After Hurricane Milton made landfall as a Category 3 storm in western Florida last week, residents who had evacuated are now returning to find water damage in their homes. Additionally, they may soon encounter mold growth.
Mold can start developing within 24 to 48 hours after exposure to moisture, and Florida’s subtropical climate—hot and humid in October—provides an ideal environment for its proliferation. Mold will continue to thrive as long as the source of moisture is present.
With climate change contributing to heavier rainfall and more intense storms, mold is expected to become a more prevalent issue. Warmer temperatures add moisture to the atmosphere, increasing the likelihood of severe precipitation events. Mary Johnson, a principal research scientist in environmental health at Harvard University, notes that mold is intrinsically linked to climate change. Extreme weather patterns, including hurricanes, enable water intrusion into homes and other indoor spaces, creating damp environments conducive to mold growth.
Instances of mold growth have been documented following major storms that resulted in flooding and water damage in residential areas. After Hurricane Katrina struck New Orleans in 2005, researchers from the US Centers for Disease Control and Prevention surveyed 112 flooded homes and discovered visible mold growth in nearly half of them. Johnson’s research has also found a connection between higher temperatures, increased precipitation, and elevated mold spore levels in the outdoor air.
Mold, a type of fungi, naturally occurs in the environment and has existed on Earth for millions of years. In outdoor settings, it plays a vital role in 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 functioning like seeds, disseminate through the air both outdoors and indoors. When inhaled, these spores have the potential to cause respiratory symptoms, itchy eyes, infections, or skin rashes. They can also trigger severe asthma attacks, though not everyone is affected by mold exposure.
Ronald Saff, an internal medicine doctor, allergist, and immunologist based in Tallahassee, Florida, explains that people are generally able to handle mold exposure. “People are exposed to molds at fairly high concentrations when they go for a walk in the park or in wooded areas,” Saff states.
