I do try to be an advocate for a natural pond and post my small experiments and what has worked for me. Using a herbicide with a warning label for non aqua use isn't what one should ordinarily do. But there are times when approved labels can be terribly wrong. I have lived long enough to see a lot of them. When you mentioned labels are law many thought went through my mind. Here are a few.
My farmer used a spray that drifted to the house and I couldn't get my breath. He quit using it because he experienced the same thing.
As a pattern model maker we used different two part plastics. We got a new one that we used for a couple of hours when 20 patternmakers in the shop started having their fingers, ears, lips and faces go numb. There was nothing on the labels about this.
As a model maker we used a certain two part plastic and two of our guys became sensitized so bad they could only do wood pattern work. The plastic corporation, REN, sent in high powered execs to say their product didn't do this, but in the end they admitted to it. Again labels didn't have this warning.
A guy I worked with's pregnant daughter in-law took Thalidomide as an anti-nausea before it was taken off the market and the baby was born without legs or arms. Again the labels didn't protect.
My cousin's husband is a Vietnam veteran was told that the Agent Orange sprayed jungles were safe for them to be in. He now has leukemia and the government later admitted cancer was being caused by agent orange.
Also, Birth Defects Caused By World's Top-Selling Weed killer, Scientists Say ... As recently as last year, the German Federal Office for Consumer .... ban on the use of glyphosate
http://www.huffingtonpost.com/2011/06/24/roundup-scientists-birth-defects_n_883578.html
