New Way to Determine Moldiness of Homes

As part of the Inner-City Asthma Study, George T. O'Connor, MD, MS, Boston University School of Medicine, and colleagues measured the concentrations of airborne fungi inside and outside the homes of 414 mold-sensitive children with moderate to severe asthma in seven low-income urban communities across the United States. Researchers analyzed the relation of the concentration of fungi in indoor air to home characteristics and to the outdoor concentration on the day of the measurement. The research was done as part of the Inner-City Asthma Study.

Previous studies have shown that the most common types of airborne fungi, Alternaria, Cladosporium, Penicillium, and Aspergillus, are present in outdoor air and in many indoor environments. The current study found that the levels of these fungi found indoors actually matched those found outdoors across all seven cities, suggesting that the outdoor concentration is an important determinant of the indoor concentration.

Researchers noted:

> Higher levels of fungi were significantly more likely to be found in homes with reported water damage, dampness, or leaks in the past 12 months. This supports the belief that fungi play a role in the association between home dampness and respiratory symptoms.

> Evidence of cockroach infestation in the child's bedroom was found in homes with higher levels.

> Higher levels of fungi were also found in homes containing cats. This may be the result of fungal growth in a damp litter box or the large amounts of organic material that cats add to house dust.

Researchers noted that a higher concentration of fungi was less likely in homes with forced air heating and in homes with higher bedroom temperatures.

Exposure to airborne fungi may lead to allergic sensitization and provoke allergy and asthma symptoms. This is the first study to report on the exposure to airborne fungi in asthmatic children living in U.S. inner cities, a group with high morbidity and frequent sensitization to mold. The results of the JACI study may provide a valuable metric for future epidemiologic investigations of the role of fungal exposure as a risk factor for disease.