When you step into a freshly-painted room, you may notice a strong smell. You probably don't think much of it, but it is actually very dangerous.
The smell comes from formaldehyde, which is a toxic chemical compound. It not only irritates your respiratory system, it is also carcinogenic. Formaldehyde naturally occurs in our bodies and in the environment, but the amount is very small and is not enough to affect our health.
However, in the past few decades, the high level of indoor formaldehyde has become a concern. Indoor formaldehyde mainly comes from paint and some may come from wooden furniture glued together by adhesives.
Formaldehyde has become a common air pollutant. Some companies produce formaldehyde-free paint that emphasises the product is safe and without the distinctive smell. But some people still choose the ones containing formaldehyde as they are cheaper.
The question is: are there any affordable options that reduce indoor formaldehyde?
Plants are thought of as "air purifiers" because they can absorb carbon dioxide and release oxygen. According to a Nasa Clean Air Study, the air-purifying functions of plants are more effective than we might think. The study suggests that plants can reduce some air-borne toxic agents, including formaldehyde.
It seems that using plants to absorb formaldehyde is the obvious solution, with the added benefit that plants brighten up any room. But with so many plants on the market, which ones should we choose? Is the biggest the best? How many plants do we need? As engineering students, we are also curious about the science behind this and want to know whether the absorption harms the plants.
Formaldehyde is absorbed by the leaves and roots of a plant. The formaldehyde isn't harmful to the plant if the concentration levels don't exceed safety levels. Big leaves may be helpful, but different species of plants have different abilities to absorb formaldehyde.
Over the past three months, we have tested the ability of plants to absorb formaldehyde. Ivy, lucky bamboo and pothos were chosen. They are common indoor plants because they are cheap and easy to look after.
Our experiment found that all of them are effective at absorbing formaldehyde.
At the end of the experiment, they had reduced the concentration of formaldehyde to one-fifth of the original. Of the three plants used, ivy was the best for absorbing formaldehyde as it reduces the chemical at a faster rate.
The experiment not only provided us with answers, but also taught us to respect life in all forms.