[No public or meaningful name is available]

Biodegradation in water: screening tests

Administrative data

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

key study

Study period:

Feburary to March 2019

Reliability:

1 (reliable without restriction)

Justification for type of information:

Read across from an structural analogue.

Cross-reference

Reason / purpose for cross-reference:

read-across source

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2019

Report date:

2019

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 301 D (Ready Biodegradability: Closed Bottle Test)

Deviations:

yes

Remarks:

Deviations detailed in the appendix 7 and 8 of the attached report.

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

2,6-bis[[bis(2-hydroxyethyl)amino]methyl]-4-nonylphenol

EC Number:

243-500-6

EC Name:

2,6-bis[[bis(2-hydroxyethyl)amino]methyl]-4-nonylphenol

Cas Number:

20073-51-2

Molecular formula:

C25H46N2O5

IUPAC Name:

2,6-bis{[bis(2-hydroxyethyl)amino]methyl}-4-nonylphenol

Test material form:

liquid: viscous

Specific details on test material used for the study:

Test item name: Poliol MB 600
CAS number 20073-51-2
EC number 243-500-6

Batch lot number 7590
Analysed purity 99.6% (according to CoA)
Manufactured by Sistemas ecológicos de poliuretano, sl
Supplied to JRF by Sistemas ecológicos de poliuretano, sl
Date of manufacture December 12, 2018
Date of Expiry December 12, 2019
Other Characteristics: Water solubility 1.3x10-3 mol/L
Appearance/Colour Viscous liquid, dark yellow, slightly like formaldehyde
Storage condition at JRF
As per instruciton received from the Sponsor on storage of the test item, the test item was stored:
Storage temperature: Room temperature
Storage container: In original container as supplied by the sponsor
Storage location: Test item control office, JRF

Study design

Oxygen conditions:

aerobic

Inoculum or test system:

other: secundary effluent from a treatment plant

Details on inoculum:

Preparation, pre-conditioning and analysis of inoculum
Secondary effluent from the JRF Sewage Treatment Plant treating predominantly domestic sewas was used as the inoculum. The secondary effluent was filtered through a Whatman Nº1 filter paper. The inoculum was pre-conditioned by aerating at 22+- 2ºC for 8 days. The inoculum was analysed for microorganisms concentration and confirmed as 3.10 x 10^4 CFU/mL

Duration of test (contact time):

ca. 28 d

Initial test substance concentration

Initial conc.:

ca. 2 mg/L

Parameter followed for biodegradation estimation

Parameter followed for biodegradation estimation:

O2 consumption

Remarks:

ThOD

Reference substance

Reference substance:

benzoic acid, sodium salt

Results and discussion

% Degradation

% Degradation 1

Key result

Parameter:

% degradation (TOC removal)

Value:

ca. 14.79

Sampling time:

7 d

% Degradation 2

Key result

Parameter:

% degradation (TOC removal)

Value:

ca. 14.44

Sampling time:

14 d

% Degradation 3

Key result

Parameter:

% degradation (TOC removal)

Value:

ca. 19.54

Sampling time:

21 d

% Degradation 4

Key result

Parameter:

% degradation (TOC removal)

Value:

ca. 20.32

Sampling time:

28 d

BOD5 / COD results

BOD5 / COD

Key result

Parameter:

BOD5

Value:

ca. 0.8 mg O2/g test mat.

Remarks on result:

other: measured on day 7

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Interpretation of results:

not readily biodegradable

Conclusions:

The percent biodegradation data concluded that the Poliol MB 600 is not readily biodegradable. The test item showed a maximum degradation of 20.32% on day 28, whereas the reference substance exhyibited a normal pattern of degradation (up to 93.34%) within 28 days. The percent degradation by the toxicty control was greater than 25% after 14 days. Therefore, the test item was regarded as not readily biodegradable and not toxic to microorganism in the inoculum.

Executive summary:

EXECUTIVE SUMMARY: The ready biodegradability of Poliol MB 600 was determined in a closed bottle test in accordance with OECD test guideline 301D at a concentration of 2.0 mg/L in mineral medium inoculated with secondary effluent from a treatment plant (1 mL/L). Sodium benzoate was used as  reference substance to check the validity of the method. Mineral medium with inoculum (1 mL/L) without test item and Sodium benzoate served as an inoculum blank and mineral medium with inoculum (1 mL/L) and silicon oil was served as test blank. Separate test solutions were maintained in parallel (in duplicate) for test, reference and control samples for observation on day 0, 7, 14, 21, and 28.  

 

During the experiment, the residual concentration of oxygen in test bottles on day 28 was 6.66 mg/L (guideline limit >0.5 mg/L at all times). The percent biodegradation data revealed that Poliol MB 600 was not readily biodegradable. The maximum degradation was 20.32% on day 28. The biological degradation of the test item with time is given in the below table:  

 

Treatment	% Degradation (Based on ThOD) on day
	7	14	21	28
Procedure control	73.53	78.03	90.04	93.34
Test solution	14.79	14.44	19.54	20.32
Toxicity control	22.91	29.77	-	-

The ThOD value for the test and reference item was 2.569 mg O2/mg and 1.666 mg O2/mg, respectively.  

Based  on  the  results  of  this  test,  the  test  item  was  not  readily  biodegradable  and  not  toxic  to microorganisms in the inoculum.