Despite the NLS Claims that "no studies exist", many do, even for fish.
Show me a single study, even just one, where a commercial fish food designed for tropical fish contains amounts of ethoxyquin even remotely close to the numbers that you have presented in the studles posted, or that have been shown to have any type of health risk to a fish.
Just one - pick a brand, any brand.
Somehow we have gone from 150 ppm which is the current max allowed in animal feed, to 25% of that 37.5 ppm and stating "contains levels way above any recommendations that would apply to you or I and well above what has been identified as being a health risk to other animals."
Exactly what studies are there that demonstrate that 30-40 ppm (if those are even real numbers within most tropical fish foods?) cause any type of health risk to a fish?
I'm well aware of all of the studies that are currently available, and unless I have missed something the only studies that I have read are ones where upper limits in ethoxyquin have been used, limits that would obviously never be found in
any commercial fish food unless that food was comprised of 100% fish meal that had been treated at 150 ppm, or greater such as the Tilapia study that you referenced, or worse, the Brown Bullhead study.
Meaningless mumbo-jumbo, as previously stated many things found in this world, including numerous
natural substances, can be lethal to a fish, or mildly toxic as you stated, when used at elevated levels.
Also, when utilizing a feed designed for a feed trial, one needs to take a very close at the control feed itself, and how that substance was utilized in that feed - such as the Brown Bullhead study. I don't know of any manufacturers that mix ethoxyquin to corn oil, then pre soak their pellets in that solution before they feed their fish. A 1.6-fold in GST activity was observed in the ethoxyquin-treated bullheads relative to control fish, but exactly what triggered that increase in GST activity, and exactly how that came about is open to debate.
I'm sorry, but I have seen this time & time again over the years where control feeds are utilized in a study that were not even in the same ball park as the commercial food that I use. High in fat, high in starch derived from terrestrial based plant matter, etc-etc, ingredients that on their own are known to cause health issues in many species of fish, and which could potentially have a synergistic effect when mixed with other substances, such as ethoxyquin.
That does not mean that one can simply extrapolate that data, and conclude that ethoxyquin at any/all levels are toxic to fish, or that at lower levels, in a completely different form than used in this single study could not actually have the opposite effect, that being a very positive health result when fed to fish. One would have to be completely daft to suggest such a thing, which is exactly what some people seem to be doing.
This takes place all the time in scientific studies, even those found in peer reviewed journals. It's very easy to reach a conclusion if one sets out to do so, based on conclusions that have already been predetermined before the study even begins.
Oh, and Kmuda, you seem to have left out the most important part of that little feed trial that involved the Brown Bullhead - it was a 0.5% formulation aka
5000 ppm, which is equivalent to 250 mg/kg/day
http://www.ncbi.nlm.nih.gov/pubmed/11399793
And once again extreme levels are used in an attempt to prove that this substance is some kind of cancer causing agent when used at appropriate levels, such as in fish food, where it has been used successfully for 50+ years. Nice try, but no cigar.
There is an old saying among nutritionists; the difference between a nutrient, a drug, and a toxin, is typically the dosage.
My issue all along as been how some people have taken some data that involves nothing even closely related to what's found in the real world, such as in commercial fish feed, and used that data to "warn" anyone that will listen that (fill in the blank) is toxic to fish. Ethoxyquin is not the enemy, but large inclusion rates of ethoxyquin, most certainly can be, just as many other components of fish food can be, including certain vitamins.
Krill contains fluoride (a known toxin to fish), many "natural" fresh/frozen foods found at the local fish market contain mercury, dioxins, PCB's, furans, and other environmental contaminants that all known toxins to aquatic life.
Does anyone honestly think that
anyone knows the exact level of Vitamin A that a tropical fish requires when kept in captivity? What about Vitamin C, E, or any of the other various vitamins & trace minerals? The same could be said about herring, krill, shrimp, spirulina, kelp, and other various forms or algae, as well as scores of other raw ingredients that millions of people world-wide feed their fish on a daily basis. Yet almost none of the thousands of ornamental species of fish (marine or fresh) kept in this hobby have ever had long-term in-depth peer reviewed studies performed to conclude exactly what each species requires in the way of optimum nutrient levels for optimum long term health in captivity, or what levels of these components would even be considered "safe".
I also see on your oscar website how you have singled out certain brands as being ethoxyquin free (such as Hikari - WTF?), and those that you somehow are certain contain it. (such as NLS) Do you own a crystal ball? lol Don't be so damn naive. NLS is the only manufacturer that actually had the stones to speak up about this topic a few years back, which has apparently now made them the whipping boy of the latest round of tree huggers. Funny stuff.
FYI - since New Life wrote that article, they have been making their own food on site, with Herring meal that is trucked in from Canada, not brought in via a ship from overseas.
IMHO most people that keep fish should be FAR more concerned about overfeeding, and the results of that, than a preservative that has been used safely & successfully for longer than most of us have been alive. (not counting me, I'm an old fart)
To quote Dr. Ruth Francis-Floyd, a professor at the U of Florida whom is considered by her peers to be an expert on fish nutrition;
"Fatty infiltration of the liver has also been designated "the most common metabolic disturbance and most frequent cause of death in aquarium fish"
And on that note I would highly recommend reading the following discussion for anyone that's concerned about the longevity of their fish.
http://www.monsterfishkeepers.com/f...-for-those-who-feed-fish-multiple-times-a-day
Cheers.