Urea is normally a normal body constituent and is constantly being produced during amino acid and protein metabolism. It is a natural constituent in commonly consumed foods. Several grams per kilogram of body weight can be ingested by nonruminants, including man, without untoward effects. Most of the nitrogen consumed in food is excreted in the form of urea. A 70 kg individual consuming a normal diet will excrete an average of 25g urea daily. While urea appears to be teratogenic in chick and frog embryos, no teratogenic effects were observed after ingestion of large doses of urea by pregnant rats and cows.
If all urea not used in animal feed and fertilizer were utilized in human food, it would amount to about 5g per capita daily. However, it is known that the majority of this urea is used for the production of urea formaldehyde resins and other non food ingredients is much less than 5g daily.
In the light of the foregoing, the Select Committee concludes that: There is no evidence in the available information on urea that demonstrates, or suggests reasonable grounds to suspect, a hazard to the public when it is used at levels that are now current or that might reasonably be expected in the future.