Marine radioactivity of Cs-134 and Cs-137 in the Malaysian Economic Exclusive Zone after the Fukushima accident

Seawater, sediment, biota and seaweed samples were collected in the Malaysian Economic Exclusive Zone (EEZ) marine environment within April 2012 to April 2014 as part of the marine radioactivity monitoring activities following the Fukushima Daiichi Nuclear Power (FDNPP) accident. The objectives of this study were to quantify radioactivity releases of Cs-134 and Cs-137 from the FDNPP into the Malaysian EEZ marine environment and to evaluate its potential impact on radionuclide levels in the marine life. The results showed Cs-134 in seawater, sediment and; biota and seaweeds were ranged from 1.3 to 2.2 Bq m−3, 1 to 1.9 Bq kg−1 dw. and < 0.01 to 0.2 Bq kg−1 fw., respectively. The levels of Cs-137 and Cs-134 as a radioisotopic signature for FDNPP discharges indicated that no new inputs into Malaysian marine environment, thus definitely confirmed the radioactive water released from FDNPP accident does not contaminate our marine environment. The estimated total dose and risk quotient using ERICA Assessment Tool showed the Cs-137 activity concentration in Malaysian marine environment was far below the screening value and does not cause any risk to the living organism. Thus, all our seafood including seaweeds are safe for human consumption.