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PG UPDATE- TOXIC

herbivore21

Well-Known Member
Just found this and needed to share!!

The dangers of vaping PG, PEG and VG!!

https://www.projectcbd.org/article/update-toxic-marijuana-vape-oil-additives-endanger-patients
I have pointed out the toxicity of PG, PEG and VG on FC for over a year now brother. This is information that has been suspected for years now. Sadly, many seem to have ignored for a long time since it has been known. Over the last year, it has been demonstrated that VG and PG are not safe to heat and inhale for more reasons than those cited in the projectcbd article above.

Please, everybody, as I've said for a long time, do not use ejuice at all. It is redundant (there are more essential oil only vape options than ever before!), it makes your concentrates taste worse, not better and it is known to be unsafe to heat and inhale in ecig tanks.


Guess we should just use VG?

"And vegetable glycerin did not produce detectable amounts of any of the toxins studied."
Sadly, no. VG is known to release Glycidol, a probable carcinogen when it is vaporized in ecig tanks. I've shared the peer reviewed studies elsewhere on FC long ago.

The ProjectCBD release above does not highlight the other toxic/probably carcinogenic compounds released by PG as well - propylene oxide.

I'll share a study evidencing Propylene Oxide and Glycidol among other irritants and carcinogens found in vg/pg that I shared once a while back here for you guys to consider:

http://pubs.acs.org/doi/abs/10.1021/acs.est.6b01741

Cribnotes - DO NOT USE EJUICE/VG/PG/PEG. THERE IS A GROWING BODY OF RESEARCH IDENTIFYING THAT THIS IS DANGEROUS.

* Please note that ecigarettes using ejuice are still considered safer than conventional tobacco smoking. If you are using ecigarettes and ejuice to quit smoking cigarettes, then this is not necessarily the same kind of problem - just be mindful that ecigs are still harmful, even if less so.

My comments above apply to ejuice when used for cannabis. Especially in the medical context, I know many like to use it as it is convenient but this is just not safe. Don't risk it, we don't need to mix these solvents with our extracts anymore, there's plenty of purpose-made oil vapes.
 
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seaofgreens

My Mind Is Free
Hey @herbivore21

I can't read the whole study, and am curious about the data!

Are you able to access the quantities of carcinogens present in the data?

Also if/what thresholds these toxins are set at in terms of what is ruled safe for ingestion, and how these liquids compare to those thresholds?
 

guyonthecouch

Well-Known Member
Please, everybody, as I've said for a long time, do not use ejuice at all. It is redundant (there are more essential oil only vape options than ever before!), it makes your concentrates taste worse, not better and it is known to be unsafe to heat and inhale in ecig tanks.
What are healthier options for thinning/carrier agents for making oils?
 

herbivore21

Well-Known Member
Hey @herbivore21

I can't read the whole study, and am curious about the data!

Are you able to access the quantities of carcinogens present in the data?

Also if/what thresholds these toxins are set at in terms of what is ruled safe for ingestion, and how these liquids compare to those thresholds?
I believe these were addressed in the other thread I made about that study on FC a while back. I don't have time to search for that right now but I'm sure you'll find it easily enough with a search :) If you would like more detail I can set aside some time later to look back at the study and give you the info (busy now). I do recall that the study found greater levels of the offending compounds at greater voltages. Also dual coil ecig tanks tended to produce lower volumes of the offending compounds than single coil ecigs at the same voltage, due to the voltage/current being dispersed across a greater surface area, resulting in lesser overall temp.

What are healthier options for thinning/carrier agents for making oils?
If you are asking this question, what I gather is that you are trying to shoehorn cannabis extracts into ecig tanks designed to consume eliquids. Cannabis extracts are not liquids, and so ecig tank style carts are not appropriate for cannabis concentrate consumption. Unless you can make your own high quality distillates in the right consistency (don't try that at home, please!), you should be looking for vaporizers that are made to work with straight cannabis extracts in their original consistency. Look at the many abundant oil pens, as well as the flower vapes that allow us to use concentrates with a concentrate pad or similar. You'll get much better results that way.

E-nails are the best way to consume oils. To a lesser extent, I use a puffco plus for rosin/shatter/etc on the go, and an Omnivap with concentrate pads for full melt etc which doesnt work in pens. Hopefully these suggestions will give you a few options to consider for your concentrate needs that don't necessitate ejuices :)

I do not recommend mixing concentrates with ANY carrier agent.
 

seaofgreens

My Mind Is Free
No worries man.

The reason I was asking was because the study references a range of tens to thousands of ng/g toxins present.

Glycidol exposure within an eight hour period is listed as permissible up to 50ppm but recommended at 25ppm or less. This would be 25000e+9 ng/g or less correct? (I could use clarification of the conversion in all honesty.)

By no means do I then want to quantify VG as safe, but would this seem to indicate that they did not find Glycidol in levels that are considered an immediate problem to exposure?
 

Deleted Member 1643

Well-Known Member
@seaofgreens, also curious about full study, will look into it tomorrow. Formaldehyde level with PEG 400 reported in the abstract is a concern, regardless of one's risk aversion. 230C isn't even that hot.

From the abstract, exposure to the chemicals of concern measured appears to be PEG 400>PG>VG, which corresponds to the perceptions of users. PEG 400 is often described as tasting like plastic, and both PEG 400 and PG can be irritating. IME, concentrate (DIY QWET) requires a minimum of ~10% total PEG 400, with the remainder composed of similar quantities PG and VG. Commercially available products that don't report composition could have much more PEG 400, to be certain any concentrate can be liquefied.

Interesting that MCT was included in the study. Didn't care for vaping MCT.

With dabbing, tolerance is so high that e-juice isn't very appealing. Need to look into a dab-strength portable alternative.

Never found vaping e-juice to be a complete replacement for vaping flower or neat concentrate. That appears to have been for the best.
 
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seaofgreens

My Mind Is Free
Found his old study/topic: http://fuckcombustion.com/threads/ejuice-mixes-vg-pg-safety-journal-article-inside.22290/

So after reading it, I am still curious about the levels found in comparison to what is considered acceptable exposure? So that way, in terms of relative risk, it might be easier to ascertain if you are inhaling minute quantities way below minimal thresholds, or if, as with Acrolein, you are only skirting the edge of safety by a couple hundred mg/g, which seems a bit less comfortable than say, Glycidol, where perhaps you are inhaling a quantity categorically lower than even minimal exposure tolerances?

What are your thoughts on minimal exposure limits anyways while we are at it, but.... no rush to answer if busy though! :p
 

Deleted Member 1643

Well-Known Member
Acceptable daily exposure limits are derived from the no observed adverse effect level, typically in an animal toxicity study, multiplied by additional, often arbitrary, factors in an attempt to account for uncertainties in the study, such as species extrapolation or vulnerable populations, and err on the side of caution.

Inhalation exposure in humans is especially difficult to reproduce in animals, because of differences in physiology. While rats are most commonly used, they are obligate nose-breathers with far more extensive nasal passages than those of humans. This prevents many substances and particulates from ever reaching their lungs, where they could be absorbed and do harm. As a result of this alone, humans are generally more sensitive to inhalation exposure than rats, so a factor of ten is often applied to NOAELs from such studies, but this factor is arbitrary. Inhalation exposure is also generally more sensitive than dietary exposure, because it bypasses liver metabolism.

Ultimately, risk can only be determined from human experience. People have been inhaling these heated glycols and flavorants for about ten years. Also, many users inhaled cigarette smoke for years before switching, which complicates interpretation. Still, a very large number of people have been inhaling PG and VG, which are ubiquitous in e-liquid, during this time with few reported adverse effects. IMO, this is enough to be reasonably confident that the risk posed by occasional use is acceptable. This is just a personal conclusion. It's wide open to debate with little evidence to go on.

PEG 400, on the other hand, is far less common in e-liquid. There's less human experience and therefore, more cause for concern. There's also less experience with flavorants, including terpenes, because while e-liquid is always flavored, the chemicals to which users are exposed varies. For many of these chemicals, no exposure limits have been established.

Still working on getting that article.
 

Deleted Member 1643

Well-Known Member
Apologies for double post - publisher came through with the full article, excerpts below. Great find, @lazylathe!

To generate the samples for carbonyl testing, an Aspire Atlantis 2 tank was filled with the thinning agent being tested and coupled to an Evolv DNA 200 vaporizer controller containing a nickel coil.

Cx7qxCU.gif


PEG 400 produced the greatest levels of formaldehyde and acetaldehyde, followed by PG. VG and MCT produced low levels of formaldehyde and acetaldehyde, including levels that did not reach the limit of quantitation (LOQ) for acetaldehyde (VG only) and formaldehyde (both VG and MCT). None of the thinning agents produced acrolein at levels that reached the LOQ.

Compared with the other agents, PEG 400 produced the largest amounts of acetaldehyde and formaldehyde. The amount of formaldehyde was particularly high, with levels that were nearly four times greater than that produced by PG, more than 226 times higher than that produced by MCT, and almost 242 times greater than that produced by VG. Relative to the other agents, PG produced moderate levels of acetaldehyde and formaldehyde. Both VG and MCT produced low levels of acetaldehyde and formaldehyde. All agents produced low levels of acrolein.

To provide a context for exposure to the carbonyls produced by the four agents, we compared the levels of acetaldehyde and formaldehyde to occupational exposure limits defined by the Occupational Safety and Health Administration (OSHA). Leveraging calculations conducted by Gillman et al., the daily OSHA limits for acetaldehyde and formaldehyde are 2,088,000 and 5300 mg, respectively. Given acetaldehyde’s greater exposure limit, a cannabis user inhaling the byproducts of heated thinning agents would not be exposed to a significant percentage of their daily limit. For example, one inhalation of PEG 400 heated to 230C, which produced the greatest amount of acetaldehyde, exposes an individual to 0.00125% of the daily limit. However, for individuals with a variant ALDH2 gene, any exposure to acetaldehyde may cause adverse effects, including an increased risk of UADT cancers.

Exposure to formaldehyde represents a much greater potential risk. One inhalation of PEG 400 would expose an individual to 1.12% of the daily limit of formaldehyde. Comparatively, smoking one cigarette exposes an individual to 1.42%to 2.35%of the daily limit of formaldehyde. Although not as high as PEG 400, one inhalation of PG exposes an individual to 0.30% of the daily limit. In comparison, one inhalation of MCT or VG would result in an exposure of 0.0050% and 0.0046% of the daily limit, respectively.

Although in practice only a small amount of PEG400 or PG is used to dilute cannabis oil (compared with the isolates used in the present study), these results suggest that consumers potentially expose themselves to health risks when using such products, as formaldehyde inhalation has been linked to increased incidence of myeloid leukemia and nasopharyngeal cancer.

For two reasons, the results may have differed if a cannabis oil-thinning agent mixture were tested. First, the mixture may have produced a different amount of carcinogenic byproducts than the thinning agents alone. A mixture of two components may have boiling and combustion points that are different from either of the components separately. Thus, vaporizing the mixture may increase or decrease carbonyl production. Second, the botanical and chemical compounds found in cannabis oil may affect carbonyl production during vaporization. Cannabis contains hundreds of cannabinoids, terpenoids, and antioxidants that may affect the oxidation of the thinning agents and inhibit or exacerbate the formation of carcinogenic compounds. Unfortunately, due to federal restrictions, in the present study, we were not able to examine carbonyl production in cannabis oil-thinning agent mixtures.

Finally, although acetaldehyde, acrolein, and formaldehyde are the carbonyls that are the most commonly tested for in prior research, thinning agents may produce other potentially harmful compounds. Future work may extend the findings of this study by testing agents for other carbonyls.
 

zomger

Well-Known Member
Shit!:o
Been using an E-cig for about 2 weeks instead of tobacco. Looks like I need to get off of that as well.
Please, whatever you do don't go back to cigarettes! Regardless of whether this article is accurate or not (it's not.) Formaldehyde and Arsenic as well as plenty of other known carcinogen are in those cigarettes,and in much higher levels! This article lost it's credibility in the first paragraph. The PG formaldehyde myth is many years old. Here's an article explaining things. http://lipsiglawyers.com/formaldehyde-e-cig-scare/ You'll notice a theme in articles like OP posted, they jack up the voltage (or in this case temp) to a level no one vapes at and when shit starts burning they point and go "SEE! Dangerous!" The article even admits it saying they cooked the pg/peg at 446 degrees Fahrenheit. I'm using a baby beast right now at 380 degrees. One of many tanks I own, which includes many rebuildables. Never gone over 420 degrees. Didn't matter the material or wrap. Speaking of which we get neither from this article, nor do they tell you the device (some cheap chinese pos i bet.)

Furthermore, while PEG hasn't had the same coverage as PG has in the research department, there were many years you'd find it in a lot of juice. PEG wasn't replaced by PG because they found something harmful about it, in fact, here's a study showing the opposite. http://ejuiceconnoisseur.com/2013/10/21/the-final-word-on-propylene-glycol-vs-polyethylene-glycol/

Look, when it comes to adding chemicals to good ole mary jane, I can definitely see the hesitation from people in this forum. The pay off just isn't worth the risk to most. This is ABSOLUTELY not the case when it comes to e-cigs as an alternate to cigarettes. Here is an article the independent did last summer comparing some of the carcinogen levels in e-cigs to cigarettes. http://www.independent.co.uk/news/s...ful-chemicals-research-suggests-a7159171.html Instead of some bs article pushing propaganda on you this delivers the facts. They don't look amazing at first glance but it's nearly 85% improvement over cigarettes. Then lets try to remember some of the respectable organizations that support e-cig use like the World Health Organization or that the UK Government research showed ecigs to be 95% less harmful than cigarettes.

I hope I've shed some light on this matter for some of you, or if not at least helped you keep a more open mind in the future.
 
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Deleted Member 1643

Well-Known Member
The Project CBD article has it's flaws, but the study on which it's based, excerpted above, seems reasonably sound. The authors probably should have used more than one temp, but this is their reasoning:

The chemical compounds in cannabis, called cannabinoids, vaporize at temperatures ranging from 157 C to 220 C, with combustion beginning at 230 C. Therefore, cannabis oil should be heated to a temperature above 220 C to achieve maximal cannabinoid vaporization but no greater than 230 C to avoid the potential harmful effects of combustion. In the present study, we examined thinning agent aerosols for the presence of carcinogenic compounds when heated at this maximal temperature of cannabis vaporization (230 C).

Their PEG 400 results are eye-opening. As always, they needs to be repeated, but in the mean time, PEG 400 is much less appealing. Just look at that table.

Nope, no more cig's for me, been 2 weeks smoke free now!:tup:

Congratulations! As a cessation aid, e-cigarette use should be temporary, gradually lowering nicotine concentration, until it's no longer desired.
 

Gazaam

Well-Known Member
You need to be very careful when you attempt to "minimize" the importance of these findings. The acceptable safe levels are not determined by long term experiments in humans. Remember that we are dealing here with carcinogens. The way carcinogens produce cancer is that they cause damage to the DNA of a single cell causing a mutation. The changed DNA is therefore no longer the DNA of the body and most mutated cells are easily identified and gobbled up by immune system white cells. HOWEVER there is one type of mutation that activates what is called an oncogene. The prefix onco refers to cancer. Cells with activated oncogene are very primitive, like amoebae and other single celled animals. Oncogenetic cells have mechanisms to insure their survival. They secrete substances that drive the immune cells away so that the oncogenetic cells do not get gobbled up. They also secrete chemicals that stimulate the body to grow more blood vessels into the region of the oncogenetic cells ("neoangiogenesis") . The enriched blood supply allows the oncogenetic cells to multiply much more rapidly, and the cancer is therefore that much more invasive.

So the takeaway here is that it only takes one single oncogenetic cell to start a malignant tumour. Almost all malignant tumours are "monoclonal" meaning that the entire tumour starts from a single cell. It's a numbers game, folks, and therefore there is no "safe" level of any carcinogen. It only takes one carcinogenic molecule to start a cancer. So buyer beware! .
 

C No Ego

Well-Known Member
You need to be very careful when you attempt to "minimize" the importance of these findings. The acceptable safe levels are not determined by long term experiments in humans. Remember that we are dealing here with carcinogens. The way carcinogens produce cancer is that they cause damage to the DNA of a single cell causing a mutation. The changed DNA is therefore no longer the DNA of the body and most mutated cells are easily identified and gobbled up by immune system white cells. HOWEVER there is one type of mutation that activates what is called an oncogene. The prefix onco refers to cancer. Cells with activated oncogene are very primitive, like amoebae and other single celled animals. Oncogenetic cells have mechanisms to insure their survival. They secrete substances that drive the immune cells away so that the oncogenetic cells do not get gobbled up. They also secrete chemicals that stimulate the body to grow more blood vessels into the region of the oncogenetic cells ("neoangiogenesis") . The enriched blood supply allows the oncogenetic cells to multiply much more rapidly, and the cancer is therefore that much more invasive.

So the takeaway here is that it only takes one single oncogenetic cell to start a malignant tumour. Almost all malignant tumours are "monoclonal" meaning that the entire tumour starts from a single cell. It's a numbers game, folks, and therefore there is no "safe" level of any carcinogen. It only takes one carcinogenic molecule to start a cancer. So buyer beware! .

are there cannabinoid receptors on an Oncogenetic cell? since it's such a primitive cell would it use the evolutionary devised lipid signalling system (endocannabinoid system) to maintain itself? interesting, I'll look more into this... here is a youtube of cannabinoids killing cancer cells and a search query link


https://www.youtube.com/results?search_query=cannabinoids+kill+cancer+cells
 
C No Ego,
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Gazaam

Well-Known Member
@ C No Ego: No, I believe most oncogenetic cells are pretty much independent from the body's signalling systems. I would expect that, with a few very rare exceptions (e.g. brain tumour), they do not contain cannabinoid receptors. Here are a couple of other videos that deal with the treatment of cancer with cannabinoids:

https://thegreenrhino.ca/news
 
Gazaam,
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