the truth behind ingesting essential oils

[vecktor]

I try to remember that absence of evidence is not evidence of absence.

to quote the word tangling of Donald Rumsfeld

Reports that say something hasn't happened are interesting to me, because as we know, there are known knowns; there are things we know we know. We also know there are known unknowns; that is to say we know there are some things we do not know. But there are also unknown unknowns — the ones we don't know we don't know."

he was dropped on from a huge height for saying this but what he said his characteristically confusing way was true.

safrole may or may not be carcinogenic in humans, it is to an extent in animals, and so to quote 'it may reasonably be expected to be a carcinogen in humans'. whether it is or not is very hard to determine. we know we don't know.

there seems rather a lot of circumstantial evidence quick googling turned up:

http://carcin.oxfordjournals.org/cgi/content/full/20/12/2331

same dna adducts in humans as in rats.
betel chewing has been epidemiologically correlated with cancer in humans.

the most interesting studies would be on workers in plants where safrole is steam distilled out of natural sources, they will be exposed to increased levels of safrole, and additionally there is the healthy worker syndrome so any increase in cancer levels amongst these workers would be very strong evidence.
there is even less solid evidence for myristicin being carcinogenic but again strongly suspecting it and treating it accordingly is probably a reasonable position to take.

it seems there are some problems here, the subject of myristicin amination, perhaps humans are rat like in their metabolism and then call on rat liver studies to support the amination hypothesis in humans.
then when it comes to carcinogenisis and formation of DNA adducts people take the position that human metabolism is different to rats and therefore the rat studies are worthless.

Agreed that the main motivation for the FDA clampdown on safrole in foodstuffs and herbal products had more to do with that other three letter organisation.

whether the risk associated with nutmeg or safrole or myrisicin is significant in the great scheme of things is difficult to quantify, given that there is everyday exposure to known carcinogens, benzopyrene from diesel exhausts, formaldehyde from furnishings, dioxin in chlorinated materials, etc

so do I think it aminates in vivo to MMDA? perhaps.

 

[Limpet_Chicken]

Vecktor, I bet the lime that is chewed with betel to base it is carcinogenic over time, long term exposure would doubtless irritate the oral mucosa, and lead to cancer over long periods of time.

 

[Tabaluga]

same dna adducts in humans as in rats.

I agree that allylbenzenes are probably somewhat carcinogenic. I think the fact that it is so hard to demonstrate this indicates that the effect is not a major process at all though. I mean, it's a pretty simmple proess to show and yet it seems to be so difficult with this group of compounds. My beef is with how science is corrupted by politics and how easy it is to manipulate the population [including the open minded folks here and scientists everyhwere] with what until a couple of years ago was ZERO proof. The research to support any of these claims in humans is less than 5 years old yet we've had the safrole myth in every part of society for decades.


betel chewing has been epidemiologically correlated with cancer in humans.

Oh don't get me started!! Betel 'research' is another one of my pet peeves. Firstly, virtually no study separates the components of betel quids in their research. This would not be hard because different cultures use betel in a very different way. For example, torres straight Islanders use betel nuts with Piper betle flowers rather than leaves. the flowers are MUCH higher in safrole, so would be much more indicative of safrole damage, yet this has never been compared to the leaf quids.
But worse even is the fact that most research papers totally ignore tobacco in their approach. The worst set of papers in this respect comes from Taiwan, where betel chewing is extremely politicised and regarded as a disgusting habit that needs to be stamped out. In taiwan virtually everyone uses tobacco in their quid. Commercial tobacco that is, which is already known to be carcinogenic. So in these papers the safrole gets lumped with all the naty effects from tobacco as well.
It is amazing what passes as science when politics are involved.



the most interesting studies would be on workers in plants where safrole is steam distilled out of natural sources

Great idea!! That would be truely interesting. Vietnam and china would be the right places for this. For a more historical approach brazil [Ocotea pretiosa] might be even more significant.


it seems there are some problems here, the subject of myristicin amination, perhaps humans are rat like in their metabolism and then call on rat liver studies to support the amination hypothesis in humans.
then when it comes to carcinogenisis and formation of DNA adducts people take the position that human metabolism is different to rats and therefore the rat studies are worthless.

Yeah, it's funny how everyone accepts the rat research inference for human carcinogenicity, but dismisses the converse inference for amination.
Personally I would expect both to have some truth. We now know that human carcinogenicity is possible at ridiculous ingestion levels and we also have plenty of anecdotal evidence to suggest amination proceeds in humans. It's the latter issue that I am workign on and will hopefully get a paper together sometime soon.


so do I think it aminates in vivo to MMDA? perhaps.

I am sure you are referring to humans only here, as it has already been proved in rats.