Ethan, Crystal Jane
Mokoena, Kingsley Katleho
Yu, Yan
Shale, Karabo
Fan, Yameng
Rong, Jie
Liu, Feng
Article History
Received: 19 June 2019
Accepted: 26 March 2020
First Online: 20 April 2020
Compliance with ethical standards
:
: The authors declare that they have no competing interests.
: The main strengths of the study include (1) exploring both single and multi-pollutant models in the association of PM<sub>2.5</sub> and both stomach and colorectal mortality, and (2) stratifying association results by gender and age. The present study had few limitations, the major one being the unavailability of data from all districts of Xi’an. Data was only available for 6 districts which were mostly urban areas. Secondly, as with most studies, the pollution level was based on city-wide averages and not personal exposure level (since the use of personal exposure monitors are expensive in China). This challenge may limit knowledge of the precise effect of the pollutants since concentration levels can vary from location to location.