Experts: Wildfire smoke causes immediate and long-term respiratory and systemic risks; lithium-ion battery fires may add metals exposure

The California State Assembly Health Committee heard testimony that wildfire smoke can cause immediate respiratory crises and long-term systemic health effects, and that fires involving electric vehicles and battery storage may add toxic metals to the smoke.

Dr. John Belperio, chief of the Division of Pulmonary, Critical Care, Allergy, Immunology and Sleep at the University of California, Los Angeles, told the committee that particulate matter from wildfires—particularly PM2.5—penetrates deep into the lung, causes compartmental lung inflammation and can trigger exacerbations of asthma, chronic obstructive pulmonary disease (COPD), interstitial lung disease and rejection in lung-transplant patients. "When that ... PM2.5 gets into the lung, it's very hard for the lung to remove it," Belperio said, adding that systemic inflammation from particulate inhalation can affect the brain, carotid arteries and heart, and may contribute to preterm labor in pregnant people.

Why the issue matters: Committee members were told the physical harms include increased emergency-room visits, hospitalizations and deaths for vulnerable patients; experts cautioned the health system will also face longer-term disease burden from repeated exposures.

Key findings and context - Belperio described particulate matter sizes and biology, noting that PM2.5 reaches the deepest lung compartments and provokes white blood–cell–mediated inflammation that can become systemic. He said wildfire smoke led to clinical decompensation in lung-transplant and severe interstitial-lung-disease patients and increases infections by impairing immune function. - In response to questions, Belperio said lithium-ion batteries in vehicles and energy storage that burn at high temperatures can release additional metals (he listed lead, manganese, tungsten carbide and beryllium as examples) and other combustion products. He warned these metal-rich emissions can increase airway injury and, in some cases, produce granulomatous lung disease resembling sarcoidosis. "We do have to watch for that," he said. - Committee discussion noted limits of current monitoring: Belperio and others said typical air-quality indexes correlate with many hazardous compounds but do not measure every chemical (for example asbestos or specific metals) and urged physicians to evaluate symptomatic people (chest X-ray, pulmonary-function tests) rather than attributing all breathing problems solely to smoke.

Local advice and clinical implications Public-health and clinical speakers urged precaution: when visible smoke is present, people should stay indoors, seal leaks, avoid outdoor exercise and use N95 respirators for short trips outside. For post-fire cleanup and sites with ash or debris, speakers emphasized specialized cleanup protocols and that people with symptoms seek medical evaluation. Belperio said N95s are effective for many smoke particulates but that P100 filters are needed to protect against asbestos and some demolition dusts.

Outstanding uncertainties and next steps Experts asked for expanded monitoring and targeted research on the health consequences of battery fires, and for clinicians to track patients who had heavy exposures. Committee members and witnesses emphasized that early clinical evaluation can detect treatable infections and complications that might otherwise be attributed to smoke alone.

Ending: The panel’s testimony linked immediate clinical guidance (stay indoors, use appropriate masks, seek care for new or worsening respiratory symptoms) to a larger research need: more environmental monitoring of metals and chemical byproducts from modern structure and vehicle fires and longitudinal study of affected patients.