Office plants – your health resource at your workplace

Houseplants may conjure up thoughts of pleasant decor, added elements of design recommended by your favourite TV show, or background noise to an already busy home.

How often do you think of your plants as a health supplement? When was the last time you

thanked your plants for filtering your air or reducing your stress? Or when did you last look at your philodendron and thank it for helping you concentrate and focus for a task?

Plants are some of the healthiest additions you could add to your office, and you don’t even have to ingest them. The simple act of having plants can help you heal more quickly, focus more intently, reduce stress levels, boost the immune system, reduce depression levels, and more. And

it’s possible to reap these immense health benefits just by having these seemingly innocuous displays of nature sit in your office, doing absolutely nothing but look pretty.

Improved Air Quality

Do you want to look younger, sleep better, reduce your stress, lower your depression, heal faster, and improve your focus? If you answered yes, there’s good news.

The first major benefit you receive from plants is better air. Yes, plants are able to filter contaminants and toxins out of our air, making us healthier and preventing costly long-term illnesses from appearing in the first place.

Humans spend a whopping 90 percent of their lives indoors, mostly in their homes and offices, continually breathing in recycled air. Our cultural allergy to the outdoors is providing us with a unique experience of a myriad of physical reactions to our dirty interiors. The air you breathe inside your home could be a contributing factor to a variety of illnesses, and more damaging than

the air in the most polluted cities. From frequent colds to dry skin, chronic cough, eye irritation, and memory lapse, the stagnant particles we call “air” are making us sick. There’s even a term for this phenomenon called “sick building syndrome”. Very original.

Air quality is pertinent to good health, and if we are continually breathing in pollutants, we’re putting ourselves at risk for serious long-term health complications such as asthma, cancer, and other chronic illnesses. While not often talked about, this public health issue is something which needs to be addressed. A good rule of thumb is to have a clean-air plant for every 25 square metre of your home.

Even NASA understood the importance of our leafy friends, conducting a study in 1989 examining their ability to clean and filter the air for space stations, and what they found was impressive. The research demonstrated that common houseplants not only recycle our air, absorbing the carbon

dioxide we breathe out while releasing precious oxygen back into our atmosphere, but they also have the ability to filter out carcinogenic chemicals, such as benzene, formaldehyde, trichloroethylene, ammonia, and xylene.

Plants absorb carbon dioxide and also particulates in the air, which are then processed into the life-affirming oxygen we breathe in, but that’s not the whole story. There are also microorganisms in the potting soil that are responsible for a big part of this cleaning effect. You heard it, the dirt that

we so often avoid touching is the very dirt that is keeping us healthy and saving our lungs from toxic compounds. The leaves, roots, soil, and all the microorganisms of a plant have a part to play in their ability to clean our precious air, and every plant we place inside our airtight homes is another win for our air quality. Forget cardio, bring me more phytoncides! For those of us who don’t have regular access to a forest for a daily hike, we can still get the benefits of microbes from our indoor gardens. High five!

The most common air pollutants in office environment

Benzene: A widely known carcinogen often found in gasoline fumes, cigarettes, and car exhausts, and used in industries related to plastic, oil, gasoline, rubber, and more. What’s startling is that benzene is found at high levels in indoor air, which could be from car exhaust, paints, adhesives, and

even in your new furniture. The more time you spend indoors could equal the more exposure you have to benzene. Exposure to benzene is a major public health concern, citing exposure can lead to cancer and aplastic anaemia.

Formaldehyde: Another widely known chemical, this colourless, flammable, strong-smelling gas is found in a variety of building materials. Often used in glues, adhesives, wood products such as particleboard, plywood, and fibreboard; and fungicides, germicides, and disinfectants. The Environmental Protection Agency states that formaldehyde can cause short-term irritations of the skin, eyes, nose, and throat, and high levels of exposure may cause some types of cancers.

Trichloroethylene: Another chemical commonly used as an industrial solvent. Chronic exposure has been linked to cancer and other chronic illnesses.

Ammonia: One of the most widely produced chemicals, ammonia is actually found in nature and is produced in the human body. Often found in fertilizer and the manufacturing of plastics, explosives, fabrics, pesticides, dyes, and other chemicals, you’re most likely exposed to it via your household or office cleaning solutions. Overexposure to this chemical can cause irritation, burns. eye, nose, and throat irritation, and lung damage.

Xylene: Widely used as a chemical solvent, cleaning agent, and paint thinner, xylene has been shown to cause irritation to the mouth and throat, dizziness, headache, confusion, and liver and kidney damage. Plants may appear docile, but their ability to filter out harmful substances and chemicals from your air proves that their strength is more than meets the eye. According to NASA, some houseplants are better than others at cleaning and filtering our air.

As an example, if we look at one plant species and how many chemicals it removes from a fixed indoor volume of air within 24 hours, we can see the following:

Dracaena fragrans Janet Craig with a total leaf surface of 15,275 cm2 removed per medium sizes plant:

- 18,330 micrograms of Trichloroethylene – 17.5%

- 25,968 micrograms of Benzene – 79.1%

- 48,880 micrograms of Formaldehyde

Author of technical contribution: Willard L. Douglas, Ph.O

How much oxygen does a houseplant give off in a day?

The amount of oxygen that a plant produces is much more difficult to calculate because it depends on many variables. Plants produce oxygen as a byproduct of making sugars, which is their energy source. Slow growing plants need much less sugar than fast growing plants, and therefore produce much less sugar and oxygen.

Photosynthesis converts CO2 to O2, but plants also respire. During respiration they convert sugar and oxygen into CO2 and water. This is the reverse of photosynthesis, and it happens in all cells, all of the time, day and night. Respiration reduces the net amount of oxygen plants produce, especially at night when there is no photosynthesis.

So, houseplants can’t supply all the oxygen we need, but do they increase the oxygen level?

The maximum amount of photosynthesis varies between 0.6 and 40 µmol CO2 fixed per square metre of leaf per second.

For every 150 grams of plant tissue grown, 32 grams of oxygen are released. This is 22 liters of oxygen under normal temperature and pressure.

If we had enough plants in a room to use up all of the CO2 and convert it to oxygen, the oxygen levels would increase from 20.95% to 21%. This increase is difficult to detect and would have no effect on humans. Keep in mind that this increase is the maximum increase possible and assumes plants would use all the CO2 available. In real life the increase is even less.

So how much oxygen does a plant produce?

The average indoor plant will produce 900 ml of oxygen/day or 27 litres of oxygen a month, if we say the average growing plant has 15 leaves and each leaf gives an average of 5ml oxygen/hour for 12 hours a day. It will take the average person around 3 minutes to consume that amount of oxygen.

A typical human needs about 50 litres of oxygen per hour. That translates to 10,000 office plants leaves, or maybe 500 to 1000 houseplants to support one human

The effect on oxygen levels is therefore not very significant. There is a much greater impact on CO2 levels. Still, with respect to the effect on indoor air quality, the most important influence of plants is the removal of a class of pollutants known as volatile organic compounds (a.k.a. 'fumes') that include formaldehyde.

Top three oxygen producing plants:

1. Sprouts: If you grow your own sprouts for food (especially sweet pea sprouts, buckwheat sprouts and sunflower sprouts) you will have a fantastic mini greenhouse effect in your living space.

2. Snake Plant a.k.a. Mother-In-Law’s Tongue a.k.a Sansevieria: Of all the different oxygen producing plants, this one is unique since it converts a lot of CO2 (carbon dioxide) to O2 (oxygen) at night, making it ideal to have several in your bedroom. 6-8 waist high plants are needed per person to survive if there is no air flow

3. Areca Palm - Dypsis lutescens: This plant removes xylene and toluene from the air, but also happens to convert a lot of CO2 (carbon dioxide) to O2 (oxygen) during the daytime.

Other high producing Oxygen plants:

Nephrolepis exaltata

Philodendron scandens

Sansevieria trifasciata

Chlorophytum comosum

Aglaonema modestum

Epipiremnum aureum

Conclusion:

We can say that the oxygen produced by office plants is not significant but their presence in the office environment has a great contribution to a healthy and more friendly environment.

Low light requiring office plants, along with activated carbon plant filters, have demonstrated the potential for improving indoor air quality by removing trace organic pollutants from the air in energy efficient buildings. This plant system is one of the most promising means of alleviating the “sick building syndrome” associated with many new, energy efficient buildings. The plant root-soil zone appears to be the most effective area for removing volatile organic chemicals. Therefore, maximizing air exposure to the plant root-soil area should be considered when placing plants in buildings for best air filtration.

Research from the Norwegian University of Life Sciences and Uppsala University in Sweden found that the mere presence of plants in an office or home increased levels of happiness, reduced stress and fatigue, and reduced the amount of sick leave workers took. Another study found that indoor plants may reduce psychological stress by suppressing the sympathetic nervous system (our fight-or-flight response), making us less stressed and our bodies more relaxed.

Credits for studies presented here: