December 2003


Six breakthrough studies on the environmental safety of linear alkylbenzene sulfonate (LAS) – one of the most widely-used surfactants in the world – are available in the latest issue of The CLER Review (Vol. 8, No. 1) the technical journal of the Council for LAB/LAS Environmental Research (CLER).

The studies include a landmark, three-part study demonstrating the safety of LAS and other major surfactants for onsite wastewater treatment systems (including septic systems), which are used in over 25 million households in the US, and millions more worldwide. It was conducted on a site that typified the “worst-case” scenario – a household septic system in sandy soil where the groundwater level is extremely shallow during rainy seasons – and concluded that LAS is readily removed from the groundwater, even in these cases. The study was conducted by the US Soap and Detergent Association.

Other highlights in the current issue of the Review include:

  • A comprehensive study of a model stream ecosystem (a mesocosm), which examined the effects of LAS on over 250 species of aquatic organisms over a 56-day period, establishing a highly reliable safe, or predicted no-effect concentration for LAS in the freshwater environment. 
  • A definitive, real-world study on LAS in sewage sludge, confirming that levels of LAS typically found in sludge-amended soils are safe for the environment.
  • A study that corrects the record about a frequently-cited, unpublished report of high concentrations of LAS found in marine sediments off the coast of Denmark. The new study finds that the analytical method of the Danish study was seriously flawed, and that LAS levels in marine sediments are in fact so low they are generally undetectable.

“The studies in this issue of The CLER Review illustrate both the high quality of the scientific information available on LAS, and the depth of our understanding of the environmental safety of LAS,” said Dr. John Heinze, CLER’s technical director and editor of the Review.

Copies of the CLER Review are available by contacting Francie Israeli at 202-737-0171 or sending an email request to