Registration Dossier

Administrative data

Hazard for aquatic organisms

Freshwater

Hazard assessment conclusion:
no hazard identified

Marine water

Hazard assessment conclusion:
no hazard identified

STP

Hazard assessment conclusion:
no hazard identified

Sediment (freshwater)

Hazard assessment conclusion:
no hazard identified

Sediment (marine water)

Hazard assessment conclusion:
no hazard identified

Hazard for air

Air

Hazard assessment conclusion:
no hazard identified

Hazard for terrestrial organisms

Soil

Hazard assessment conclusion:
no hazard identified

Hazard for predators

Secondary poisoning

Hazard assessment conclusion:
no potential for bioaccumulation

Additional information

Guanidine hydrochloride was evaluated to be inherently biodegradable. There are 3 acute tests (fish, daphnia, algae) and 2 chronic tests (fish, daphnia) with freshwater organisms available, the lowest obtained chronic value is the NOEC of 2.9 mg/L for Daphnia magna. Terrestrial toxicity data are available for plants and soil microorganisms (both acute and chronic), the lowest available value is the NOEC = 435 mg/Kg soil ww for terrestrial plants.

Short-term toxicity to aquatic organisms:

Fish: LC50 (96 h) = 690 mg/L a.i. for Pimephales promelas (test with read-across substance Guanidine nitrate).

Invertebrates: EC50 (48h) = 70.2 mg/L for Daphnia magna (test with read-across substance Guanidine nitrate, similar to OECD 202). Algae and cyanobacteria: ErC50 (72 h) = 33.5 mg/L for Pseudokirchneriella subcapitata (test with read-across substance Guanidine nitrate, according to EU C.3)

Long-term toxicity to aquatic organisms:

Fish: NOEC = 181 mg/L for Fathead minnow (test with read-across substance Guanidine nitrate, similar to OECD 210). Invertebrates: NOEC = 2.9 mg/L for Daphnia magna (test with read-across substance Guanidine nitrate, similar to OECD 211).

Biodegradation in water:

In a study similar to OECD 301, readily biodegradation was shown. However, bacteria naturally occurring in river water were used, downstream a guanidine emitting site, and thus the inoculum is expected to be adapted. For this reason, the substance is classified as inherently instead of readily biodegradable.

Bioaccumulation:

Based on the log Kow below 0, the substance will have a low potential for bioaccumulation in aquatic organisms and a low potential for adsorption to organic matter of soils and sediments at environmental relevant pH values. Based on the available information, there is no indication of a bioaccumulation potential in organisms and, hence, secondary poisoning is not considered as relevant.

Terrestrial toxicity:

Toxicity to terrestrial plants: NOEC = 435 mg/Kg soil ww; wheat germination, seeding groth (test with read-across substance Guanidine nitrate, similar to OECD 210). The test is regarded to cover acute effects and can be used as estimate of chronic toxicity following ECHA Guidance Chapter R.7c (2008). (Remark: key value for chemical safety assesment NOEC 435 mg/kg is wet weight; pick list doesn't allow to choose ww but dw)

Toxicity to terrestrial microorganisms:

NOEC = 636 mg/Kg soil ww; natural soil microorganism (test with read-across substance Guanidine nitrate, similar to OECD 210). (Remark: key value for chemical safety assesment NOEC 636 mg/kg is wet weight; pick list doesn't allow to choose ww but dw)

Conclusion on classification

According to experimental results, Guanidine chloride is inherently biodegradable. Acute and chronic results for species for all 3 tropic levels are above 1 mg/l. Following these findings an environmental classification according to current CLP legislation, EU GHS (Regulation (EC) No 1272/2008, 3. ATP) is not necessary.