Indoor Air Quality and VOCs

Indoor air quality (IAQ) refers to the chemical, biological and physical composition of air inside buildings, where adults in industrialised countries spend ~90% of their time. Key pollutants include volatile organic compounds (VOCs) such as formaldehyde, benzene and toluene from furniture, paints, cleaning products and combustion; nitrogen dioxide (NO₂) from gas cooking; and ultrafine particles from cooking, candles and printers. Elevated VOC and CO₂ levels impair higher-order cognition: the 2016 'COGfx' controlled-exposure study found cognitive function scores were 61% higher in low-VOC green-building conditions and 101% higher with enhanced ventilation, compared to conventional offices. Chronic exposure is linked to Sick Building Syndrome, asthma exacerbation and adverse cardiovascular outcomes. The WHO 2010 indoor air quality guidelines set health-based limits for selected pollutants; in Germany, the Umweltbundesamt issues guide and intervention values for indoor VOCs.