Poor indoor air quality in low-income UK urban residences causes significant health impacts, including 3,000 lost DALYs annually from formaldehyde and mould exposure, with London alone facing economic costs of £1.4-3.7 billion per year.
Abstract
Poor indoor air quality in low‐income urban residences in the UK is linked to measurable health and economic costs. In England, exposure to formaldehyde is associated with roughly 800 disability‐adjusted life years (DALYs) lost annually among children aged 0–14, while damp and mould exposure accounts for about 2200 DALYs lost yearly in the 0–49 age group, with an additional 600 DALYs lost from lower respiratory infections. In London, various health impacts translate into annual costs estimated between £1.4 billion and £3.7 billion.
Studies also document that housing factors amplify these burdens. Smaller dwellings with limited ventilation and higher occupancy—as well as proximity to major roads—yield higher indoor concentrations of pollutants such as PM2.5 in low‐income areas. Modelling of energy efficiency retrofits indicates that such interventions can result in changes of–728 to +2241 quality‐adjusted life years (QALYs) per 10,000 persons over 50, depending on implementation. These findings, based on modelling, burden assessments and case studies, underscore the tangible health and economic impacts arising from poor indoor air quality in low‐income urban settings in the UK.
Paper search
Using our research question ”What are the economical and health-related hidden costs of poor IAQ (indoor air quality) in residential settings for low-income urban populations?”, we searched across over 126 million academic papers from the Semantic Scholar corpus. We retrieved the 50 papers most relevant to the query.
We screened in papers that met these criteria:
- Population: Does the study focus on low-income households in urban areas within the UK?
- Setting: Is the study conducted in residential buildings (flats, council houses, or private rentals)?
- IAQ Measurements: Does the study include quantitative measurements of indoor air pollutants?
- Outcomes: Does the study report either health outcomes (e.g., respiratory conditions, allergies, mental health) OR economic outcomes (e.g., healthcare costs, lost workdays, energy costs)?
- Study Design: Is the study design one of the following: systematic review, observational study, economic evaluation, or mixed-methods study with quantitative components?
- Indoor Air Focus: Does the study include indoor air quality measurements (not exclusively outdoor air)?
- Outcome Linkage: Does the study link building characteristics or IAQ measurements to health or economic outcomes (rather than just reporting measurements)?
- Population Scope: Does the study analyse data from multiple households (not just a single case study)?
We considered all screening questions together and made a holistic judgement about whether to screen in each paper.
Data extraction
We asked a large language model to extract each data column below from each paper. We gave the model
the extraction instructions shown below for each column.
Study Design:
Identify the specific type of study design used:
- Specify if it is a modelling study, simulation study, population-level framework, or burden of disease assessment
- Note any specific methodological approaches (e.g., EnergyPlus simulations, data pooling, epidemiological analysis)
- If multiple methods are used, list all in order of prominence
- If method is unclear, write ”Unable to determine from available text”
Geographic Setting and Population Characteristics:
Extract detailed information about:
- Specific geographic region (e.g., England, specific urban areas)
- Demographic characteristics of the population studied
- Income groups or socioeconomic strata examined
- Specific vulnerable populations mentioned (e.g., ethnic minorities, children, elderly)
- Use exact quotes or numerical data if available
- If information is partial, note which aspects are missing
Indoor Air Quality Parameters Measured:
List all specific indoor air quality parameters:
- Exact pollutants measured (e.g., PM2.5, formaldehyde, temperature)
- Measurement units
- Sources of pollutants (indoor vs outdoor)
- Concentration levels if reported
- Measurement methods used If multiple parameters, list in order of study focus
Health Outcomes Related to Indoor Air Quality:
Identify and extract:
- Specific health outcomes linked to indoor air quality
- Quantitative health impact metrics (e.g., new disease cases, Disability Adjusted Life Years)
- Specific population groups most affected
- Numerical data on health burden if available
- Use exact figures from the study
Economic and Social Inequalities:
Extract information about:
- Economic disparities related to indoor air quality
- Social inequalities in housing and environmental exposure
- Specific indicators of economic disadvantage
- Quantitative evidence of unequal exposure
- Policy implications mentioned
- Use direct quotes or numerical data where possible
Results
Characteristics of Included Studies
| Study | Study Type | Population Focus | Key Pollutants Studied | Primary Outcomes |
|---|---|---|---|---|
| Clark et al., 2023 | Burden of disease assessment | England, population aged 0-14 (~10 million) and 15-49 (~25 million) | Formaldehyde, damp, mould | New cases of asthma and lower respiratory infections, Disability-Adjusted Life Years (DALYs) lost |
| Cole et al., 2024 | Population-level framework using building simulations | England and Wales, focus on urban areas | Particulate matter with a diameter of 2.5 micrometres or less (PM2.5) from outdoor sources | Indoor PM2.5 concentrations, indoor temperatures |
The report identified 9 studies focusing on indoor air pollution in the UK, primarily in England. Key characteristics of these studies include:
- Study types: Predominantly modelling studies, with one burden of disease assessment and one case control study.
- Pollutants: PM2.5 was the most frequently studied pollutant (5/9 studies). Other common pollutants included VOCs, NO2, and mould.
- Geographic focus: Most studies (6/9) focused specifically on England, with others examining the UK more broadly or developed countries in general.
- Population focus: Studies covered various age groups and socioeconomic statuses, with some specifically targeting low-income or deprived communities.
This diversity in study types, pollutants, and populations provides a comprehensive overview of indoor air quality issues in the UK, particularly for low-income urban populations.
Quantitative Effects
Health-Related Economic Impacts
| Region | Key Areas | Why | |
|---|---|---|---|
| London Borougns | Haringey, Hammersmith & Fulham, Lambeth, Lewisham, Camden, Islington, Southwark | High-density housing, older property stock, and a large private rented sector (where 9% of homes have damp). Overcrowding and poor ventilation exacerbate condensation issues. | |
| North West England | Rochdale, Manchester, Oldham, West Lancashire, Blackburn, Gateshead | Aging housing stock, higher poverty rates, and colder climate. Rochdale gained national attention after the mould-related death of toddler Awaab Ishak | |
| Yorkshire & The Humber | Leeds, Sheffield, Kirklees, Bradford | High rates of non-decent homes (poor insulation, structural defects) and a large private rented sector. Kirklees Council faced regulatory action for backlogged damp repairs |
The report identified information on health conditions, associated costs, affected populations, and quality of evidence for 7 studies related to housing and health impacts in England. Key findings include:
- Health conditions: Studies focused on respiratory issues (asthma, lower respiratory infections) and various unspecified health impacts.
- Cost metrics:
- DALYs: Ranging from ~600 to ~2200 DALYs annually
- QALYs: Ranging from-728 to +2241 QALYs per 10,000 persons over 50 years
- Monetary costs: £1.4 billion to £3.7 billion annually in London
- Affected populations: Varied from specific age groups (e.g., children aged 0-14) to broader population segments (e.g., English household population).
- Quality of evidence: All studies were rated as having moderate quality of evidence.
These findings highlight the significant economic and health burden associated with poor indoor air quality, particularly for respiratory conditions. The variation in QALY outcomes across different scenarios under scores the complexity of interventions and their potential for both positive and negative impacts.