Trichlorooctylstannane

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:

28th June to 6th August 2002

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

Study conducted in compliance with agreed protocols, with minor deviations from standard test guidelines and/or minor methodological deficiencies, which do not affect the quality of the relevant results. This study was in accordance with the OECD principles of Good Laboratory Practice (GLP).

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2003

Report date:

2003

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 301 F (Ready Biodegradability: Manometric Respirometry Test)

Deviations:

yes

Remarks:

additional NaNO3 was added to the mineral medium to prevent nitrogen limitation

Principles of method if other than guideline:

No information.

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Trichlorooctylstannane

EC Number:

221-435-4

EC Name:

Trichlorooctylstannane

Cas Number:

3091-25-6

Molecular formula:

C8H17Cl3Sn

IUPAC Name:

trichlorooctylstannane

Constituent 2

Reference substance name:

MOTC

IUPAC Name:

MOTC

Details on test material:

- Name of test material (as cited in study report): trichlorooctylstannane
- Molecular formula (if other than submission substance): C8Hl7Cl3Sn
- Molecular weight (if other than submission substance): 338.3 g/mol
- Physical state: colourless liquid
- Analytical purity: 100%
- ThOD NH3: 1.16 mg O2/mg
- Solubility in water: 0.33 mg/L
- Melting point: <10 degrees C
- Density: 1.41-1.45 g/cm^3 (at 20 ºC)
- Storage temperature range: <-18 ºC
- Protect from light: yes
- ORTEP Lot no.: W 00/78
- Research production number: TF 03443
- Expiry date: 31 July 2004
- TNO test substance number: 2496
- Date of receipt: 31 July 2001
- Quantity: 5 x 100 g
- Supplier: ORTEP Association Stabilizer Task Force

Specific details on test material used for the study:

Details on properties of test surrogate or analogue material (migrated information):
No information

Study design

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, domestic (adaptation not specified)

Details on inoculum:

A sample of activated sludge was taken from an oxidation ditch situated in the municipality of Hazerswoude, the Netherlands, on June 26, 2002. The oxidation ditch is used to treat domestic waste water. The activated sludge was transported in a plastic flask and aerated until use. Beofre the start of the test, the dry weight of the sludge was determined to be 4.65 g/L. In order to yield a concentration of solids of approximately 30 mg/L, 1.96 mL sludge was added to 300 mL of mineral medium.

Duration of test (contact time):

39 d

Initial test substance concentration

Initial conc.:

43 mg/L

Based on:

test mat.

Parameter followed for biodegradation estimation

Parameter followed for biodegradation estimation:

O2 consumption

Details on study design:

TEST CONDITIONS
- Solubilising agent (type and concentration if used):
- Test temperature: 20.5 ºC
- pH: start of the study: 7.8 - 8.0; end of the study 6.4
- pH adjusted: no
- CEC (meq/100 g): not specified
- Aeration of dilution water: not specified
- Suspended solids concentration: 30 mg/L
- Continuous darkness: yes
- Other: not applicable


TEST SYSTEM
- Culturing apparatus: 500 mL glass flasks
- Number of culture flasks/concentration: 1 flask/concentration
- Method used to create aerobic conditions: not specified

Reference substance

Reference substance:

acetic acid, sodium salt

Results and discussion

% Degradation

Parameter:

% degradation (O2 consumption)

Value:

0.2

Sampling time:

39 d

Details on results:

The BOD values were 0.03, 0.01, 0.00 mg O2/flask after 14, 28, and 39 days of incubation. The corresponding biodegradation percentages were 45, 47 and 49%.

BOD5 / COD results

Results with reference substance:

The reference substance was sufficiently degraded within 14 days of incubation (78%). The cumulative oxygen consumption in the toxicity control (sodium acetate and test substance) was 19.5 mg O2/flask after 14 days which was slightly lower than that of the inoculum activity control with sodium acetate only (20.5 mg O2/flask). This indicated that the test substance slighlty inhibited the degradation of sodium acetate at the concentration tested. Based on the combined ThOD of both substances, a biodegradation >25 % was reached, which, according to the guidelines, means that the substance is considerd not toxic to the inoculum.

Any other information on results incl. tables

Table 1: Results of the inoculums activity and toxicity control tests with trichlorooctylstannane: mean values of the cumulative oxygen consumption (mg O₂/flask) and biodegradation as percentage of the ThOD_NH3 (mean values after 14, 28 and 39 days

Time days	Inoculum blank		Inoculum activity control^1		Toxicity control^2
	Without filter mg O2/flask	With filter mg O2/flask	mg O2/flask	Biodegradation ThOD %^4	mg O2/flask	Biodegredation ThOD%^3
14 (336 hours)	4.6	3.8	20.5	78	19.5	45
28 (672 hours)	6.3	5.5	22.8	82	22.1	47
39 (928 hours)	6.9	6.2	23.8	84	23.3	49

1 – 100 mg/L sodium acetate

2 – 100 mg/L sodium acetate + 43 mg/L trichlorooctylstannane

3 – Corrected for blank with filter

4 – Corrected for blank without filter

 

Table 2: Biodegredation of trichlorooctylstannane (43 mg/L) expressed as the BOD (mg O₂/mg) and as a percentage of its ThOD_NH3 (mean values).

Time days	BOD mg O2/mg	% Biodegradation ThODNH3
14 (336 hours)	0.03	2.5
28 (672 hours)	0.01	0.9
39 (928 hours)	0.00	0.2

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Interpretation of results:

other: not readily biodegradable

Conclusions:

The 60 % degradation criterion was not met under the conditions requireed by OECD Guideline 301F, even when the study was extended to 39 days. A maximum degradation of 3.2 % was reached after 18 days of incubation. After 28 days a degradation of 0.9% was noted. Trichlooctylstannane was considered not readily biodegradable.

Executive summary:

The biodegradation of trichlooctylstannane was determined under "Manometric Respirometry Test" in the OECD Guideline 301F for a period of 39 days at an average temperature of 20.5 ºC. The test method is in agreement with the EU Test Guideline C.4 -D. The test fulfilled the conditions of validity given by the guidelines. The study was also carried out in accordance with the OECD principles of Good Laboratory Practices (GLPs).

A maximum degradation of 3.2 % was reached after 18 days of incubation, and the 60 % degradation criterion was not met under the conditions required by OECD Guideline 301F. After 28 days a degradation of 0.9% was noted. Therefore, trichlooctylstannane was considered not to be readily biodegradable.