LINEAR ALKYLBENZENE SULFONATE (LAS) - UNEP Chemicals

OECD SIDS LINEAR ALKYLBENZENE SULFONATE (LAS)
III. Description of Model and Status of Peer Review and Validation
(1) Tool or Model
The modeling presented here uses simple, first principle equations, which err on the side of being
protective.
General Exposure Model
Potential Chemical Exposure (PE) =
Exposure to Product (EXP) x Chemical Concentration in Product Formulation (PF)
Dermal Route – Product Specific Models
1. Exposure during the activity/use of diluted and undiluted laundry and dishwashing
products, and diluted and undiluted hard surface cleaning products
[FQ x CA x PC x FT x CF x TF x DA] x PF
BW
2. Exposure to laundry and fabric conditioning product residual on clothing
[A x PR x PT x DA x CF] x PF
BW
[“FQ” frequency of use is 1 wash load/day for clothing]
3. Exposure to face and hand soap residual after use
Where:
[FQ x A x PR x DA x CF] x PF
BW
FQ: frequency of use (use/day)
CA: body surface contact area (cm 2 )
PC: product concentration (g/cm 3 )
FT: film thickness on skin (cm)
CF: conversion factor (1000 mg/g)
TF: time scaling factor (unitless)
DA: dermal absorption (%)
BW: female body weight (kg)
PF: LAS concentration in product formulation (%)
A: amount per use (g/day or g/wash)
T: transfer to skin (%)
PR: percent retained on clothing or on skin (%)
PT: percent transferred from clothing to skin (%)
(2) Validation/Peer Review
These exposure calculations use first principle equations and are mathematically consistent with the EPA
Exposure Guidelines (1992) with regard to modeling dermal doses.
(3) Availability and Documentation
USEPA 1992. Guidelines for Exposure Assessment. [FRL-4129-5]
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