Sulfuric acid, mono-C16-20-alkyl esters, sodium salts

Toxicity to microorganisms

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

toxicity to microorganisms

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Comparable to national guideline study with acceptable restrictions

Justification for type of information:

Refer to the Category Approach Justification document provided in IUCLID6 Section 13.

Qualifier:

according to guideline

Guideline:

other: cell multiplication inhibition test acc. to Bringmann and Kühn (1977)

GLP compliance:

not specified

Analytical monitoring:

not specified

Vehicle:

not specified

Test organisms (species):

Pseudomonas putida

Test type:

not specified

Water media type:

freshwater

Total exposure duration:

18 h

Duration:

18 h

Dose descriptor:

NOEC

Effect conc.:

550 mg/L

Nominal / measured:

nominal

Conc. based on:

act. ingr.

Basis for effect:

growth inhibition

Reference 2

Endpoint:

toxicity to microorganisms

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

key study

Justification for type of information:

Refer to the Category Approach Justification document provided in IUCLID6 Section 13.

Reason / purpose for cross-reference:

read-across source

GLP compliance:

not specified

Test organisms (species):

Pseudomonas putida

Water media type:

freshwater

Total exposure duration:

18 h

Duration:

18 h

Dose descriptor:

NOEC

Effect conc.:

550 mg/L

Nominal / measured:

nominal

Conc. based on:

act. ingr.

Basis for effect:

growth inhibition

Description of key information

18h NOEC (Pseudomonas putida) = 550 mg/L (growth inhibition, read-across)

Key value for chemical safety assessment

EC10 or NOEC for microorganisms:

550 mg/L

Additional information

Since no reliable toxicity tests with microorganisms are available for C16-20AS Na (CAS 91648-55-4), in accordance to Regulation (EC) No. 1907/2006 Annex XI, 1.5 a read-across to another structurally related substance was conducted. Read-across data available for C16-18AS Na (CAS 68955-20-4) were used. Toxicity of alkyls sulfates is dependent on the carbon chain length - homologues of chain length of C13 to C15 are considered as the most toxic from the whole Alkyl Sulfate Category. Toxicity of the chains from C16 and higher will decrease due to lower bioavailability as a consequence of reduced water solubility.

One reliable study with Pseudomonas putida is available for C16-18AS Na (CAS 68955-20-4). The key study (Steber 1988) followed the procedure of cell multiplication inhibition test according to Bringmann and Kühn (1977). The growth inhibition of Pseudomonas putida was recorded after 18 hours of exposure to the test substance. The 18-hour NOEC value was determined to be 550 mg a.i./L (nominal concentration).

Due to structure and property similarities with the tested category member it can be concluded that the above result applies also to C16-20AS Na (CAS 91648-55-4). The 18-hour NOEC value for microorganisms is 550 mg/L. This value was used for the PNEC STP derivation for C1620AS Na (CAS 91648-55-4).