Bioremediation

In 1989, NASA commissioned a landmark study aimed at finding a solution for detoxifying the air in a space station. Bill Wolverton, the environmental scientist leading the research, sought to find a method to clean the air of CO₂ and remove toxic volatile substances such as formaldehyde and benzene, which are present in many decorative elements and furniture found in homes. We find benzene in plastics, fabrics, pesticides and cigarette smoke, and formaldehyde in some cosmetics, dishwashing liquids, fabric softeners and carpet cleaners. These volatile organic compounds (VOCs) and other indoor air pollutants such as ozone have been linked to numerous acute conditions including asthma and nausea, as well as chronic diseases such as cancer and certain respiratory conditions.

Using a completely sealed one-cubic-metre chamber containing synthetic materials that released toxic volatile substances and a large number of plants, Wolverton observed, after analysing the air, that within one day the plants had eliminated the majority (70%) of the VOCs.

This capacity of plants to remove harmful compounds from air, soil and water is what is known today as phytoremediation. Since that study, now over 30 years old, research has continued and it has been found that this process involves not only the plant's leaves but also its roots and the microorganisms that inhabit the soil in which it is planted.

However, the aspect recently criticised by researchers such as Michael Waring of Drexel University is the speed at which plants are able to produce these effects. According to recent studies, plants do have this capacity to purify air, wastewater and soil, but they do so at a very slow rate. Another highly questionable aspect of the original study is that it extrapolated to everyday life an experiment conducted under artificial conditions — namely the complete sealing of the chamber. Waring and colleagues concluded that a very large number of plants per cubic metre would be needed to produce a measurable improvement in indoor air quality, and that the ventilation rate of a normal home should be considered a very important variable.

This is not to say that all the possibilities offered by bioremediation should not continue to be explored. It is a field with great potential, and one in which many companies in the United States and Japan are currently investing. However, we must be cautious when extrapolating laboratory research results to real life.

Filling your office or home with plants will make you more productive or help you feel more relaxed and happy, but it will not make you breathe purer air. What is important is to ventilate your living spaces properly — in the mornings and before going to bed — in order to eliminate the carbon dioxide that accumulates during the day or night in the room. It is also important to avoid as much as possible cleaning products that release volatile organic compounds, replacing them with less aggressive alternatives.

HAUS buildings are fitted with a double-flow ventilation system that delivers clean, fresh air throughout the day and night, ensuring that the spaces where you work and live are truly healthy environments.

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