C8-C26 branched and linear hydrocarbons – Distillates

Toxicity to aquatic algae and cyanobacteria

Description of key information

Key information: 
- (72h) ErL50 for algae (Raphidocelis subcapitata): >1000 mg/l  [OECD 201; test mat. (WAFs) (nominal) based on: growth rate];
- (72h) NOELR for algae (Raphidocelis subcapitata): ≥100 mg/l [OECD 201; test mat. (WAFs) (nominal) based on: growth rate].
Supporting information: 
- (72h) ErL50 for algae (Selenastrum capricornutum): >1000 mg/l  [US EPA Algal Bottle Test; test mat. (WAFs) (nominal) based on: growth rate];
- (72h) NOELR for algae (Selenastrum capricornutum): ≥100 mg/l [US EPA Algal Bottle Test; test mat. (WAFs) (nominal) based on: growth rate].

Additional information

The acute toxicity of a sample of GTL Gasoil (Shell SMDS-2) has been determined by Palmer (2001) in a test with the unicellular alga Raphidocelis subcapitata. The tests were conducted in accordance with OECD Test Guidelines 201.

WAFs of the sample were prepared in sealed vessels with minimum headspace by stirring for approximately 72 hours. The contents of the vessels were left to stand for 1-2 hours before drawing off the aqueous phase – the WAF – for testing. Static exposures were then carried out in completely full, sealed vessels. The tests were not subject to GLP and the test media were not analysed for stability or for exposure concentration of the test substance. However in other respects they were considered to fulfil the requirements of current best practice.

The test results, expressed as the EL₅₀and NOEL values, showed that the sample was not acutely toxic to algae at a loading rate of 1000 mg/l.

Albertus and Phillips (2005) have reported results for anacute toxicity test carried out ona second sample of GTL Gasoil (SASOL SPD™ Diesel) with the freshwater alga Selenastrum capricornutum.

The test was carried out using a scaled-down version of the US EPA algal bottle test method. In all cases the test media were water-accommodated fractions of the test sample that were prepared in sealed vessels with a small headspace according to the CONCAWE methodology for the ecotoxicological testing of petroleum products (CONCAWE report, 1993).

The test results, expressed as the EL₅₀ and NOEL values, showed that the sample was not acutely toxic to algae at a loading rate of 1000 mg/l.

The following information is taken into account for toxicity to aquatic algae and cyanobacteria:

(72-h) E_rL₅₀>1000 mg/l WAFs R. subcapitata

Value used for CSA:

72-h E_rL₅₀for freshwater algae: >1000 mg/l (WAFs)

72-h NOELR for freshwater algae: ≥1000 mg/l (WAFs).