LINEAR ALKYLBENZENE SULFONATE (LAS) - UNEP Chemicals

OECD SIDS LINEAR ALKYLBENZENE SULFONATE (LAS)
Analytical monitoring: Yes [ ] No [X] ? [ ]
Method: open-system [X]; closed-system [ ]
Algal growth inhibition test (88/302/EWG) 1988.
Nominal test concentrations were control, 0.6, 2.4, 10, 40, and 160 mg/L.
Algae were exposed to LAS in Erlenmeyer flasks in an environmental
chamber on a light table at 8000 lux. Cell numbers were photometrically
determined (8 subsets were taken for each concentration).
GLP: Yes [X] No [ ] ? [ ]
Test substance: Marlon A 390 (CAS #68411-30-3) C10-13 LAS, average alkyl chain length =
11.6; 91.3% activity
Remarks: Initial cell concentrations were 20,000 cells/mL. Cell concentrations at 72 h
were 95, 89, 85, 75, 48 and 8 (all x 10 4 /mL) for the control, 0.6, 2.4, 10, 40
and 160 mg/L LAS concentrations, respectively. The pH ranged from 7.7 to
7.9 at the beginning of the study and 7.9 to 9.0 at the end of the study. Test
temperature was maintained at 24 ± 2 °C. This is a key study for aquatic
toxicity to algae (see SIAR Table 12).
Reference: Scholz, N. 1992. Bestimmung der Auswirkungen von Marlon A 390 auf das
Wachstum von Scenedesmus subspicatus 86.81. SAG
(Algenwachstumshemmtest nach Richtlinie 88/302/EWG) Huels Final
Report No. AW-291.
Reliability: 1 Valid without restriction
(g)
Species: Scenedesmus subspicatus (Algae)
Endpoint: Biomass [X]; Growth rate [X]; Other [ ]
Exposure period: 72 hour
Results: ErC50 (growth rate) = 82 mg/L; EbC50 (biomass) = 20 mg/L
NOEC (growth rate) = 0.4 mg/L; NOEC (biomass) = 0.1 mg/L
Inhibition of cell growth by concentration and duration is shown in the table
below:
Cell number ( x 10 4 cells/mL)
Time Period (hours)
Test concentration
(mg/L)
0 24 48 72
Control 2 9 32 94
0.1 2 9 32 91
0.4 2 9 29 88
1.6 2 9 28 76
6.4 2 9 24 60
25 2 9 21 54
160 2 6 7 7
Analytical monitoring: Yes [X] No [ ] ? [ ]
Method: open-system [X]; closed-system [ ]
Algal growth inhibition test (92/69/EWG)
Nominal test concentrations were control, 0.1, 0.4, 1.6, 6.4, 25 and 160 mg/L.
Test concentrations were measured at 0 and 72 h and found to confirm the
nominal concentrations. Algae were exposed to LAS in Erlenmeyer flasks in
an environmental chamber on a light table at 8000 lux. Cell numbers were
photometrically determined (8 subsets were taken for each concentration).
GLP: Yes [X] No [ ] ? [ ]
Test substance: Marlon A 350 (CAS #68411-30-3) C10-13 LAS, average alkyl chain length =
11.6; 52.1% activity
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