Sodium [4-[[dihydroxy[(2-hydroxy-3,5-dinitrophenyl)azo]phenyl]azo]benzenesulphonato(3-)]cuprate(1-)

Biodegradation in water: screening tests

Link to relevant study record(s)

Reference

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

key study

Study period:

July 27, 2016 - Nov 25, 2016 (28 days)

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 301 B (Ready Biodegradability: CO2 Evolution Test)

Version / remarks:

OECD 301 B:1992

Deviations:

no

GLP compliance:

yes

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge (adaptation not specified)

Details on inoculum:

- Source of inoculum/activated sludge: Dihua sewage treatment plant, Taiwan.

Duration of test (contact time):

29 d

Initial conc.:

1 g/L

Based on:

test mat.

Parameter followed for biodegradation estimation:

CO2 evolution

Reference substance:

acetic acid, sodium salt

Remarks:

Sodium aceate

Key result

Parameter:

% degradation (CO2 evolution)

Value:

ca. 6

Sampling time:

29 d

Results with reference substance:

At Day 14 during the study, the biodegradation was 69.55 %.

At the end of the test, the CO2 production of blank control groups were 38.09 mg/L.

Table 1. The percentage biodegradation of the test groups.

Day	Percentage biodegradation (% ThCO2)^a
	Test group
	Flask 1	Flask 2	Mean	Difference of replicate^b
2	2.96	2.14	2.55	0.82
5	3.78	3.57	3.68	0.20
7	4.29	4.70	4.49	-0.41
9	4.19	5.21	4.70	-1.02
14	3.88	4.90	4.39	-1.02
19	4.90	5.51	5.21	-0.61
23	4.80	6.23	5.51	-1.43
27	4.90	7.96	6.43	-3.06
29	5.21	7.66	6.43	-2.45

^a Percentage of biodegradation (% ThCO₂) = (cumulative CO₂of test group (mg) -cumulative CO₂of blank control group (mg)) / (added TOC (mg) × 3.67) ×100%

^b Difference of replicate = Flask 1- Flash 2

Table 2: the percentage biodegradation of the reference and toxicity control group

Day	Percentage biodegradation (% ThCO2)^a
	Reference control group	Toxicity control group
	Flask 5	Flask 6
2	15.89	5.79
5	41.07	17.79
7	56.32	25.46
9	64.53	29.37
14	69.55	41.40
19	71.47	31.51
23	71.79	31.04
27	74.03	30.67
29	74.77	31.25

^a Percentage of biodegradation (% ThCO₂) = (cumulative CO₂of reference control group or toxicity control (mg) - cumulative CO₂of toxicity control group (mg)) / (added TOC (mg) × 3.67) ×100%

 

Validity criteria fulfilled:

yes

Interpretation of results:

inherently biodegradable, not fulfilling specific criteria

Conclusions:

According to OECD 301B test method, Everlan SL65 was not be considered readily biodegradable.

Executive summary:

This test using the procedures outlined in the SuperLab Study Plan for M62-151100111001EN which is based on the SOP for the OECD 301B (SOPE-503) and OECD 301B (OECD, 1992). The results of this OECD 301B test for Everlan SL65 show that all validity criteria were met. Everlan SL65 was not be considered readily biodegradable under the test conditions and the percentage biodegradation of Everlan SL65 in sludge was less than 60 %.

Description of key information

Not readily biodegradable (OECD TG 301B).

Key value for chemical safety assessment

Biodegradation in water:

inherently biodegradable, not fulfilling specific criteria

Additional information

The total amount of evolved CO2 in the blank control group was 38.09 mg/L. The difference between replicates of test group was less than 20%. At Day 14 during the study, the biodegradation of the reference control article was 69.55 % and the percent biodegradation in the toxicity control was 31.40 %. All test validity criteria were met. Everlan SL65 was not be considered readily biodegradable under the test conditions and the percentage biodegradation of Everlan SL65 in sludge was less than 60 %.