- The DOST-PNRI continues to closely monitor the situation at the Fukushima-Daiichi Nuclear Power Plant. The condition in the plant remains very serious but is slowly getting better.
- As of 25 April, the radiation levels in 45 out of 47 prefectures are within the typical Japanese background levels of 50-100 nanosieverts per hour (nSv/h). Ibaraki prefecture showed a maximum dose rate of 117 nSv/h while Fukushima prefecture showed a maximum dose rate of 1,800 nSv/h.
- The Comprehensive Nuclear Test Ban Treaty Organization (CTBTO) air monitoring station in the Philippines being serviced by the DOST-PNRI detected the following radioactivity concentrations (in table and graph):
|
Day |
Iodine-131 |
Cesium-134 |
Cesium-137 |
|
March 23 |
33 |
4.2 |
5.7 |
|
March 24 |
480 |
92 |
120 |
|
March 25 |
54 |
6.3 |
7.7 |
|
March 26 |
20 |
0.7 |
0.7 |
|
March 27 |
47 |
2.6 |
3.1 |
|
March 28 |
93 |
4.4 |
5.3 |
|
March 29 |
130 |
4.6 |
5.3 |
|
March 30 |
210 |
1.7 |
1.6 |
|
March 31 |
31 |
Not detected |
0.7 |
|
April 1 |
57 |
4.3 |
5.7 |
|
April 2 |
61 |
9.9 |
12 |
|
April 3 |
160 |
86 |
100 |
|
April 4 |
79 |
53 |
79 |
|
April 5 |
51 |
18 |
20 |
|
April 6 |
21 |
8.7 |
11 |
|
April 7 |
12 |
4.2 |
4.6 |
|
April 8 |
73 |
23 |
28 |
|
April 9 |
95 |
22 |
25 |
|
April 10 |
140 |
21 |
26 |
|
April 11 |
80 |
16 |
20 |
|
April 12 |
53 |
8.1 |
11 |
|
April 13 |
45 |
13 |
17 |
|
April 14 |
30 |
17 |
21 |
|
April 15 |
26 |
16 |
21 |
|
April 16 |
23 |
22 |
28 |
|
April 17 |
21 |
17 |
21 |
|
April 18 |
15 |
9.4 |
14 |
|
April 19 - present |
Still being processed by CTBTO |
||
- The peak values on March 24 correspond to a dose of 131 nanosieverts in a year; sleeping next to someone for 8 hours a day for one year gives a dose of 20,000 nanosieverts because of the natural radioactivity present in the body.
- Activity Concentration of Soil Samples taken from PNRI grounds and other sites:
|
Date |
Sample Type |
Activity Concentration, Bq/kg |
||
|
Iodine-131 |
Cesium-134 |
Cesium-137 |
||
|
March 28 |
Topsoil (PNRI) |
Not detected |
Not detected |
0.064 b |
|
March 28 |
Topsoil (PNRI) |
Not detected |
Not detected |
0.175 b |
|
April 5 |
Topsoil (La Mesa Dam) |
Not detected |
Not detected |
Not detected |
|
April 5 |
Topsoil (La Mesa Dam) |
Not detected |
Not detected |
0.500 b |
Activity Concentration of Water Samples taken from various sites:
|
Date |
Sample Type/Site |
Activity Concentration, mBq/L c |
||
|
Iodine-131 |
Cesium-134 |
Cesium-137 |
||
|
April 2 |
Seawater/Sta. Ana, Cagayan |
Not detected |
Not detected |
1.66 b |
|
April 5 |
Freshwater/La Mesa Dam |
Not detected |
Not detected |
Not detected |
|
April 13 |
Seawater/Baler, Aurora |
Not detected |
Not detected |
2.70 b |
Activity Concentration of Samples taken from Cagayan Province:
|
Date |
Sample Type/Site |
Activity Concentration, Bq/kg |
||
|
Iodine-131 |
Cesium-134 |
Cesium-137 |
||
|
April 1 |
Topsoil/Gattaran |
Not detected |
Not detected |
Not detected |
|
April 4 |
Topsoil/Tuguegarao |
Not detected |
Not detected |
0.867 b |
|
April 4 |
Fish (Dorado)/Sta. Ana Fishport |
Not detected |
Not detected |
0.164 b |
|
April 4 |
Fish (Tulingan)/Sta. Ana Fishport |
Not detected |
Not detected |
Not detected |
|
April 4 |
Fish (Bariles)/Sta. Ana Fishport |
Not detected |
Not detected |
Not detected |
a microbecquerels per cubic meter; 1 microbecquerel = 1 x 10-6 becquerel
b The above Cesium-137 levels in the soil, water, and fish samples are within background levels. The Cesium-137 is residual activity from atmospheric nuclear weapons testing in the 1950’s and 1960’s, not from the Fukushima accident.
c millibecquerels per liter; 1 millibecquerel = 1 x 10-3 becquerel; some copies of Information Bulletin No.22 may have erroneously stated this as Bq/kg instead of mBq/L
d Dates corrected
- Latest DOST-PNRI RADIATION LEVEL CHECK at PNRI grounds as of 11:00 AM, 28 April 2011:
109 nSv/h, STATUS: NORMAL - The radiological and safety impact on the Philippines REMAINS INSIGNIFICANT as it had been since the beginning of the Fukushima Daiichi nuclear accident.
- For the latest information, please access the following websites:
- International Atomic Energy Agency (IAEA) (http://www.iaea.org/newscenter/news/tsunamiupdate01.html)
- Nuclear and Industrial Safety Administration (NISA) of Japan (www.nisa.meti.go.jp/english/index.html)
- World Health Organization (http://www.who.int/hac/crises/jpn/en/index.html)
- Tokyo Electric Power Company (TEPCO) (http://www.tepco.co.jp/en/press/corp-com/release/11041707-e.html)
- For further advisories, please call the PNRI trunklines with Tel Nos. 929-6010 to 19 or visit the following:
- DOST (www.dost.gov.ph)
- PNRI (www.pnri.dost.gov.ph)
- STII (www.stii.dost.gov.ph)
