Protecting Children from Indoor Air Pollution

Health inequalities, the WHO report

8 May 2025

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Transport Poverty Lab, the observatory on poverty in transport

24 May 2025

Published by Dario Dongo on 17 May 2025

Background and Method

The study was organized by the KOS Study Center – Science, Art, Society through a working table entitled 'Living and working in healthy environments: indoor air, building materials, furniture' to evaluate the evidence and discuss the impacts of indoor environments on human health and well-being. A interdisciplinary group of experts were selected based on their expertise in indoor pollution or as delegates of Italian Scientific Societies or Associations.

The research method was based on a systematic electronic search of the PubMed database using the terms 'air pollution internal' and 'air quality, internal,' limited to human studies published in English. Experts independently reviewed the texts and references, then convened to discuss and highlight key factors regarding indoor air and its impact on human health, as well as strategies to reduce pollution.

Main risk factors for indoor air pollution

The expert panel identified four primary risk factors that require further evaluation:

Poor ventilation. In poorly ventilated areas, the particulate matter levels end can be 100 times higher acceptable levels, potentially causing respiratory illnesses such as asthma, allergies and sick building symptoms. This is of particular concern in school buildings, where high concentrations of carbon dioxide indicate inadequate ventilation conditions;
Chemical substances. Indoor environments contain numerous materials with additives in paints, glues, fabrics, coatings, furnishings and electronic equipment. endocrine disruptors (ED) are particularly dangerous for children and pregnant women, as they are linked to reproductive and developmental disorders. These substances can persist in materials and indoor dust even after they have been contained;
Weather conditions. Ongoing climate change significantly affects indoor air quality, especially affecting children due to their vulnerability. Temperature and humidity can increase the risk of viral, bacterial and fungal contamination, with internal fungal contamination peaking during the summer months;
Low socioeconomic status. Poverty can exacerbate the harmful effects of air pollution on health by limitingaccess to information, treatment and other health resourcesEven in high-income countries, obsolete and inadequate housing devices are significant sources of indoor pollution.

Health impacts of indoor pollution

The experts focused on both the mortality and morbidity aspects of indoor pollution, as described below.

Mortality

Environmental pollution was responsible for approximately 9 million dead in 2019, with combined effects of environmental and domestic air pollution associated with 6,7 million premature deaths annually. Household air pollution specifically caused an estimated 3,2 million deaths annually in 2020, including more than 237.000 deaths of children under five.

Morbidity

I children are specifically susceptible to the health effects of air pollution because of their developing immune and respiratory systems. Exposure to household air pollution nearly doubles the risk of respiratory tract infections childhood and increases the risk of non-communicable diseases, including stroke, ischemic heart disease, chronic obstructive pulmonary disease, and lung cancer.

A meta-analysis of 41 studies showed that children living in homes with gas stoves had a 32% increased risk of developing asthma attacks. Indoor pollution can be a risk factor for future generations, potentially inducing adverse health effects even before birth, including impacts on neurodevelopment, cognitive function and behavioral disorders.

Practical solutions to reduce the risks of indoor air pollution

To effectively mitigate the risks of indoor air pollution, the study recommends several practical solutions that individuals can implement in their homes and other indoor environments:

a correct one ventilation management is crucial, with experts suggesting the Regular opening of windows to create cross ventilation, especially during and after cooking or cleaning activities. Installation and maintenance of extractor fans in kitchens and bathrooms can significantly reduce humidity and pollutant levels. For the warm-up , kitchen, the study highlights the importance of switching from gas stoves to electric alternatives, which can reduce the concentration of environmental nitrogen dioxide by up to 51%;
the regular one maintenance of air conditioning systems and smart filters ventilation is essential to prevent microbial growth and ensure optimal air quality. Experts also recommend minimize the use of chemicals such as synthetic air fresheners, harsh detergents and aerosols that can release volatile organic compounds;
choose building materials and furniture low-emissions, especially those without formaldehyde and others harmful substances, can further reduce exposure to hazardous chemicals;
to maintain indoor plants can help improve air quality by absorbing certain pollutants, although this should supplement rather than replace proper ventilation practices.

Implementing these simple measures, combined with increased awareness of the sources of indoor pollution, can significantly contribute to creating healthier indoor environments for children and families.

Indoor plants specifically for air purification

Although the original study does not refer to specific varieties of indoor plants for air purification, other scientific research has evaluated the effectiveness of some species. Taking into account that their effectiveness in real environments is much more limited than previously believed.

According to several scientific studies, plants such as sansevieria (mother-in-law's tongue), the pothos, the dracaena, the Spathiphyllum (peace lily), the fig benjamin, and the chlorophytum (spider plant) have shown the ability to reduce some volatile organic compounds (VOCs) under controlled conditions.

To have a significant impact on indoor air quality, impractical quantities of plants (10-100 plants per square meter) would be needed. The value of indoor plants remains considerable for other benefits, such as increased humidity, positive psychological effects and aesthetic benefits, which can indirectly contribute to overall well-being.

Prevention and risk reduction strategies

Experts also identified ten key actions that should be strengthened at national and local levels:

To publish updates regional and national periodicals of indoor pollution levels using appropriate indicators;
To integrate local health networks to develop science-based models and approaches for indoor air research;
Create one permanent national task force for epidemiological surveillance and risk analysis;
To organize training experiences based on local needs, with input from civic organizations;
To plan Preventive and corrective interventions, including the redevelopment of unhealthy buildings and polluted areas;
To provide sentinel doctors that can provide regular and standardized information using appropriate indicators;
To include training on the environment and pollution during medical degree courses and other health and non-health faculties;
Promote the medical awareness and knowledge of the environmental, social and cultural determinants of health;
Encourage the epidemiological and clinical research on the age- and gender-specific effects of indoor pollution;
Educate the population through family doctors, pediatricians and other professionals such as pharmacists and construction workers.

Conclusions and implications

The consensus of experts has highlighted theurgent need for an approach to indoor air and the environment from a health risk assessment and management perspectiveThe authors urged policy makers and health care providers to develop strategies to reduce indoor pollution through medical education, epidemiological studies, and public awareness campaigns.

These actions are consistent with the United Nations 2030 Agenda for sustainable development and addressing health inequalities. A global health strategy and a transdisciplinary approach One Health are recommended for the integrated protection of all living beings and the environment.

The study emphasizes that concrete indications and anticipatory guides, including scientific reports and awareness campaigns, should be targeted at the general population, with initiatives tailored for children to create a cascade of positive public health effects.

Dario Dongo

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