Objective  To explore spatial correlation between agricultural environmental factors and lung cancer risk in five prefectures of Inner Mongolia Autonomous Region (Inner Mongolia), and to provide a reference for the prevention and control of lung cancer.

  Methods  Health records registered between October 2010 and December 2011 for the residents in 43 districts/counties/banners of five prefectures (Bayannur, Ordos, Baotou, Hohhot, and Ulan Chabu) of Inner Mongolia were collected and the data on demographics and macro economy for the regions during the period were extracted from the Sixth National Census and Social Economic Survey Yearbook of Inner Mongolia – 2012 simultaneously. Epidemiological analysis combined with space statistics was performed to assess the correlation between lung cancer risk and agricultural environmental factors and regional disparities in the correlation.

  Results  During the period among 11 271 137 residents in the five prefectures, totally 1 079 lung cancer cases were registered, with the prevalence rates of 9.57/100 000 for the all residents and 12.60/100 000 and 6.22/100 000 for the male and female residents, respectively. The results of geographically weighted regression (GWR) analysis showed that the positive correlation between lung cancer risk and agricultural factors gradually strengthened for the five prefectures of different geographical locations from southeast to northwest. Close spatial associations of pesticide, chemical fertilizer, and agricultural plastic film use with lung cancer risk were observed in a banner of Bayannur prefecture.

  Conclusion  In five prefectures of Inner Mongolia, agricultural environmental factors are associated with lung cancer risk and use of pesticides, chemical fertilizers and agricultural plastic film could increase lung cancer risk.