The impact of plug-in fragrance diffusers on residential indoor VOC concentrations

Plug-in fragrance diffusers are one of myriad volatile organic compound-containing consumer products that are commonly found in homes. The perturbing effects of using a commercial diffuser indoors were evaluated using a study group of 60 homes in Ashford, UK. Air samples were taken over 3 day periods with the diffuser switched on and in a parallel set of control homes where it was off. At least four measurements were taken in each home using vacuum-release into 6 L silica-coated canisters and with >40 VOCs quantified using gas chromatography with FID and MS (GC-FID-QMS). Occupants self-reported their use of other VOC-containing products. The variability between homes was very high with the 72 hour sum of all measured VOCs ranging between 30 and >5000 mu g m(-3), dominated by n/i-butane, propane, and ethanol. For those homes in the lowest quartile of air exchange rate (identified using CO2 and TVOC sensors as proxies) the use of a diffuser led to a statistically significant increase (p-value < 0.02) in the summed concentration of detectable fragrance VOCs and some individual species, e.g. alpha pinene rising from a median of 9 mu g m(-3) to 15 mu g m(-3) (p-value < 0.02). The observed increments were broadly in line with model-calculated estimates based on fragrance weight loss, room sizes and air exchange rates.

Automated summary

Plug-in fragrance diffusers, commonly found in homes, were evaluated for their effects on indoor air quality. Air samples were taken from 60 homes in Ashford, UK, with the diffuser on or off. The concentrations of volatile organic compounds (VOCs) were measured using gas chromatography. The study found that homes with low air exchange rates and using the diffuser had higher concentrations of fragrance VOCs.