Registration Dossier

Environmental fate & pathways

Endpoint summary

Administrative data

Description of key information

Additional information

Available literature on phototransformation of thiourea in air reports that the substance is degraded from 0.23 to 4.7 % under the conditions of the GSF test (Schmidt-Bleek et al., 1982) and when irradiated at a wavelength of 290 nm (Freitag et al., 1985), respectively. In addition, Meylan & Howard (1993; as cited in the Hazardous Substances Data Bank) determined an atmospheric half-life t1/2 of about 3 hours at an atmospheric concentration of 5.0E+05 hydroxyl radicals per cm³.

Regarding the phototransformation of thiourea in water, the calculated half-life of thiourea in sunlit natural water at a hydroxyl radical concentrations of 1.0E-17 M is 171 days (HSDB, citing results of Mill et al. (1980).

HSDB states that Kolyada observed measurable degradation in sterilized soils, although the mechanism for the degradation was not studied. The extent of degradation is also not reported.

Two data sources are available that describe the hydrolysis of thiourea at different pH. Schmidt-Bleek et al. (1982) report that thiourea is stable to hydrolysis at pH 4, 7, and 9. These results are consistent with the findings of Korte & Greim (1981) who observed no hydrolysis of thiourea at pH 1.2, 3, 7, and 9 under the conditions of OECD guideline A-79.74D.