Environmental Executive Summary
Alkyl Sulphates (AS) are a widely used class of anionic surfactants. They are used in household cleaning products, personal care products, institutional cleaners and industrial cleaning processes, and as industrial process aids in emulsion polymerisation and as additives during plastics and paint production. Uses in household cleaning products (the scope of HERA) include laundry detergents, hand dishwashing liquids, and various hard surface cleaners.
The HERA AS family encompasses commercial grades of linear-type primary alkyl sulphates in the C12 to C18 range. This assessment does not cover the AS present as a component of another major class of anionic surfactants, Alcohol Ethoxysulphates (AES). This will be covered separately, as part of the HERA AES risk assessment.
The total volume of AS surfactants used in Europe is estimated to be 102,000 tonnes/year on an active matter basis based on a survey of producers (1999). Based on a survey conducted among detergent formulator companies, and input from AS producers, the tonnage used in household detergents and cleaning products is estimated to be approximately 65,000 tonnes/year.
A large environmental data set is available for Alkyl Sulphates. On the environmental fate side, this includes standard biodegradation studies, advanced simulation studies of removal in treatment systems, and field monitoring data. On the environmental effects side, acute as well as chronic single-species data are available, as well as advanced studies in micro- and mesocosm systems.
Chemical removal in wastewater treatment plants was determined from advanced simulation test data, and to determine the ecotoxicological Predicted No Effect Concentrations, chronic ecotoxicity data were used.
Monitoring studies on sewage treatment plant effluents indicate that the exposure estimates in this assessment are likely to be conservative. In addition, mesocosm studies suggest that the effects assessment based on laboratory studies is also conservative.
By means of higher tier exposure and effects data, it could be shown that the use of Alkyl Sulphates in HERA applications (household detergents and cleaning products) poses no concern in any environmental compartment.
An additional exposure scenario was included in this risk assessment, by assuming the entire AS tonnage used in Europe is disposed of down the drain, rather than just the HERA tonnage. Using the same exposure and effects assessment approach, the absence of environmental concerns can also be demonstrated for the total tonnage.