Assessment of indoor chemical pollutant emissions from scented candle burning
DOI:
https://doi.org/10.55225/sti.754Keywords:
scented candles, indoor air quality, formaldehyde, volatile organic compounds, carbon dioxideAbstract
Background: Scented candles are widely used indoors for decorative and aromatherapeutic purposes, but combustion may contribute to the accumulation of gaseous pollutants and deterioration of indoor air quality.
Objective: To assess temporal changes in formaldehyde, total volatile organic compounds, carbon dioxide, carbon monoxide, and benzene during the combustion of three commercially available scented candles.
Materials and methods: Three different scented candle products were tested individually in a residential room with a floor area of 11 m² and an approximate volume of 25 m³. Each candle was burned for 60 minuts in a closed room. Pollutant concentrations were monitored using a low-cost ZN-MT32 multi-parameter air-quality sensor at 0, 5, 10, 15, 30, 45, and 60 minuts. One experimental run was performed for each candle.
Results: Carbon dioxide increased for all candles. The increases after 60 minuts were 414 mg/m³ for candle A, 493 mg/m³ for candle B, and 326 mg/m³ for candle C. Formaldehyde showed the maximum concentration for candle C, reaching 132 µg/m³, while maximum concentrations for candles B and A were 55 and 24 µg/m³, respectively. Maximum total volatile organic compounds concentrations were 332, 139, and 64 µg/m³ for candles C, B, and A, respectively. No measurable changes in carbon oxide or benzene were observed under the experimental conditions.
Conclusions: The tested candles produced different temporal pollutant profiles. Candle C showed the highest formaldehyde and total volatile organic compounds concentrations, whereas candle B produced the largest increase in indoor carbon dioxide. The findings support the need for adequate ventilation during prolonged candle use. Because the study used a low-cost sensor and a single experimental run per product, the results should be regarded as indicative rather than as reference-grade emission measurements.
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