| |
Software Requirements
Microsoft Internet Explorer 5.01 or higher and Netscape Navigator 4.75 or higher are recommended. |
|
 |
J.Health Sci.,45(5), 276-281,1999
Modifier of Mutagenicity of Tap Water [in Japanese]
Yoshiko Hamada, Tomio Nozaka, Yoshio Nakagawa, Hisao Morita, Yoshifumi Hirose and Akio Tanaka
Saitama Institute of Public Health, 639-1 Kamiokubo, Urawa 338-0824, Japan
Previously we reported the mutagenicity of drinking water using Salmonella typhimurium TA100 and TA98 with and without S9 mix, and suggested that mutagens might be produced by the chlorination process. It is quite important to determine factors present in our environment affecting the mutagenicity of drinking water. Therefore, as a further study, modifiers of the mutagenicity of drinking water were investigated including dismutagens in order to invent means of the prevention of producing mutagens in drinking water. The mutagenicity of drinking water decreased as the treatment temperature of drinking water samples increased. Freezing and melting treatment of drinking water did not affect the mutagenicity of these samples. The UV irradiations of the samples reduced mutagenicity levels significantly. On the other hand the sunlight did not affect the mutagenicity of drinking water. The mutagenicity of drinking water samples decreased when the samples were treated by reducing agents such as ascorbic acid and glutathion. Especially, glutathion contained in most human tissues, reduced the mutagenicity of drinking water with 100%. It was suggested that the mutagenic compounds in drinking water are electrophilic and the conjugation of electrophiles with glutathion may represent a dismutagenic mechanism.
|
|
