Clarification on the Genotoxicity of Effluents from Johkasous and Reduction Effects by Several Treatments such as Chlorination

2014 Fiscal Year Final Research Report

• Project/Area Number: 24710079
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Environmental technology/Environmental materials
• Research Institution: Nagasaki University
• Principal Investigator: KUBO Takashi 長崎大学, 産学官連携戦略本部, 助教 (40397089)
• Research Collaborator: BAI Wenzhi 長崎大学, 水産・環境科学総合研究科
• Project Period (FY): 2012-04-01 – 2015-03-31
• Keywords: 遺伝子毒性 / 浄化槽 / umu試験 / バイオアッセイ / 固相抽出 / 塩素処理

Outline of Final Research Achievements

Concentration methods for the genotoxicity test of effluents from johkasous were decided and the genotoxicity of domestic wastewater in several model areas were investigated by using the methods. As a result, the order of intension of the genotoxicity was as follows; Gappei-johkasou > Tandoku-johkasou ≒ Community plant ≫ Vault toilet. The genotoxicity varied more than 10 times depending on the treatment methods and sampling sites. Moreover, it was revealed for the first time that the values of the genotoxicity in the present study were several ten to hundred times higher than that of Japanese typical tap water. In addition, reduction of the genotoxicity using several reagents was attempted. However the results were different from expectations. As for reactions with chlorine, it was shown that the genotoxicity became stronger if free chlorine was added further after ammonia nitrogen had almost disappeared by a reaction with free chlorine.

Free Research Field

環境安全学