Background: Emission from rice straw burning (ERSB) is observed everywhere
after harvest of rice in Niigata Prefecture every year. Pediatricians and m
any guardians in this district have had the impression that ERSB may induce
asthma attack. Recent studies have suggested that particulate air pollutio
n plays a role in the exacerbation of asthma. The authors investigated rela
tionship of ERSB to asthma attack in children.
Methods: A questionnaire on rice straw burning (RSB) was circulated to guar
dians and pediatric institutions. Change in the monthly number of children
with asthma attack (CAA) for 5 years from January 1994 to December 1998 was
investigated. In addition, change in the number of CAA from the meteorolog
ic conditions and RSB was investigated from the fourth week of August to th
e third week of September in 1996, 1997 and 1998. Challenge test exposure t
o ERSB was tried on a volunteer adult with chronic asthma. The situation of
air pollution was examined by measuring suspended particulate matter (PM10
). The relationship between PM10 and the number of CAA was studied.
Results: A majority of the guardians had the impression that ERSB induces a
sthma attack. Pediatricians replied similarly to the questionnaire. The num
ber of CAA visiting our emergency room and admitted to our ward increased i
n the season of RSB. The PM10 had a significant correlation with the number
of CAA. It was suggested that the increase in CAA may be not due to the me
teorologic conditions, but to the influence of ERSB.
Conclusion: The ERSB has made an issue of air pollution. Furthermore, the p
ossibility that ERSB induces or exacerbates asthma attack has become clear
in the present study. Therefore, it is recommended that RSB should be aboli
shed for the health of inhabitants, especially children with asthma.