Use of this information is subject to copyright laws and may require the permission of the owner of the information, as described in the ECHA Legal Notice.
EC number: 200-315-5
CAS number: 57-13-6
Urea is of very low acute toxicity by all routes investigated. The acute oral LD50 of urea is reported to be 14.3-15.0 g/kg bw in the rat and 11.5-13.0 g/kg bw in the mouse. The acute subcutaneous LD50 is reported to be 8.2-9.4 g/kg bw in the rat and 9.2-10.7 g/kg bw in the mouse. The acute intravenous LD50 of urea is reported to be 5.3-5.4 g/kg bw in the rat and 4.6-5.2 g/kg bw in the mouse.
Acute oral toxicity
Urea is of very low acute oral toxicity in the rat and mouse. Sato et
al (1977) report LD50 values of 14.3 (12.9 -15.9) and 15.0 (13.4
-16.8) g/kg bw in male and female rats; LD50 values of 11.5 (10.6 -12.5)
and 13.0 (11.0 -15.4) g/kg bw in the mouse. Urea is of generally low
acute oral toxicity in most species but higher toxicity is noted in
ruminants due to the generation of ammonia by gastric flora. Stiles et
al (1970) report an LDlo of approximately 600 mg/kg bw in cattle.
Acute dermal toxicity
No data are available: a waiver is proposed for this endpoint. Urea is
demonstrated to be of very low acute toxicity by the oral, subcutaneous
and intravenous routes in the rat and mouse. Testing for acute dermal
toxicity is not justified on scientific grounds and for reasons of
animal welfare. Specifically, the very low toxicity of urea by the
subcutaneous and intravenous routes indicates that dermal toxicity would
also be very low, even assuming rapid and total dermal penetration.
Acute inhalation toxicity
No data are available: a waiver is proposed for this endpoint. The
substance is a non-volatile solid and is produced as crystals with a
particle size of >100 µm. There is therefore no potential for inhalation
exposure. In addition, the substance has been demonstrated to be of very
low toxicity by other routes of exposure. Testing for acute inhalation
toxicity is therefore not justified on scientific grounds or based on
Acute toxicity by other routes of exposure
Urea is also of very low acute toxicity by the subcutaneous route. Sato et
al (1977) report LD50 values of 9.4 (8.2 -10.8) and 8.2 (7.1 -9.5)
g/kg bw in male and female rats and LD50 values of 9.2 (8.6 -9.8) and
10.7 (9.5 -12.1) g/kg bw in male and female mice. It is notable that the
subcutaneous LD50 values are greatly in excess of the limit dose for
acute dermal toxicity testing.
Urea is of very low toxicity following intravenous administration. Sato et
al (1977) report LD50 values of 5.4 (4.9 -5.9) and 5.3 (4.8 -5.7)
g/kg bw in male and female rats and LD50 values of 4.6 (4.3 -4.9) and
5.2 (4.8 -5.6) g/kg bw in male and female mice, respectively.
Urea is of inherently very low toxicity by all routes investigated. No
data are available for the inhalation route, however low toxicity can
also be predicted for this route. No classification is proposed for
acute toxicity according to CLP.
Information on Registered Substances comes from registration dossiers which have been assigned a registration number. The assignment of a registration number does however not guarantee that the information in the dossier is correct or that the dossier is compliant with Regulation (EC) No 1907/2006 (the REACH Regulation). This information has not been reviewed or verified by the Agency or any other authority. The content is subject to change without prior notice.Reproduction or further distribution of this information may be subject to copyright protection. Use of the information without obtaining the permission from the owner(s) of the respective information might violate the rights of the owner.
Welcome to the ECHA website. This site is not fully supported in Internet Explorer 7 (and earlier versions). Please upgrade your Internet Explorer to a newer version.
Do not show this message again