E Liquid Testing Policies & Procedures


ECTA E-Liquid Testing Standards

### Last Updated – Feb 1st, 2017

Summary of Modifications – We have updated our member testing requirements to help ease the cost burden on non-manufacturing retail members while still maintaining a level of accountability.  As well, we have increased the requirements of the Manufacturer to include flavourant testing as it is our belief that testing should ultimately be the responsibility of those manufacturers.  We have also added percentages of PG and VG to our testing protocol.

ECTA recognizes the need for standards and appropriate testing for E-Liquid. We continually investigate different processes for testing to ensure our protocols identify potential risks and issues with E-Liquid ingredients. Our process is continuously revisited, improved and adjusted as needed or dictated by the science and challenges within the industry. Below are the standards we apply to our members. We also encourage any E-Liquid manufacturer, reseller or even private DIY’er to follow the same.

NOTE: These guidelines do not reflect the entire official standard or a policy document of ECTA. They are provided as information on our current processes. Also, these standards do not reflect a stance of “these standards make E-Liquid safe”. Electronic Cigarettes are not safe in absolute terms, (nor would that be possible) with these standards, or any other known standard. Our goal by using this standard of testing is for them to be “safer” and to continue to become safer for everyone as the industry moves forward.

The Rules of ECTA Testing:

This is a summary of the guidelines applicable to all ECTA members for testing, including how and when samples are selected for testing.

  • ECTA performs member audits every six (6) months.
  • Mandatory audit participation begin after a member has been with ECTA for at least six (6) months. This period of time is used by new members to ensure they are following all applicable guidelines for quality control in manufacture and retail of E-Liquid.
  • Members may participate at their discretion prior to their six (6) month membership date as this initiates their audit history.
  • Along with E-liquid testing, all labels are also inspected for each bottle size that the member sells to ensure that they meet ECTA and CCCR 2001 label standards (click for details).
  • Members may send samples for testing at any time prior to the audit cycle and submit those results to our auditor for audit fulfillment.
  • Members may submit/send more than the minimum number of samples required.
  • If a member sells an E-liquid that is manufactured by an ECTA member, they are exempt from submitting samples from that manufacturer because they are already being tested and audited by that member. The member may however, submit random samples of E-liquid from a manufacturer who is an ECTA member for their own audit record and internal QC processes.
  • Each member is responsible for any costs associated with testing of their samples.
  • The items that must be submitted depends on the type of business they operate (see Retail / Wholesale Distributor and Manufacturer sections below)

Retail / Wholesale Distributor

  • Within one (1) year or two (2) audit cycles, one (1) sample from each line of E-Liquid that is sold must be tested.
  • This requirement for testing can be fulfilled by any combination of:
    • Member submitted samples through the ECTA Auditor for testing
    • Test results provided by the manufacturer that at least include both Diacetyl (2,3-Butanedione) and Acetyl Propionyl (2,3-Pentanedione) with a Method Detection Limit (MDL) equal to or less than the disclosure limit for that compound.  Testing results MUST be less than 12 months old.


Submission process: test samples are recorded, marked and forwarded to a Central Collection Point which is the ECTA third-party auditor. The auditor records and inspects the collected samples and forwards them to the Lab for testing.

ECTA uses Enthalpy Analytical Inc, located in Durham, NC (USA) for our E-Liquid testing for several reasons:

  • Complies with Health Canada testing methods (ISO 17025)
  • Work with AEMSA so they are familiar with our needs
  • Work closely with Dr. Konstantinos Farsalinos, M.D. on E-Cigarette Research
  • Perform specific Electronic Cigarette research and lab studies for researchers internationally.

Specific Testing Points, Protocols and Tolerance:

Our testing protocol includes testing for the following items:

Component / Element Protocol
Nicotine Concentration GC/FID Analysis
0.1 mg/ml
± 10%
Diethylene glycol (DG) GC/FID Analysis
2.23 µg/ml (ppm)
< 100 µg/ml (ppm)
Acetaldehyde HPLC/UV Analysis
0.640 µg/ml (ppm)
< 100 µg/ml (ppm)
Acetoin HPLC/UV Analysis
0.841 µg/ml (ppm)
None Set (Informational)
HPLC/UV Analysis
0.742 µg/ml (ppm)
Non-Detection Goal
< 22 µg/ml no disclosure
< 100 µg/ml (ppm) disclosure
> 100 µg/ml (ppm) is Fail
Formaldehyde HPLC/UV Analysis
0.846 µg/ml (ppm)
< 30 µg/mL (ppm)
Acetyl Propionyl
HPLC/UV Analysis
0.840 µg/ml (ppm)
Non-Detection Goal
< 45 µg/ml no disclosure
< 100 µg/ml (ppm) disclosure
> 100 µg/ml (ppm) is Fail
pH Level Karl Fischer Analysis Target Levels (Informational)
5.0 to 8.5
% Water Karl Fischer Analysis None Set (Informational)
% Propylene glycol (PG) ± 10%
% Vegetable glycerin (VG) ± 10%

* MDL – Method Detection Limit or Level of Detection (LOD). The MDL remains constant with some variation from test to test depending on the calibration of equipment.

The MDL is one of the most critically important aspects of E-Liquid Testing. By way of example: Diacetyl (2,3-Butanedione) and Acetyl Propionyl (2,3-Pentanedione) are common compounds in flavoring that contain certain ketones linked, though not conclusively, to a serious disease “Bronchial Obliterans”, commonly called “Popcorn Lung”. As a minor constituent in flavoring, often undeclared by flavorants manufacturers, it is generally found in very small amounts. Therefore, the most sensitive detection limit is required to either find or rule-out Diacetyl in any commercially marketed eliquid.

The Occupational Safety and Health Administration (OSHA) has not set any “safe exposure limits” for Diacetyl, and permit it’s use in trace quantities in food flavoring. Scientific research is not conclusive, at this time, on whether there are safe limits for inhalation of this chemical (though it is found in larger quantities in tobacco cigarettes, which have not been indicated in or linked to Bronchial Obliterans at this time.

We position Electronic Cigarettes as a Tobacco Harm Reduction tool, so our goal should be to eliminate as many harmful aspects as possible. Tobacco Cigarettes contain Diacetyl in concentrations of 250+ ppm. Therefore, whatever testing protocol is used should be expected to test to well below that level.

GC/MS testing is probably one of the most common and least expensive true tests that can be performed, BUT the key to suitable testing and proper detection is the MDL (or LOD) for the test. Many of the GC/MS testing reports that we have seen indicate a detection limit of 0.1%. That is 1000 µg/ml or ppm which is not suitable to show any substantial evidence of safety level.

That’s not to say that GC/MS is not suitable but that if you are using GC/MS testing, be certain to check and understand the lower detection limit for what you are attempting to detect.

Test Results:

The Test Result Reports are anywhere from 20-40 pages in length and are extremely complex and detailed. Reading and understanding the results does require training and qualifications in this area. ECTA’s Board has engaged in long and detailed conversations with Enthalpy about the results, and we appreciate the skill required to understand and read tests correctly, but do not position ourselves as qualified to do so.

Results are returned to the member, with a copy forwarded to an qualified, independent third party for audit and historical purposes. The third party auditor reviews the results, deems pass or fail for each sample and follows-up on actions taken for any issues that may have been identified in the results.

Tests are paid for by the member, the results are the property of that member and they may disclose those results, in whole or part, to the public, at their own discretion. While this policy may change at some point in the future, that is the policy as of now.

Example Report / Actions Required:

Result Snippet

Click the document link on the left to see a sample of what an ECTA test result from Enthalpy looks like (Note: It is 4.6 MB in size).

The screen shot below demonstrates 3 samples “passed” by ECTA standards (refer to thresholds above), though with registered traces of Acetyl Propionyl and/or Diacetyl as seen on the Carbonyls Summary (Page 6). These thresholds are currently monitored with the following protocol:

Result Snippet

The ECTA standard is a non-detection for these elements. However, there are a couple of threshold levels for both Acetyl Propionyl and Diacetyl into which a result may fall.

  • Non-Detection of Pentanedione and Diacetyl – This is the ECTA standard to which all members must strive to achieve
  • < 22 µg/ml for Diacetyl and < 45 µg/ml for Acetyl Propionyl no disclosure – This is a “caution” threshold, though while recommended, is not required for disclosure. Members are required to work towards removing the cause of the compound. Levels in this range are most often attributed to cross-contamination.
  • < 100 µg/ml disclosure – This “caution” threshold requires disclosure to consumers if the eliquid remains on the market, and a plan to replace the flavorant with an alternative. Disclosure is required on a website (if applicable), in a Retail Location (if applicable), and optionally on the label of the product (pending stock level depletion)
  • > 100 µg/ml (ppm) indicates a “FAIL” – This is above the upper limit and beyond ECTA standards. If an E-Liquid result shows higher than this level the member must immediately stop sale of that product and either discontinue or return the product to their shelves only after the E-Liquid is reformulated and re-tested to show that it has been corrected.

Lower caution thresholds registered in the above graphic are given a temporary “pass” with prescribed action required to identify the origin and remove or correct the problem.

ECTA recognizes that flavorant manufacturing companies are not connected to, nor specifically formulating for the E-Liquid industry. The occurrence of Diacetyl and other compounds are viewed differently by this industry for use in foods and beverages. Due to the manufacturing practises of the flavorant industry, it may require additional time to identify potentially harmful compounds, find alternatives and suitable flavorings for inhalation. Testing is a critical component to ensuring we support a process of increasing safety and timely responses to current and future issues. That is the backbone of “harm reduction”.

If you have any questions regarding E-Liquid testing, please do not hesitate to Contact Us