Winter vacation, indoor air pollution and respiratory health among rural college students: A case study in Gansu Province, China

Indoor air pollution (IAP) is one of the most important risk factors contributing to respiratory health. This study aims to assess the respiratory effects of IAP caused by coal stoves and Chinese kang among rural college students during the winter vacation in Gansu Province, China. Seventy rural college students took the questionnaire survey, urine collection and spirometry tests before, during and after their winter vacations. IAP levels were evaluated by IAP exposure index. Linear mixed effect model and generalized linear mixed models were used to estimate the effect of IAP exposure index presented on respiratory health. Comparing with before and after the winter vacation, we found that there were the greater incidences of respiratory symptoms (chi(2) = 19.54; p < 0.05) and the higher levels of urinary 8-epi-prostaglandin F2 alpha (8-epi-PGF2 alpha), and the FEV1/FVC ratio decreased significantly during the winter vacation(p < 0.05). Every 1 unit increase in IAP exposure index was associated with an increase of 10.11% (95%CI: 0.97%-20.08%) 8-epi-PGF2a after adjusting for other variables (p < 0.05); and the risk of respiratory symptoms increases by 42% (OR: 1.42; 95%CI: 1.09-1.84) for every 1 increase in IAP exposure index. Our results indicate that, even during a short vacation period, the IAP caused by the use of coal stoves and Chinese kang in rural areas is associated with adverse respiratory health effects among healthy young adults, highlighting the importance of mitigating pollution from Chinese kang and coal stove.