No histological abnormality
was found 30 minutes after infusion of
10 mL d-limonene into the duodenum
of rats.13 In pigs, 20 mL d-limonene was
infused into the gallbladder once daily
for two days. Twenty-four hours after
the last infusion, histological examination found no
abnormality in the mucosa of the gallbladder, common
bile duct, or duodenum, which were directly in contacted
with d-limonene.14 In dogs, 10 mL d-limonene
was infused daily for seven days via a cholecystostomy
tube. On the day following the last infusion, no major
abnormality was found except slight inflammatory cell
infiltration and fibrosis in the duodenal papilla