Meanwhile, indoor air pollution is a constant problem and a threat to human health. So looking further into the idea of how houseplants can fend off the potentially harmful effects of volatile organic compounds (VOCs), a main category of air pollutants, a team of researchers have made some new discoveries. They found that certain plants are better at removing specific compounds from the air – this is especially meaningful for indoor air, as studies have shown that interior air can have three to five times more pollutants than outside.
"Buildings, whether new or old, can have high levels of VOCs in them, sometimes so high that you can smell them," says Vadoud Niri, Ph.D., leader of the study.
VOCs include things like acetone, benzene and formaldehyde – they are emitted as gases and can cause short- and long-term health effects. They are invisible to the eye and come from common things many of us have around the house, things as innocent-seeming as furniture, copiers and printers, cleaning supplies and even dry-cleaned clothes.
"Inhaling large amounts of VOCs can lead some people to develop sick building syndrome, which reduces productivity and can even cause dizziness, asthma or allergies," Niri says. "We must do something about VOCs in indoor air."
Since the NASA research in the 1980s, a number of studies have looked into how plants work their magic on air quality, but most of the research has looked at the removal of single VOCs by individual plants from the air; Niri wanted to compare the efficiency of simultaneous removal of several VOCs by a number plants. You can see more on how the research was conducted in the video below, but basically he and his team from the State University of New York at Oswego used a sealed chamber in which they monitored the VOC concentrations over several hours with and without a different type of plant. For each plant they measured the VOCs the plants took up, how quickly they removed these VOCs from the air, and how much of the VOCs were removed altogether. They employed five plants and eight VOCs.
1. Jade plant
2. Spider plant
4. Caribbean tree cactus
They found that all of the plants were good at removing acetone, but the dracaena plant took up the most, around 94 percent of the chemical. The bromeliad plant was great at removing six of the eight VOCs, taking up more than 80 percent of each over a 12-hour sampling period. Likewise, the jade plant was very good for toluene.
During a press conference for the 252nd National Meeting & Exposition of the American Chemical Society, which is where the research has been presented, a reporter asked if this made the plants sick. Niri replied that his 11-year old daughter had wondered the same, asking if this wasn’t abusing the plants. While Niri assured that low-levels of VOCs wouldn’t harm the plant, it’s a great reminder to respect these green leafy organisms who work so tirelessly on our behalf.
Photos by Tanaka Juuyoh and Cori Redford, Flickr