1. No category

Health effects of
damp and mould
Jenny Griffiths
Health effects of damp and mould
• Dampness and mould do have serious potential
health impacts …
• But not inevitably so – many people escape
unscathed
• Though always the impact on well-being from
discomfort, visual mess
• Cold and damp can go together – fuel poverty
(when people spend more than 10% of income on
heating)
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Main source – review of evidence
• World Health Organisation Europe 2009
• Guidelines for Indoor Air Quality, Dampness and
Mould
• Supported by UK Department of Health
• Comprehensive review of the scientific evidence
• Multi-disciplinary group of experts from across
Europe
Dampness = excess moisture
• European studies suggest that about 20% of
buildings have some sign of dampness
– Water leakage or damage, discoloration
– Visible mould growth on walls, floors or ceilings
• Some UK studies report up to 50% of houses showing
some signs of damp and 25% having mould
• Highest in deprived neighbourhoods
• Also office buildings, schools etc.
• Climate change is increasing the problem because of
more extreme weather events, e.g. flooding
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HOW does dampness cause health
damage?
• Leads to growth of microbes, such as mould,
fungi and bacteria
• Emit spores, cells, fragments and volatile
organic compounds into the air
• Dust mites and fungi especially – flourish in
damp and are associated with allergies and
asthma
• Dampness also initiates chemical or
biological degradation of materials, e.g.
furnishings, causing indoor air pollution
Who is at risk?
• People sensitive to allergens are particularly
susceptible – but can affect others too
• Some people more sensitive
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Babies and children
Elderly people
Those with allergic skin problems, e.g. eczema
Those with respiratory problems, e.g. asthma, COPD
Those with a weakened immune system
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Key health impacts from studies
• In houses with visible dampness, mould or
mould odour, for both adults and children:
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52% increase in upper respiratory tract symptoms generally
50% increase in cough; 44% increase in wheeze
50% increase in symptoms of current asthma
30% increase in those who develop new asthma,
especially children who may be genetically susceptible
to asthma development
– USA study suggested 20% of cases of asthma there could
be attributed to residential dampness and mould
Other health effects of mould etc.
• Fungal infections – in open wounds, and feet, skin, hair
and nails
• Some (but less) evidence that exposure increases the
risks of rare conditions
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Hypersensitivity pneumonitis
Allergic alveolitis
Chronic rhinosinusitis
Allergic fundal sinusitis
• Can also affect the immune system
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Summary
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Damp and mould do have serious health impacts
In 20 – 50% of houses, also some schools, offices
People have allergic reactions to spores, bacteria etc.
Main impacts are a worsening of respiratory problems,
including asthma, affecting up to 50% of those living in
damp and mouldy conditions
• Especially in vulnerable groups, including children
• May directly cause asthma
• Also skin allergies and fungal infections
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