Indoor Air Pollution of Volatile Organic Compounds

Mosquito-repellent incense (MRI) is a widely used product in the household. Although the quality of MRI has been strictly managed, it still has certain health effects in practical use. This study investigated the level of volatile organic compounds (VOCs) in MRI smoke and its removal ability by photocatalysis. An online survey was conducted using Google form to select three typical types of MRI which are the most popular use in Vietnam (i.e., MOSFLY, RAID, and JUMBO VAPE) as well as their use level and condition. These types of MRIs were then burnt in a normal room for 8 h to determine the level of air pollution emission. Results from room test show that the tVOCs concentration emitted from one of the MRIs was as high as 1621 ppb, which was the highest pollution level among the three MRIs tested. This type of MRI was then employed as VOCs pollutant source for testing the treatment ability of a photocatalytic equipment in a closed chamber. The experimental treatment of emitted VOCs by the photocatalytic treatment equipment showed that titania nanotubes (TNTs) modified with metal salt and heat treatment achieved high removal efficiency. It has reached indoor air standards of ≤ 490 ppb after 180 min of treatment with an input concentration of about 1,600 ppb. By changing the conditions of TNTs modification and operation conditions, the highest treatment efficiency was achieved with 2 g of zinc doped TNTs at a Zn/Ti molar ratio of 0.5%, calcined at 500 oC, in which the treatment to meet the standard reached the shortest treatment time. The results in this study indicate that burning MRI could cause indoor air pollution that may affect human health and photocatalysis is a potential technology for treating VOCs from indoor MRI burning.

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Ultra-High Response Detection of Alcohols Based on CdS/MoS2 Composite

Nanoscale Research Letters ◽

10.1186/s11671-021-03647-3 ◽

2022 ◽

Vol 17 (1) ◽

Author(s):

Lei Liu ◽

Weiye Yang ◽

Hui Zhang ◽

Xueqian Yan ◽

Yingkai Liu

Keyword(s):

Air Pollution ◽

Organic Compounds ◽

Indoor Air ◽

Indoor Air Pollution ◽

Limit Of Detection ◽

Isoamyl Alcohol ◽

Synergy Effect ◽

Volatile Organic ◽

Basic Source ◽

Response Detection

AbstractHybrid CdS/MoS2 with branch and leaf shaped structures are successfully synthesized by hydrothermal method. It is applied to detect volatile organic compounds, a basic source of indoor air pollution with deleterious effects on the human health. The sensor based on CdS/MoS2 displays an outstanding response to alcohols among numerous gases. Their response to 100 ppm ethanol and isopropanol reaches 56 and 94, respectively. Benefiting from the dendrite-like biomimetic structure and synergy effect of CdS and MoS2, the sensor exhibits higher response than traditional gas sensor. For multiple alcohols, the limit of detection reached ppb level. In addition, by comparing the response of ethanol, isopropanol, isoamyl alcohol and their mixtures with acetone and methanal, a strong resistance interference is observed. This work proved that the modified detector holds broad promise in the detection of alcohols.

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Assessment of residential exposure to Volatile Organic Compounds (VOCs) and Carbon Dioxide (CO2)

Global NEST Journal ◽

10.30955/gnj.002278 ◽

2018 ◽

Vol 19 (4) ◽

pp. 726-732

Keyword(s):

Volatile Organic Compounds ◽

Organic Compounds ◽

Indoor Air ◽

Indoor Air Pollution ◽

Consumer Products ◽

Air Pollutant ◽

Outdoor Environment ◽

Residential Exposure ◽

Volatile Organic ◽

Potential Sources

There is increasing concern about indoor air pollution worldwide due to its adverse health effects. One of the predominant indoor air pollutant groups is assumed to be volatile organic compounds (VOCs), including a variety of hydrocarbons with different functional groups. Among VOCs, some species have carcinogenic effects, and some are widely used in many consumer products. CO2 is assumed to be an indicator of ventilation adequacy. Thus, elevated indoor CO2 levels are linked with the discomfort level of occupants. Residential exposure to VOCs and CO2 in 6 different homes located in 3 different towns in Canakkale, Turkey were assessed for about a year. Also, a home inventory was used to identify the potential sources of VOCs and CO2 as well as environmental concerns of the occupants. The highest levels of indoor CO2, total volatile organic compounds (TVOC), benzene, toluene, and xylenes were found at industrial sampling sites. A connection between aspects of the outdoor environment (i.e. availability of potential sources) and residential exposure to air pollutants was found. Also, some activities (e.g. heating fuel type, house cleaning frequency, etc.) and factors (e.g. characteristics of the outdoor environment) influenced residential exposure to VOCs and CO2.

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