Indoor wood burners linked to a decline in lung function
European Respiratory Society
image:
Dr Laura Horsfall
view moreCredit: Laura Horsfall/ERS
Using a wood burning stove at home can lead to a decline in lung function, according to research presented at the European Respiratory Society Congress in Amsterdam, the Netherlands [1].
The study was presented by Dr Laura Horsfall, Principal Research Fellow from the Institute of Health Informatics, University College London, UK.
The use of solid fuel for domestic heating has increased in Europe due to the marketing of wood as renewable energy and high fossil fuel prices. In the UK, the proportion of harmful PM2.5 air pollution (fine particulate matter) caused by domestic solid fuel is now 20% of the total, compared with 4% for road vehicle exhaust emissions. Annual emissions, specifically from domestic wood burning, almost doubled from 3,200 tonnes in 2009 to 6,000 tonnes in 2023.
Dr Horsfall told the Congress: “We know wood burning at home emits harmful air pollution both indoors and outdoors including known carcinogens. Despite this, air pollution from this source has approximately doubled in the UK since 2009 as more people install and use wood stoves. However, the link with health outcomes in high-income countries is not well understood and residential areas with high emissions are hard to identify using existing air quality monitoring networks.
Building on a previous study that mapped the use of solid fuel burning stoves across the UK, the researchers used data from the English Longitudinal Study of Aging (ELSA) [2] to study the connection between self-reported solid fuel use at home in England and lung function decline.
They assessed patients’ lung function according to a measure called FEV1, which quantifies the amount of air a person can forcefully exhale in the first second of a breath. Lower FEV₁ values are associated with increased risk of respiratory complications and poorer health outcomes, making FEV₁ a key objective marker in monitoring diseases like COPD and asthma.
Studying health impacts is challenging because wood-burning households tend to be wealthier and healthier overall. Dr Horsfall explained: “We found that people using solid fuel had lower rates of smoking and lung disease, which can mask the true effects of solid fuel exposure.
“However, using repeated lung function measurements over an eight-year period, we found that lung function declined faster among solid fuel users compared to non-users, even after adjusting for socioeconomic and housing factors. This suggests an important link between solid fuel use and respiratory decline, despite the healthier baseline of the exposed group.
“Our study suggests that high levels of particulate matter from stoves damage respiratory tissues, causing inflammation in a similar way to cigarette smoke,” she added.
Dr Horsfall and her team now plan to investigate whether people living in or near areas with a high concentration of wood stoves, such as the wealthier parts of London, also show increased rates of respiratory issues, such as inhaler prescriptions and hospital visits for lung conditions.
Professor Ane Johannessen, Head of the European Respiratory Society’s expert group on epidemiology and environment, based at the University of Bergen, Norway, who was not involved in the research said: "In Europe, we are seeing a growing trend for using wood-burning stoves at home. Research in other parts of the world, where traditional wood burning is used in the home, has shown that this is harmful and causes asthma, COPD and lung cancer.
"These findings suggest that wood-burners used in European homes may have similar effects and should be considered a potential environmental risk factor when assessing respiratory health, especially in patients with unexplained lung function decline or chronic respiratory symptoms. Although new eco-design European wood-burners are generally considered cleaner and safer than more traditional wood stoves, many European homes still employ older wood-burners, and even the newer stoves may not be entirely risk-free.
“This study underscores the need for clearer public health guidance and regulation around domestic wood burning. People should be aware that these stoves could be harming them and their families, and doctors should be asking their patients about whether they are using stoves at home.”
Method of Research
Observational study
Subject of Research
People
Estimated prevalence and concentration of wood fuel heat sources by Lower Super Output Area (LSOA), England and Wales. A. Top: Estimated prevalence of wood burners by LSOA, England and Wales. Bottom: Estimated prevalence of wood burners by LSOA, London. Local authorities of Richmond upon Thames, Kingston upon Thames, and Bromley highlighted in blue. B. Top: Estimated concentration of wood burners per km2 by LSOA, England and Wales. Bottom: Estimated concentration of wood burners per km2 by LSOA, London.
Credit
Laura Horsfall/ERS
Children lose 8.45 million days of healthy life due to second hand smoke
Children from low socio-economic regions face the biggest impact
CIGARETTE DUMPING BY BIG TOBACCO
image:
Dr Siyu Dai
view moreCredit: Siyu Dai/ERS
Children lose 8.45 million days of healthy life each year globally due to second hand smoke, according to research presented at the European Respiratory Society Congress in Amsterdam, the Netherlands [1]. Children from low socio-economic regions face the biggest impact of breathing second hand smoke, also known as passive smoking.
The study was presented by Dr Siyu Dai, Assistant Professor in the School of Clinical Medicine at Hangzhou Normal University and an Honorary Research Associate in the Department of Paediatrics at The Chinese University of Hong Kong.
She told the Congress: “Second-hand smoke is a major contributor to preventable illness and death in children and there is no safe exposure level. It is linked to chest infections, cardiovascular disease, and neurodevelopmental problems and makes asthma symptoms worse. Young children are especially susceptible because their bodies and lungs are still developing and they have little control over their own environments.
“Data from the World Health Organization estimate that second-hand smoke exposure causes 1.2 million premature deaths annually, including approximately 65,000 among children under the age of 15. But we know that many more children will suffer illness caused by other people smoking around them, so we wanted to quantify this problem globally and regionally, to provide evidence for more precise tobacco control policies.”
In the first global study to examine the impact of second-hand smoke (SHS) on children under 14 years old, Dr Dai and her colleague Miss Ruiying Jin analysed data from the Global Burden of Disease Study [2], a large international project that tracks deaths and illness from major diseases, injuries, and risk factors across the world.
One of its key measures is the disability-adjusted life year (DALY), which represents the total burden of disease. In simple terms, one DALY equals one year of healthy life lost (whether from dying too early or living with illness or disability).
Looking at data across more than 200 countries and territories, Dr Dai estimated the years lost to second-hand smoke across major disease categories from 1990 to 2021 in children aged 0–14 years. She then compared this to the Socio-demographic Index, which combines information on the economy, education, and fertility rate of countries around the world, as a representation of social and economic development.
She found that in 2021, SHS exposure contributed to 3.79 million DALYs from lower respiratory infections (acute bronchitis, pneumonia), 0.80 million from ear infections, and 3.86 million from chest infections and tuberculosis globally among children.
The researchers found that SHS continues to pose a serious health risk to children worldwide, but is particularly problematic in poorer regions, where the rates of disease burden (measured in DALYs) were much higher.
Regions that score highly on the Socio-demographic Index (SDI) reported age-standardised DALY rates of 7.64 and 10.25 per 100,000 children for lower respiratory infections and respiratory infections/tuberculosis, respectively, compared to low-SDI regions which showed rates of 302.43 and 305.40.
Dr Dai explained: “The impact of second-hand smoke on children’s respiratory health remains severe, but in some parts of the world, children are suffering even more than in others. Children in lower-SDI regions bear a disproportionate share of this preventable health burden. This likely reflects a combination of factors such as lower public awareness about the dangers of second-hand smoke, more overcrowded and poorly ventilated homes, and weaker tobacco control policies. These conditions may lead to higher exposure for children.
“In 2021 alone, exposure to second-hand smoke was linked to nearly 8.45m years of healthy life lost due to respiratory infections and tuberculosis, highlighting a preventable burden that falls most heavily on the least developed areas. Children are losing all these years of healthy life, but this could be prevented if they were protected from other people's smoke,” she added.
Dr Dai plans to carry out further analyses of SHS-related respiratory disease burden based on age, gender, and other factors, to support more precise and targeted interventions in the near future.
Dr Filippos Filippidis, Chair of the European Respiratory Society’s tobacco control committee, based at Imperial College, London, UK, who was not involved in the research said: "Around the world, hundreds of millions of people are still smoking and many are being exposed to second-hand smoke. Sadly, children often suffer the most as their lungs are still developing and they cannot avoid smoking in the home.
"This study quantifies the enormous harm children are suffering from second-hand smoke around the world. It is a wake-up call that we need to do much more to protect children. In particular, we need to create and enforce laws that limit smoking in places where children live or go to school. However, the most efficient approach is to reduce smoking across all age groups, which would substantially limit second-hand smoke exposure for children as well.
"As tobacco companies intensify marketing of emerging products, such as e-cigarettes and heated tobacco, it is also important to explore how these may indirectly affect children's health when they are exposed to second-hand vapours."
Method of Research
Observational study
Subject of Research
People
Map showing the global distribution of DALYs attributable to SHS among children under 14 years of age, across four major disease categories
Credit
Siyu Dai/ERS
