2. Health risk assessment – systemic effects (1) REMINDER OF INHALED DOSE PO intake is 7.2 mg/day 0.12 mg/kg bw/day for a 60-kg adult 2

3. Health risk assessment – systemic effects (2) ADME data lacking but absorption likely to be extensive after inhalation Assume 100% absorption through lungs Risk assessment is limited by lack of inhalation data. Endpoint data limited. Reproductive/developmental toxicity only at maternally toxic dose levels 3

4. Health risk assessment – systemic effects (3) Respiratory tract and skin sensitisation reactions seen following ingestion/inhalation of PO containing products Genotoxicity/carcinogenicity data are reassuring (supported by menthol studies) PO likely to lack significant mutagenic character - risk assessment can be based on a threshold effect Oral NOAEL of 100 mg/kg bw/day identified 4

5. Health risk assessment – systemic effects (4) Useful inhalation data exist on menthol Rats inhaled l-menthol for up to 52 exposures (6.75 hr/day, 5 days/wk) Detailed histopath showed only local effects – lung congestion/inflammation at 1.6 mg/m 3, not at up to 0.9 mg/m 3 5

6. Health risk assessment – systemic effects (5) Systemic NOAEC = 1.6 mg/m 3, 6.75 hr/day, 5 days/wk for about 10 wk (i.e. subchronic) First, convert to an NOAEL 6

7. Health risk assessment – systemic effects (6) REACH default - rat inhales 0.29 m 3 /kg bw over 6 hr So in 6.75 hr, a rat inhales 0.522 mg/kg bw (1.6 x 0.29 x 6.75/6) = study NOAEL Next, a factor to convert to 7 days/wk dosing NOAEL = 0.522 mg/kg bw/day x 5 days/7 days = 0.37 mg/kg bw/day 7

8. Health risk assessment – systemic effects (7) Next, convert to chronic value using REACH AF of 2 Lifetime NOAEL = 0.19 mg/kg bw/day Apply traditional AFs of 10 for interspecies and 10 for intraindividual differences 8

9. Health risk assessment – systemic effects (7) Human HCV = 1.9 μg/kg bw/day The inhaled dose is roughly 60 times higher than the derived HCV However, this is not necessarily a “fail”. A more detailed assessment is required. 9

10. The rats could probably have coped with higher doses but it is often challenging to obtain sufficiently ‑ high atmospheric concentrations Moreover, the local effects were limiting Menthol systemic “LOAEC” in mice at a much higher conc (100 mg/m 3 ) Health risk assessment – systemic effects (8) 10

11. Turn to oral data on PO for additional risk insights Key is the 90-day study with PO in rats NOAEL = 40 mg/kg bw/day (or 100 mg/kg bw/day if brain effects considered artefacts) JECFA suggests effects at top dose were not adverse (i.e. NOAEL could be higher than 40 or even 100) Health risk assessment – systemic effects (9) 11

12. Generate an oral TDI from 13-wk study NOAEL 40 or 100 mg/kg bw/day Apply AFs of 10/10 for inter- and intra- species Apply 2 for the use of a subchronic study Oral TDI = 0.2-0.5 mg/kg bw/day This is 1.7-4.2 times higher than the (inhaled) dose Health risk assessment – systemic effects (10) 12

13. Derive long-term inhalation DNEL from the study No information regarding absorption of PO so use REACH defaults of 50 and 100 for the oral and inhalation routes respectively Essentially divide oral TDI by a factor of 2 Inhalation DNEL = of about 0.1-0.25 mg/kg bw/day (comparable to 0.12 mg/kg bw/day dose) Health risk assessment – systemic effects (11) 13

14. PO intake from flavouring use 1.18 mg/kg bw/day = ~70 mg for a 60-kg adult 10x higher than the 7.2 mg/day e- liquid dose Health risk assessment – systemic effects (12) 14

15. Systemic health risk overview table BenchmarkRelevant route Benchmark (mg/kg bw/day) Exposure (mg/kg bw/day MoE Diet (PO)Oral1.180.129.8 Bibra DNEL from 10- wk inhalation study on menthol Inhalation 0.0019 (menthol) (systemic LOAEL not achieved) 0.120.016 Bibra DNEL from 90- day oral study on PO Oral0.2-0.50.121.7-4.2 Bibra DNEL from 90- day oral study on PO Inhalation0.1-0.250.120.8-2.1 TERA OARS WEEL (menthol) Inhalation1.1 (6.4 mg/m 3 ) (menthol) 0.129.1 Summary table showing Margins of Exposure Conclusion: unlikely to pose any systemic toxicity risks 15

16. Systemic health risk overview Some uncertainty over this conclusion For example, no AF used for database limitations (due to “read-across” from menthol) Reduce uncertainty by assessing each component e. g. Menthol – good database, no AF needed for study quality - provides reassurance on the menthol portion (60% perhaps?) Carry out similar assessments for all components, down to TTC Conclusion: unlikely to pose any systemic toxicity risks 16

17. Health risk assessment – respiratory tract irritation (1) REMINDER OF INHALED CONCENTRATION PO intake of 7.2 mg/day Total puff volume = 0.033 m 3 Assumed even distribution in puffs Puff PO concentration = 218.2 mg/m 3 17

18. Health risk assessment – respiratory tract irritation (2) No inhalation data on PO PO no EU CLP harmonised classification 135 EU suppliers 0/135 respiratory tract irritant 113/135 (~ 84%) as a skin irritant 6/135 (~ 4%) as an eye irritant 18

19. Health risk assessment – respiratory tract irritation (3) Based on menthol inhalation data, PO is likely to possess potential to cause respiratory tract irritation Is this likely at puff concentration of 218.2 mg/m 3 ? 19

20. Health risk assessment – respiratory tract irritation (4) Ideally Quantify the main constituents Search for data on these compounds e.g. use menthol Profile 20

21. Health risk assessment – respiratory tract irritation (5) For menthol Mice - 100 mg/m 3 for 15 mins – mild irritation – changes in respiratory function TERA WEEL values imply: No irritation in workers at 6.4 mg/m 3 for 8 hr No irritation in workers at 19.2 mg/m 3 for 15 mins 21

22. Health risk assessment – respiratory tract irritation (6) For menthol Exposure at 19.2 mg/m 3 for 15 mins Would supply a menthol dose of 6 mg menthol (1.25 m 3 x 15 mins/60 mins x 19.2 mg) 22

23. Health risk assessment – respiratory tract irritation (7) For menthol Respiratory tract irritation risk depends upon delivery rate, tissue area and exposure time If 6 mg delivered over 15 mins does not irritate Then 7.2 mg delivered over 16 hr is unlikely to irritate 23

24. Health risk assessment – respiratory tract irritation (8) Consumer use - peak PO exposure at 218.2 mg/m 3 Such exposure will last for a few seconds, for 2/12 breaths during each minute Lasting maybe 10-40 minutes, repeated several times each day 24

25. Health risk assessment – respiratory tract irritation (9) Useful to consider ratio of exposure to non-exposure parameters Take a single “intense” 40 ‑ minute session Ratio of e-cigarette exposure to non- exposure time is 1/5 (400 seconds/2000 seconds; assuming a 5-second puff exposure) 25

26. Health risk assessment – respiratory tract irritation (10) Ratio of exposure puffs to non ‑ exposure breaths is 1/5 (80/400) Ratio of exposure puff volume to non-exposure breath volume is 1/150 (0.0044 m 3 /0.6623 m 3 ) [worst-case] The 0.6623 m 3 figure is calculated by subtracting the total exposure puff volume in the 40 ‑ minute intense period from the total inhaled volume in 40 minutes (assuming a 1 m 3 per hour inhalation rate during the 16-hr day) 26

27. Health risk assessment – respiratory tract irritation (11) Take the full 16-hr daily use period Ratio of e-cigarette exposure to non-exposure time is 1/18 (3000 seconds/55,200 seconds) Ratio of exposure puffs to non ‑ exposure breaths is 1/18 (600/11,040) Ratio of exposure puff volume to non- exposure breath volume is 1/480 (0.033 m 3 /15.97 m 3 ) 27

28. Health risk assessment – respiratory tract irritation (12) Would the PO exposure irritate respiratory tract? Unclear! Menthol data indicate the puff concentration could irritate on exposures that are not brief But only 80/480 exposure breaths (in a 40-min session) or 600/11,520 breaths (over 16 hr) 28

29. Health risk assessment – respiratory tract irritation (12) TERA estimates that delivery of 6 mg over 15 mins would not irritate Exposure involves dose of 7.2 mg over 16 hr (menthol – not PO!) Reason to anticipate exposure would not irritate – Clinical trials? 29

30. Health risk assessment – respiratory tract irritation (13) If PO were to dissolve in saliva then local tissues might experience an average concentration of around 0.003% during use PO inhaled at 24 μg/min (7.2 mg/day x 2 puffs/min / 600 puffs/day) Saliva produced at 0.69 mL/min (1000 mL/1440 min) 24 μg/0.69 mL = 34 μg/mL, or 0.0034 g in 100 mL i.e. 0.003% - unlikely to irritate 30

31. Health risk assessment – respiratory tract irritation (14) Conclusion: Due to brief and intermittent nature of puff exposures, it seems unlikely that the menthol would lead to significant respiratory tract irritation Can this be extrapolated to PO? Assess other components The occasional case of respiratory sensitisation may occur 31