Is the green radish reliable in removing formaldehyde? I bought 50 pots to test it, and the results were somewhat surprising

When it comes to removing formaldehyde from a new house, the first thing that comes to mind for many people is the green ivy! I feel uneasy if I don’t buy a few potted plants to put at home after the renovation.

Plants do have the effect of removing formaldehyde. From the earliest NASA to the National Indoor Environment Committee, there are relevant records in many literatures.

Source: "Screening of indoor plants for efficient formaldehyde purification and research on their purification kinetics"

But! Don’t rush to buy green plants!

The formaldehyde removal efficiency is affected by factors such as plant species, culture medium, temperature, light intensity, leaf water transpiration rate, resistance of pollutants entering the leaves, etc. In addition, the test environment in the literature is generally a 1m³ sealed cabin, and a one-time formaldehyde solution is used as the pollution source, which is different from our daily living environment.

So, this time we decided to simulate a normal home environment, use panels as the source of formaldehyde release, and test the actual formaldehyde removal effect of plants.

01 Is it reliable to use green radish to remove formaldehyde? I searched for green plants and found that green radish ranked first in terms of its formaldehyde removal effect. So we immediately contacted a flower shop and bought 50 pots of green radish and moved them to the company's experimental cabin.

In order to be close to the real family living conditions, we chose an experimental cabin with an area of ​​12㎡ and a floor height of 2.5m as the test site, which is close to the size of a child's room. The formaldehyde release source did not use the formaldehyde solution commonly used in the laboratory, but used 8 density boards (cabinets contributed by colleagues). 10 pots, 20 pots, and 50 pots of green radish were placed respectively, and the formaldehyde trend in the cabin was monitored for 24 hours.

The results showed that within the initial 2 hours of sealing, each group of plants had no effect, but as the sealing time increased, the effect of green radish on formaldehyde removal began to show.

How many pots of green ivy are needed to remove formaldehyde in a small child's room?

Obviously, 10 pots of green radish are far from enough. After 24 hours, the indoor formaldehyde concentration barely dropped to 0.180 mg/m³.

Moreover, in the first 12 hours, the 10 pots of green ivy not only failed to remove formaldehyde, but also increased the indoor humidity due to the transpiration of the leaves, which promoted the release of formaldehyde from the boards, resulting in the indoor formaldehyde concentration being higher than when no green ivy was placed.

Only after 50 pots of green radish were placed, the plant's formaldehyde removal effect could be clearly seen, and after 6 hours, the formaldehyde concentration basically stopped increasing and the concentration was balanced at 0.06mg/m³.

That is to say, planting green ivy can indeed remove formaldehyde, but the prerequisite is that you turn your home into a forest!

A 12㎡ child's room requires 50 pots of green ivy. If your home is 100㎡, according to this calculation, you will need to fill your home with 400 pots of green ivy to reduce the formaldehyde concentration in the room to a lower level.

50 pots of green ivy have brought the humidity in the experimental chamber to close to 90%RH.

Even if you don't mind having nowhere to step in your home, the humidity of 400 pots of green radish will make you question life! I refuse to live in such humidity!

02 It turns out that there are others who can remove formaldehyde. At the beginning of the article, we mentioned that the effect of plants on formaldehyde removal is also related to the "culture medium", which generally refers to the soil. So the question is, since the soil for growing plants is loose and porous, will it also absorb formaldehyde?

Without further ado, I immediately brought the green radish and started cutting it (we then replanted the cut green radish in hydroponics).

The results were a bit surprising. Whether it was 20 pots of soil and 20 pots of green ivy, or 50 pots of soil and 50 pots of green ivy, the removal rate of green ivy for indoor formaldehyde was only 12% (20 pots) and 17% (50 pots) more than that of soil.

In other words, if it is just the plant itself, the removal rate of indoor formaldehyde is not high. In the role of green radish in purifying indoor formaldehyde, the soil can be said to have made an indispensable contribution.

Two experiments were conducted, which proved that instead of filling a room with green ivy to remove formaldehyde, it is better to dig some soil downstairs. This is more economical and the humidity is not so high.

However, we really don’t recommend you to do this. Not only may it absorb and release the substance twice, but it will also be very troublesome to clean up later. The most important thing is that opening windows for ventilation will have a better effect in removing formaldehyde. This is the most economical and effective method!

Plants are placed in the house for beautification, so there is no need to have too many "unreasonable expectations" for them.