Journal of Environmental Protection, 2011, 2, 1032-1033
doi:10.4236/jep.2011.28118 Published Online October 2011 (http://www.scirp.org/journal/jep)
Whether Increases in Ambulance Transports is
Stratified by Heat Stroke in Fukushima Prefecture,
Japan in 2011?
Nobuyuki Miyatake1, Noriko Sakano1, Shoko Murakami1, Tomohiro Hirao2
1Department of Hygiene, Faculty of Medic i ne, Kagawa University, Miki, Kagawa, Japan; 2Department of Public Health, Faculty of
Medicine, Kagawa University, Miki, Kagawa, Japan
Received July 23rd, 2011; revised August 27th, 2011; accepted September 29th, 2011.
ABSTRACT
We investigated the link between heat stroke and high air temperature from July to September in 2010 in Fukushima
prefecture, Japan. Daily data of ambulance transports stratified by heat stroke and the highest air temperature were
obtained. Heat stroke was significantly correlated with the highest temperature. The 9.0 magnitude earthquake and
following tsunami on March 11, 2011, destroyed many cities in the northwestern part of Japan. Taken together, heat
stroke may dramatically increase in Fukushima prefecture, Japan in 2011.
Keywords: Heat Stroke, Fukushima, High Air Temperature, Fukushima Daiichi
1. Introduction
Global warming has become public health challenge and
heat stroke is also considered to be a serious problem [1].
We have previously showed that ambulance transports
stratified by heat stroke was also associated with higher
air temperature in all 47 prefectures in Japan by ecolo-
gical study [2]. We found that one degree ˚C increase in
mean of the highest air temperatures in Japan corre-
sponded to a 0.122 times per ten thousand person in-
crease in ambulance transports by heat stroke in Japan
[2].
The 9.0 magnitude earthquake and following tsunami
on March 11, 2011, destroyed many cities in the north-
western part of Japan. In addition, the Fukushima Daiichi
nuclear power plant by the Tokyo Electric Power Com-
pany in Fukushima prefecture disabled their control sys-
tems. Therefore, about 4 thousand people are refugees
now in Fukushima prefecture, Japan and electric power
shortage is estimated in this summer. To show this, we
evaluated and estimated the relationship between ambu-
lance transports stratified by heat stroke and high air
temperature in Fukushima prefecture (about 2 million
people), Japan.
2. Methods
Daily incidence data of ambulance transports stratified
by heat stroke from July to September in 2010 in Fuku-
shima prefecture, Japan was directory obtained from Fire
and Disaster Management Agency, Japan [3]. Daily
meteorological parameters i.e. the highest air tempe-
rature in Fukushima, prefecture, Japan for the required
periods were obtained from Japan Meteorological
Agency. The observation spots (Fukushima city) were
located at the central in the area [4].
3. Results
A total of 947 ambulance transports stratified by heat
stroke was observed. We evaluated the relationship be-
tween ambulance transports stratified by heat stroke and
the highest air temperature by using polynomial regre-
ssion analysis. Ambulance transports stratified by heat
stroke were significantly correlated with the highest
temperature in Fukushima prefecture, Japan [(Ambu-
lance transports stratified by heat stroke) = 0.005 (the
highest air temperature)3 – 0.315 (the highest air tem-
perature)2 + 5.799(the highest air temperature) – 33.222;
r = 0.824, p < 0.0001] (Figure 1).
4. Discussion
Form our study, by using our formula of polynomial re-
gression line, we can estimate the number of ambulance
transports stratified by heat stroke. However, many fac-

Whether Increases in Ambulance Transports is Stratif i e d by Heat Stroke in Fukushima Prefecture, Japan in 2011?1033
– 5
0
5
10
15
20
25
30
35
40
45
Ambulance transports stratified by heat stroke
15 17.5 20 22.5 25 27.530 32.535 37.5 40
The highestai r t empe rature
˚
C
Per da y
n = 92
R = 0.824
p < 0.0001
Y = 0.005x
3
–0.315x
2
+ 5.799x–33.222
Figure 1. The relationship between ambulance transports
stratified by heat stroke and the highest air temperature by
using polynomial correlation analysis from July to Septem-
ber in 2010 in Fukushima prefecture, Japan.
tors are modifiable for heat stroke in this summer. Air-
conditioning may be not available due to the destruction
of the nuclear power plant and many people are refugees
now in Fukushima prefecture, Japan. Therefore, ambu-
lance transports by heat stroke may increase. It is rea-
sonable that we need to deal with high air temperatures
in summer in Fukushima prefecture, Japan i.e. individual
coping with high air temperatures, innovation of the
thermal energy metabolism in cities and preparation of
ambulance transports system.
5. Acknowledgements
This research was supported in part by Research Grants
from FUKUTAKE Science ＆ Culture Foundation, Japan.
There is no conflict of interests.
REFERENCES
[1] M. Lye and A. Kamal, “Effects of a Heatwave on Mortal-
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March 1977, pp. 529-531.
[2] N. Miyatake, N. Sakano and S. Murakami, “The Relation
between Ambulance Transports Stratified by Heat Stroke
and Air Temperature in all 47 Prefectures of Japan in
August 2009: Ecological Study,” Environmental Health
and Preventive Medicine, in press.
[3] Fire and Disaster Management Agency, Japan, in Japa-
nese, 2011.
http://jsem.umin.ac.jp/pdf/heat_qqhansouteikyou.pdf#sea
rch=
[4] Japan Meteorological Agency, in Japanese, 2011.
http://www.data.jma.go.jp/obd/stats/etrn/index.php?prec_
no=36&prec_ch=%95%9F%93%87%8C%A7&block_no
=47595&block_ch=%95%9F%93%87&year=&month=&
day=&view=