Secondhand Smoke Exposure Across Five Campus Settings and Its Association with Smoke-Free Policy Implementation Among Chinese College Students - China, 2025.

What is already known about this topic?: Secondhand smoke (SHS) exposure remains a significant public health concern among college students, even where smoke-free campus policies are in place. What is added by this report?: This report documented SHS exposure across five campus settings among Chinese college students in 2025, revealing substantial variation in prevalence by setting. School-level factors - particularly the comprehensiveness of smoke-free policies and teachers' smoking behavior on campus - were more strongly associated with student exposure than the broader tobacco-control environment. What are the implications for public health practice?: Colleges should strengthen comprehensive smoke-free policy implementation, as has been achieved in primary and secondary schools, to reduce student SHS exposure.