What’s in the air?

Dust art: Rust particles collected from Taipei homes.

An analysis of vacuum dust bags says a lot about indoor pollution.

Every day, we are surrounded by dust – microscopic particles that fall from the sky or are generated from pollution.

While the quality of our outdoor air continues to be a global environmental and health concern, little attention is paid to our indoor air. Yet, the indoors are where we spend most of our time.

A recent study, termed The Invironment Project, sheds light on the pollutants that swirl within homes and offices in different countries. It was initiated by home appliance maker Electrolux to turn what is invisible in homes and buildings, visible.

Indoor air quality surveys were done in cities like Los Angeles, Sao Paolo, Stockholm, Singapore, Paris, Seoul and Taipei. In each city, two homes were vacuumed.

The Swedish University of Agricultural Science senior scientist Dr Gulaim Seisenbaeva says particle research is commonly focused on particle measurement and size, but this study looked at what made up the particles.

The analysis, using an elemental detector, found traces of the skeletons of marine organisms in Los Angeles. In Taipei, it was gypsum, which is the traditional and most widely used coagulant to produce tofu.

“This result is proof that the external environment can affect the indoors as 58% of the particles contained in the vacuum bags originated from outdoor sources. A dust bag’s contents say a lot. There were unexpected findings such as bismuth traces from hunting projectiles and common materials such as plastic and concrete,” says Seisenbaeva.

Bismuth, a chemical element, is regarded as an unexpected find because it is not present in common household products nor the environment, but used in Sweden in the production of hunting pellets and some alloys in electronics.

As for the other cities, their revelations are no less interesting and mind-boggling: Paris was found to contain lead particles used in paint in older buildings; Sao Paolo in Brazil has bauxite, the main source of aluminium and for which the country is the world’s top producer; and Stockholm has dolomite, a mineral used to cover walking paths there. The homes in Singapore has low levels of mineral material from the outdoors, a result of its wet climate hindering distribution of dust by the wind.

Silicate particles from Stockholm.

But what calls for critical attention are soot particles and electronic capacitors which contain heavy metals such as zirconium, niobium, cadmium and barium – breathing these in can result in allergies and respiratory damage. Also disturbing is the discovery of a highly lethal mix of thallium and copper in one of the dust bags; Thallium has a notorious reputation in history as a murder weapon ingredient.

“What is conclusive is that the indoor environment is dependent on the immediate surroundings and factors such as proximity to traffic and local climatic conditions,” says Seisenbaeva.

While we might not like to admit it, it is often us and our lifestyle such as habits, preferences, activities and personal possessions that determine the quality of our indoors, and subsequently, the dust bag. For instance, a pet will leave traces of excrement, wearing shoes at home will leave some dirt, and simply hoarding stuff will breed mites.

Swedish University of Agricultural Science senior scientist Dr Gulaim Seisenbaeva analysed bags of vacuumed dust to identify indoor pollutants.

Electrolux sustainability affairs director Cecilia Nord says the study will provide insights into what will be demanded of future generations of vacuum cleaners. She says in an effort to translate what is invisible to the naked eye, visible, elements gathered from the analysis were enlarged into a series of photographs. The magnified versions of various particles sucked up by the vacuum cleaners showed up in beautiful shapes and patterns, resembling abstract art pieces.

“During the result evaluation, we realised that the tiniest of particles looked immensely intriguing in large sizes. It adds an emotional impact to an otherwise very rational aspect of the findings,” says Nord. The “dust art” collection is now on display via Pinterest.

What can you do to rid as much dust as possible from your indoor environment? Here are some tips shared by Electrolux:

> Vent your home by opening a window when it rains or after. This will refresh the indoor air and reduce the concentration of particles.

> Keep houseplants. They can filter common volatile organic compounds.

> Your shoes are often the link between indoor and outdoor environments. So, take them off before entering the home to prevent polluting particles from building up indoors.

Fluff and carbon in Stockholm.

Of course, it pays to consider our everyday habits and activities and if, need be, reinvent our lifestyle once the pollution sources are identified. And lastly, vacuum more often – that is the most direct way to reduce contaminants.

Seisenbaeva cautions that the age and quality of vacuum cleaners can make a significant difference. Old vacuum cleaners cannot contain dust and particles as efficiently as modern ones.

“Earlier studies by the American Chemical Society shows that older vacuum cleaners may in fact, contribute to indoor air pollution, with the release of bacteria and dust particles that can spread infections and trigger allergies.”