The Contribution of cocoa additive to cigarette smoking addiction

Page 136 of 207 RIVM report 650270002
Tyramine
Not possible.
COMMERCIAL USE
Tyramine hydrochloride solution (Mydrial-Atropin) is used for production of
mydriasis (45).
BENEFICIAL EFFECTS
No data available.
Critical assessment
Not relevant.
Conclusion
Not relevant.
SUMMARY AND FINAL CONCLUSION
Tyramine is a natural tobacco component and is also added to tobacco as a
component of cocoa powder, which is used as flavouring agent. The estimated
tyramine amount in dried tobacco plant is ± 400 µg/g dry weight. The average
amount of tyramine in cocoa varies from 0.73 – 14.7 µg/g. Tyramine is found in fish
and fish products, ripening and processed cheese, yeast, wine, cabbage and
sauerkraut, and tomato paste. An intake of > 40 mg biogenic amines (histamine,
tryptamine, tyramine, phenylethylamine, etc.) per meal has been considered
potentially toxic. The estimated tyramine amount in cigarettes from tobacco plant is
at least 2700 times higher than the tyramine amount from added cocoa. Therefore, it
is debatable whether tyramine should be considered as an additive to tobacco. The
daily potential intake of tyramine from cigarettes (from tobacco plant and from
cocoa) (10 mg/25 cigarettes/day) is higher than tyramine intake from other sources
such as chocolate (2.6 mg/3 bars) or wine (0.2 mg/glass), and is comparable with
cheese (10 mg/50g). The plasma concentration reached after ingestion of tyramine
from chocolate or other food sources is expected to be lower or equal to tyramine
after exposure from cigarettes, assuming similar bioavailability and no loss by
combustion. Also the different route of application via smoking as compared to other
sources should be taken into account. Therefore, the systemic and the local effect of
smoking related exposure to tyramine might be a point of concern. Since nothing is
known about the pyrolysis/combustion products of tyramine, this may also be a point
of concern.
Tyramine is an indirect acting sympathomimetic substance. It increases the release of
noradrenaline from the neural endings. The main pharmacological effect of tyramine
is the increase of the blood pressure. About 21 mg tyramine (i.v. in 15 min) increased
the systolic blood pressure significantly. It is unlikely that tyramine dose in cigarettes
(estimated 0.4 mg/cigarette) will exert a significant increase in systolic blood
pressure. Based on the mechanism of action of tyramine by releasing noradrenaline
from the neural endings, it is expected that the dose of tyramine in cigarettes will not
have a significant effect on the bronchial function.
Oral tyramine is largely metabolised by the MAO-enzymes in the intestines. No data