*SUSHMITA HOSSAIN^1,2、Asma Akter⁴、Shirin Akter²、Yeasmin Nahar Jolly²、Bilkis Ara Begum²、Takashi Ishiyama³、Shoichi Hachinohe³、Aziz Hasan⁴、Kazi Matin Ahmed⁴ (1.Graduate school of Science and Engineering, Saitama University, Japan、2.Chemistry Division,Atomic Energy Centre,Bangladesh Atomic Energy Commission,Bangladesh 、3. Research Institute,Center for Environmental Science in Saitama,Japan、4.Department of Geology,University of Dhaka,Bangladesh)