Introduction

This report assesses the health and economic impacts of indoor nitrogen dioxide (NO₂) exposure from gas cooking across the European Union (EU) and the United Kingdom (UK), and evaluates the potential benefits of transitioning to cleaner cooking technologies.

Gas cooking as a source of indoor air pollution

Gas cooking appliances emit NO₂ directly into indoor environments. As cooking occurs close to occupants and often in inadequately ventilated spaces, exposures can be substantial compared with outdoor air pollution sources.

Indoor NO₂ levels associated with gas cooking

Households using gas cookers experience significantly higher indoor NO₂ concentrations than those using electric appliances. In several countries, estimated indoor levels exceed the 2021 WHO annual guideline of 10 μg/m³, even where ambient outdoor concentrations remain compliant.

Gas cooking use across Europe

Gas cooking remains widespread across Europe, particularly in Italy, Poland, Romania, France and the UK. Around 180 million people across the EU and UK are estimated to live in households using gas cooking appliances.

Health effects associated with gas cooking

Gas cooking has been associated with increased asthma prevalence, particularly among children. Evidence suggests stronger associations with the presence of gas cookers than with NO₂ exposure alone, indicating additional exposure pathways or unmeasured pollutants.

Health effects associated with NO₂ exposure

Long-term NO₂ exposure is linked to increased all-cause and respiratory mortality. Meta-analyses indicate a 2–3% increase in mortality risk per 10 μg/m³ increase in NO₂. Both short- and long-term exposure are also associated with asthma symptoms, hospital admissions and reduced lung function.

Economic costs associated with NO₂ exposure

Health impacts attributable to NO₂ exposure result in significant economic costs through premature mortality, years of life lost and asthma-related disability.

Objectives

The study aims to quantify mortality and asthma cases attributable to indoor NO₂ exposure and the presence of gas cookers, and to estimate the associated economic costs across the EU and UK.

Methodology

Health impact assessment (HIA)

A standard health impact assessment framework was applied, estimating population-attributable fractions for mortality and asthma linked to gas cooking and NO₂ exposure.

Concentration-response functions

Concentration–response functions were derived from peer-reviewed meta-analyses for mortality and asthma, assuming applicability to indoor exposure settings.

Estimation of indoor exposures to NO₂ according to cooking fuel per country

Indoor NO₂ concentrations were estimated using indoor-to-outdoor ratios from a multi-country measurement campaign combined with ambient NO₂ data from the European Environment Agency.

Description of population composition

Population distribution and gas cooker prevalence were sourced from Eurostat at national and regional levels.

Description of health outcome background rates

Baseline mortality and asthma prevalence rates were obtained from Eurostat, WHO and Global Burden of Disease databases.

Description of baseline and modelling scenarios

The baseline scenario reflects current gas cooking use, while the counterfactual assumes a full transition to clean cooking technologies.

Economic valuation

Economic impacts were valued using the Value of a Statistical Life and Value of a Statistical Life Year, adjusted for country-specific income and inflation.

Results and discussion

Estimation of indoor NO₂ exposures in homes that use gas cooking

Indoor NO₂ concentrations in gas-cooking homes are consistently higher than in homes using electric cooking and frequently exceed WHO guidelines.

Mortality

Approximately 36,000 premature deaths and 61,000 years of life lost are estimated annually in the EU due to gas cooking-related NO₂ exposure. Including the UK, this increases to around 40,000 deaths and 77,000 years of life lost, with total mortality costs estimated at €160 billion.

Asthma

An estimated 25,000 paediatric asthma cases in the EU (41,000 EU+UK) are attributable to NO₂ exposure. When considering the presence of gas cookers, total asthma cases exceed 1 million across all ages in the EU and UK, with associated costs exceeding €4 billion.

Strengths And limitations

Strengths include the first EU- and UK-wide spatial mapping of indoor NO₂ exposure and integrated health and economic valuation. Limitations include potential underestimation of indoor NO₂ levels, exclusion of other pollutants, and data gaps for certain health outcomes.

Conclusions

Gas cooking represents a significant public health and economic burden across Europe. Transitioning to cleaner cooking technologies could substantially reduce mortality, asthma prevalence and associated costs, supporting targeted policy intervention.