Table 7.

Estimated results of mechanism analysis.

Explanatory variable	Explained variable: Perinatal mortality
	(1)	(2)
Average PM2.5 (log)	0.433
	(1.307)
w5* Average PM2.5 (log)	0.626**
	(0.265)
Max PM2.5 (log)		0.807
		(0.939)
w5* Max PM2.5 (log)		0.652**
		(0.268)
w5	− 1.085	− 1.387
	(0.922)	(0.977)
Urbanization	− 0.003	− 0.000
	(0.019)	(0.018)
GDP per capita(log)	− 6.034***	− 5.766***
	(1.912)	(1.934)
bed_pop	0.021	0.012
	(0.055)	(0.054)
ha_pop	− 0.040	− 0.039
	(0.042)	(0.039)
Constant	33.247***	30.869***
	(6.468)	(6.664)
Year fixed effects	Y	Y
Province fixed effects	Y	Y
Within Rsquared	0.773	0.774
Observation	434	434

Standard errors in parentheses. *p < 0.1, **p < 0.05, ***p < 0.01.