Visualising household air pollution: Colorimetric sensor arrays for monitoring volatile organic compounds indoors

PLoS One. 2021 Oct 6;16(10):e0258281. doi: 10.1371/journal.pone.0258281. eCollection 2021.

Abstract

Indoor air quality monitoring as it relates to the domestic setting is an integral part of human exposure monitoring and health risk assessment. Hence there is a great need for easy to use, fast and economical indoor air quality sensors to monitor the volatile organic compound composition of the air which is known to be significantly perturbed by the various source emissions from activities in the home. To meet this need, paper-based colorimetric sensor arrays were deployed as volatile organic compound detectors in a field study aiming to understand which activities elicit responses from these sensor arrays in household settings. The sensor array itself is composed of pH indicators and aniline dyes that enable molecular recognition of carboxylic acids, amines and carbonyl-containing compounds. The sensor arrays were initially deployed in different rooms in a single household having different occupant activity types and levels. Sensor responses were shown to differ for different room settings on the basis of occupancy levels and the nature of the room emission sources. Sensor responses relating to specific activities such as cooking, cleaning, office work, etc were noted in the temporal response. Subsequently, the colorimetric sensor arrays were deployed in a broader study across 9 different households and, using multivariate analysis, the sensor responses were shown to correlate strongly with household occupant activity and year of house build. Overall, this study demonstrates the significant potential for this type of simple approach to indoor air pollution monitoring in residential environments.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Air Pollution, Indoor / analysis*
  • Colorimetry*
  • Family Characteristics
  • Principal Component Analysis
  • Volatile Organic Compounds / analysis*

Substances

  • Volatile Organic Compounds

Associated data

  • figshare/10.6084/m9.figshare.16608613

Grants and funding

E.D. was supported by funding from the European Union’s Horizon 2020 Research and Innovation Programme (https://ec.europa.eu/programmes/horizon2020/) under the Marie Skłodowska-Curie and by funding from Science Foundation Ireland (SFI) (https://www.sfi.ie/) under Grant Number: SFI/12/RC/2289_P2, co-funded by the European Regional Development Fund. K.H. and R.L. were supported by the Academy of Finland (REMEDIAL consortium, grant no: 296724) and University of Eastern Finland (UEF). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.