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Organic aerosol formation in citronella candle plumes.

Bothe M, Donahue NM - Air Qual Atmos Health (2010)

Bottom Line: Because these essential oils are unsaturated, they have a unique potential to form secondary organic aerosol (SOA) via reaction with ozone, which is also commonly elevated on summer evenings when the candles are often in use.We investigated this process, along with primary aerosol emissions, by briefly placing a citronella tealight candle in a smog chamber and then adding ozone to the chamber.In repeated experiments, we observed rapid and substantial SOA formation after ozone addition; this process must therefore be considered when assessing the risks and benefits of using citronella candle to repel insects.

View Article: PubMed Central - PubMed

ABSTRACT
Citronella candles are widely used as insect repellants, especially outdoors in the evening. Because these essential oils are unsaturated, they have a unique potential to form secondary organic aerosol (SOA) via reaction with ozone, which is also commonly elevated on summer evenings when the candles are often in use. We investigated this process, along with primary aerosol emissions, by briefly placing a citronella tealight candle in a smog chamber and then adding ozone to the chamber. In repeated experiments, we observed rapid and substantial SOA formation after ozone addition; this process must therefore be considered when assessing the risks and benefits of using citronella candle to repel insects.

No MeSH data available.


Related in: MedlinePlus

Total terpene concentrations obtained by the PTR-MS at m/z = 81 (a characteristic terpene fragment after proton transfer) for different candle input timescales. Loadings are roughly linear with burning time
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Fig1: Total terpene concentrations obtained by the PTR-MS at m/z = 81 (a characteristic terpene fragment after proton transfer) for different candle input timescales. Loadings are roughly linear with burning time

Mentions: We weighed candles before and after a fixed-length burn to obtain a burning rate of 0.51  mg  s − 1. The PTR-MS signal at m/z = 81 (characteristic of terpenes) was proportional to the injection time, as shown for three experiments in Fig. 1 using standard calibration factors for monoterpenes (Zhang et al. 2006). The primary aerosol levels were low, variable, and in some cases negligible, with an emission factor ranging from 4.3–204  μg  g − 1. Figure 2 shows a typical primary size distribution with about 2,000 particles cm − 3 peaked at 11 nm. This size range agrees with other publications concerning candle burning. Fine et al. (1999) concluded that particles for candles during normal burning (no sooting or smoldering) are smaller than 100 nm, while Wright et al. (2007) determined that aerosols from paraffin wax tealight candles are in the range of 0.4 nm–11 μm.Fig. 1


Organic aerosol formation in citronella candle plumes.

Bothe M, Donahue NM - Air Qual Atmos Health (2010)

Total terpene concentrations obtained by the PTR-MS at m/z = 81 (a characteristic terpene fragment after proton transfer) for different candle input timescales. Loadings are roughly linear with burning time
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC2914284&req=5

Fig1: Total terpene concentrations obtained by the PTR-MS at m/z = 81 (a characteristic terpene fragment after proton transfer) for different candle input timescales. Loadings are roughly linear with burning time
Mentions: We weighed candles before and after a fixed-length burn to obtain a burning rate of 0.51  mg  s − 1. The PTR-MS signal at m/z = 81 (characteristic of terpenes) was proportional to the injection time, as shown for three experiments in Fig. 1 using standard calibration factors for monoterpenes (Zhang et al. 2006). The primary aerosol levels were low, variable, and in some cases negligible, with an emission factor ranging from 4.3–204  μg  g − 1. Figure 2 shows a typical primary size distribution with about 2,000 particles cm − 3 peaked at 11 nm. This size range agrees with other publications concerning candle burning. Fine et al. (1999) concluded that particles for candles during normal burning (no sooting or smoldering) are smaller than 100 nm, while Wright et al. (2007) determined that aerosols from paraffin wax tealight candles are in the range of 0.4 nm–11 μm.Fig. 1

Bottom Line: Because these essential oils are unsaturated, they have a unique potential to form secondary organic aerosol (SOA) via reaction with ozone, which is also commonly elevated on summer evenings when the candles are often in use.We investigated this process, along with primary aerosol emissions, by briefly placing a citronella tealight candle in a smog chamber and then adding ozone to the chamber.In repeated experiments, we observed rapid and substantial SOA formation after ozone addition; this process must therefore be considered when assessing the risks and benefits of using citronella candle to repel insects.

View Article: PubMed Central - PubMed

ABSTRACT
Citronella candles are widely used as insect repellants, especially outdoors in the evening. Because these essential oils are unsaturated, they have a unique potential to form secondary organic aerosol (SOA) via reaction with ozone, which is also commonly elevated on summer evenings when the candles are often in use. We investigated this process, along with primary aerosol emissions, by briefly placing a citronella tealight candle in a smog chamber and then adding ozone to the chamber. In repeated experiments, we observed rapid and substantial SOA formation after ozone addition; this process must therefore be considered when assessing the risks and benefits of using citronella candle to repel insects.

No MeSH data available.


Related in: MedlinePlus