Physical and chemical characteristics of PM and its toxicity to human bronchial cells BEAS-2B in the winter and summer.

With the increasing occurrence of haze during the summer, the physicochemical characteristics and toxicity differences in PM in different seasons are of great concern. Hangzhou is located in an area that has a subtropical monsoon climate where the humidity is very high during both the summer and winter. However, there are limited studies on the seasonal differences in PM in these weather conditions.