Methanesulphonyl chloride

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:

from 2nd December 2009 to 30th december 2009

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP study with dated and signed quality assurance inspection statement included.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2010

Report date:

2010

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

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

Deviations:

not specified

Test guideline 2

Qualifier:

according to guideline

Guideline:

EPA OPPTS 835.3110 (Ready Biodegradability)

Deviations:

not specified

Test guideline 3

Qualifier:

according to guideline

Guideline:

EU Method C.4-E (Determination of the "Ready" Biodegradability - Closed Bottle Test)

Deviations:

not specified

Test guideline 4

Qualifier:

according to guideline

Guideline:

other: Commission Regulation (EC) n. 440/2008 of 30 May lying down methods pursuant to regulation (EC) n. 1907/2006

Deviations:

not specified

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Methanesulphonyl chloride

EC Number:

204-706-1

EC Name:

Methanesulphonyl chloride

Cas Number:

124-63-0

Molecular formula:

CH3ClO2S

IUPAC Name:

methanesulfonyl chloride

Details on test material:

Chemica name: methanesulfonyl chloride (MSC)
batch n. 096260041
Molecular formula: CH3SO2Cl
Molecular weight: 114.55 g/mol
Purity: 99.8%
Appaerance: water white to light yellow liquid
date of production: July 2009
Expiry date: july 2011
Storage condition: room temeperature 15-25°C (humidity ca.50%) and protect by light.

Study design

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, domestic, adapted

Details on inoculum:

The inoculum: Activated sludge, microorganisms from a domestic waste water treatment plant.

Origin: The activated sludge was supplied from the sewage plant for domestic sewage in Veszprém, Hungary.

Conditioning: The activated sludge used for this study was washed by centrifugation (for 10 min.) and the supernatant liquid phase was decanted. The solid material was re-suspended in isotonic saline solution and again centrifuged (for 10 min.). This procedure was repeated twice. An aliquot of the final sludge suspension was weighed, dried and the ratio of wet sludge to its dry weight was determined. Based on this ratio, calculated aliquots of washed sludge suspension, corresponding to 4 g dry material per litre were mixed with test water (see below) and then aerated until use. Before use the sludge was filtered through cotton wool.

Duration of test (contact time):

28 d

Initial test substance concentration

Initial conc.:

8 mg/L

Based on:

other: ThOD(NO3) of 0.56 O2/mg test item ( calculated according to equation given in the guidelines) and on the performed 14-d preliminary test.

Parameter followed for biodegradation estimation

Parameter followed for biodegradation estimation:

O2 consumption

Remarks:

the biodegradation was followed by the oxygen uptake of the microorganisms durin exposure.

Details on study design:

The test was carried out in an incubator and controlled environment room (during the formulation and oxygen measuring) at a temperature of 22.2°C according to guideline. The test flasks were placed into an incubator and kept at 21.6-22.8 C, in the dark. The temperature was measured on weekdays during the experiment. The oxygen concentration of test water was 8.6 mg/L at the start of the test. The pH value of the test water was checked prior study start. The pH of the test water was 7.37. The test conditions were measured with suitable instruments and documented in the raw data.

Reference substance

Reference substance:

benzoic acid, sodium salt

Results and discussion

Preliminary study:

It has been conducted a preliminary test as follows:
The concentration level (10.7 mg/L) investigated in the non-GLP preliminary test was chosen based on the ThOD NO3 of 0.56 mg O 2 /mg test item. The respective amount of Methanesulfonyl Chloride was weighed in directly to reach the required test item concentration of 10.7 mg/L. The duration of the preliminary test was 14 days. In the toxicity control containing both, the test item and the reference item, a mean of 38.0 % biodegradation was noted within 14 days and the test item could be assumed to not inhibit (higher than 25 % degradation occurred within 14 days) the activated sludge microorganisms at the examined concentration level of 10.7 mg/L. The percentage biodegradation of Methanesulfonyl Chloride reached a mean of 75.3 % after 14 days based on its ThOD NO3 in the preliminary study. According to the test guidelines the pass level for ready biodegradability is removal of 60 % ThOD NO3 . The concentration of dissolved oxygen resulted a mean of 2.85 mg O 2 /L after 14 days of incubation in the test item flasks (1a and 1b). According to the test guidelines the residual oxygen concentration in the test flasks will not drop below 0.5 mg O 2 /L at any time. Based on these reasons a lower test item contcentration had been required in the main test.

Test performance:

Main test:
Before the preparation of the respective test solutions with Methanesulfonyl Chloride an aqueous stock solution of Methanesulfonyl Chloride with a concentration of 80 mg/L was prepared and diluted accordingly. The test item concentration in the test solutions was 8.0 mg/L. The chosen test item concentration is based on the theoretical oxygen demand (ThOD NO3 ) of 0.56 mg O 2 /mg test item (calculated according to equation given in the guidelines) and on the performed 14-d preliminary test. During the performance of the test, the test solutions were ultrasonicated for < 10 min. to ensure a good dispersion. The components were applied in the amounts/volumes following ratio in the test flasks:

Test Item:
The test item stock solution* corresponding to 27.68 mg of Methanesulfonyl Chloride was mixed into 3.46 litres of aqueous test medium (corresponding to 8.0 mg/L test item, respectively a ThOD NO3 of about 4.48 mg O 2 /L).

Procedure control: sodium benzoate:
The reference substance stock solution** corresponding to 12.096 mg of Sodium benzoate was mixed into 3.36 litres of aqueous test medium (corresponding to 3.6 mg/L reference item, respectively a ThOD NH4 of about 6.012 mg O 2 /L).

Inoculum control:
Only filtered inoculum was added to 3.40 litres of aqueous test medium.
Toxicity control:
Methanesulfonyl Chloride stock solution* (346 mL) and reference item stock solution** (34.6 mL) were mixed into 3.46 litres of aqueous test medium corresponding to 8.0 mg/L test item (ThOD NO3 of 4.48 mg O 2 /L) and 3.6 mg/L reference item (ThOD NH4 of 6.012 mg O 2 /L).
* The concentration of the test item stock solution
** The concentration of the stock solution was: 360 mg/L.

% Degradation

% Degradation 1

Parameter:

% degradation (O2 consumption)

Value:

10.1

Sampling time:

7 d

% Degradation 2

Parameter:

% degradation (O2 consumption)

Value:

70.5

Sampling time:

17 d

% Degradation 3

Parameter:

% degradation (O2 consumption)

Value:

85

Sampling time:

14 d

% Degradation 4

Parameter:

% degradation (O2 consumption)

Value:

88.4

Sampling time:

21 d

% Degradation 5

Parameter:

% degradation (O2 consumption)

Value:

90.6

Sampling time:

28 d

BOD5 / COD results

Results with reference substance:

Percentage degradation at different time intervals during the exposure period of 28 days:

% Degradation Parameter Sampling time
66.7 O2 consumption 7 d
73.3 O2 consumption 14 d
75.8 O2 consumption 17 d

Any other information on results incl. tables

Dissolved Oxygen Concentrations at Different Time Intervals during the Exposure Period of 28 Days:

Treatment	Concentration [mg/L]	Flask N.	Mg O2/L after n days of exposure
			0	7	14	17	21	28
Test item	8.0	1a	8.6	7.0	4.4	3.7	3.4	3.1
		1b	8.5	7.2	4.4	3.5	3.4	3.3
		mean	8.55	7.10	4.40	3.60	3.40	3.20
Reference item	3.6	1a	8.5	3.5	3.1	2.9	2.7	2.3
		1b	8.5	3.5	3.1	2.7	2.4	2.1
		mean	8.50	3.50	3.10	2.55	2.55	2.20
Inoculum control	-	1a	8.7	7.7	7.7	7.5	7.5	7.4
		1b	8.6	7.6	7.6	7.5	7.4	7.3
		mean	8.65	7.65	7.65	7.50	7.45	7.35
Toxicity control	Test item: 8.0 Ref. Item: 3.6	1a	8.5	4.0	2.3	2.0	1.5	1.0
		1b	8.5	3.8	2.4	2.0	1.3	1.9
		mean	8.50	3.90	2.35	2.00	1.40	0.95

Oxygen depletion at different time intervals during the exposure period of 28 days:

Treatment	Concentration [mg/L]	Flask N.	mg O2/L after n days of exposure
			7	14	17	21	28
Test item	8.0	1a	0.60	3.20	3.75	4.00	4.20
		1b	0.30	3.10	3.85	3.90	3.90
Reference item	3.6	1a	4.0	4.40	4.45	4.60	4.90
		1b	4.0	4.40	4.65	4.90	5.10
Toxicity control	Test item: 8.0 Ref. Item: 3.6	1a	3.50	5.20	5.35	5.80	6.20
		1b	3.70	5.10	5.35	6.00	6.30

oxygen depletion : (mt0 - mtx) - (mbo - mbx),

where:

mt0 : oxygen concentration (mg/L) of test group on day 0

mtx: oxygen concentration (mg/L) of test group on day x

mb0: oxygen concentration (mg/L) of inoculum blank on day 0

mbx: oxygen concentration (mg/L) of inoculum blank on day x

BOD at different time intervals during the exposure period of 28 days:

Treatment	Concentration [mg/L]	Flask N.	mg O2/L after n days of exposure
			7	14	17	21	28
Test item	8.0	1a	0.08	0.40	0.47	0.50	0.53
		1b	0.04	0.39	0.48	0.49	0.49
Reference item	3.6	1a	1.11	1.22	1.24	1.28	1.36
		1b	1.11	1.22	1.29	1.36	1.42
Toxicity control	Test item: 8.0 Ref. Item: 3.6	1a	0.30	0.45	0.46	0.50	0.53
		1b	0.32	0.44	0.46	0.52	0.54

BOD = (mg O2 of T.i. and/or R.i– mg O2 of i. control) / (mg T.i. and/or R.i.in flask) = mgO2/mg T.i. and or R.i.

where: T.i. = test item

R.i. = reference item

i.control = inoculum control

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Interpretation of results:

readily biodegradable