Public Health insights can reduce PM2.5 count in one move

The issue of air pollution is constantly on people’s radars, and many of them would put an air purifier or houseplants indoors to improve the air quality.

According to the latest research from Professor Kai-Jen Chuang (莊凱任) and Associate Professor Hsiao-Chi Chuang (莊校奇) at the College of Public Health, TMU, the concentration of PM2.5 aerosol particles that makes up part of air pollutants is lower in homes with potted plants compared to those without, and it can vary by as much as 1.29-fold. This research has been published in Environment International.

The research points out that those with indoor houseplants have better air quality compared to average homes, especially during summer. Associate Professor Hsiao-Chi Chuang (莊校奇) says that the data showed plants in homes offered a degree of help in improving the air quality. Previous research also showed that broad-leafed plants can filter out and break down PM2.5 particles, acting as a natural air purification device.

Professor Kai-Jen Chuang (莊凱任) says that this research observed and monitored 60 families, of which 30 homes had 8-21 houseplants, while the remaining 30 had two or fewer houseplants. The statistics showed 52.3% of the homes had Epipremnum aureum, followed by 27.6% with Sansevieria trifasciata, and 15.7% had Hedera helix.

In addition, Associate Professor Hsiao-Chi Chuang’s (莊校奇) latest research also showed that exposure to PM2.5 particulate matters in the environment will worsen short-term memory, cause changes to cerebral structures and lead to neural inflammatory responses. The results have been published in the international journal Particle and Fibre Toxicology. The research looked at exposing adult rats to PM1 particulate matters found in the Greater Taipei Area for 3 months, which lead to the worsening of the rats’ short-term memories. What was worth noting, was NMRI analysis of the rat’s cerebral structure found that 3-month and 6-month exposure to PM1 particulate matters led to increase in the rat’s brain size and hydrocephalus, which are all related to the brain’s oxidative stress and inflammatory responses, and may increase the risk of neurodegenerative disease.

Director Kang-Yun Lee (李岡遠) of the Division of Thoracic Medicine at TMU Shuang Ho Hospital (雙和醫院) says that PM2.5 particles is a danger to health, able to affect the respiratory system as well as cardiovascular diseases, and long-term exposure to PM2.5 environment can even lead to greater risk for tumors, thus having houseplants at home would be beneficial to health. Professor Kai-Jen Chuang (莊凱任) indicated that numerous local and overseas research has showed certain houseplants can effectively break down formaldehyde and other volatile organic chemicals. This new research provides further proof that indoor houseplants also help in reducing PM2.5 concentrations in the air.

What is worth noting is that although the PM2.5 concentration is lower in homes with houseplants, once the summer temperature climbs above 30C, the concentration of isoprene and ozone in the air of homes with houseplants also rose, where the average concentration of ozone in the summer reached 59.7ppb, compared to the average concentration of 36.2ppb in homes without houseplants. The main cause for this is that isoprene will combine with common air pollutants to create ozone, so people need to be aware of the indoor temperature and ventilation of houseplants.

Houseplants are a smart way to improve indoor air quality

In fact, ozone is not only produced through phytoncide undergoing photochemical reactions; printers and photocopiers can also produce ozone. Thus any indoor environment with this equipment should be well ventilated. Director Kang-Yun Lee (李岡遠) says ozone does not exist due to exhaust from factories or vehicles, but is generated from the environment after photochemical reactions. People can think about how to control this; for example, many buildings utilize glass curtains and French windows which allow large amounts of light, and improving insulation will reduce formation of ozone.