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Environmental fate & pathways

Endpoint summary

Administrative data

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Additional information

Guanidine chloride is inherently biodegradable. This was shown in a non guideline, read-across study with Guanidine nitrate (Mitchell 1987). Test conditions especially test substance concentration and bacteria concentration are comparable to guideline OECD301, inoculum is expected to be adapted.

Guanidine chloride is also biodegradable under less favourable conditions as was demonstrated in degradation tests with 14-C Guanidine in river water and aerated soil (Mitchell, Chemosphere (1987), Mitchel, Bull. Environ. Contam. Toxicol. (1987)).

With these test results, Guanidine chloride can be regarded as "rapidly degradable" according to GHS regulation.

Justification for read-across:

Guanidine hydrochloride and guanidine nitrate dissociate in aqueous media to yield the guanidine ion and the respective anion. Therefore it is reasonable to discuss the effects of the ions separately. The chloride ion is a naturally occurring essential ion in human beings with well-known metabolism and mechanisms of action as described in standard textbooks on pharmacology and physiology. As well it is found as salt in the Earth´s crust and is dissolved in seawater. Effects of guanidine hydrochloride are expected to be based primarily on the guanidine ion. The physiological processing of the guanidine ion is expected to be independent of the individual source. Therefore read-across from guanidine hydrochloride for effects of guanidine dissociated from guanidine nitrate is considered valid. This strategy is supported by a quite similar toxicological profile of both substances, as shown in acute toxicity, irritation, sensitization and genotoxic studies.

A more detailed justification is attached and outlined in CSR chapter 1.1.2 as well.