EXCRETION OF (14)C-FORMALDEHYDE DISTRIBUTED SYSTEMICALLY THROUGH ROOT-CANAL FOLLOWING PULPECTOMY

The fate and excretion of C-14-labeled formaldehyde, when applied as f ormocresol in the root canals of cat's canines, was examined using a c hamber apparatus for the collection of the cat's respiratory CO2. Six cats divided into two groups of three were used. Four mu l or 8 mu l o f formocresol was applied per root canal. Seventy-two h after formocre sol application, the accumulated recovery rate of (CO2)-C-14 represent ed 21.9% of total dose in the 4 mu l group and 35.4% in the 8 mu l gro up. Samples were collected after 72 h from blood and urine, and from l ung, liver and kidney tissue, C-14-radioactivity was detected in all s amples. The percentage of the total dose in each organ was very low an d there was no significant difference between the 4 mu l and 8 mu l gr oups. These results suggested that when formocresol was medicated into the cat's canine canals following pulpectomy, formaldehyde was distri buted in the body and rapidly metabolized and excreted.