1-nitroguanidine

Endpoint summary

Additional information

The hydrolytical stability of nitroguanidine was determined in accordance with OECD guideline 111 at pH 4.0, pH 7.0 and pH 9.0. Test solutions were incubated at 25, 40 and 50 °C initially for seven days. Nitroguanidine concentrations did not change significantly at pH 4.0 and 7.0. Nitroguanidine concentration decreased significantly at pH 9.0 and 50 °C. Hydrolysis of nitroguanidine was found to be a reaction of pseudo first order. Half-lives t_1/2, are 26,660 h, 1,643 h, and 351 h at 25 °C, 40 °C, and 50 °C, respectively. Potential degradation products described in the literature (ammelide, ammeline, cyanamide, dicyandiamide, guanidinium, guanylmelamine and melamine) as well as nitrate, urea, ammonia and nitrite (non-GLP) were not detected or only in traces. Hence, no pathway of hydrolysis can be proposed.

Nitroguanidine is not biodegradable in OECD standard tests for ready and inherent biodegradability. Literature results confirm that nitroguanidine is not biodegradable under aerobic conditions, but indicate at the same time that nitroguanidine can be cometabolically degraded by activated sludge microorganisms under anaerobic (Kaplan et al., 1982) and aerobic (Haag et al., 1990 & Spanggord et al., 1987) conditions after acclimation.

As no experimental information on the adsorption/desorption characteristics of Nitroguanidine is available, adsorption/desorption characteristics for Nitroguanidine were derived based on non-experimental methods:

Nitroguanidine is a highly water-soluble, high nitrogen-containing organic substance. The aqueous solubility of Nitroguanidine is > 3 g/L. It is also very hydrophilic, judged by its log octanol-water partition coefficient of -0.815. The estimated Koc value is 4.06, as presented by the EPISuite™ QSAR/Property package, as distributed by the US EPA. According to the results presented by EPISuite™ it can be concluded that Nitroguanidine does not adsorb strongly to soil (or sediment). Moreover, due to its physico-chemical properties nitroguanidine is not expected to bioaccumulate in biological tissues either.

Therefore, there is no need to perform a (fish) bioaccumulation study or sediment/soil simulation testing. As such, there is no potential for exposure of sediment. Even in the event of a direct release of nitroguanidine to aqueous systems the nitroguanidine will remain in the aqueous phase. Moreover, Nitroguanidine is not used in ways that would potentially result in either direct or indirect emissions to soil and nitroguanidine will not adsorb to soil or sediment organic matter fractions. As such, there is no potential for exposure of soil, even in the event of a release of nitroguanidine to air or water (the nitroguanidine will enter into, or remain in the aqueous phase).