Objective To investigate the cognition of PM_2.5 in medical and non-medical students of a medical college to provide reference for the training of students in medical institution.

Methods The survey was conducted by self-designed questionnaire in 150 medical and 50 non-medical students selected by random sampling. The reliability and validity of the questionnaire were analyzed by SPSS 18.0.

Results The questionnaire was good in internal consistency and construct validity with a Cronbach's α coefficient of 0.809, a cumulative contribution rate > 65%, a common value > 0.45 and a maximum factor loading > 0.60. The awareness rate of knowledge on PM_2.5 was 53.3%. The awareness rate on the artificial source of pollution was higher than that on natural source of pollution, and the awareness rate on the health lesion of respiratory system was higher than that of reproductive and cardiovascular system. The cognition on the effect of 5 items, such as "the smoke in kitchen" (AS8), "elevated blood lipids" (H3), "neonatal underweight" (H5), "PM_2.5 on respiratory mucosa" (Q2) and "forest planting" (P1), was significantly different between medical and non-medical students. The awareness rate of AS8, H3, H5 and Q2 in medical was higher than that in non-medical students. The awareness rate of P1 in non-medical students was higher than that in medical.

Conclusion Setting public elective courses on environment and health and developing voluntary activities are helpful for improving the cognition on environmental protection and developing health propagation and education.