C59-09 From Clean to Compromised: Microplastic Exposure and Ozone-based Continuous Positive Airway Pressure Cleaning Associated With Diffuse Alveolar Hemorrhage and Interstitial Lung Disease

Abstract Introduction Research on ozone (O3) and microplastics has grown rapidly, revealing harmful effects on lung epithelium despite O3’s proposed therapeutic use. As continuous positive airway pressure (CPAP) technology and ozone-based innovations expand, unintended consequences such as foam inhalation and ozone-related pulmonary toxicity are increasingly recognized. The Food and Drug Administration (FDA) recalled SoClean in 2023 after reports of ozone-related respiratory complications and Philips CPAP machines in 2021 due to polyester-based polyurethane (PE-PUR) foam inhalation, a microplastic derivative. Combined ozone and microplastic exposure from these devices has been linked to interstitial lung disease (ILD). We report a case of ILD likely secondary to ozone and microplastic exposure from SoClean use and CPAP foam inhalation. Case Report We present a 62-year-old man with obstructive sleep apnea (OSA) on CPAP, end-stage renal disease (ESRD) secondary to hypertensive nephropathy, status post kidney transplant in 2020 complicated by acute cellular rejection and requiring hemodialysis since 2023. He presented with progressive dyspnea on exertion and intermittent hemoptysis for six months. On admission, his oxygen saturation was 84% on room air, and chest imaging showed pulmonary edema and ground-glass opacities. Bronchoscopy with bronchoalveolar lavage (BAL) revealed diffuse alveolar hemorrhage (DAH) in multiple lobes. With corticosteroid therapy, his symptoms resolved, and he was discharged on a prednisone taper. At follow-up, pulmonary function tests demonstrated a restrictive pattern with reduced lung volumes and diffusion capacity. Autoimmune workup was unremarkable except for a positive antinuclear antibody (1:160). History revealed long-term use of a recalled Philips CPAP device and a SoClean CPAP cleaning device for three years. He was advised to discontinue both and obtained a new CPAP machine. Lung biopsy showed acute hemorrhage with hemosiderin-laden macrophages; BAL cytology was negative for malignancy. In the absence of infectious or autoimmune causes, prolonged exposure to ozone and microplastic particles was suspected to underlie his DAH and ILD. Discussion This case highlights pulmonary toxicity, including DAH and ILD, linked to ozone-based CPAP cleaners and microplastic exposure. Although ozone (O3) has therapeutic potential, its strong oxidative properties pose risks when misapplied. Devices intended to aid chronic illness management may inadvertently release harmful particles, as seen with recalled CPAP machines. Ozone can damage lung epithelium and oxidize device materials, generating microplastics that drive inflammation and fibrosis, while foam degradation in CPAP machines further microplastic exposure. Additional research is needed to clarify respiratory effects of ozone exposure and increase public awareness of these emerging environmental hazards. This abstract is funded by: None