Mold and heat closed Pittsburgh-area schools – an expert explains the risks to kids
Many older school buildings lack air conditioning, leaving fans as the main defense against classroom heat. RJ Sangosti/MediaNews Group/The Denver Post via Getty Images For many southwestern Pennsylvania students, this school year has already included days away from the classroom because of the buildings themselves.
In southwestern Pennsylvania, multiple school districts canceled in-person classes at the start of the 2026-2027 school year due to environmental hazards. Mold forced delays or closures in at least four districts, including Monessen City School District, Laurel Highlands Middle School, Ligonier Valley School District, and Homer-Center School District. Meanwhile, extreme heat in early September prompted Pittsburgh Public Schools to switch to remote learning for 35 buildings, as their lack of adequate cooling systems made classrooms unsafe. These issues reflect a broader trend in Pennsylvania, where a 2025 statewide study found widespread environmental hazards like mold, lead, and radon in schools. The average age of Pennsylvania school buildings is 70 years, 20 years older than the national average, with Pittsburgh Public School buildings averaging 90 years old.
Older school buildings often contain hazards that newer constructions avoid, such as mold, lead, asbestos, and radon. Asbestos, a fibrous substance used historically for fire resistance, becomes dangerous when damaged, releasing fibers that can cause cancer. Central Valley School District in Beaver County is currently undergoing asbestos abatement in its middle- and high-school buildings, built in the 1960s, though students continue attending classes during the process. Lead, a naturally occurring metal, poses neurological risks when ingested, particularly for children whose bodies are still developing. It can enter schools through deteriorating paint or old plumbing, where water sitting in pipes absorbs lead. Radon, a colorless, odorless gas, seeps into buildings through cracks and can cause lung cancer. The Environmental Protection Agency estimates nearly 1 in 5 schools has at least one classroom with unsafe radon levels.
Mold is a type of fungus that thrives in damp indoor environments, releasing spores, allergens, and irritants that can harm health. Short-term exposure may cause sinus congestion, coughing, wheezing, eye irritation, or skin rashes. Long-term exposure can lead to chronic bronchitis, asthma, lung inflammation, headaches, memory loss, or fatigue. The Asthma and Allergy Foundation of America notes that mold can trigger severe asthma attacks in children with the condition. Damp, moldy spaces can increase the risk of breathing problems by up to 50%, according to the Environmental Protection Agency. Remediation requires immediate action, as mold spreads quickly and causes further damage to both health and property if left untreated. Schools must address the moisture source to prevent mold from returning.
Extreme heat poses significant risks to students, particularly in older buildings lacking proper cooling systems. During a September 2026 heat wave, Pittsburgh Public Schools switched to remote learning when classroom temperatures reached 90 degrees Fahrenheit or higher, as part of their extreme heat protocol. High indoor temperatures can cause discomfort and increase the risk of heat-related illnesses like heat exhaustion or heatstroke, which strain the heart and kidneys. Heat waves can also worsen chronic conditions and lead to acute kidney injuries. Beyond health risks, heat negatively impacts learning: a study of 10 million students who took the PSAT found that each 1-degree Fahrenheit increase in average school-year temperature reduced learning that year by about 1%.
Children are more vulnerable to environmental hazards than adults because their bodies are still developing. This principle, highlighted in Rachel Carson’s 1962 book *Silent Spring*, underscores that exposure to toxins can have greater long-term effects on children. For example, lead poisoning can cause learning disabilities and developmental delays, even at low levels. Mold spores and indoor dampness disproportionately affect children’s developing airways, increasing the risk of asthma and other respiratory issues. Pennsylvania schools are required by the *Asbestos Hazard Emergency Response Act* to inspect buildings for asbestos and create management plans to reduce exposure. Federal and state agencies offer grants and resources to help schools improve indoor environments, emphasizing the importance of healthy spaces for student learning and safety.
