LINEAR ALKYLBENZENE SULFONATE (LAS) - UNEP Chemicals

OECD SIDS LINEAR ALKYLBENZENE SULFONATE (LAS)
estimation does not account for biodegradation during transport to the wastewater treatment plant (HERA
2004).
(3) Model Outputs
Results following wastewater treatment; where 50 th percentile represents a facility on a mid-size stream
with average flow.
Aquatic exposure -
50 th percentile facility -
Mean stream concentration = 4.8 µg/L
7Q10 stream concentration = 13 µg/L
[7Q10 is the lowest 7-day average flow in a year that occurs on an average once every 10 years ]
Drinking water exposure -
50 th percentile facility -
Average Daily Dose (ADD) =
9.3E-07 mg/kg/day (chronic non-cancer)
Fish consumption exposure –
50 th percentile facility -
Average Daily Dose (ADD) =
3.5 E-05 mg/kg/day (chronic non-cancer)
(4) Reliability Score 2 (Reliable with restrictions) The model has not been validated but is sufficiently
conservative and accepted by authorities. Appropriate inputs have been selected reflecting best available
information and conservative estimates where applicable.
Modeling can be useful in first tier approach for exposure assessment. Model outputs reflect E-FAST
model assumptions that are designed to provide high end to bounding estimates of exposure.
(5) Remarks
The aquatic NOEC = 270 µg/L. The estimated mean and low flow (7Q10) stream concentrations are 4.8
µg/L and 13 µg/L, respectively, for the 50 th percentile scenario.
An appropriate NOAEL from animal studies for comparison is 85 mg/kg (see reasons stated in the
SIAR). Estimated exposures in consumer products for the 50 th percentile facility scenario are 9.3E-07
mg/kg/day (drinking water) and 3.5E-05 mg/kg/day (fish consumption).
Product formulation facilities are not expected to have environmental releases that exceed those for LAS
manufacturing facilities.
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