Chromium tris(dihydrogen phosphate)

Long-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Endpoint:

long-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Remarks:

Peer Reviewed publication

Justification for type of information:

As with all inorganic salts, the significance for toxicity or environmental assessment is the presence of specific ions that will form when in solution or when in biological systems.In the case of Cr III salts, the counter ion will have an effect on solubility and this is itself dependant on the type of media being used and in particular the pH of that media. It is generally accepted that in the case of metal salts, testing with salts that are soluble in the respective test media will ensure maximum exposure of the metal ions. This will include chlorides and nitrates as being more soluble and will indeed have relevance when dissolved in acid media, such as if ingested.Read-across to other chromium III salts is therefore considered valid as long as the exposure in the test system is greater than wold be expected for the substance under review for registration.
Peer reviewed research following regulatory methods.

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 211 (Daphnia magna Reproduction Test)

Principles of method if other than guideline:

In accordance with provisional procedures approved by Umweltbundesamt (as of January 1984)

GLP compliance:

no

Specific details on test material used for the study:

Hydrated form use. Cr Cl3 6H2O

Analytical monitoring:

yes

Remarks:

Details not specified

Details on sampling:

Samples taken on two occaisions during the test; day 7 and day 16

Vehicle:

no

Details on test solutions:

Concentration range 0.08 - 11 mg/l as Cr
Concentration range 0.43 - 55 mg/l as Cr Cl3 6H2O

Test organisms (species):

Daphnia magna

Details on test organisms:

IRCH Strain

Test type:

semi-static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

21 d

Hardness:

Synthetic water DIN 1982a, bMg / Ca ions at 2.5 mmol

Test temperature:

20 C

pH:

8 +/- 0.2

Dissolved oxygen:

Aerated to saturation

Nominal and measured concentrations:

Concentration range 0.08 - 11 mg/l as CrConcentration range 0.43 - 55 mg/l as Cr Cl3 6H2O

Duration:

21 d

Dose descriptor:

NOEC

Effect conc.:

0.7 mg/L

Nominal / measured:

nominal

Conc. based on:

element

Remarks:

Chromium

Basis for effect:

reproduction

Key result

Duration:

21 d

Dose descriptor:

NOEC

Effect conc.:

ca. 3.5 mg/L

Nominal / measured:

nominal

Conc. based on:

other: Chromium hydrogen phosphate

Basis for effect:

reproduction

24 hour EC50 reported as 22 mg/l Cr3+

No further information

Validity criteria fulfilled:

not specified

Conclusions:

The 21 day NOEC (reproduction) for chromium 3+ was 0.7 mg/l and 24 hr EC50 (immobilisation) was 22 mg/l.
The NOEC (reproduction) for chromium hydrogen phosphate is estimated as 2.6 mg/l

Executive summary:

Investigations were carried out in order to determine the “no observed effect concentration” (NOEC) of 73 environmentally relevant substances in the 21 d Daphniareproduction test. The test was conducted in line with the provisional procedure proposed by the Federal Environmental Agency (Umweltbundesamt) (as of 1 January 1984). Daphnia magna Straus was used as the test organism. Evaluation parameters for fixing the NOEC were the mortality of the parent animals, the reproduction rate and the appearance of the first offspring during the test period. The concentrations of substances in the test preparations were chemically quantified.

The 21 day NOEC (reproduction) for chromium 3+ was 0.7 mg/l and 24 hr EC50 (immobilisation) was 22 mg/l.

Description of key information

The 21 day NOEC (reproduction) for chromium 3+ was 0.7 mg/l and 24 hr EC50 (immobilisation) was 22 mg/l.

The NOEC (reproduction) for chromium hydrogen phosphate is estimated as 2.6 mg/l

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

2.6 mg/L