Several Chicago Public Schools (CPS) have reported mold growth issues this year, which authorities link to a combination of aging infrastructure and increasingly frequent heavy rainfall and humidity. School officials and experts warn that worsening climate patterns could further aggravate indoor environmental conditions, potentially affecting students’ and staff’s health.

CPS spokespersons emphasized the district’s commitment to maintaining safe, clean learning environments. They noted that routine environmental inspections are conducted regularly and that any mold found is addressed promptly. Despite these efforts, mold problems have surfaced at multiple schools, including Horace Greeley Elementary, Dr. Jorge Prieto Math and Science Academy, Irma C. Ruiz Elementary, Esmond Elementary, Northside Learning Center, William Howard Taft High School, and Kinzie Elementary, among others.

The Chicago Teachers Union (CTU) has called for increased state funding and disaster relief to help address these challenges. CTU Vice President Jackson Potter highlighted that CPS currently receives only 70% of the funding recommended by the state’s evidence-based formula and warned that without greater investment, mold outbreaks similar to those recently seen at Kinzie Elementary—which recorded indoor humidity levels exceeding 65%, well above the advised 30%-50% range—are likely to continue. The union pointed to these environmental hazards as a risk factor for respiratory illnesses among students.

Scientific research underscores the connection between changing climate conditions and mold proliferation. Illinois has experienced a 15% increase in rainfall since 1895, with data from the U.S. Global Change Research Program indicating that the most intense rainfall events in the Midwest have become 42% wetter between 1958 and 2016. Experts project these extreme precipitation events could increase by approximately 40% in the Midwest and Northeast by the end of the century.

Mold remediation expert Barton Robertson described 2026 as particularly difficult for moisture management, citing extended heat waves, elevated outdoor humidity, and heavy rains that add stress to older buildings. Common molds detected in affected CPS facilities include penicillium, aspergillus, Stachybotrys (commonly known as black mold), and Chaetomium. According to toxicology studies, some of these fungi produce compounds harmful to human health, especially in immunocompromised individuals.

Erica Washington, an assistant research professor at Duke University specializing in fungal biology, explained that rising global temperatures may enable certain fungal species to better tolerate human body heat, posing emerging health concerns. Mold growth, particularly on cellulose-based materials such as drywall, carpets, and furniture, can develop rapidly after water intrusion events following storms.

Mold exposure has been linked to aggravated asthma symptoms and hypersensitivity pneumonitis, a reversible lung disease characterized by coughing and wheezing if caught early. The disease’s incidence can depend on both genetic and environmental factors.

CPS’s current capital budget totals approximately $600 million, with $80 million allocated specifically for emergency repairs. Nevertheless, the district’s overall capital needs exceed $16.3 billion. A spokesperson from the Illinois governor’s office acknowledged a $2.5 billion funding increase for public schools since 2019 but cautioned against using one-time funds, such as the rainy day fund, for recurring expenses, advocating instead for responsible and sustainable financing strategies moving forward.