Backyard Aquaponics
A place to discuss aquaponics

I guess it is a matter of degree.
Most of the blue drums people have, had the same products within them....
...
Surfacants are primarily detergents.

A high proportion of the herbicides used for these purposes were, in the past, of the triazine group—two of the most widely used were atrazine and simazine. These were popular because they were cheap, and their long term persistence meant that they would continue to kill newly germinating weeds long after the sprayers had gone. This feature, plus the fact that they were often sprayed onto hard surfaces from which they could easily be washed down drains, or directly into waterways, meant that these herbicides were increasingly being found in water.

Atrazine and simazine have now been banned for non-agricultural uses in the UK, and local authorities, their contractors, and the chemical companies have been forced to find alternatives.

Of the dozens of herbicide active ingredients and hundreds of products which are approved for non-agricultural weed control, two seem to be coming out on top of the struggle for market position; the non-residual systemic glyphosate and the residual substituted urea herbicide diuron.

The glyphosate based-product Roundup is claimed to be the worlds biggest selling herbicide(1). It is widely thought of by users as being harmless to the environment, and virtually non-toxic to applicators and others who are exposed to it.

The acute toxicity of glyphosate itself is very low. According to the World Health Organisation, the oral LD50 in the rat of pure glyphosate is 4,230 mg/kg—or 5,600 mg/kg according to Monsanto, the developers of glyphosate(2). The low acute toxicity of glyphosate can be attributed to its biochemical mode of action on a metabolic pathway in plants (the shikimic acid pathway) which does not exist in animals(3).

There is limited evidence that when glyphosate is administered in high doses over long time periods some test animals developed chronic health effects including birth defects(4). It is extremely unlikely that users of glyphosate or members of the public would ever be exposed to such high doses and the risk of similar health effects occurring in humans is generally considered to be low.

However, while glyphosate itself may be relatively harmless, some of the products with which it is formulated have a rather less benign reputation. Marketed formulations of glyphosate generally contain a surfactant. The purpose of this is to prevent the chemical from forming into droplets and rolling off leaves which are sprayed. Some of these surfactants are serious irritants, toxic to fish, and can themselves contain contaminants which are carcinogenic to humans.

The most widely used type of surfactants used in glyphosate formulations are known as ethylated amines. POEA (polyoxyethyleneamine) has been frequently mentioned as a surfactant, but in fact it refers to a group of ethylated amine products used in glyphosate formulations. Members of this group of surfactants are significantly more toxic than glyphosate. They are serious irritants of eyes, respiratory tract and skin, and have been found to contain dioxane (not dioxin) contaminants which are suspected of being carcinogenic. Accordingly, the UN FAO has set standards of 1 part per million (ppm) for levels of the contaminant 1,4 dioxane which may be present in POEA surfactants.

Monsanto states that all surfactants used in its glyphosate formulations fall well within the FAO standard. However, being aware of the irritant and toxic potential of the surfactants in general, the company has now developed new surfactants which have none of these toxic effects. Products containing the new formulants have already been released in France and Denmark, and are due to be released in the UK in June 1994(5).

Irritated public
The Pesticides Trust [now PAN UK] has received a number of complaints from members of the public who have themselves or whose pets have suffered from eye and respiratory tract irritation as a result of exposure to glyphosate-based herbicides being sprayed by council employees or contractors.

http://permits.nra.gov.au/chemrev/downloads/glyphosate.pdf
"From the information received, and the re-evaluation of existing data, the NRA concluded that the aquatic toxicity of currently registered glyphosate formulations is undesirably high and is mainly due to the surfactants in the formulations."

I guess it is a matter of degree.
Most of the blue drums people have, had the same products within them....
...