons to urinary elimination of 1-hydroxypyrene. British journal of industrial medicine. 1992;49 (2):113. https://doi.org/10.1136/oem.49.2.113 PMid:1536818 PMCid:PMC1012075
  5. Buckley TJ, Waldman JM, Dhara R, Greenberg A, Ouyang Z, Lioy PJ. An assessment of a urinary biomarker for total human environmental exposure to benzo [a] pyrene. International archives of occupational and environmental health. 1995;67:257-66. https://doi.org/10.1007/BF00409408 PMid:7591187
  6. Jongeneelen F, van Leeuwen FE, Oosterink S, Anzion R, Van der Loop F, Bos R, et al. Ambient and biological monitoring of cokeoven workers: determinants of the internal dose of polycyclic aromatic hydrocarbons. British journal of industrial medicine. 1990;47 (7):454. https://doi.org/10.1136/oem.47.7.454 PMid:2383514 PMCid:PMC1035206
  7. Brzeźnicki S, Jakubowski M, Czerski B. Elimination of 1-hydroxypyrene after human volunteer exposure to polycyclic aromatic hydrocarbons. International archives of occupational and environmental health. 1997;70:257-60. https://doi.org/10.1007/s004200050216 PMid:9342626
  8. Aquilina NJ, Delgado-Saborit JM, Meddings C, Baker S, Harrison RM, Jacob III P, et al. Environmental and biological monitoring of exposures to PAHs and ETS in the general population. Environment international. 2010;36 (7):763-71. https://doi.org/10.1016/j.envint.2010.05.015 PMid:20591483 PMCid:PMC3148021
  9. Rengarajan T, Rajendran P, Nandakumar N, Lokeshkumar B, Rajendran P, Nishigaki I. Exposure to polycyclic aromatic hydrocarbons with special focus on cancer. Asian Pacific Journal of Tropical Biomedicine. 2015;5 (3):182-9. https://doi.org/10.1016/S2221-1691(15)30003-4
  10. U.S. Environmental Protection Agency. Human health risk assessment. 2022; [Online] Available at: https://www.epa.gov/risk/human-health-risk-assessment. Accessed April 26, 2023.
  11. European Commission. Air quality. Available at: https://environment.ec.europa.eu/topics/air_en.
  12. Boström C-E, Gerde P, Hanberg A, Jernström B, Johansson C, Kyrklund T, et al. Cancer risk assessment, indicators, and guidelines for polycyclic aromatic hydrocarbons in the ambient air. Environmental health perspectives. 2002;110 (suppl 3):451-88. https://doi.org/10.1289/ehp.110-1241197 PMid:12060843 PMCid:PMC1241197
  13. Cancer IAfRo. Polynuclear aromatic compounds, part 1. Chemical, environmental and experimental data. IARC Monographs on the Evaluation of the Carcinogenic Risk of Chemicals to Humans. 1983;32:419-30.
  14. Yan J, Wang L, Fu PP, Yu H. Photomutagenicity of 16 polycyclic aromatic hydrocarbons from the US EPA priority pollutant list. Mutation Research/Genetic Toxicology and Environmental Mutagenesis. 2004;557 (1):99-108. https://doi.org/10.1016/j.mrgentox.2003.10.004 PMid:14706522 PMCid:PMC2713671
  15. Commission E. Priority substances and certain other pollutants according to Annex II of Directive 2008/105/EC. 2015.
  16. Vo L-HT, Yoneda M, Nghiem T-D, Sekiguchi K, Fujitani Y, Vu DN, et al. Characterisation of polycyclic aromatic hydrocarbons associated with indoor PM0. 1 and PM2. 5 in Hanoi and implications for health risks. Environmental Pollution. 2024;343:123138. https://doi.org/10.1016/j.envpol.2023.123138 PMid:38097160
  17. Drwal E, Rak A, Gregoraszczuk EL. Polycyclic aromatic hydrocarbons (PAHs)-Action on placental function and health risks in future life of newborns. Toxicology. 2019;411:133-42. https://doi.org/10.1016/j.tox.2018.10.003 PMid:30321648
  18. Låg M, Øvrevik J, Refsnes M, Holme JA. Potential role of polycyclic aromatic hydrocarbons in air pollution-induced non-malignant respiratory diseases. Respiratory research. 2020;21 (1):1-22. https://doi.org/10.1186/s12931-020-01563-1 PMid:33187512 PMCid:PMC7666487
  19. Klepeis NE, Nelson WC, Ott WR, Robinson JP, Tsang AM, Switzer P, et al. The National Human Activity Pattern Survey (NHAPS): a resource for assessing exposure to environmental pollutants. Journal of Exposure Science & Environmental Epidemiology. 2001;11 (3):231-52. https://doi.org/10.1038/sj.jea.7500165 PMid:11477521
  20. Laursen KR, Christensen NV, Mulder FA, Schullehner J, Hoffmann HJ, Jensen A, et al. Airway and systemic biomarkers of health effects after short-term exposure to indoor ultrafine particles from cooking and candles-A randomized controlled double-blind crossover study among mild asthmatic subjects. Particle and Fibre Toxicology. 2023;20 (1):26. https://doi.org/10.1186/s12989-023-00537-7 PMid:37430267 PMCid:PMC10332087
  21. Orecchio S. Polycyclic aromatic hydrocarbons (PAHs) in indoor emission from decorative candles. Atmospheric Environment. 2011;45 (10):1888-95. https://doi.org/10.1016/j.atmosenv.2010.12.024
  22. Derudi M, Gelosa S, Sliepcevich A, Cattaneo A, Rota R, Cavallo D, et al. Emissions of air pollutants from scented candles burning in a test chamber. Atmospheric Environment. 2012;55:257-62. https://doi.org/10.1016/j.atmosenv.2012.03.027
  23. Petry T, Vitale D, Joachim FJ, Smith B, Cruse L, Mascarenhas R, et al. Human health risk evaluation of selected VOC, SVOC and particulate emissions from scented candles. Regulatory Toxicology and Pharmacology. 2014;69 (1):55-70. https://doi.org/10.1016/j.yrtph.2014.02.010 PMid:24582651
  24. Lee S, Wang B. Characteristics of emissions of air pollutants from mosquito coils and candles burning in a large environmental chamber. Atmospheric Environment. 2006;40 (12):2128-38. https://doi.org/10.1016/j.atmosenv.2005.11.047
  25. Global Scented Candles Market Size S, Growth Analysis, By Product Type (Containers, Pillars), By Distribution Channel (online, offline), By Raw Material (Wax, Liquid Dyes) - Industry Forecast 2023-2030. https://www.skyquestt.com/report/scented-candles-markewebt (accessed 2023-09-25).
  26. Bagheri-Nesami M, Espahbodi F, Nikkhah A, Shorofi SA, Charati JY. The effects of lavender aromatherapy on pain following needle insertion into a fistula in hemodialysis patients. Complementary therapies in clinical practice. 2014;20 (1):1-4. (Persian) https://doi.org/10.1016/j.ctcp.2013.11.005 PMid:24439636
  27. Olszowski T, Kłos A. The impact of candle burning during All Saints' Day ceremonies on ambient alkyl-substituted benzene concentrations. Bulletin of environmental contamination and toxicology. 2013;91:588-94. https://doi.org/10.1007/s00128-013-1104-6 PMid:24052143 PMCid:PMC3824304
  28. Salthammer T, Gu J, Wientzek S, Harrington R, Thomann S. Measurement and evaluation of gaseous and particulate emissions from burning scented and unscented candles. Environment International. 2021;155:106590. https://doi.org/10.1016/j.envint.2021.106590 PMid:33964641
  29. Steinemann A. Volatile emissions from common consumer products. Air Quality, Atmosphere & Health. 2015;8:273-81. https://doi.org/10.1007/s11869-015-0327-6
  30. Sundblad D. Indoor air quality-The truth about scented candles.
  31. Brans R. Candle makers. Kanerva's Occupational Dermatology. 2020:1789-92. https://doi.org/10.1007/978-3-319-68617-2_131
  32. Duque A, Ferreira A, Figueiredo J, Arezes P, Baptista J, Barroso M, et al. The air fresheners influence on the quality of the air-cross-sectional study. Occupational Safety and Hygiene IV: CRC Press; 2016. p. 399-404. https://doi.org/10.1201/b21172-76
  33. Al Khathlan N, Basuwaidan M, Al Yami S, Al-Saif F, Al-Fareed S, Ansari K. Extent of exposure to scented candles and prevalence of respiratory and non-respiratory symptoms amongst young university students. BMC Public Health. 2023;23 (1):1-8. https://doi.org/10.1186/s12889-023-15001-6 PMid:36631840 PMCid:PMC9832800
  34. Lau C, Fiedler H, Hutzinger O, Schwind K-H, Hosseinpour J. Levels of selected organic compounds in materials for candle production and human exposure to candle emissions. Chemosphere. 1997;34 (5-7):1623-30. https://doi.org/10.1016/S0045-6535(97)00458-X PMid:9134692
  35. Gelosa S, Derudi M, Sliepcevich A, Gelosa D, Nano G, Rota R, editors. Characterization of pollutants emissions from burning candles. 30th Meeting of the Italian Section of the Combustion Institute Ischia, Italy; 2007.
  36. Manoukian A, Quivet E, Temime-Roussel B, Nicolas M, Maupetit F, Wortham H. Emission characteristics of air pollutants from incense and candle burning in indoor atmospheres. Environmental Science and Pollution Research. 2013;20:4659-70. https://doi.org/10.1007/s11356-012-1394-y PMid:23288671
  37. Derudi M, Gelosa S, Sliepcevich A, Cattaneo A, Cavallo D, Rota R, et al. Emission of air pollutants from burning candles with different composition in indoor environments. Environmental Science and Pollution Research. 2014;21:4320-30. https://doi.org/10.1007/s11356-013-2394-2 PMid:24318837
  38. Ahn J-H, Kim K-H, Kim Y-H, Kim B-W. Characterization of hazardous and odorous volatiles emitted from scented candles before lighting and when lit. Journal of hazardous materials. 2015;286:242-51. https://doi.org/10.1016/j.jhazmat.2014.12.040 PMid:25588193
  39. Adamowicz J, Juszczak K, Poletajew S, Van Breda SV, Pokrywczynska M, Drewa T. Scented candles as an unrecognized factor that increases the risk of bladder cancer; is there enough evidence to raise a red flag? Cancer Prevention Research. 2019;12 (10):645-52. https://doi.org/10.1158/1940-6207.CAPR-19-0093 PMid:31399420
  40. Andersen C, Omelekhina Y, Rasmussen BB, Nygaard Bennekov M, Skov SN, Køcks M, et al. Emissions of soot, PAHs, ultrafine particles, NOx, and other health relevant compounds from stressed burning of candles in indoor air. Indoor air. 2021;31 (6):2033-48. https://doi.org/10.1111/ina.12909 PMid:34297865
Journal of Research in Environmental Health

Articles in Press, Accepted Manuscript
Available Online from 25 May 2025
Files
Share
How to cite
Statistics