Environmental fate of thionated phenylarsenical compounds

2015 Fiscal Year Final Research Report

• Project/Area Number: 25340084
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Modeling and technologies for environmental conservation and remediation
• Research Institution: Niigata University
• Principal Investigator: HARADA NAOKI 新潟大学, 自然科学系, 准教授 (50452066)
• Project Period (FY): 2013-04-01 – 2016-03-31
• Keywords: ジフェニルアルシン酸 / チオ化 / 硫酸還元菌 / 嫌気的微生物変換 / 水稲

Outline of Final Research Achievements

In this study, we isolated Desulfotomaculum acetoxidans strain DEA14, which could anaerobically transform diphenylarsinic acid (DPAA) to diphenylthioarsinic acid (DPTA). A known sulfate-reducing bacterial strain, Desulfovibrio aerotolerans JCM 12613T could also transform DPAA to DPTA. The findings suggest that H2S produced by sulfate-reducing bacteria has a role in thionation of DPAA under anaerobic soil conditions. In addition, we confirmed that other phenylarsenicals, such as diphenylmethylarsine oxide and phenylarsonic acid, could be thionated by reaction with H2S. Uptake of phenylarsenicals in rice was also investigated under flooded conditions. At the harvest, DPTA was found in the soil and root samples. In the leaf, stem and brown rice samples, As(V), DPMAO, PMAA and/or DPAA were detected. The results indicate that arsenical species found in rice vary at different parts and the aerial parts of rice contain no DPTA.

Free Research Field

土壌学、土壌微生物学