Circadian Environments

Science · Core 7

Materials

What a room is made of ends up in its air and dust.

Finishes, furniture and everyday products release chemicals into indoor air and settle into household dust. Choice and ventilation both matter.

Why it matters

Building materials, furnishings and household products emit volatile organic compounds (VOCs), especially when new. Other chemicals, such as flame retardants and plasticisers, are less volatile and collect in dust, which people then breathe, swallow or absorb through the skin.

What the research shows

Formaldehyde. Pressed-wood products, some adhesives and finishes are well-documented indoor sources of formaldehyde 1. It is one of the priority hazards identified across measurements in homes 2.

Chemicals in dust. A meta-analysis of household dust found phthalates, replacement flame retardants, PFAS, synthetic fragrances and environmental phenols consistently present, and many share hazard traits such as reproductive and endocrine toxicity 3.

Cleaning products. In a 20-year European study, women who cleaned at home or worked as cleaners had a faster decline in lung function than women who did not, and the use of cleaning sprays was associated with faster decline 4.

VOCs and thinking. In a controlled office study, lower VOC levels were associated with better cognitive test scores 5.

What can be done

Choose low-emission products where they are available: low-VOC paints and adhesives, low-formaldehyde boards, and solid or certified timber. Ventilate well during and after renovation, and let new furniture air out. Damp-dust and use a vacuum with a HEPA filter. Use fewer sprays and fragrances. In older homes, have suspect materials tested for asbestos by a licensed assessor before any renovation.

Durable, repairable materials that last also reduce waste. See Sustainability.

How we assess it

We measure total VOCs and formaldehyde, review recent renovations, furniture and products, and help specify materials for upcoming work.

Evidence at a glance

  • Well supported

    Pressed-wood products and some finishes release formaldehyde indoors. 1

  • Reasonable

    Regular use of cleaning sprays may harm long-term lung health. One large cohort, consistent with other findings. 4

  • Reasonable

    Choosing low-emission products reduces exposure. Emissions data are clear; health benefits in homes are inferred.

General information only, not medical advice. How we grade evidence.

References

  1. Salthammer T, Mentese S, Marutzky R. Formaldehyde in the indoor environment. Chem Rev. 2010;110(4):2536-72. doi.org/10.1021/cr800399g · PubMed 20067232
  2. Logue JM, McKone TE, Sherman MH, Singer BC. Hazard assessment of chemical air contaminants measured in residences. Indoor Air. 2011;21(2):92-109. doi.org/10.1111/j.1600-0668.2010.00683.x · PubMed 21392118
  3. Mitro SD, Dodson RE, Singla V, et al. Consumer product chemicals in indoor dust: a quantitative meta-analysis of U.S. studies. Environ Sci Technol. 2016;50(19):10661-10672. doi.org/10.1021/acs.est.6b02023 · PubMed 27623734
  4. Svanes Ø, Bertelsen RJ, Lygre SHL, et al. Cleaning at home and at work in relation to lung function decline and airway obstruction. Am J Respir Crit Care Med. 2018;197(9):1157-1163. doi.org/10.1164/rccm.201706-1311OC · PubMed 29451393
  5. Allen JG, MacNaughton P, Satish U, et al. Associations of cognitive function scores with carbon dioxide, ventilation, and volatile organic compound exposures in office workers: a controlled exposure study of green and conventional office environments. Environ Health Perspect. 2016;124(6):805-12. doi.org/10.1289/ehp.1510037 · PubMed 26502459