Strontium hydrogen phosphate

Ecotoxicological Summary

Hazard for aquatic organisms

Freshwater

Hazard assessment conclusion:

no hazard identified

Marine water

Hazard assessment conclusion:

no hazard identified

STP

Hazard assessment conclusion:

no emission to STP expected

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

Conclusion on classification

Studies performed with the substance

In 3 short-term studies performed in accordance with the current OECD guidelines, the substance did not induce visible or lethal effects in carp, did not induce acute immobilisation of Daphnia magna and did not significantly inhibit the growth rate of Pseudokirchneriella subcapitata, up to a concentration present in a 0.45 μm filtered solution prepared at a loading rate of 100 mg/L.

The measured concentration of Strontium was 12 to 16 mg Sr/L at the start of these tests and remained stable during exposure (86-105% of initial). As the molecular weight of the substance and of Strontium is 183.6 and 88 g/mole, respectively, the measured acute L(E)C50’s, as well as the EC10 determined in the algae study, are >25 mg SrHPO4/L.

Metals strategy

The substance is an inorganic substance containing a metal (Strontium). Consequently any classification based on the metals strategy presented in the Guidance on the Application of the CLP criteria should also be investigated. In case of this particular substance any classification based on the Strontium (Sr) ion needs to be investigated, considering the rate and extent of transformation of this element from the substance.

Strontium has a low acute toxicity to freshwater organisms. Most available tests are based on strontium chloride, with 48 h and 96 h LC50s ranging from 75 to 910 mg Sr/L. There are no chronic no-observed-effect concentrations (NOECs) for aquatic organisms (Reference: WHO report on STRONTIUM AND STRONTIUM COMPOUNDS9 (Concise International Chemical Assessment Document 77);

http://www.inchem.org/documents/cicads/cicads/cicad77.pdf).

When correcting the lowest available acute L(E)C50 of Strontium (75 mg Sr/L) for the molecular weight of the substance, an acute ERVcompound of >100 mg/L is obtained.

Based on the low acute toxicity of Strontium and based on the EC10 determined in the algae study (>16 mg Sr/L), it is considered justified to conclude that the chronic ERVcompound can be considered to be >1 mg/L; a factor of 100 below the acute ERVcompound.

Conclusion

Based on all the available information, it is not considered justified to classify the substance for environmental effects:

Acute hazard

For algae, fish and daphnids the acute L(E)C50’s were >1 mg/L, the classification criterion for acute hazard. Also the acute ERVcompound, determined using the available acute L(E)C50s of Strontium, is >1 mg/L.

Chronic hazard

For algae, the EC10 was determined to be >1 mg/L, the classification criterion for chronic hazard (for non-rapidly degradable substances).

Also the chronic ERVcompound is considered to be >1 mg/L; a factor of 100 below the acute ERVcompound.

For fish and daphnids (for which no chronic NOEC or EC10 is available), the measured acute L(E)C50’s were determined to be>25 mg/L, while no effects were observed. At 25 mg/L, the substance did not induce visible or lethal effects in carp and the substance did not induce acute immobilisation of Daphnia magna. As the tests have been performed in accordance with the ECHA guidance, with the use of Water Accommodated Fractions, and there was no acute toxicity observed, the substance does not need to be classified.