mg/ml to percent concentration conversion and vice versa

[Mohamed]

This has probably been asked before but I can't find anything what is the conversion for converting mg/ml to a percent concentration. All the FAQ's I've ran across on some ejuice websites just say shift the decimal place for instance 24 mg/ml = 2.4% but this doesn't feel right...been a long time since math class but don't you need to be working with the same units like mg nicotine divided by mg of total weight.

Wouldn't you have to figure out what 1 ml of ejuice (flavors + pg + vg + nic) weighs and isn't that going to vary between vendors and flavors based on the ingredients used? Maybe this number is magically so close for all ejuice and the math works out easier if they just say move the decimal place over and the true number is insignificant or so close to the divide by 10 method that no one cares?

I'm just curious...I am used to buying in mg/ml but Johnson Creek only offers in concentration which lead me on this wild goose chase for a conversion. Also the ejuice I'm looking at says "High Quality, PG-based Smoke juice" what does that mean for PG and VG ratio. I'm used to 50/50 for that and you can't select that on their website either. I normally wouldn't go through all this work trying to figure all this out and would just go on to next website but tried a friends chocolate truffle that he got from there and liked it enough to want a bottle of my own.

 

[degnr8]

Shift the decimal is right. 10mg=1%

 

[Ryedan]

There are 1,000 mg of water in 1,000 ml of water.

So,
1,000 mg = 100%
100 mg = 10%
10 mg = 1%

So, it is correct that moving one decimal place will convert these units.

ETA: Damn, you beat me to it by 1 minute degnr8!

 

[LucentShadow]

I'm no chemist, but I found a source stating that the density of nicotine is 1.01g/cm^3. That would seem to equate to 1,010mg/ml, if I'm correct.

That's close enough to 1000mg/ml to do a simple decimal place shift to correlate it to 100%, and still be very close to correct.

 

[Mohamed]

There are 1,000 mg of water in 1,000 ml of water.

Not sure your math applies when your not dealing with water. This is more like oil.

 

[Mohamed]

I'm no chemist, but I found a source stating that the density of nicotine is 1.01g/cm^3. That would seem to equate to 1,010mg/ml, if I'm correct.

That's close enough to 1000mg/ml to do a simple decimal place shift to correlate it to 100%, and still be very close to correct.

Ahh density...forgot about that guy. Ok so I no longer have to worry about the weight of the ejuice.

So the 2.4% stuff would be 1010*0.024 would really be 24.24mg/ml slightly higher than the move decimal place rule
and 24mg = 24/1010 * 100% = 2.376 % slightly less than the move decimal place rule

Yeah close enough that I'm not going to notice the difference.

Now that I got that cleared up and satisfied my curiosity. For Johnson Creak what does the "High Quality, PG-based Smoke Juice" mean. 100% PG and 0 VG. Or would I be better off just contacting them directly on that question.

 

[LucentShadow]

Here's an old post from a chemist on this forum. It's interesting, and pertinent to this topic.

http://www.e-cigarette-forum.com/fo...nsity-liquids-possible-volume-contration.html

ETA- Yeah, PG-based should be just nicotine and PG.

 

[Mohamed]

Here's an old post from a chemist on this forum. It's interesting, and pertinent to this topic.

http://www.e-cigarette-forum.com/fo...nsity-liquids-possible-volume-contration.html

ETA- Yeah, PG-based should be just nicotine and PG.

He's using 1.009 g/mL or 1009mg/ml instead of 1010mg/ml but still close enough that it's not going to alter the numbers too much.

That thread is a bit over my head with hydrogen bonds and contraction etc. I suppose you really only need to know the formula or whatever they are talking about in that thread is if you make your own or are a distributor. I kind of doubt most people that make their own are chemists. I don't plan on making my own any time soon but if I do go that route I'll be sure to research it a bit more.

The unknown vendor he was talking about had a 40mg/ml marked as 36mg/ml that's an 11% margin of error...seems a bit high to me of course that was 2 years ago and good to see that vendor was at least having his stuff tested to see what it came back as. Bit off topic but makes me wonder when I buy the cheap stuff vs the moderate priced stuff as to what I'm actually getting.

I'm not very found of government intrusion but it would be nice to see these vendors do periodic tests and post those results on their website. I'd be much more likely to purchase and even pay a slightly higher price if I knew there margin of error was +- 0.5% or less. At least then I'd have confidence that they knew what they were doing. No idea what the acceptable margin of error is for other industries but at least they would be preparing themselves for inevitable regulations that are likely to come at some point. Besides that they would also be defusing some the news that say the consumer doesn't know for sure what they are getting.

 

[LucentShadow]

Yeah, a bit over my head, too. Seems there can be some issues with mixed liquid's volume not totaling the sum of their parts, thus changing the concentration unexpectedly. But being aware of that possibility makes it fairly easy to spot, if you double-check the finished volume.

There was a big fiasco with a certain vendor selling e-liquids that were way off their marked nic concentration back around that time, or a bit earlier. I believe Kurt was the one that confirmed the problem, and has been working with several vendors in some capacity since then to get their quality control up. I don't remember if there was ever any explanation of what caused the problem, but I'd have to guess that it was pure procedural error, as the error was huge.

I'm pretty sure that awareness of that issue is high with the vendors that were around at that time. Hopefully newer ones don't repeat it.

 

[Iffy]

If anyone can DIY nic mix to within .1% (1000 vs. 1009)...

 

[Mike Sheda]

And I thought bytes to the megabyte was hard math!

 

[Jsucool76]

I used to always think that, for instance, 24mg was 2.4% nicotine, but I know whitecloud (the place where I got my first kit from) sells cartomizers (prefilled) which they describe as 5.4% nicotine...by that math it would be 54mg...seems a little high

 

[LucentShadow]

I used to always think that, for instance, 24mg was 2.4% nicotine, but I know whitecloud (the place where I got my first kit from) sells cartomizers (prefilled) which they describe as 5.4% nicotine...by that math it would be 54mg...seems a little high

That's pretty much 54mg/ml. That's terrible, though it seems they still sell that, after looking them up. I've heard of some others that sell up around that high in prefilled cartos, too, or maybe it was them...

I could not point a newbie to that site with anything but evil intent. Bah.

 

[degnr8]

That's pretty much 54mg/ml. That's terrible, though it seems they still sell that, after looking them up. I've heard of some others that sell up around that high in prefilled cartos, too, or maybe it was them...

I could not point a newbie to that site with anything but evil intent. Bah.

Why? When I started vaping it was 50mg DIY. That was the strength I needed to beat a 2 1/2 PAD non-filters habit.

 

[Ryedan]

And I thought bytes to the megabyte was hard math!

I like to think of that as kinda like plus or minus a two four

 

[LucentShadow]

Why? When I started vaping it was 50mg DIY. That was the strength I needed to beat a 2 1/2 PAD non-filters habit.

Hmm. I should have figured that someone would openly take exception to my opinion. So... I feel that way for several reasons.

On their Learn -> Guides & Instructions -> How To Choose Your Nicotine Strength menu (Sorry, I won't link to them, since they are not approved of by ECF, or myself,) where they outline their options, they state that each of their 'cartridges' are generally equivalent to about two packs of cigarettes, and that if you find yourself exhausting them more often than that estimate, you may need to choose a higher strength cartridge.

First, an obviously dishonest statement that I believe most here would disdain. I'm pretty sure that most people here would not equate a single pre-filled carto to two packs of smokes, no matter the strength. Many here would blow through that in a couple of hours, easily. Then, they suggest that if that very typical reality rears it's head, you should probably get a higher strength.

My observation about most vapers is that they tend to want lots of vapor with each hit, and also tend to vape rather more often than they smoked. This, in my opinion, does not mix well with their offerings of extremely high strength and misinformation.

I've run across the odd person here that touts that as a good thing, so perhaps it's good that these places are out there, for them. I've only seen a few here that prefer very short, infrequent, extremely harsh hits when vaping, so I think that their spinning their product in a dishonest light could easily lead new users to use more nicotine than they really need to.

Not a good thing, IMO, as I've seen some of the effects on people who severely overdo nicotine or caffeine. I'd prefer to see WTA on offer for the hard-cases, as it's been observed to be quite effective at much lower doses of nicotine.

 

[H. Hodges]

That's pretty much 54mg/ml. That's terrible, though it seems they still sell that, after looking them up. I've heard of some others that sell up around that high in prefilled cartos, too, or maybe it was them...

I could not point a newbie to that site with anything but evil intent. Bah.

With the low quality of the prefilled carto devices, it takes that high of a content to deliver enough nic to be even somewhat effective! But if your soul desire is to frustrate the bejesus out of someone (deserving or not), then yea, point them in that direction. However, I don't believe the nic content is/would be a factor since the delivery system can't get it into them!

 

[degnr8]

On their Learn -> Guides & Instructions -> How To Choose Your Nicotine Strength menu (Sorry, I won't link to them, since they are not approved of by ECF, or myself,) where they outline their options, they state that each of their 'cartridges' are generally equivalent to about two packs of cigarettes, and that if you find yourself exhausting them more often than that estimate, you may need to choose a higher strength cartridge.

First, an obviously dishonest statement that I believe most here would disdain. I'm pretty sure that most people here would not equate a single pre-filled carto to two packs of smokes, no matter the strength. Many here would blow through that in a couple of hours, easily. Then, they suggest that if that very typical reality rears it's head, you should probably get a higher strength.

so I think that their spinning their product in a dishonest light could easily lead new users to use more nicotine than they really need to.

Not a good thing, IMO, as I've seen some of the effects on people who severely overdo nicotine or caffeine. I'd prefer to see WTA on offer for the hard-cases, as it's been observed to be quite effective at much lower doses of nicotine.

I'd have to agree with you. It seems that that type of info would get everybody using the 54mg. Whether the WTAs would have been more effective, I don't know. Didn't know about them at the time.

 

[LucentShadow]

I'd have to agree with you. It seems that that type of info would get everybody using the 54mg. Whether the WTAs would have been more effective, I don't know. Didn't know about them at the time.

I'm not thinking everyone would overdo it, but possibly quite a few could be steered that way. I'm really tired of the overblown claims, especially.

Anyway, I do hope that WTA e-liquid continues to gain traction. I have not tried it yet, but will be, sometime soon. I have yet to quit smoking. I've cut my cig consumption considerably, but even high-strength nic liquids do not reduce my cig cravings much, and anything 24mg/ml or above are too harsh on my throat and lungs.

The research that I've done on it so far indicates that it usually works for people like me, and often at surprisingly low levels. Further study is warranted on it's risk level, compared to isolated nic, though it's generally considered potentially slightly higher risk for TSNAs, as far as I can tell. Still has to be much better than cigs.

I'll end the off-topic tangent here with a link to DVap's blog, in case anyone reading this is interested:

E-Cigarette Forum - DVap - Blogs

Seems he is the main pioneer of WTA. Aroma-EJuice and WholeCig are the two place that I've found that sell it.

 

[darkstorm]

That is exceptionally high but not surprising. Njoy Kings are 3.6% 36mg/ml. I guess if you are a two pack a day smoker that might be appropriate but if I was to vape that (currently constantly vaping 6mg/ml) it would make me sick.