Well Bruce, as Georg and I were agreeing not long ago, the term "oil" is one of the most abused, and most loosely  used, that you can think of. "Heavy" btw is another such! It should refer to density, you might think, but somtimes it means "viscous" and other density independent adjectives.

The term "oil" in turn, refers to a wide range of compounds, most of which are in fact less dense than water, but not all. The narrowest sense is "liquid triglycerides", and all of those that spring to mind do indeed float on water, most definitely including all those that you and I would generally refer to as "vegetable oils". However, chemically speaking, many of the "essential oils" are totally different from plant oils sensu strictu, and some of those "essential oils" are denser than water. Examples include allicin and allyl- and phenyl mustard "oils".

As has been mentioned, the word "oil" is pretty generic and has a broad meaning. However there are a few examples of heavier than water oils; including in most petroleum crudes.

Crude oil is a blend of hydrocarbon molecules which range from methane with just one carbon atom (CH4) to bitumens and residues with molecules hundreds of carbon atoms long. Crude also contains significant quantities of sulphur and smaller quantities of many metals. Broadly speaking, the density of the oil increases proportionally with the increase in molecule size.

Tragically, too many times, in marine spills. the confirmation of the existence of oils heavier than water becomes apparent.

First, the light components evaporate off as vapour, other lighter components weather and degrade, and finally there is left a semi solid sticky and sometimes viscous residue, still technically oil, which sinks to the ocean floor, even in ocean water which is much denser than water out of the tap. Some authorities estimate that as much as 25% of the half billion litres of crude oil spilled in the recent Gulf of Mexico incident is now on the sea floor, where it will slowly biodegrade over the next millennium or so.

In the case of plant essences, or their distilled aromatic fluids, it is quite likely that there are molecules large enough, or contain enough heavy metal compounds, to be heavier than water.

Re the Gulf of Mexico, in the political environment during such a catastrophe as this, spokespeople and speechwriters seem to enter a surreal zone where all communication is tainted by “spin”. Basically spin is either making a virtue out of a necessity, extreme euphemism, question begging or other verbal shenanigans to make news more palatable to the public. In the academic environment the requirement for spin is not as crucial to the spokespeople and speechwriters therefore on many occasions the emphasis of such news tends to diverge somewhat from the political emphasis.

Hence generally the politically spun reports of the Gulf of Mexico recovery state that all but 26% of all the oil spilled had been recovered, as follows, Direct recovery from wellhead 17%,  Burned at the surface 5%, Skimmed from the surface 3%, Chemically dispersed 8%, Naturally dispersed 16%, Evaporated or dissolved 25%, Residual remaining 26%.

Ian MacDonald, an ocean scientist at Florida State University, claims the NIC report "was not science". He accused the White House of making "sweeping and largely unsupported" claims that three-quarters of the oil in the Gulf was gone. "I believe this report is misleading," he said. "The imprint will be there in the Gulf of Mexico for the rest of my life. It is not gone and it will not go away quickly." In August, other scientists from the University of Georgia had determined that as much as 79 percent of the oil remains in the Gulf of Mexico, under the surface. This was reported in Bloomberg.

I was in fact trying to make my comment a little bit more palatable by finding the report with the least catastrophic prognosis. As you correctly point out, there are such conflicting claims, most of them also conflicting with subsequent news reports, that I also am pretty reserved about accepting any of them unconfirmed. The most reliable estimates more recently available state that almost 700 million litres escaped of which about half has evaporated, burnt or been recovered.

It’s certainly true that bacterial organisms can and do biodegrade oil from the seeps and other sources around the world. But they themselves consume oxygen and with the seeps flowing at the present rate all is well. However providing the microbes with a banquet of 350 million litres over a period of about three months is a different matter. Growing enough of them to eat all that oil will reduce oxygen levels so much that it is possible no life at all will be able to exist in the spill area for centuries. I certainly take no pleasure in forecasting such a possibility but if we leave all distribution of information up to the pollies we get nowhere. May I mention Wikileaks as the perfect exemplar.

While some trace elements ( they are not all “heavy” metals, of course ) are still being discovered and their effects are still being studied, researchers have determined that the following trace elements are vital to the health and well-being of humans, animals and other organisms alike: Aluminum, antimony, barium, beryllium, bismuth, boron, bromine, cadmium, caesium, cerium, chromium, cobalt, copper, gallium, germanium, gold, indium, iodine, iridium, iron, lanthanum, lead, lithium, magnesium, manganese, mercury, molybdenum, nickel, niobium, osmium, palladium, platinum, radium, rubidium, selenium, silicon, silver, strontium, tellurium, thallium, thorium, tin, titanium, tungsten, vanadium, zinc and zirconium.

I had a thought that as all herbivores require at least all of these, and they certainly don’t respire them, it seemed to follow that the food they consumed must contain them. In any case all plants are organisms, and therefore contain these in varying amounts. Then it seemed to follow that the fractions distilled from the separated plant liquids may just happen to contain compounds of these elements which were of a greater density than water. So in answer to your question: any or all of them. Whatever the roots take up must be soluble, and certainly the extraction process will include them.

And an awful lot of the distillates are oils. Ever heard of any of these? http://oilganic.com/essential-oil-glossary/essential-oil-list.htm

Oil of Cloves, for one, contains about 90% Eugenol, and though it is a phenylpropene and does not contain heavy metals, is heavier than water.

In 1993–94 the International Symposium on Medicinal and Aromatic Plants determined the content of Cd, Pb, Cu, Mn, Zn and other trace elements in essential oils and plant extracts from the genera Rosa, Lavandula, Mentha, Salvia, Ocimum, Foeniculum, Coriandrum, Anethum, Hyssopus and Rhus, produced in Bulgaria.

Results, obtained from two apparatuses (appariti ??) were very similar. They found that the concentration of the most hazardous heavy metals in all of the tested oils and plant extracts was very low, near the detection limits of the apparatuses used. It was concluded “that most of the essential oil and medicinal crops could be successfully grown on heavy metal polluted soils and under atmospheric pollution as substitutes for some other edible crops”. Obviously this means that these plants contain and yield heavy metal compounds wherever they grow.                                                        

I am looking forward to perusing your evidence to the contrary.  

As for the connection between the essential oils and petroleum, I was merely suggesting the possibility that metallic compounds would increase the density of the vegetable product just as they do of petroleum.  

YM, beware of speaking too glibly of “trace elements”. You and I certainly are full of trace elements, but it does not follow that most of them are beneficial, much less essential. If you wish to include all of them, you have not done well; do me a favour! I could expand your list with my eyes closed. You are neither a chemist nor a biologist are you?

For a start, the relevant elements are neither trace elements nor essential trace elements; they are nutrient trace elements, some of which (largely non-PC ones) you omit, I observe. Others are not trace elements by any criterion (magnesium, I beg you!) In mammals others are only arguably trace nutrients.

What is worse, you seem to have been regurgitating the kind of rubbish that abounds on “organic” sites and the like.

This is distinctly embarrassing YM. Not everyone in the forum is dead ignorant of elementary nutrition theory you know!

You say: “While some trace elements ( they are not all “heavy” metals, of course ) are still being discovered and their effects are still being studied…” Well, we need hardly quibble about the heaviness of the elements; it is only relevant in limited contexts, so we can afford to ignore that point. But you really should be more cautious about spilling your drink when doing your hand waving. They are not “still being discovered” as you put it, unless you wish to include the likes of unununium, which I assume you do not; after all you didn’t even mention promethium or technetium.

>researchers have determined that the following trace elements are vital to the health and well-being of humans, animals and other organisms alike<

If I am to answer that as a blanket statement, I must contradict you flatly. They have done nothing of the kind. You certainly have included a number of essential trace nutrients, such as iodine, selenium and zinc, but most of your list has not been shown to be essential at all, and most in fact are about as essential as astartine. It is not an easy matter to demonstrate that candidate sub-micronutrients are nutrients at all YM! The arguments for most of those on your list amount to asserting negatives: “How can you prove that they aren’t?” That sort of thing. Consider some of the really stupid examples, in the light of your personal specialist knowledge: Al? Do you remember the time they discovered that it is the causative factor behind Alzheimer’s? At least that was a slip that got nicely retracted and explained. In fact, far from mocking the errant parties, I value their contribution to the kind of thinking that should be standard in such work.

Now, let’s see you do a bit of thinking on the subject. Describe to us how you would go about demonstrating that Al is vital, will you? Simple hm? All you have to do is exclude Al from the experimental subjects, right? Errr… OK… We have created an Al-free environment, without which we simply cannot proceed. Good. How did you manage that? No glass in the place? I don’t remember the last piece of glass that I saw that was free of Al… Nor the last brick or cement. Nor the last breath of air that contained no Al dust. It is about the third commonest element in the crust if I remember correctly. Am I missing any? And if you did miraculously exclude all Al, what would it mean if your experimental subjects failed to thrive? How would you go about excluding all Al without destroying the food’s value or rendering it poisonous?

Some members of your list are so fanciful that I am convinced some idiot just ran through a periodic table and grabbed the ones with nice names. And can you see some difficulties with Sr and Rb for examples? And Os? Ir? Ra?

>Aluminum, antimony, barium, beryllium, bismuth, boron, bromine, cadmium, caesium, cerium, chromium, cobalt, copper, gallium, germanium, gold, indium, iodine, iridium, iron, lanthanum, lead, lithium, magnesium, manganese, mercury, molybdenum, nickel, niobium, osmium, palladium, platinum, radium, rubidium, selenium, silicon, silver, strontium, tellurium, thallium, thorium, tin, titanium, tungsten, vanadium, zinc and zirconium. <

YM, do us a favour!!!

Dat’s good t’inkin’ YM, except for the fact that for well over half of them there is no question of their being nutrients at all, and far less question of their being essential. You simply could not demonstrate it in any of the least plausible cases by the traditional methods of controlled exclusion and inclusion of the elements. It would at the very least require two conditions: the existence of a metabolic pathway dependent on an element, and demonstrations that no alternative elements that could achieve the same effects. I challenge you to find a single case of those conditions being fulfilled in the likes of say, thallium, thorium or platinum or any of the sillier cases in general. Watch out for the likes of Sr for example; we contain plenty of it, but it seems to be more of a harmless impurity in Ca than a necessary nutrient in its own right. Arguments for Cs and Rb are hardly stronger.

>I had a thought that as all herbivores require at least all of these, and they certainly don’t respire them, it seemed to follow that the food they consumed must contain them<

No doubt YM, but they don’t. You have been misled by some glib fringe quackery.

>In any case all plants are organisms, and therefore contain these in varying amounts. Then it seemed to follow that the fractions distilled from the separated plant liquids may just happen to contain compounds of these elements which were of a greater density than water. So in answer to your question: any or all of them. Whatever the roots take up must be soluble, and certainly the extraction process will include them.<

YM, you could hardly demonstrate more plainly how far you are out of your depth. I will not dismantle your arguments piecemeal, but point out instead that the compounds in question are pretty well characterized chemically. I cannot offhand think of any “essential oil” that contains a metallic atom, heavy or light. They include a wide range of molecular classes, such as ethers, esters, olefins, phenols, polyphenols, terpenes ( real rag-bag that one!), aldehydes, ketones, isothiocyanates, cyanides (nitriles if you like), various enantiomers… you name it.

But organometals? Even demonstrated micronutrients? Even demonstrated macronutrients… Ahah! My thanks to you for a partial counterexample: Chlorophyll! It isn’t an essential oil, it does not occur in the list you supplied a link for, and I never have worked with it myself, so I cannot vouch for this, but it does contain the (macro-!)nutrient magnesium! And I understand that it has a definite, rather pleasant smell.

>And an awful lot of the distillates are oils. Ever heard of any of these?<

Many of them actually. Have you? I am left in doubt. For one thing, which of them did you think was an oil? I haven’t been through the whole list, but I saw not one, and Ishould love to be proved wrong. And which of them contains any metal atoms? (That should be a good one!)

>Oil of Cloves, for one, contains about 90% Eugenol, and though it is a phenylpropene and does not contain heavy metals, is heavier than water.<

Errr… Really YM? That is a novel item of evidence! I take it you have not read the rest of this thread?

>In 1993–94... produced in Bulgaria... found that the concentration of the most hazardous heavy metals in all of the tested oils and plant extracts was very low, near the detection limits... most of the essential oil and medicinal crops could be successfully grown on heavy metal polluted soils ... as substitutes...”. Obviously this means that these plants contain and yield heavy metal compounds wherever they grow. I am looking forward to perusing your evidence to the contrary.<

Look forward in good health YM; As it happens I have an idea that I actually have seen that very publication and I have no quarrel with it at all. A very good, constructive idea I thought. However, you make it embarrassingly obvious that you didn’t even understand what they were doing or demonstrating. Notice what the levels of detected metals were! Ask yourself what they had to do with the “oil” molecules. They were contaminants, not components! The essential oils of “Lavandula, Mentha, Salvia, Ocimum, Foeniculum, Coriandrum, Anethum, Hyssopus” certainly do not contain heavy metals in their structure, nor light metals at that! I don’t know what kind of Rhus they grew, but if you can find any evidence of Rhus essential oils with heavy metal components, please tell us aaallll about it!

Thanks for your contribution,

Jon

First of all we must, it seems, have a look at the meaning of the word “essential”. While it is true that its meaning has been broadened relatively recently to mean “greatly necessary” or “indispensable”, its use in the context of the fragrant distillates of vegetable fluids is more to convey the fact that they are the essence, extract or concentrate of those fluids. The name has no connection to whether the plant needs them or not, merely that they have been distilled from the plant’s circulatory fluids and secretions.

And I certainly did not state that the trace elements were essential, as I do not normally use the word to convey meaning “a” above. I did use the word vital, quoting Wikipedia. Anyway let’s move on from semantics. Your reflexes getting off the mark to disparage diet supplementers show no signs of decay. Are you sure you don’t augment those antioxidants just a bit ?  

Having hopefully got that out of the way, the average masses of various elements in the body of a 100 Kg human. ( Quantities are Kilograms ) are:

Oxygen 65, Carbon 18, Hydrogen 10, Nitrogen 3, Calcium 1.5, Phosphorus 1, Potassium 0.25, Sulphur 0.25, Sodium and Chlorine 0.15 each, Magnesium 0.05, Iron 0.006 plus another 58 or so elements including radium, arsenic, radium and gold to make up the last three quarters of a kilo.

Four kilograms of these metals and sulphur is enough to sink us very quickly in fresh water, less quickly but just as surely in normal seawater, as soon as we exhale. All fish have air bladders to float them; sharks need to swim to keep them off the bottom. If we were all nought but oxygen, water, hydrocarbon and nitrogen how could this be ?

The suggestion that these and the other rarer metals are contaminants is preposterous. It is true there is plenty of research yet to be done but really it’s a bit premature to call them that ! They just may all have a reason to be there. Certainly diet supplement manufacturers make vast fortunes convincing people that our diets do not contain enough of them, much to the chagrin of one prolific answerer of “Last Word” correspondence.

The vast majority of humans and all wild herbivores get quite enough thank you from the primary food available. This by definition is vegetation. Some domesticated animals receive supplements but that tends to be more to encourage weight gain than for subsistence.  

Just a last point, and one that I hesitate to mention here because I realise one sunny day does not a summer make, but the matter of aluminium in the diet is a very touchy one with me. As far as I’m concerned the jury is till out on aluminium. My mother has just turned 90 and is in the extremity of Alzheimer’s. In the five year period starting 1994 she suffered from gastro-oesophageal reflux disease, and was being treated with many and various concoctions of aluminium hydroxide and aluminium oxide. She finished up taking sometime 10 or 20 grams of the stuff a day ! I was aware of the insolubility of aluminium salts and the prevailing medical view that little aluminium was absorbed after swallowing the treatments, but I actually wrote a letter to the Sydney “Bulletin” at the time in the hope that someone may have done some studies of geriatrics taking megadoses of indigestion cures to see it there were in fact any trends appearing.

I also told Mum to ask the doctor if there was any alternative medication as I felt she was taking too much, and immediately he prescribed a drug to make the sphincter muscle more effective. As far as I know she didn’t take antacids again. I can remember as a child seeing suspended bits of metallic aluminium in the custard saucepan if the one stirring it got overzealous with the scraping, and alum has been used as a flocculent in water treatment plants for decades, and little harm seems to have been done. All the same I look at Mum’s isolation and fear of us strangers and will take a fair bit of convincing that the ingestion of aluminium in the quantities that she took over a five year period maybe was not all as harmless as the manufacturers would have us believe.