Study of influeces on environmental factors as for mercury methylation in Minamata Bay

2014 Fiscal Year Final Research Report

• Project/Area Number: 24350080
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Partial Multi-year Fund
• Section: 一般
• Research Field: Environmental chemistry
• Research Institution: National Institute for Minamata Disease
• Principal Investigator: MATSUYAMA Akito 国立水俣病総合研究センター, その他部局等, その他 (00393463)
• Co-Investigator(Kenkyū-buntansha): YANO Shinichiro 九州大学, 大学院工学研究院, 教授 (80274489) ; TADA Akihide 長崎大学, 大学院工学研究科, 教授 (90144328) ; NAGANO Masaaki 環境省国立水俣病総合研究センター, 主任研究員 (10393464) ; TAI Akira 九州大学, 大学院工学研究院, 特任助教 (20585921) ; IWASAKI Kazuhiro 国立環境研究所, 地域環境センター, 主任研究員 (30193717)
• Co-Investigator(Renkei-kenkyūsha): TOMIYASU Takashi 鹿児島大学, 理工学研究科, 教授 (60217552)
• Project Period (FY): 2012-04-01 – 2015-03-31
• Keywords: メチル水銀 / 総水銀 / メチレーション / 水俣湾 / 底質 / 水質 / 環境因子

Outline of Final Research Achievements

Weighted average total mercury concentration in sediment that is accumulated in current Minamata Bay is 2.3ppm, then a mass of remained mercury in Minamata bay is estimated to 3.4 ton. On the other hand, environmental factors that affected to the dissolved methylmercury concentration in seawater were estimated to temperature, salinity, DO (dissolved oxygen),DOC(dissolved organic carbon). Also,the room experiment that utilized a large aquarium(200L) was performed based on the combination experiment using these environmental factors. The combination experiment as for environmental factors are as follows: Seawater temperature 30℃、15℃,Salinity 3.0%、1.5%. Mercury concentration was 100ng/L( HgCl2 was added).　As a result, the dissolved methylmercury concentration increased using the case of 30℃ and 1.5% definitely.

Free Research Field

Environmental Science