Following Hurricane Milton’s impact as a Category 3 storm in western Florida last week, many residents who had evacuated are now returning to find water damage in their homes. They may soon face an additional concern: mold.
Mold can start to develop within 24 to 48 hours after moisture exposure, and Florida’s subtropical climate, which remains hot and humid in October, provides ideal conditions for its growth. Mold will persist in growing until the moisture source is removed.
With climate change promoting heavier rainfall and more severe storms, mold is likely to become a more frequent issue. Warmer temperatures increase atmospheric moisture, leading to more intense precipitation events. According to Mary Johnson, principal research scientist of environmental health at Harvard University, “Mold is absolutely associated with climate change.” Extreme weather patterns, including hurricanes, can result in water intrusion in homes or other indoor spaces, which, when damp, increases the likelihood of mold growth indoors.
Instances of mold growth have previously been recorded following significant storms that led to flooding and water damage in residential areas. For instance, several months after Hurricane Katrina struck New Orleans in 2005, researchers from the US Centers for Disease Control and Prevention examined 112 homes affected by flooding and discovered that nearly half exhibited visible mold growth. Johnson’s research has also associated higher temperatures and increased precipitation with more mold spores in outdoor air.
Mold, a type of fungi, is a natural part of the environment and has existed for millions of years. It plays a crucial role outside by decomposing organic materials like dead trees and leaves. However, indoors, mold can pose health risks, particularly to children, individuals with allergies and asthma, and those with weakened immune systems.
Mold spores, which are reproductive cells that act like seeds, travel through the air both outdoors and indoors. Inhaling these spores can lead to respiratory symptoms, itchy eyes, infections, or skin rashes, and can trigger serious asthma attacks. Nonetheless, not everyone is affected by mold exposure.
“Our bodies, for the most part, deal with mold,” says Ronald Saff, an internal medicine doctor, allergist, and immunologist based in Tallahassee, Florida. “People are exposed to molds at fairly high concentrations if they go for a walk in the park or in wooded areas.”