World Health Organization publishes its first indoor air quality guidelines on dampness and mold

World Health Organization publishes its first indoor air quality guidelines on dampness and mold

WHO guidelines for indoor air quality: dampness and mold

Copenhagen and Bonn, 16 July 2009

Today, WHO publishes its first guidelines on indoor air quality, addressing dampness and mould. (1) They are the result of a rigorous two-year review of the currently available science by 36 leading experts worldwide, coordinated by the WHO Regional Office for Europe. The authors conclude that occupants of damp or mouldy buildings, both private and public, have up to a 75% greater risk of respiratory symptoms and asthma. The guidelines recommend the prevention or remediation of dampness- and mould-related problems to significantly reduce harm to health.

“As people spend most of their daily lives in homes, offices, schools, health care facilities or other buildings, the quality of the air they breathe indoors is critical for their health and well-being,” says Dr Srdan Matic, Unit Head, Noncommunicable Diseases and Environment at the WHO Regional Office for Europe. “For the first time, these guidelines offer guidance to public health and other authorities on how to ensure safety and healthy conditions in buildings. We believe that this work will contribute to improving the health of people around the world.”

The book is the first in a series of WHO guidelines on indoor air quality. They are intended for worldwide use, to protect health under various environmental, social and economic conditions. Future publications addressing selected chemicals and combustion products are being prepared. Together, the guidelines will comprise the first-ever comprehensive evidence-based recommendations to tackle indoor air pollution, one of the major causes of death and disease worldwide.

Globally, about 1.5 million deaths each year, mostly among women and children in developing countries, are associated with the indoor combustion of solid fuels. In the European Union (EU) alone, combustion, chemicals from building materials and dampness cause an annual loss of over 2 million years of healthy life due to premature death or to chronic diseases, such as asthma and cardiovascular diseases.

In many EU countries, 20–30% of households have problems with dampness. Strong evidence indicates that this is a risk to health. In damp conditions, hundreds of species of bacteria and fungi grow indoors and emit spores, cell fragments and chemicals into the air. Exposure to these contaminants is associated with the incidence or worsening of respiratory symptoms, allergies, asthma and immunological reactions. Children are particularly susceptible. According to recent evidence, 13% of childhood asthma in developed countries in the WHO European Region could be attributable to damp housing.

Knowledge of indoor air pollutants is the key to enabling action to prevent related health effects and maintain clean air. Many of these actions are beyond the power of individual building users and occupants, and must be taken by public authorities. The guidelines recommend measures to ensure that buildings are well designed, constructed and maintained, and to make adequate housing and occupancy policies. Building owners are responsible for providing healthy workplaces or living environments, free of moisture and mould, by ensuring adequate insulation. Occupants are responsible for managing the use of water, heating and ventilation to avoid excess humidity.

“In the absence of clear evidence, building standards and regulations have not sufficiently targeted prevention and control of excess moisture. The new guidelines are essential, as they provide reference criteria for what constitutes healthy indoor air,” concludes Dr Michal Krzyzanowski, Regional Adviser, Noncommunicable Diseases and Environment at the WHO Regional Office for Europe, and the leader of the WHO project to draw up the guidelines. “More than 100 studies on the health effects of damp environments were reviewed in the preparation process. This body of evidence forms the basis of the guidelines and provides a solid foundation for action.”