Disodium sebacate

Toxicity to microorganisms

Link to relevant study record(s)

Reference

Endpoint:

activated sludge respiration inhibition testing

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

test procedure in accordance with national standard methods with acceptable restrictions

Remarks:

ISO 8192

Qualifier:

according to guideline

Guideline:

ISO 8192 (Water quality - Test for inhibition of oxygen consumption by activated sludge for carbonaceous and ammonium oxidation)

Version / remarks:

1986-07-15

GLP compliance:

no

Analytical monitoring:

no

Test organisms (species):

activated sludge, domestic

Test type:

static

Water media type:

freshwater

Details on test conditions:

TEST SYSTEM
- Sludge concentration (weight of dry solids per volume): 1.5 g/L

TEST CONCENTRATIONS
-Stock solution preparation: 1.250 g sample, ad 1L 80 mL (or aliquot) from this stock plus activated sludge, ad 100 mL

Key result

Duration:

3 h

Dose descriptor:

other: EC20

Effect conc.:

> 1 000 mg/L

Nominal / measured:

nominal

Basis for effect:

inhibition of total respiration

Remarks:

respiration rate

DOC (calculated) 590 mg/L

30 min values:
oxygen consumption (mg O2/L*h) 41,3
reference value (mg O2/L*h) 39,9
delta (%) 4
EC20 (determined graphically) > 1000 mg/L

3h values:
oxygen consumption (mg O2/L*h) 42,3
reference value (mg O2/L*h) 36,4
delta (%) 16
EC20 (determined graphically) > 1000 mg/L

Description of key information

No respiratory inhibition was documented after 3 h incubation of sebacic acid up to the highest test concentration in a study according to ISO 8192 (BASF SE, 1990).

Additional information

No data on aquatic toxicity with the salt disodium sebacate are available. Only data on the acid are available:

 

The 3 h acute toxicity of sebacic acid to domestic activated sludge was studied under static conditions according to ISO 8192 (BASF SE, 2009). Domestic activated sludge was exposed to sebacic acid for 3 h. No inhibitory effects on the respiration rate were observed. The nominal 3 h EC20 was extrapolated and determined at > 1000 mg/L.

However, according to ECHA guidance R7b effects can be extrapolated from the anion or cation, whichever has the most toxic effect, if no data are available on a salt.

If the effect is related to only one of the ions, the classification of the salt should use the effect concentration multiplied by the salt/ion molecular weight ratio.

The molecular weight ratio between salt and ion is 246 : 202 (1.22)

Based on this correction the IC 50 for disodium sebacate was determined to be > 1220 mg/L in the test with domestic sludge.