All three dyes are used as a visual detection. The fluorescent green and red dyes can be detected with an ultraviolet light or by a fluorometer while the blue does not have these characteristics. The dyes are safe and non-toxic, as well as biodegadable.
Sunlight also breaks down the color.
These dyes are used by public works departments, sanitary authorities, engineers, and many more to those who need to trace water. Inc. Last revised June 1, 1998. Best when viewed with the latest Microsoft Internet Explorer or Netscape Navigator browser.