Machine Vaping of Electronic Cigarettes - A Comparison of Puffing Regimes#

Gupta, Amit; Tayyarah, Rana; Gillman, Gene; Garner, Charles; Stevens, Rob

doi:10.2478/cttr-2021-0009

Figures & Tables

Figure 1

Puff profile diagrams (why square was favoured). Common puff profile algorithms for aerosol collection compared to possible device puff profile shape. In Figure a) the device has a relatively slow start-up. Square-shaped and bell-shaped machine profiles would give similar yield results. In Figure b) the device has a relatively quick start-up time, and the bell-shaped profile may give lower yields than the square-shaped profile.

Figure 2

Puff profile diagram. Puff block results example shown as (a) puff block to puff block yield trending and (b) cumulative yield.

Impact of puff frequency on yield_

Puffing regime	Puff count	Volume (mL/min)	Nicotine (mg/cig)	ACM (mg/cig)	Water (mg/cig)	Nicotine (mg/puff)	ACM (mg/puff)	Water (mg/puff)
55 / 3 / 30	60	110	1.2	73.2	12.5	0.020	1.22	0.21
55 / 3 / 60	60	55	1.0	63.9	11.0	0.016	1.07	0.18

Comparison of ACM composition across regimes_ Range in analyte percent composition across the regimes for each sample_

Sample	Total PG	Total nicotine	Total glycerin	Total water
Range of % Composition^a
Lab 1-Rechargeable	47–48	1.2–1.2	26–27	11–13
Lab 2-Disposable	56–58	1.8–1.9	28–29	8–11
Lab 2-Rechargeable	57–59	1.8–1.9	28–29	8–12
Lab 3-Disposable	NA^c	1.6–1.6	71–76	20–20
Lab 3-Rechargeable	NA	1.3–1.4	72–76	15–16
Lab 4-Disposable	42–47	1.0–1.2	33–39	15–18
Lab 4-Rechargeable	34–41	1.4–1.5	41–44	11–13
% Difference in % Compositionb
Lab 1-Rechargeable	3 %	2 %	4 %	21 %
Lab 2-Disposable	4 %	4 %	5 %	33 %
Lab 2-Rechargeable	3 %	3 %	4 %	32 %
Lab 3-Disposable	NA	1 %	6 %	3 %
Lab 3-Rechargeable	NA	2 %	7 %	9 %
Lab 4-Disposable	10 %	22 %	16 %	21 %
Lab 4-Rechargeable	19 %	8 %	6 %	17 %

Range in analyte percent composition across the regimes for each disposable sample_

Sample	Profile	Puff numbers
Sample	Profile	0–25	26–50	51–75	76–100	101–125	126–150	151–175	176–200	201–225	226–250	251–275
Lab 2-Disposable	55 / 3 / 30 / Sq	19	22	24	29	34	80% of all %RSD values <15%
	55 / 4 / 30 / Sq	6	6	5	7
	70 / 3 / 30 / Sq	6	9	9	15
	70 / 4 / 30 / Sq	6	6	7	7
Lab 3-Disposable	55 / 3 / 30 / Sq	6	8	9	9	11	13	9	9	19
	55 / 4 / 30 / Sq	12	13	11	12	12	13	15
	70 / 3 / 30 / Sq	8	11	14	17	18	20	15	18	18
	70 / 4 / 30 / Sq	7	11	12	13	17	18	19
Lab 4-Disposable	55 / 3 / 30 / Sq	10	8	6	8	6	8	5	5	9
	55 / 4 / 30 / Sq	6	6	8	5	8	7	4	5
	70 / 3 / 30 / Sq	3	5	4	4	4	4	6	5	22	8	20
	70 / 4 / 30 / Sq	13	13	12	11	7	12	14

Range in analyte percent composition across the regimes for each rechargeable sample_

Sample	Profile	Puff numbers
Sample	Profile	0–25	26–50	51–75	76–100	101–125	126–150	151–175	176–200	201–225
Lab 1-Rechargeable	55 / 3 / 30 / Sq	7	8	9	9	7	10	9	9
	55 / 4 / 30 / Sq	7	10	11	11	11	11
	70 / 3 / 30 / Sq	10	8	8	10	8	9	8	7
	70 / 4 / 30 / Sq	14	14	14	14	14	11
Lab 2-Rechargeable	55 / 3 / 30 / Sq	17	17	20	18	18	18	16	13
	55 / 4 / 30 / Sq	11	7	6	5	7	9
	70 / 3 / 30 / Sq	18	18	18	18	19	19	20	24	6
	70 / 4 / 30 / Sq	14	11	9	9	9	6
Lab 3-Rechargeable	55 / 3 / 30 / Sq	11	16	17	26	80% of all %RSD values <15%
	55 / 4 / 30 / Sq	10	8	7
	70 / 3 / 30 / Sq	11	12	13	17
	70 / 4 / 30 / Sq	11	7	8
Lab 4-Rechargeable	55 / 3 / 30 / Sq	6	5	7	6
	55 / 4 / 30 / Sq	7	6	5	4
	70 / 3 / 30 / Sq	7	6	7	5
	70 / 4 / 30 / Sq	7	7	5

E-cigarette weight loss vs_ ACM yield_ Ratio of e-cigarette weight loss to ACM collected – comparison across test regimes_

	Lab 1-Rechargeable	Lab 2-Disposable	Lab 2-Rechargeable	Lab 3-Disposable	Lab 3-Rechargeable	Lab 4-Disposable	Lab 4-Rechargeable
Test 1	1.0	1.0	1.0	1.1	1.0	1.0	0.9
Test 2	0.4	1.0	1.0	1.1	1.1	1.0	1.0
Test 3	1.0	1.0	1.0	1.1	1.1	1.0	0.9
Test 4	1.0	1.0	1.0	1.1	1.0	1.0	1.0

Product information_ List of e-cigarette products tested_

Sample ID	Sample Description^a
Lab 1-Rechargeable	Rechargeable product tested by Laboratory 1
Lab 2-Rechargeable	Rechargeable product tested by Laboratory 2
Lab 2-Disposable	Disposable product tested by Laboratory 2
Lab 3-Rechargeable	Rechargeable product tested by Laboratory 3
Lab 3-Disposable	Disposable product tested by Laboratory 3
Lab 4-Rechargeable	Rechargeable product tested by Laboratory 4
Lab 4-Disposable	Disposable product tested by Laboratory 4

Comparison of overall ACM across regimes_ Impact of regime choice on total ACM yield (mg)_

Sample		Regime 1	Regime 2	Regime 3	Regime 4	Range^a
Lab 1-Rechargeable	Avg	647	677	621	629	9%
	SD	46	60	45	74
	%RSD	7%	9%	7%	12%
Lab 2-Rechargeable	Avg	253	289	226	279	24%
	SD	60	14	25	13
	%RSD	24%	5%	11%	5%
Lab 2-Disposable	Avg	537	590	542	611	13%
	SD	79	30	79	48
	%RSD	15%	5%	15%	8%
Lab 3-Rechargeable	Avg	377	416	370	369	12%
	SD	35	52	50	44
	%RSD	9%	13%	14%	12%
Lab 3-Disposable	Avg	234	267	268	270	14%
	SD	46	30	39	22
	%RSD	20%	11%	14%	8%
Lab 4-Rechargeable	Avg	258	303	265	284	16%
	SD	9	17	17	11
	%RSD	4%	6%	6%	4%
Lab 4-Disposable	Avg	891	924	870	942	8%
	SD	118	70	111	162
	%RSD	13%	8%	13%	17%

Regimes specifications_ Puffing parameters for aerosol collection_

Regime	Code	Puff volume (mL)	Duration (s)	Shape	Frequency	Mean flow (mL/s)
Regime 1	55 / 3 / 30 / Sq	55	3	Square	Every 30 s	18.3
Regime 2	55 / 4 / 30 / Sq	55	4	Square	Every 30 s	13.8
Regime 3	70 / 3 / 30 / Sq	70	3	Square	Every 30 s	23.3
Regime 4	70 / 4 / 30 / Sq	70	4	Square	Every 30 s	17.5
ISO-like^a	35 / 2 / 60 / B	35	2	Bell	Every 60 s	17.5
CI-like^a	55 / 2 / 30 / B	55	2	Bell	Every 30 s	27.5

Impact of profile shape on yield_ Varied puff profile shape with a short puff duration – aerosol nicotine yield (mg) ± SD_

Pad	Profile^a

	Bell-shaped	Triangle-shaped	Square-shaped
1^st 50 puffs	0.48 ± 0.12	0.58 ± 0.19	0.69 ± 0.14
2^nd 50 puffs	0.38 ± 0.11	0.33 ± 0.12	0.54 ± 0.14
3^rd 50 puffs	0.24 ± 0.10	0.28 ± 0.10	0.34 ± 0.11
4^th 50 puffs	0.29 ± 0.08	0.24 ± 0.09	0.38 ± 0.10
5^th 50 puffs	0.25 ± 0.07	0.22 ± 0.07	0.38 ± 0.07
6^th 50 puffs	0.20 ± 0.06	0.19 ± 0.07	0.30 ± 0.07
7^th 50 puffs	0.19 ± 0.06	0.19 ± 0.06	0.28 ± 0.06
8^th 50 puffs	0.17 ± 0.05	0.15 ± 0.05	0.23 ± 0.05
400 puffs total	2.19 ± 0.64	2.17 ± 0.74	3.14 ± 0.69

Impact of puff frequency on yield_ Impact of puff collection period on yield collected during a day or across a week_

Puff blocks	35 mL, 1 day	55 mL, 1 day	65 mL, 1 day	35 mL, 1 week	55 mL, 1 week	65 mL, 1 week
1^st 90 puffs	116.9	133.5	140.9	115.8	130.4	137.9
2^nd 90 puffs	101.2	109.6	115.6	100.1	107.9	116.3
3^rd 90 puffs	88.9	94.2	97.4	84.7	89.4	97.8
4^th 90 puffs	71.7	80.0	80.8	72.8	76.0	83.5
Total	378.6	417.2	434.7	373.3	403.7	435.5