LINEAR ALKYLBENZENE SULFONATE (LAS) - UNEP Chemicals

OECD SIDS LINEAR ALKYLBENZENE SULFONATE (LAS)
Reliability: 2 Valid with restrictions
(b)
Type: Animal [ ]; Aquatic [X]; Plant [ ]; Terrestrial [ ]; Other [ ]
Methods: Fathead minnows (Pimephales promelas) were exposed to LAS in a flowthrough
system according to OECD guideline 305E.
Results: Steady state uptake was achieved by 96-h of exposure. Uptake constants (k1)
range from 4.3 to 642.2 L/kg/day with C11 and C13 having the lowest and
highest, respectively. The elimination rate constants (k2) range from 0.5 and
1.5 days. k1 was dependent on hydrophobicity and alkyl chain length. k2 did
not vary with hydrophobicity.
Reference: Tolls, J., Haller, M., De Graaf, I., Thijssen, M.A.T.C., and Sijm, D.T.H.M.
1997. Bioconcentration of LAS: Experimental determination and
extrapolation to environmental mixtures. 31:3426-3431.
Reliability: 2 Valid with restrictions
(c)
Type: Animal [ ]; Aquatic [X]; Plant [ ]; Terrestrial [ ]; Other [ ]
Method: In a flow-through system a 14 day uptake experiment was conducted with
fish (Pimephales promelas). Two concentrations of 0.100 and 0.135 mg/L
(0.3 and 0.4 uM) were tested resulting in concentration factors. Tissue
extracts of the fish exposed to LAS were analysed by desulfonation-GC.
Flow-through; water renewal rate: 3-4 renewals per day; no feeding;
hardness 250 mg/L; well water. Chemical analyses by LSC.
Results: On the basis of the concentration in fish tissues (wet weight) and the two
concentrations in water concentration factors in muscle were 4 and 3, and in
the gall bladder 13,700 and 7,500. It remains unclear whether the observed
variation of the concentration factors indicates a concentration dependence of
bioaccumulation. The results indicate metabolic transformation, since the
parent compound radioactivity could not account for all the radioactivity in
the fish. Percentages of radioactivity accounted for by parent LAS in muscle
50-70%, other organs 50-80%, gall bladder