Temperature inversion and air pollution relationship, and its effects on human health in Hanoi City, Vietnam.

This study aimed to investigate the effects of temperature inversions on the concentration of some pollutants in the atmosphere in Hanoi City, Vietnam, during the period from 2011 to 2015. This work also aimed to evaluate relationships between the thermal inversion and health effects that are associated with air pollution. During this period, the temperature inversions were most frequently presenting from November to March in Hanoi City. Air quality data was gathered from air quality monitoring stations located in the study area. The data showed that levels of NO2, SO2, PM10 and PM2.5 increased when the inversions strengthened. Cases of two types of diseases (acute respiratory diseases and cardiovascular diseases), which are linked to atmospheric air pollution, were considered on number of patients under 15 and above 60 years old at National Geriatric Hospital and National Otorhinolaryngology Hospital. There was significant increase in the daily average number of hospital visits with increasing surface-based inversions. The statistical analysis showed that the temperature inversions correlated with concentration of air pollutants and the number of patients in 5 years.