Reaction mass of cerium phosphate and lanthanum phosphate and terbium phosphate

Endpoint summary

Additional information

All the data available on reaction mass of lanthanum phosphate and cerium phosphate and terbium phosphate were quoted as reliability 1 according to Klimisch criteria and flagged as key studies. Only the data used in a read-across approach to conclude on chronic aquatic toxicity were scored with a reliability 2 and flagged as supporting studies.

Short-term toxicity to fish:

The acute toxicity of reaction mass of lanthanum phosphate and cerium phosphate and terbium phosphate to rainbow trout (Oncorhynchus mykiss) was determined in a 96-hour semi-static test according to the EU Commission Directive 92/69/EEC, Part C.1 (1992), and the OECD Guideline for Testing of Chemicals No. 203 (1992). Rainbow trouts were exposed to control and test chemical at a nominal loading rate of 100 mg/L. The test fish were observed after approximately 3, 24, 48, 72 and 96 hours test duration for mortality and visible abnormalities.

No mortality or visible abnormalities were determined in the control and at the loading rate of 100 mg/L during the 96h-period.

The 96-hour NOELR and the 96-hour LL0 of reaction mass of lanthanum phosphate and cerium phosphate and terbium phosphate to rainbow trout were determined to be ≥ 100 mg/L (measured test item concentration of 264 μg/L). The 96-hour LOELR, the 96-hour LL50 and 96-hour LL100 were > 100 mg/L or higher than mean measured test item concentration of 264 μg/L.

 

Short-term toxicity to aquatic invertebrates:

The acute toxicity of reaction mass of lanthanum phosphate and cerium phosphate and terbium phosphate to Daphnia magna was determined in a 48-hour static test according to the EU Commission Directive 92/69/EEC, Part C.2 (1992) and the OECD Guideline for Testing of Chemicals, No. 202 (2004). Daphnids were exposed to control and test chemical at a nominal loading rate of 100 mg/L for 48 hr (mean measured concentration of 45 µg/L). Mortality/immobilization were observed daily. 

In the control and at the loading rate of 100 mg/L, no immobilized test organisms were determined during the test period of 48 hours. The 48 hour LL50 and NOELR were thus > 100 mg/L and ≥ 100 mg/L, respectively.

Toxicity to aquatic algae:

In a 72 hour acute toxicity study, the cultures of green algal species Scenedesmus subspicatus were exposed to reaction mass of lanthanum phosphate and cerium phosphate and terbium phosphate at the loading rate of 100 mg/L under static conditions in accordance with the EU Commission Directive 92/69/EEC, C.3 (1992), and the OECD Guideline 201 (2006). 

Reaction mass of lanthanum phosphate and cerium phosphate and terbium phosphate had no toxic effect on Scenedesmus subspicatus up to the highest concentration which could be tested at a loading rate of 100 mg/L (corresponding to a mean measured concentration of 42 µg/L). The NOELR , the LOELR and EL50 values based on the growth (AUC, growth rate and yield) were ≥ 100 mg/L, > 100 mg/L and > 100 mg/L, respectively.

 

Toxicity to micro-organisms:

The activated sludge respiration inhibition test was waived according to column 2 of Annex VIII of REACH regulation as reaction mass of lanthanum phosphate and cerium phosphate and terbium phosphate is highly insoluble in water (2.06 µg/L at 20°C, RCC Study n° B39150, 2008, GLP), so that microbial toxicity is unlikely to occur.

Long-term aquatic toxicity:

Reaction mass of lanthanum phosphate and cerium phosphate and terbium phosphate is highly insoluble and presents no acute aquatic ecotoxicity. Furthermore, two supporting studies were provided in order to show that the insoluble compounds of cerium and lanthanum show no chronic toxicity to daphnids reproduction and survival up to and including the water solubility limit. From these data, it can be expected that the insoluble reaction mass of lanthanum phosphate and cerium phosphate and terbium phosphate should present a similar absence of long-term aquatic toxicity. From these elements and in accordance with the REACH principle intended to limit vertebrate testing (in the case of the fish test waiving), the chronic toxicity studies on fish and daphnids were waived.