Sodium D-glycero-D-gulo-heptonate

Short-term toxicity to aquatic invertebrates

Description of key information

The study was conducted according to GLP and according to OECD guideline 202. The test was actually conducted on the closely related structural surrogate sodium glucoheptonate. The test item was exposed to Daphnia magna for 48 hours under static test conditions. The EC50 value after 48 hours was 1000 mg ai/L and the NOEC was 1000 mg/ai/L.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

1 000 mg/L

Additional information

Read-across discussion:

In order to address ecotoxicological endpoints as part of the REACH registration of Sodium d-glycero-d-gulo-heptonate (target substance) it is proposed to read across data from Sodium glucoheptonate (source substance). The use of read across is within the spirit of REACH, in order to reduce animal testing where possible.

The source and target substances are structurally similar consisting of the alpha/ beta and alpha only form of the same isomer (respectively) and have the same molecular weight, the substances also have comparable physical chemical properties. Due to the similar properties shown between the two materials it is believed that the results obtained in the testing of sodium glucoheptonate (source substance) will be a reliable representation of the properties for sodium d-glycero-d-gulo-heptonate (target substance) to allow classification and labelling and for risk assessment purposes. Therefore read across is justified. The substance sodium d-glycero-d-gulo-heptonate is considered to have similar properties to sodium glucoheptonate and therefore is considered to be relatively harmless and would not be classified in accordance with Regulation (EC) No 1272/2008 (CLP).

Study discussion:

Introduction:

A study was performed to assess the acute toxicity of the test item to Daphnia magna. The method followed was designed to be compatible with the US EPA Draft Ecological Effects Test Guidelines OPPTS 850.1010 (April 1996) and the OECD Guidelines for Testing of Chemicals (April 2004) No 202, "Daphnia sp., Acute Immobilisation Test" referenced as Method C.2 of Commission Regulation (EC) No. 440/2008. The study was actually conducted on a similar test material (Sodium Glucoheptonate) and hence this is only why a klimisch reliability of 2 has been assigned to this endpoint. Please see our justifications for using read across within section 13.

 

Methods:

Following a preliminary range-finding test, twenty daphnids (4 replicates of 5 animals) were exposed to an aqueous solution of the test item at concentrations of 100, 180, 320, 560 and 1000 mg active ingredient (ai)/L for 48 hours at a temperature of 20°C to 21°C under static test conditions. The number of immobilized Daphnia were recorded after 24 and 48 hours.

 

Results:

The 48-Hour EC₅₀ for the test item to Daphnia magna based on nominal test concentrations was greater than 1000 mg ai/L. The No Observed Effect Concentration was 1000 mg ai/L.

 

Analysis of the test preparations at 0 and 48 hours showed measured test concentrations to range from 80% to 83% of nominal value and so the results are based on nominal test concentrations only.