LINEAR ALKYLBENZENE SULFONATE (LAS) - UNEP Chemicals

OECD SIDS LINEAR ALKYLBENZENE SULFONATE (LAS)
chain length of 11.2 and 13.3 were conducted concurrently, with the resultant
96 hour LC50 values of 12.3 and 0.86 mg/L, respectively.
Reference: Holman, W.F. and Macek, K.J. 1980. An aquatic safety assessment of linear
alkylbenzene sulphonate (LAS); chronic effects on fathead minnows. Trans.
Am. Fish. Soc. 109(1):122-131.
Reliability: 2 Valid with restrictions
(r)
Type of test: static [X]; semi-static [ ]; flow-through [ ]; other [ ]
open-system [X]; closed-system [ ]
Species: Pimephales promelas (Fish, fresh water)
Exposure period: 48 hour
Results: The following table shows the acute toxicity of the tested materials (LC50,
mg/L).
High molecular weight
LAS
Individual homologues
LAS
Fathead minnow LC50 (mg/L)
Average chain length 24 hour 48 hour
13.3 1.9 1.7
C10 10 48.0 43.0
C11 11 17.0 16.0
C12 12 4.7 4.7
C13 13 1.7 0.4
C14 14 0.6 0.4
Nonlinear LAS
components (DTIS)
C10 10 87.0 ± 7.5 86.1 ± 15.0
C12 12 24.8 ± 5.8 21.5 ± 5.5
C14 14 8.1 ± 5.1 5.3 ± 3.9
Model biodegradation
intermediates
C4 (SØ Butyrate) 4 ~10,000 ~10,000
C5 (SØ Valerate) 5 ~10,000 ~10,000
C11 (SØU) 11 85.9 ± 5.1* 76.6 ± 12.4*
*Subsequent repurification of this sample yielded a product with the same isomeric composition but
with LC50 values over 1000 mg/L for fatheads.
Analytical monitoring: Yes [X] No [ ] ? [ ] MBAS
Method: EPA-660/3-75-009 1975. Method for acute toxicity tests with fish,
macroinvertebrates and amphibians.
Acute toxicity tests were conducted on high molecular weight LAS,
individual pure homologues, non-linear LAS components (dialkyl tetralin or
indane sulfonates, DTIS), and model biodegradation intermediates
(sulfophenylundecane, SOU) in order to determine whether biodegradation
decreases toxicity. Toxicity tests were conducted in 5 L of 100 mg/L
hardness water using 5 fathead minnows per concentration.
GLP: Yes [ ] No [ ] ? [X]
Test substance: 1) High molecular weight LAS: Average chain length = 13.3; C11 1%, C12
8%, C13 52%, C14 39%
2) Individual LAS homologues of C10, C11, C12, C13, and C14
3) Nonlinear LAS components (DTIS)
4) Model biodegradation intermediates
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