Metabolic fate of ethylenethiourea in pregnant rats

Abstract

Metabolic fate of ETU was investigated in the rats administered orally 100 mg/kg of C14-ETU on the twelfth day of gestation. ETU was absorbed readily from the gastrointestinal tract and passed away from the whole body tissues including the fetus rapidly. Only the exception was the thyroid gland and the radio-activity was accumulated in the gland. Most of the administered activity (80.2%,4,5-C14-ETU) was eliminated into the urine in 24 hr and the tissues (including the fetus) levels of radioactivity from 2-C14-ETU reached maximal within 2 hr and fell down to negligible levels by 24 hr. Radiocarbon(s) of 4,5-C14-ETU was expired as radioactive carbon dioxide and was incorporated into the serum and fetal cell constituents (crude protein fraction), but that of 2-C14-ETU was neither expired or incorporated into the cell constituents. From the fetus extract ETU and several radioactive metabolites were detected.

Urinary excretion of ethylenethiourea and kidney morphology in rats after continuous oral exposure to nabam or ethylenethiourea

“…The present results are consistent with the earlier finding that orally administered ETU is rapidly excreted in urine (Newsome 1974;Kato et al 1976). On an average, 25-49% of a daily dose on continuously administered ETU was excreted as such.…”

“…In rats and cats, the main route of elimination of ETU is via urine (Kato et al 1976;Ruddick et al 1976;Allen et al I978). The present results are consistent with the earlier finding that orally administered ETU is rapidly excreted in urine (Newsome 1974;Kato et al 1976).…”

Correlation between blood ethylenethiourea and thyroid gland disorders among banana plantation workers in the Philippines.

“…In one study (Kato et al 1976), after only 5 min, ETU appeared in the blood of rats administered an oral dose of 100 mg 14 C-ETU/kg body weight. Within 48 hr, 82-99% of the oral dose was eliminated via urine and about 3% was eliminated via feces.…”

Biomonitoring of Contemporary Pesticides: Ethylenethiourea in Occupational Settings

“…On average, 7.5% of an EBDC dose administered is metabolized to ETU. ETU is predominantly (90%) eliminated in the urine and it has been found to have a half-life of about 28 hours in monkeys, 9 to 10 hours in rats, and 5 hours in mice (Newsome, 1974;Kato et al, 1976;Ruddick et al, 1976;Allen et al, 1978;Rose et al, 1980). ETU is also a metabolic product of EBDC in mammals, plants, and other organisms (WHO, 1988).…”