E-Liquids: Milliliters, Milligrams and mg/ml
If you’ve ever browsed a vape shop abroad, you’ll have noticed that ready-mixed e-liquids often list values in mg/ml. It’s important to understand that a milligram is not the same as a milliliter – so how should you read these figures? And what does that mean if you mix your own e-liquid?
Under specific air pressure and temperature conditions, 1 ml of water does indeed weigh 1 mg – but we’re talking about lab conditions here, with an air pressure of 101.325 kPa and exactly 3.98 degrees! Since e-liquids obviously aren’t just water, but contain ingredients such as PG (propylene glycol), and PG is naturally heavier than water, the total amount of e-liquid isn’t stated in grams. That’s why e-liquid volume is given in milliliters, not milligrams.
On e-liquids abroad, milligrams always refer to nicotine. Cigarette packs also list nicotine in mg. However, 0.5 mg of nicotine on a pack of light cigarettes doesn’t mean “you absorb 0.5 mg of nicotine while smoking”. It means that, under lab conditions, a machine can extract 0.5 mg of nicotine from that cigarette. As a smoker, you can’t do that, because you’d have to draw on the cigarette non-stop for a full two minutes and inhale the smoke deep into your lungs the whole time – in reality, for technical reasons, you’d simply suffocate. On top of that, your body can’t absorb the full 0.5 mg anyway.
When DIY mixers abroad add nicotine, the nicotine is in liquid form – and again, it’s labeled in mg/ml. From this, you can calculate a simple volume percentage: for example, how many ml of that nicotine liquid to add to 100 ml of e-liquid to achieve the nicotine strength you want to vape. Professionals who sell nicotine mixes abroad, for example, verify the nicotine content. But any vaper can also check the nicotine level in their own e-liquid using simple, legal supplies from a pharmacy.
We’ll explain what you need for that in our next blog post! Swiss residents may import 150 ml of e-liquid containing nicotine per postal shipment for personal use (see the Swiss Federal Customs Administration leaflet) and are, of course, also allowed to check the nicotine content themselves.
