Scientists in America have identified the three types of mould that carry a direct link to the development of childhood asthma. Up until now the potential environmental causes of asthma have not been clearly understood, and whilst it was understood that the spores produced from mould could be linked to asthma, the individual forms of mould most responsible were not known. However in a long term population study of over 300 infants, researchers from the University of Cincinnati lead by Dr Tiinna Reponen have identified the three forms of mould that directly link to the development childhood asthma. The three forms of mould identified by the study are Aspergillus ochraceus, Aspergillus unguis and penicillum variable. All these three forms of mould are typically found growing in water damaged homes suffering from damp and other associated problems. The research is both significant and important as studies in America have found that 1 in 10 children have asthma and 1 in 20 adults also suffer from asthma. The research published in the August 2012 issue of the Journal of Allergy and Clinical Immunology assessed allergy development and the respiratory health of children annually for the first four years of life and then again at the age seven. The team monitored home allergens and mould and among the multiple indoor containment's assessed, only mould exposure during infancy emerged as a risk factor for asthma at age seven. Previous studies have linked mould to the development of childhood asthma, however, thanks to a new DNA based mould level analysis tool the researchers were able to combine analysis results of 36 different types of mould, and determine that these three types of mould and the concentration of them found in the study posed the greatest risk of asthma development during childhood. These findings are important as it will enable local authorities to more effectively run risk analysis on homes affected by damp, and thus deliver targeted action at the worst affected homes and the homes where people most vulnerable live.