# Trace metals: A comparative study between Ecigs aerosol and cigarette smoke



## stevie g (28/1/17)

Home Science  Trace metals: A comparative study between Ecigs aerosol and cigarette smoke






SCIENCE
*Trace metals: A comparative study between Ecigs aerosol and cigarette smoke*
A study shows that metal concentrations in e-vapor are one order of magnitude lower than in smoke. This result is highly dependent on the couple e-liquid/hardware tested. Here, nickel is present in the aerosol generated by the e-cigarette. Its origin is the heating element but its toxicity to the organism is dampened because of a quasi absence carbon monoxide.

By
Jérôme Harlay
-
January 27, 2017
288
1

http://www.facebook.com/sharer.php?...dy-between-ecigs-aerosol-and-cigarette-smoke/
https://twitter.com/intent/tweet?te...-aerosol-and-cigarette-smoke/&via=vaping_post
http://plus.google.com/share?url=ht...dy-between-ecigs-aerosol-and-cigarette-smoke/
http://pinterest.com/pin/create/but...-content/uploads/2017/01/smoke-69124_1280.jpg
http://www.ecigssa.co.za/whatsapp:/...dy-between-ecigs-aerosol-and-cigarette-smoke/

*Metal concentration in e-vapor is comparable to atmospheric air, except for Ni*
Researchers at Lincoln Memorial University (Harrogate, TN, USA) and at William Carey University (Hattiesburg, MS, USA) carried out a comparative analysis of *trace metals in e-cigarette aerosol and cigarette smoke*.

The contents of Al (aluminium), As (arsenic), Cd (cadmium), Cu (copper), Fe (iron), Mn (manganese), Ni (nickel), Pb (lead), and Zn (zinc) were determined from both sources, in the e-liquid
Filling solution for e-cigarettes.

An e-liquid is a solution that produces steam when heated.
" class="glossaryLink " style="box-sizing: border-box; color: rgb(34, 34, 34); border-bottom: 1px dotted rgb(0, 0, 0) !important;">e-liquid and tobacco. The authors also conducted a conspicuous elemental analysis of all the parts of the cartomizers and analysed carbon monoxide (CO) emitted from the electronic and combustible cigarettes. Finally, the matter deposited on membrane filters exposed to smoke or aerosol was submitted to elemental analysis of C (carbone), O (oxygen) and N (nitrogen).

*Analysis of Trace Metals*



Accumulation of trace metals on MCE membranes exposed to e-cigarette-generated aerosol.
The major finding of this study is that *none of the analyzed trace metals on aerosol-exposed membrane filters were significantly different from control filters, except Ni*, which was nearly five times higher than on control filters.

*Toxicity: Is Ni a source of concern?*
The authors show that, *except for Ni*, the trace metals found in e-vapor were at *levels comparable with ambient air* and in much lesser concentration than in the smoke of Marlboro cigarettes. Except for Ni, it is unlikely that the aerosol produced by e-cigarettes contains enough of the other trace metals to induce significant pathology. However, we will see later that it is *not to be considered as a general ruling*.

Ni is first responsible for* allergies*. Ni can be found in many everyday items, such as coins, belt buckles, zippers, eyeglass frames, and causes an itchy rash where the skin is in contact with the metal. It is what you have to be careful with, when using an e-cigarette because a similar allergic reaction can also be expected in the respiratory tract, especially if you ever had a skin reaction in the past.

It is explained by the authors that the *potential carcinogenicity* of Ni is related to its ability to form *nickel carbonyl (Ni(CO)4)* with excess of CO. Hence, the toxicity of Ni is higher for combustible products and in case of dual use than for e-cigarettes only. This is confirmed by their analysis of CO that showed 831 ± 166 μM/L in smoke while its value in e-vapor was lower than 0.010 ± 0.003 μM/L, close to air samples. It must be noticed that Ni was undetectable in Marlboro smoke during this study.

*A device-related issue*


In their discussion, the researchers point out the fact that the presence of trace metals in e-vapor is strongly related to the device that is tested. Here, the e-cigarette was a Triple3 eGo that was used with a e-liquid tobacco flavor, very high nicotine (7 s Electronic Cigarette company, South Lake, TX).

Triple3 eGo E-cigarette:
The atomizing chamber and the cartridge are combined into a single unit, the clearomizer, a plastic tank of 1.6 ml e-liquid capacity. The device also includes a 650 mAh lithium ion battery (3.7 V, unregulated), a silicon ring at the base of the drip-tip
Part of the e-cigarette through which the vaper inhales e-vapor. It is also called _mouth piece_ since it is the part that is in contact with lips.

The drip-tip can be removed in some cases. They are generally made in plastic but one can also find metallic ones. They are also fashioned by designers to bring originality.
" class="glossaryLink " style="box-sizing: border-box; color: rgb(34, 34, 34); border-bottom: 1px dotted rgb(0, 0, 0) !important;">drip-tip. The resistance coils varies between 2.2 and 2.6 Ω for an average power output of ~5.7 W.

7 s Electronic Cigarette company Juice:

80% propylene glycol and 20% vegetable glycerin, 24 mg/ml of nicotine or ~3.4 mg nicotine/15 puffs. A trace of flavoring is added to the blend to provide the tobacco taste.Technical features of the e-cigarette and the e-liquid used in the test

Scanning electron microscopy (SEM) coupled to energy-dispersive X-ray spectrometery (EDS) allowed the scientists to determine with precision *the composition of each part of the cartomizer* after careful dissection. They identified the Ni-rich parts that were in contact with the e-liquid and that could have been a source for this metal. Analysis of the e-liquid before filling the tank revealed that no trace metal was present at detectable levels.

Their results indicate that most of the Ni was concentrated at the level of the core, the coil, the thick wire and the weld joint of the core assembly. Hence, *the heating element of the eGo* was very likely the source of Ni to the aerosol.




Elemental analysis of the core assembly using EDS
The authors demonstrate, here, that the issue it not the quality of the e-liquid but rather the hardware itself, and especially its resistance coil. In other studies, aerosols of four different brands of cartridge type e-cigarettes showed that Sn, Cu and Zn, in addition to Ni could also be emitted in the aerosol. In this case, the source of trace metal contamination was found to be the metallic parts in contact with the e-liquid stored in the cartridge. The transfer from the solid phase to the e-liquid may depend on several factors among which the corrosiveness of the e-liquid, its pH and the presence of organic acceptors like proteins, for example.

*Other interesting findings*
*Volume of e-liquid vaporized per 5 s puff*
The volume of e-liquid vaporized _per_ 5 s puff was calculated by the authors and averaged 9.3 μl in this study (7 s e-liquid/eGo). Such a value is specific to the cartomizer used in the experimental design and may be used for the comparison with other datasets and the interconversion between puffs and volume.

*Visual inspection of filters*
The authors demonstrate the performance of the experimental design to trap particle with the visual inspection of filters.




Visual inspection of membrane filter surfaces
A blank membrane filter is white. The pinkish appearance of the filters exposed to e-vapor is uniform and consistent with the brownish color of the 7 s e-liquid. In contrast, smoke stains the membranes with a color gradient ranging from light beige to dark brown, with increasing puff number.

*Fundamental differences between vapor and smoke*
The authors show fundamental differences between the physical natures of the aerosol (made up of liquid droplets) and the smoke (which is made up mostly of gas and particulate matter).This difference lead to a lower percent recovery of aerosol on membranes filters than percent recovery of smoke.

Another difference concerns the temperature: The aerosol was warmer than smoke although smoke is generated at higher temperature (800°C) than vapor (350°C).

*Estimated smoke and aerosol trace metal content per 20 pack equivalent*



Estimated contents (μg) of Al, As, Cd, Cu, Fe, Mn, Ni, Pb, and Zn from the vaporization of E-liquid equivalent to 20 cigarettes or from the combustion of 20 Marlboro cigarettes
More interestingly, the researchers determined estimated contents of trace metals from the vaporization of e-liquid equivalent to 20 cigarettes or from the combustion of 20 Marlboro cigarettes. The comparison with recommended exposure limits (REL) published by the National Institute for Occupational Safety and Health (NIOSH) and the permissible exposure limits (PEL) published by the Occupational Safety and Health Administration (OSHA) is tricky because, conceptually, the use of those products is first recreational and, second, intermittent which contrasts to occupational exposure in workspaces. This has been discussed in length by K. Farsalinos.

*In conclusion*
A simple and effective experimental design has been imagined to collect and trap aerosol as smoke. Various designs exist, used by other research teams and ranging from the simplest syringe-pumping protocol to the most advances vaping/smoking machines that can reproduce different vaping or smoking topographies. In this debate, the authors point out the need for standardizing the experimental approach so that experiments may be reproduced with the same settings and results compared.

Filters were exposed to aerosol or smoke during up to 45 cycles of a 5 s puff (pump active) followed by a 10 s rest period (pump inactive). A combustible cigarette is equivalent to 15 puffs. The authors chose longer puff duration to balance for lower flow rate used to preserve the integrity of fragile MCE membrane filters.Topography settings and justification:
The researchers recommend to manufacturers to minimize the use of excessive Ni in devices. But at the user’s level, the first recommendation is to avoid using NiChrome or Ni200 resistance coils in electronic reconstructible mods.

They notice that with temperature controlled devices, Ni toxicity becomes even more critical because most of these last-generation devices use coils made of quasi pure Ni. Ni-Chrome (alloy of 80% Ni and 20% Cr) is another popular material that should be avoided because it contains high concentration of Ni. In contrast, Kanthal (alloy of Fe, Cr and Al) represents the opposite extreme since it doesn’t contain Ni. But the latter also cannot be used in TC mode because its resistance doesn’t change with the electric current and cannot be used to predict coil temperature.

_Palazzolo, D. L., Crow, A. P., Nelson, J. M., & Johnson, R. A. (2016). Trace metals derived from electronic cigarette (ECIG) generated aerosol: potential problem of ECIG devices that contain nickel. Frontiers in Physiology, 7, 663._

Image credit: Pixabay CC0


TAGS
7 S E-LIQUID
AEROSOL
ANDREW CROW
DOMINIC PALAZZOLO
E-LIQUID
E-VAPOR
EGO
JOHN NELSON
KANTHAL
NI
NI200
NICHROME
NICKEL
ROBERT JOHNSON
TRACE METALS
http://www.facebook.com/sharer.php?...dy-between-ecigs-aerosol-and-cigarette-smoke/
https://twitter.com/intent/tweet?te...-aerosol-and-cigarette-smoke/&via=vaping_post
http://plus.google.com/share?url=ht...dy-between-ecigs-aerosol-and-cigarette-smoke/
http://pinterest.com/pin/create/but...-content/uploads/2017/01/smoke-69124_1280.jpg
http://www.ecigssa.co.za/whatsapp:/...dy-between-ecigs-aerosol-and-cigarette-smoke/

Previous articleWelsh hostility to vaping continues, but FDA backs off another step




Jérôme Harlay
PhD in science and journalist for the Vaping Post. Specialised in scientific topics.


*RELATED ARTICLESMORE FROM AUTHOR*



Press
*Welsh hostility to vaping continues, but FDA backs off another step*



America
*FDA releases a guidance document relevant to free samples*



Review
*Osub Mini Kit – Smok*


- Sponsors -



*Le Petit Vapoteur*
The famous french online store is now open to international customers. Hundreds of e-liquids and material available.




*Rude Oil e-liquids*
The best fuel for your tank. A hot new range of flavours to make your mod rock. Soon to be available at pumps across the world.




*Smokjoy*
Demon Hunter RDTA Air 50S Micro Kit First Debut. Click logo on left to see more.




*Advertise here*
Associate your brand with serious and highly targeted content.







*Latest news*




Science
*Trace metals: A comparative study between Ecigs aerosol and cigarette smoke*
Jérôme Harlay - January 27, 2017
1
Metal concentration in e-vapor is comparable to atmospheric air, except for Ni Researchers at Lincoln Memorial University (Harrogate, TN, USA) and at William Carey University...



*Welsh hostility to vaping continues, but FDA backs off another step*
January 27, 2017



*iCare – Eleaf*



*FDA releases a guidance document relevant to free samples*
January 26, 2017



*Osub Mini Kit – Smok*





Vaping Post is your international vaping news, articles and reviews website. We provide you with the latest breaking news and information straight from the vaping world.
    
*EVEN MORE NEWS*



*Trace metals: A comparative study between Ecigs aerosol and cigarette smoke*
January 27, 2017



*Welsh hostility to vaping continues, but FDA backs off another step*
January 27, 2017



*iCare – Eleaf*
*POPULAR CATEGORY*

Politics212
Science129
Business120
Europe99
Community97
Review78
Society72

Disclaimer
Privacy
Advertisement
Contact Us
Vaping Events calendar
Newsletter
Glossary
© Copyright 2017 - Vaping Post

Reactions: Like 1 | Winner 3 | Informative 4


----------



## Silver (28/1/17)

Thanks for sharing this @Sprint 
I haven't gone through the entire article carefully yet - but I did read the conclusion and looked at some of the tables.

Do you think this means we should steer away from NI80 wire? 
And stick to Kanthal?

Reactions: Agree 1


----------



## craigb (28/1/17)

That's pretty much what they suggest.


Silver said:


> Do you think this means we should steer away from NI80 wire?
> And stick to Kanthal?


----------



## Clouds4Days (28/1/17)

In the conclusion nothing was mentioned about ss unless i missed it?

Reactions: Agree 1


----------



## stevie g (28/1/17)

SS is probably safer.

Chromium hexavalent is a concern but only at molten temperatures.

So don't dry burn past dull red. And always rinse the coil.

Reactions: Agree 1 | Thanks 1 | Informative 1


----------



## Clouds4Days (28/1/17)

Sprint said:


> SS is probably safer.
> 
> Chromium hexavalent is a concern but only at molten temperatures.
> 
> So don't dry burn past dull red. And always rinse the coil.



Awesome , thats something i learned on ecigssa too.
I never used to rinse (cool) my coils in water while dry burning.

But now i do and the wire looks brand new if you do that.

Reactions: Agree 1


----------



## gertvanjoe (29/1/17)

That article talks about 2.6 ohm coils. Nice and interesting find, but who uses that ?

Reactions: Like 1


----------



## Silver (29/1/17)

gertvanjoe said:


> That article talks about 2.6 ohm coils. Nice and interesting find, but who uses that ?



I still use 1.8 ohm coils on my Evod1 @gertvanjoe - but granted only in the morning and for stealth purposes.

It worries me that these findings would potentially be further amplified at lower resistances and much higher power.

Am looking at some of my NI80 coiled devices and thinking to perhaps recoil them with Kanthal or give SS another try.


----------



## gertvanjoe (31/1/17)

Silver said:


> I still use 1.8 ohm coils on my Evod1 @gertvanjoe - but granted only in the morning and for stealth purposes.
> 
> It worries me that these findings would potentially be further amplified at lower resistances and much higher power.
> 
> Am looking at some of my NI80 coiled devices and thinking to perhaps recoil them with Kanthal or give SS another try.



I'm a happy camper at normal kanthal. Kanthal in itself is probably already a weird concoction, but I'll steer clear of all the other

Reactions: Like 1


----------



## Cespian (31/1/17)

Man - N80 is my favourite

Reactions: Agree 2


----------

