Calcium dodecylbenzenesulphonate

Monitoring data

Administrative data

Endpoint:

monitoring data

Type of information:

other: published data

Adequacy of study:

supporting study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Justification for type of information:

C12 LAS; Linear Alkylbenzene Sulfonate (LAS)) is a very close analogue of Calcium dodecylbenzenesulfonate (CAS No 26264-06-2, EC Number; 247-557-8) ) and read-across is valid.

Data source

Reference

Reference Type:

publication

Title:

Fate of linear alkylbenzene sulfonate in the environment.

Author:

McAvoy, D.C., Eckhoff, W.S. and Rapaport, R.A.

Year:

1993

Bibliographic source:

Environ. Toxicol. Chem. 12:977- 987.

Materials and methods

Test guideline

Qualifier:

no guideline followed

Principles of method if other than guideline:

Surface water samples were collected in rivers at 50 locations in 11 states below wastewater treatment plants.

GLP compliance:

not specified

Type of measurement:

other: Rivers in U.S.A.

Media:

other: Influents, effluents, and surface water

Test material

Test material information

Constituent 1

Reference substance name:

C12-LAS

IUPAC Name:

C12-LAS

Test material form:

solid: compact

Details on test material:

Alkyl chain lengths of LAS averaged 12.0 carbon units

Results and discussion

Details on results:

Average LAS influent concentrations ranged from 4.2-5.7 mg/L among the various types of treatment plants. LAS removal rates averaged 99.3% for activated sludge (n = 15), 98.0-98.5% for lagoon/oxidation ditch (n = 14), 96.2% for rotating biological contact (n = 9) and 77.4% for trickling filters (n = 12). Concentrations of LAS below the mixing zone of wastewater treatment plants were generally below 50 μg/L, even though the samples were collected under low flow (i.e., low dilution) conditions. The mean surface water concentrations ranged from <10 to 330 μg/L, with mean values of 42 to 46 μg/L. The highest concentration was observed in a low (less than 3-fold) dilution irrigation canal below a trickling filter plant. All other values were <180 μg/L, with more than 80% of the sites below 50 μg/L.

Applicant's summary and conclusion

Executive summary:

Surface water samples were collected in rivers at 50 locations in 11 statesbelow wastewater treatment plants. Alkyl chain lengths of LAS averaged12.0 carbon units in most environmental compartments, with the exception ofsludge solids and river sediments, in which an enrichment of longer chainlengths was observed. Since several of the wastewater treatment plantsincluded in this study have dilution factors less than 3, these values includeworst case estimates.