Backyard Aquaponics
A place to discuss aquaponics

Clove Oil vs. Eugenol

Clove oil is actually a mixture of different compounds. The three significant active ingredients are eugenol, isoeugenol and methyleugenol. 'Clove oil' is 85 to 95% eugenol. Isoeugenol and methyleugenol make up 5 to 15% of the remaining ingredients. Isoeugenol is the compound considered by some aquaculturists to have the best anesthetic effect. However, neither clove oil nor any individual active ingredient of clove oil (eugenol, isoeugenol, or methyleugenol) is approved for use for the anesthesia of fish.

2 Approval Status

Clove oil has been affirmed as Generally Recognized as Safe (GRAS) as a substance added directly to human food (21 CFR 184.1257).

Eugenol is GRAS in animal feed (21 CFR 582.60) and isoeugenol is cleared for use in human food (21 CFR 172.515). Both compounds are listed as synthetic flavoring substances and adjuvants.

Eugenol (not clove oil) is used as a component in dental cement for temporary fillings (21 CFR 872.3275). It is considered a device exempt from premarket notification procedures.

The fact that clove oil or its components are GRAS for use in dental cement or as food additives under these conditions does not justify the use of these products as new animal drugs.

Neither clove oil nor eugenol is approved as a new animal drug to treat or mitigate any diseases in any species in the U.S. Therefore, the use of either clove oil or eugenol as an anesthetic for fish makes them unapproved new animal drugs.


3 Anesthetic Choices for Use in Fish

MS-222 (FinquelÒ or Tricaine-SÒ), also known as Tricaine methanesulfonate are approved new animal drugs that can be used as an anesthetic in fish. The conditions of use for this drug can be viewed at http://dil.vetmed.vt.edu/AdvancedNADA/N ... ng=042-427 and http://dil.vetmed.vt.edu/AdvancedNADA/N ... ng=200-226.

In addition, carbon dioxide gas may be used as an anesthetic for cold-, cool-, and warm water fish and sodium bicarbonate may be used as an anesthetic on all fish (the sodium bicarbonate is principally an alternate source of carbon dioxide). The use of carbon dioxide gas and sodium bicarbonate as anesthetics makes these compounds new animal drugs. At this time, however, the Agency has chosen not to take regulatory action for the above use of these compounds. Details about the uses of these two compounds can be found at (http://www.fda.gov/cvm/index/aquaculture/LRPDrugs.pdf).


4 Human Food Safety

Clove oil and isoeugenol have been used in foods and eugenol has been used in animal feeds. Concern for this class of chemical compounds led to the nomination of eugenol, isoeugenol, and methyleugenol for investigation under the National Toxicology Program (NTP). The NTP conducts studies in nominated drugs and chemicals to determine their potential to produce cancer. Studies have been completed for eugenol and methyleugenol, and are planned for isoeugenol. NTP determined that eugenol is an equivocal carcinogen and methyleugenol is carcinogenic to rodents. The contamination of clove oil with methyleugenol or isoeugenol raises the level of concern for human safety.


You can see the status of toxicology studies conducted on these compounds by going to the NTP website at http://ntp-server.niehs.nih.gov/. Once there, use the search function. A search for 'eugenol' brings up all the related test results.

Wot r u suggesting they b trained 2 do Frank? Training the big ones to eat at one time and the smaller at another

just not sure it's worth the time and effort though...

A 2mm pellet would feed a fish with a 4mm mouth.... say 50-80mm... (for the sake of illustration)
Whereas a 25-40mm fish would need a crumble... or 1mm pellet...

the whole objective of my suggestion for training fish is to avoid having these differences in one tank

One option, of course is to grade and feed accordingly:
Have narrowly spaced bars, and if the fish can swim through them, they get to the finer feed first.
The next set of bars allow medium and small fish to get to the less fine feed next, then the course feed is dumped in the tank. That way, you can grade your fish (ring the dinner bell, and all the smaller fish go grab their dinner, and you grab the bigger ones.)
Automated training would be best, and I think that you could do it using the same system that aquaculturists use for grading the fish (progressively smaller spaced bars). The only thing is that you'd have to have a way to remove the grading bars after the feeding, or the fish would get fat and not be able to get back out after eating.

I would contend Frank, that that's probably just not possible....

I even offered a method (on-demand pendulum feeders) of "training" the fish to resolve one of the management issues...

There is no better sight than a whole mob of fish jumping for feed...I put forward attestations from EB, Faye, C1, OBO, our american forumers with tilapia, etc.......

but to those others, why not just toss on a measured quantity of food - the big ones jump in and get their fill first
...next toss in another measured qty of food...continue until all fish fed
by having the pellets spread over the whole of the fish tank allows for a multitude of fish to feed at the same time also

...just some simple alternatives

So skeptics, please give us a chance
you stand nothing to lose:
if we fail you glory
if we succeed you will be able to apply it