On 13th April, the IAEA Team made measurements at 7 different locations in the Fukushima area at distances ranging from 32 to 62 km, North and Northwest from the Fukushima-Daiichi nuclear power plant. At these locations, the dose rates ranged from 0.35 to 2.6 µSv/h. At the same locations, results of beta-gamma contamination measurements ranged from 0.35 to 2.6 Megabecquerel/ m2.
Analytical results related to food contamination were reported by the Japanese Ministry of Health, Labour and Welfare on 13th April that covered a total of 98 samples taken on the 4th and 11th - 13th April. Analytical results for 76 of the samples of various vegetables, pork, seafood and unprocessed raw milk in nine prefectures (Chiba, Fukushima, Gunma, Ibaraki, Kanagawa, Miyagi, Niigata, Saitama and Yamagata) indicated that I-131, Cs-134 and/or Cs-137 were either not detected or were below the regulation values set by the Japanese authorities. In Fukushima prefecture on 11th April, twenty samples of various vegetables were above the regulation values set by the Japanese authorities for Cs-134/Cs-137, and one sample of seafood (sand lance) and one sample of spinach were above the regulation values set by the Japanese authorities for both I-131 and Cs-134/Cs-137.
3. Marine Monitoring
TEPCO Monitoring Programme
TEPCO is conducting a programme for seawater (surface sampling) at a number of near-shore and off-shore monitoring locations.
On some days, two samples were collected at the same sampling point, a few hours apart and analysed separately.
Until 3rd April a general decreasing trend in radioactivity was observed at the sampling points TEPCO1 to TEPCO4. After the discharge of contaminated water on 4th April, a temporary increase in radioactivity has been reported.
On 11th April decreasing trends for both I-131 and Cs-137 concentrations of two orders of magnitude from near-shore (less than 10 kBq/l) to 15 km off-shore (0.1-0.02 kBq/l) were observed.
On 14th April no new data for TEPCO1-10 sampling points have been reported.
MEXT Off-shore Monitoring Programme
Japanese Ministry of Education, Culture, Sports, Science and Technology (MEXT) initiated the off-shore monitoring program on 23rd March and subsequently points 9 and 10 were added to the off-shore sampling scheme. On 4th April, MEXT added two sampling points to the north and west of sampling point 1. These are referred to as points A and B.