Chronic Rhinosinusitis / Sinusitis (Airborne Hazard) Secondary to Burn Pit / Airborne Hazard Exposure (PACT Act)

Yes. Under 38 CFR § 3.310(a), any disability proximately caused or chronically worsened by a service-connected condition is itself service-connected. Chronic Rhinosinusitis / Sinusitis (Airborne Hazard) is a documented secondary pairing for Burn Pit / Airborne Hazard Exposure (PACT Act) with moderate medical evidence. A nexus letter from a qualified physician linking the two conditions is the most reliable way to establish this connection.

The gold standard is a private nexus opinion stating — to at least a 50% probability ("at least as likely as not") — that the secondary condition was caused or aggravated by the primary service-connected condition. Peer-reviewed medical literature supporting the physiological mechanism strengthens the nexus. Treatment records documenting the onset or worsening of the secondary condition in temporal relation to the primary are supporting evidence.

The VA rates Chronic Rhinosinusitis / Sinusitis (Airborne Hazard) separately under its own 38 CFR Part 4 diagnostic code, then combines it with Burn Pit / Airborne Hazard Exposure (PACT Act) and all other service-connected ratings using the combined ratings formula under § 4.25. The formula applies the whole-person concept: a 50% combined existing rating plus a new 30% rating yields 65% (rounded to 70%), not 80%.

38 CFR § 3.310(a) states: "Disability which is proximately due to or the result of a service-connected disease or injury shall be service connected." The aggravation variant under § 3.310(b) applies where the primary condition permanently worsens a pre-existing disability beyond its natural progression. Both standards require a showing of nexus — a medical or scientific link between the primary condition and the secondary.

The medical evidence supporting Chronic Rhinosinusitis / Sinusitis (Airborne Hazard) as secondary to Burn Pit / Airborne Hazard Exposure (PACT Act) is rated moderate. Burn pit combustion products — a complex mixture of fine particulate matter (PM2.5), volatile organic compounds (benzene, toluene), dioxins, polyaromatic hydrocarbons, and heavy metals — produce chronic upper respiratory inflammation through direct mucosal toxicity and immune sensitization. Inhaled particles deposit in the nasal and sinus mucosa, triggering persistent innate immune activation, mucociliary clearance dysfunction, and biofilm formation by opportunistic bacteria in the inflamed mucosa. Sinus ostial inflammation causes obstruction of mucociliary drainage, creating the anatomical conditions for chronic sinusitis: blocked drainage, bacterial/fungal colonization, and persistent mucosal edema. Clinical studies of OEF/OIF veterans with documented burn pit exposure document chronic rhinosinusitis rates 2–3 times higher than non-deployed veteran controls. The PACT Act (2022) expanded presumptive service connection for many airborne hazard conditions.

The VA will not solicit nexus evidence on your behalf for secondary claims. In practice, a written nexus opinion from a private physician or independent medical examiner is essential — the VA's Compensation & Pension (C&P) examiner is not required to produce a favorable nexus opinion, and the VA has discretion to weigh competing opinions. Submitting a private nexus letter at the time of filing is the most reliable strategy.