Indoor Air Quality: The Importance of Polluting Sources in Buildings

Currently, the time we spend inside buildings is even greater than the 90% recorded in recent decades, a direct reflection of the periods of confinement imposed by the economic situation. In addition, the variability of indoor spaces we frequent is much smaller, being reduced to our homes and workplaces, which in some cases even coincide. Therefore, populations tend to spend more time exposed to the same pollutants, which reinforces the importance of having indoor air as little polluted as possible.

Without knowing it, we fill our homes with products that emit polluting substances identified as the cause of various health problems, especially those related to the respiratory system, such as volatile organic compounds (VOC) and semi-volatile (COSV), formaldehyde and particulate matter.

Construction materials are the most commonly associated with this risk, since they represent a greater emission area, leading to their having already been subject to regulation in many European countries, although not in Portugal. However, we can already find in our country building materials with labels that attest to their low emission. The European Ecolabel or the A+ label, resulting from French legislation, are the best known. INEGI's Indoor Air Quality Laboratory has over the years collaborated with several national and European industries in the characterization of construction materials, witnessing a growing interest on the part of the industry in this subject.

Several studies also demonstrate that furniture can be another of the main sources of harmful compounds such as formaldehyde and phenol, present in agglomerating resins. A considerable risk, since formaldehyde is a carcinogenic compound, suspected of being mutagenic, as is phenol, but also a skin sensitizer.

The cleaning products themselves, candles, incense and aroma diffusers have high emission rates of many compounds, some of them harmful.

In these times when, for many, the house has become an office or classroom, we have printers and computers, used more often, which also emit various pollutants, from particulate matter to VOCs, such as toluene, ethylbenzene, meta- xylene, para-xylene and styrene, commonly used as solvents in toners. In the case of computer emissions, this includes organophosphate flame retardant compounds, aromatic hydrocarbons, alkanes, alcohols, ketones and aldehydes, particularly formaldehyde, with emission rates that can be high.

Protecting health involves implementing strategies such as ventilation and source control, which must be applied together. Avoiding the use of polluting products or materials and replacing them with lower emission counterparts is an option that should be put into practice. Educating and making people aware of this topic is essential. But it is not enough to leave the responsibility to the consumer to make this selection, in a society in which usually a more polluting material is also cheaper.

The great difficulty in identifying less polluting products by reading the labels is another of the main obstacles to conscious consumption by the general population. In this sense, the influence of states would be crucial to increasing literacy in this area.

In Portugal, there was also a legislative setback with regard to Indoor Air Quality (IAQ). If in 2006 with the SCE (Building Energy Certification System) legislation, it was an example, praised internationally, by joining the QAI to the EPBD directive (European Directive on the Energy Performance of Buildings), in 2013 it dropped the obligation of audits of QAI, not taking responsibility for what happens inside the buildings.

In the exceptional period we are going through, it is imperative to reinforce the importance of Indoor Air Quality, involving all stakeholders with an active role in the direction of the health of populations.

Article originally published in the May issue of Revista O Instalador.