Emissions of soot, PAHs, ultrafine particles, NO _x, and other health relevant compounds from stressed burning of candles in indoor air

Abstract

Burning candles release a variety of pollutants to indoor air, some of which are of concern for human health. We studied emissions of particles and gases from the stressed burning of five types of pillar candles with different wax and wick compositions. The stressed burning was introduced by controlled fluctuating air velocities in a 21.6 m3 laboratory chamber. The aerosol physicochemical properties were measured both in well‐mixed chamber air and directly above the candle flame with online and offline techniques. All candles showed different emission profiles over time with high repeatability among replicates. The particle mass emissions from stressed burning for all candle types were dominated by soot (black carbon; BC). The wax and wick composition strongly influenced emissions of BC, PM2.5, and particle‐phase polycyclic aromatic hydrocarbons (PAHs), and to lower degree ultrafine particles, inorganic and organic carbon fraction of PM, but did not influence NOx, formaldehyde, and gas‐phase PAHs. Measurements directly above the flame showed empirical evidence of short‐lived strong emission peaks of soot particles. The results show the importance of including the entire burn time of candles in exposure assessments, as their emissions can vary strongly over time. Preventing stressed burning of candles can reduce exposure to pollutants in indoor air.

Impact of Indoor Air Pollution in Pakistan—Causes and Management

“…Human activities, construction m door air have been major sources of indoor pollution [22][23][24]. The resul tants have been identified as PM, noxious gases, bacteria, fungi, insects major indoor toxic gases involve the oxides of carbon (COx) (carbon m carbon dioxide (CO2)) [28], oxides of nitrogen (NOx) (nitric oxide (NO oxide (NO2)) [29,30], oxides of sulfur (SOx) (sulfur dioxide (SO2)) [31], P [35,36], volatile organic matter (VOC) [37], carbonaceous aerosols/biolo croorganisms (bacteria, viruses, fungi) [38][39][40], and pesticides [41]. health effects observed due to indoor pollutants comprise respiratory diseases, lung cancer, nervous system malfunctioning, kidney cancer, a diseases [42].…”

“…[25][26][27]. The major indoor toxic gases involve the oxides of carbon (COx) (carbon monoxide (CO) and carbon dioxide (CO 2 )) [28], oxides of nitrogen (NOx) (nitric oxide (NO) and nitrogen dioxide (NO 2 )) [29,30], oxides of sulfur (SOx) (sulfur dioxide (SO 2 )) [31], PM [32][33][34], radon [35,36], volatile organic matter (VOC) [37], carbonaceous aerosols/biological aerosols/microorganisms (bacteria, viruses, fungi) [38][39][40], and pesticides [41]. Common human health effects observed due to indoor pollutants comprise respiratory diseases, allergic diseases, lung cancer, nervous system malfunctioning, kidney cancer, and cardiovascular diseases [42].…”

Effects on Indoor Air Quality of Burning Chemicals (Scented Candles and Incense Sticks)

“…[5][6][7][8][9][10] 또한 향초나 인센스 스틱에는 다양한 화학물질이 함유되어 있는데, 그 중 휘발성유기화합물(Volatile Organic Compounds, VOCs)이 포함되어 있다. 11,12) VOCs은 대기 중으로 휘발되어 악 취를 유발하고, 광화학반응에 의해 오존을 발생시키며, 2차 미 세먼지의 원인물질이 되는 탄화수소 화합물을 일컫는다. 9,13,14) 대표적인 물질로는 벤젠, 톨루엔, 자일렌(m-,p-,o-), 에틸렌, 스 틸렌, 포름알데히드, 아세트알데히드 등이 존재한다.…”

“…고농도의 VOCs에 의한 인체 영향으로는 중추신경을 억제 하여 마취작용을 일으키는 급성장해와 말초신경계 및 만성적 인 신경행동학적 질병을 일으키는 만성장해로 구분할 수 있 다. 12,15,16)…”

“…12,[16][17][18] 이처럼 일상생활에서 태우는 생활화학제품을 사용함에 따 라 인체에 노출될 수 있는 PM 2.5 와 VOCs에 대한 우려가 발생 하고 있으며, 이와 관련하여 Kim과 Song (2016),19) Park 등 (2021) 20) 에서는 향초 사용시 PM 2.5 발생량을 조사하였고, Lim 과 Kim (2015) 21) 에서는 향초 사용시 VOCs 농도를 조사하는 등 선행 연구가 진행되었다. 하지만 위 3개의 연구에서 PM 2.5 와 VOCs를 동시에 측정하지는 않았으며, 향초만을 대상으로 실 험하였다.…”