1 In order to study the antigenotoxic potential of eugenol in humans,
ten healthy non-smoking males ingested a daily amount of 150 mg eugeno
l or the placebo for seven consecutive days. After a washout period of
one week, groups ingesting eugenol or the placebo were crossed and re
ceived the other treatment for seven consecutive days. 2 On days 8 and
22 blood samples were taken for the assessment of standard clinical b
iochemical parameters. To study the possible antigenotoxic effect of e
ugenol, on day 8 and 22 blood samples were collected and exposed in vi
tro to the established genotoxic agents mitomycin C and vinblastine. A
fter exposure the percentage of cells with chromosome aberrations and
micronuclei was determined in cultured white blood cells. On days 8 an
d 22 paracetamol (500 mg p.o.) was administered as test substance to m
easure phase-II biotransformation capacity. Glutathione-S-transferase
(GST) activities were determined in erythrocytes and blood plasma. 3 N
o significant differences in the clinical biochemical parameters were
detected between the eugenol-period and the placebo-period, indicating
that daily administration of 150 mg eugenol for 7 days has no toxic a
ffects. 4 No significant differences on the cytogenetic parameters wer
e found after ingestion of eugenol. Thus, there are no indications for
an antigenotoxic potential of eugenol in humans, consuming daily 150
mg eugenol for 7 days. 5 A significant reduction in alpha-class GSTs i
n plasma (P<0.05), but not in the other measured biotransformation par
ameters, was found in volunteers during the eugenol-period as compared
to the placebo-period. This may either reflect GST-inhibition by euge
nol or protection against background damage of liver cells by eugenol.