Benzamide, N-[[4-[(cyclopropylamino)carbonyl]phenyl]sulfonyl]-2-methoxy-

Biodegradation in water and sediment: simulation tests

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

biodegradation in water: simulation testing on ultimate degradation in surface water

Data waiving:

other justification

Justification for data waiving:

other:

Transformation products:

not measured

Reference 2

Endpoint:

biodegradation in water: sediment simulation testing

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

22 Mar 2004 - 09 Feb 2005

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 308 (Aerobic and Anaerobic Transformation in Aquatic Sediment Systems)

Version / remarks:

2002

Qualifier:

according to guideline

Guideline:

EPA Subdivision N Pesticide Guideline 162-3 (Anaerobic Aquatic Metabolism)

Version / remarks:

1982

GLP compliance:

yes

Radiolabelling:

yes

Oxygen conditions:

anaerobic

Inoculum or test system:

natural water / sediment: freshwater

Details on source and properties of surface water:

- Details on collection (e.g. location, sampling depth, contamination history, procedure): Water and sediment were collected from a pond located in an agricultural use area in Jefferson County, Kansas, USA. No pesticide has been used in the previous five years. The depth of collection was 0 - 15 cm (0 - 6 inches) for both water and sediment.
- Temperature (°C) at time of collection: 9
- pH at time of collection: 7.9
- Electrical conductivity (mmho/cm): 0.44
- Redox potential (mv) in the study initial/final: 93.2 / 116.7
- Oxygen content in the study (initial / final in mg/L): 0.2 / 0.3
- Hardness (mg equiv. CaCO3/L): 138
- Dissolved organic carbon (ppm): 5.7
- Biomass (initial / final given in cells / mL water): 4.6 x 10^6 / 1.2 x 10^6

Details on source and properties of sediment:

- Details on collection (e.g. location, sampling depth, contamination history, procedure): Water and sediment were collected from a pond located in an agricultural use area in Jefferson County, Kansas, USA. No pesticide has been used in the previous five years. The depth of collection was 0 - 15 cm (0 - 6 inches) for both water and sediment.
- Textural class (USDA): silty clay
- Sediment texture (i.e. %sand/silt/clay): 15/44/41
- pH (water / 0.01 M CaCl2): 7.6 / 7.0
- Organic carbon (%): 0.6
- Redox potential (mv) in the study initial/final: 88.8 / 111.4
- CEC (meq/100 g): 27.4
- Bulk density (g/cm³): 1.13
- Biomass (initial / final given in cells / g sediment): 1.8 x 10^8 / 1.5 x 10^8
- Sediment samples sieved: Yes. The sediment was sieved under water through a 2 mm sieve.

Duration of test (contact time):

155 d

Initial conc.:

16.5 µg/L

Based on:

test mat.

Remarks:

[methoxybenzoyl-ring-UL-14C]-label

Initial conc.:

16 µg/L

Based on:

test mat.

Remarks:

[sulfonylbenzamide-ring-U-14C]-label

Parameter followed for biodegradation estimation:

radiochem. meas.

test mat. analysis

Details on study design:

- Volume of test solution/treatment: Two parallel test sets were prepared with both 14C-labelled versions of the test item, i.e. methoxybenzoyl and sulfonylbenzamide label. The test system consisted of 50 g sediment (dry weight) and 150 mL supernatant water resulting in a water-to-sediment ration of 3 to 1.
- Solubilising agent: The amount of added organic solvent (acetonitrile) was < 0.1 %.
- Test temperature: 25 ± 0.1 °C
- Continuous darkness: yes
- Other: In addition, extra test vessels indicated for metabolite identification (MID) were treated with a higher amount of 151 or 147 μg of the test item resulting in an initial concentration in water of 161 μg/L or 162 μg/L for the methoxybenzoyl or the sulfonylbenzamide acid label

TEST SYSTEM
- Culturing apparatus: Sediment and water were placed together in a series of 250-ml Erlenmeyer flasks with side arms and attached to a greased double-valve top.
- Number of culture flasks/concentration: 2
- Method used to create anaerobic conditions: Prior to application of the test item, the test vessels were equipped with a glass bubbler containing mineral oil, flushed with nitrogen and acclimated in a nitrogen filled incubator of a period of 19 days to establish anaerobic conditions.
- Test performed in closed system: During incubation, the test systems were kept closed.
- Details of trap for CO2 and volatile organics if used: At each sampling interval test systems were flushed with nitrogen and volatiles were purged and trapped in a series of six glass bubblers consisting of a blank, 25 mL of 2 M potassium hydroxide (KOH), another 25 mL of 2 M KOH, 25 mL of ethylene glycol, 25 mL of 1 M sulfuric acid, and another blank.
- Other: The samples were maintained in the dark in an upright incubator that was continuously purged with nitrogen to ensure anaerobic conditions.

SAMPLING
- Sampling frequency: Duplicate test vessels per radiolabel were sampled 0, 3, 7, 14, 30, 60, 91, 121, and 155 days after treatment of the test item.
- Sample storage before analysis: Water and sediment extracts were analyzed within four days after sampling.
- Other: Prior to the separation of sediment and water, 14CO2 and volatile organics were purged from the headspace with stream of nitrogen (30 mL/min for 30 min) and collected from each sample using volatile traps.

Compartment:

natural water / sediment: freshwater

% Total extractable:

83.5

% Non extractable:

2.5

% CO2:

1.7

% Other volatiles:

0

% Recovery:

87.7

St. dev.:

1.2

Remarks on result:

other:

Remarks:

Recovered radioactivity after 155 days; [methoxybenzoyl-ring-UL-14C]-label

Compartment:

natural water / sediment: freshwater

% Total extractable:

97.7

% Non extractable:

1.7

% CO2:

0

% Other volatiles:

0

% Recovery:

99.4

St. dev.:

0.6

Remarks on result:

other:

Remarks:

Recovered radioactivity after 155 days; [sulfonylbenzamide-ring-U-14C]-label

Parent/product:

parent

Compartment:

total system

% Degr.:

1.7

St. dev.:

0.1

Parameter:

radiochem. meas.

Sampling time:

155 d

Remarks on result:

other:

Remarks:

Mineralisation of cyprosulfamide; [methoxybenzoyl-ring-UL-14C]-label

Parent/product:

parent

Compartment:

total system

% Degr.:

0

St. dev.:

0

Parameter:

radiochem. meas.

Sampling time:

155 d

Remarks on result:

other:

Remarks:

Mineralisation of cyprosulfamide; [sulfonylbenzamide-ring-U-14C]-label

Compartment:

natural water: freshwater

DT50:

136 d

Type:

(pseudo-)first order (= half-life)

Temp.:

25 °C

Remarks on result:

other:

Remarks:

Dissipation from the water body; [methoxybenzoyl-ring-UL-14C]-label

Compartment:

natural water: freshwater

DT50:

133 d

Type:

(pseudo-)first order (= half-life)

Temp.:

25 °C

Remarks on result:

other:

Remarks:

Dissipation from the water body; [sulfonylbenzamide-ring-U-14C]-label

Compartment:

natural water: freshwater

DT50:

452.8 d

Type:

(pseudo-)first order (= half-life)

Temp.:

12 °C

Remarks on result:

other:

Remarks:

Dissipation from the water body; [methoxybenzoyl-ring-UL-14C]-label, recalculated to 12 °C

Compartment:

natural water: freshwater

DT50:

442.8 d

Type:

(pseudo-)first order (= half-life)

Temp.:

12 °C

Remarks on result:

other:

Remarks:

Dissipation from the water body; [sulfonylbenzamide-ring-U-14C]-label, recalculated to 12 °C

Compartment:

natural water / sediment: freshwater

DT50:

200 d

Type:

(pseudo-)first order (= half-life)

Temp.:

25 °C

Remarks on result:

other:

Remarks:

Degradation in the entire water-sediment system; [methoxybenzoyl-ring-UL-14C]-label

Compartment:

natural water / sediment: freshwater

DT50:

198 d

Type:

(pseudo-)first order (= half-life)

Temp.:

25 °C

Remarks on result:

other:

Remarks:

Degradation in the entire water-sediment system; [sulfonylbenzamide-ring-U-14C]-label

Compartment:

natural water / sediment: freshwater

DT50:

665.9 d

Type:

(pseudo-)first order (= half-life)

Temp.:

12 °C

Remarks on result:

other:

Remarks:

Degradation in the entire water-sediment system; [methoxybenzoyl-ring-UL-14C]-label, recalculated to 12 °C

Compartment:

natural water / sediment: freshwater

DT50:

659.2 d

Type:

(pseudo-)first order (= half-life)

Temp.:

12 °C

Remarks on result:

other:

Remarks:

Degradation in the entire water-sediment system; [sulfonylbenzamide-ring-U-14C]-label, recalculated to 12 °C

Transformation products:

yes

No.:

#1

No.:

#2

Evaporation of parent compound:

no

Volatile metabolites:

no

Residues:

yes

Details on results:

TEST CONDITIONS
- Anaerobicity, moisture, temperature and other experimental conditions maintained throughout the study: Yes. On the 16th day of the pre-incubation phase (3 days prior to treating test systems), the mean redox potential (Eh) of the water and sediment amounted to 108 mV and 105 mV, respectively (Eh < 200 mV is regarded as anaerobic condition1). The mean dissolved oxygen content in the water was 0.2 mg/L, thus indicating an anaerobic environment had been established prior to treating2. During the entire incubation period Eh in water and sediment was < 152 mV and the dissolved oxygen concentration remained low (≤ 0.6 mg/L) demonstrating that anaerobic conditions had been maintained. The samples were maintained in the dark at 25 ± 1°C. The microbial biomass in water and sediment remained relatively constant throughout the incubation period. The pH of control systems remained relatively stable, ranging from 6.7 - 7.9.

MAJOR TRANSFORMATION PRODUCTS
- Range of maximum concentrations in % of the applied amount and day(s) of incubation when observed:
[methoxybenzoyl-ring-UL-14C]-label: The major degradation product detected in the water was AE 0001789-desmethyl (AE 1448796). The first time it appeared at day 91 with 9.4 % of AR and continuously increased to 13.9 % of AR at study termination (day 155).
[sulfonylbenzamide-ring-U-14C]-label: AE 1448796 (AE 0001789-desmethyl) singularly appeared in the water body at day 7 (1.8 % of AR) and then was not detected until day 91 (9.1 % of AR). It continuously increased until the end of incubation to a level of 12.6 % of AR. In the sediment, it also appeared from day 91 onwards and remained at a constant level of 4.3 – 5.5 % of AR. AE 0852999 (AE 0001789-cyclopropyl-sulfamoylbenzamide) appeared first time in the water at day 14 (0.9 % of AR) and slightly increased until study termination (day 155) to 6.7 % of AR. In the sediment, it first time appeared also at day 14 (0.5 % of AR) and peaked at day 121 up to 3.4 % of AR.

MINOR TRANSFORMATION PRODUCTS
- Range of maximum concentrations in % of the applied amount and day(s) of incubation when observed:
[methoxybenzoyl-ring-UL-14C]-label: AE 1448796 (AE 0001789-desmethyl) was also detected in the sediment phase, with also a first appearance at day 91 (4.7 % of AR) and an increase to 6.9 % of AR also at study termination.

TOTAL UNIDENTIFIED RADIOACTIVITY (RANGE) OF APPLIED AMOUNT:
[methoxybenzoyl-ring-UL-14C]-label: The level of non-identified radiolabelled residues was below 5.0 % of AR in the total system. They consisted of 4 components and mainly appeared in the water phase.
[sulfonylbenzamide-ring-U-14C]-label: The level of non-identified radiolabelled residues ranged from 0 to 10.0 % of AR in the total system. Nonidentified residues consisted of 12 components. In the water phase, 9 components with a maximum portion of up to 7.0 % of AR could be detected.

MINERALISATION
- % of applied radioactivity present as CO2 at end of study:
[methoxybenzoyl-ring-UL-14C]-label: At the end of the study, 1.7% and ≤ 0.1% of AR could be detected as 14CO2 and volatile organic compounds, respectively.
[sulfonylbenzamide-ring-U-14C]-label: At the end of the study, ≤ 0.1% of AR could be detected as 14CO2 or volatile organic compounds, respectively.

Validity criteria fulfilled:

not applicable

Reference 3

Endpoint:

biodegradation in water: sediment simulation testing

Type of information:

experimental study

Adequacy of study:

key study

Study period:

01 Dec 2004 - 12 Oct 2005

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 308 (Aerobic and Anaerobic Transformation in Aquatic Sediment Systems)

Version / remarks:

2002

Qualifier:

according to guideline

Guideline:

EPA Subdivision N Pesticide Guideline 162-4 (Aerobic Aquatic Metabolism)

Version / remarks:

1982

GLP compliance:

yes

Radiolabelling:

yes

Oxygen conditions:

aerobic

Inoculum or test system:

natural water / sediment: freshwater

Details on source and properties of surface water:

- Details on collection (e.g. location, sampling depth, contamination history, procedure): Hönniger Weiher; Wipperfürth, North Rhine Westphalia, Germany (#1); Clayton pond, Johnston County, North Carolina, USA (#2). Both ponds were located in an agricultural area and did not come in contact with pesticides for the previous five years. Water was collected below the surface (0 – 20 cm).
- Storage conditions: Water samples were stored at 4°C until used in the study, acclimatised in the laboratory for 2 - 3 days and, after preparing the individual incubation samples, for an additional period of 12 – 19 days prior to the application of the test item.
- Temperature (°C) at time of collection: 9.2 (#1); 21.0 (#2)
- pH at time of collection: 6.94 (#1); 5.4 (#2)
- Electrical conductivity (mmho/cm): 0.23 (#1); 0.08 (#2)
- Redox potential (mv) at collection site: 283 (#1); 400 (#2)
- Redox potential (mv) in the study initial/final: 307-321 / 254-317 (#1); 340-562 / 432-603 (#2)
- Oxygen concentration (mg/l) initial/final: 6.2-6.5 / 8.0-8.2 (#1); 8.5-8.6 / 8-7-8.8 (#2)
- Hardness (mg equiv. CaCO3): 57 (#1); 9 (#2)
- Dissolved organic carbon (ppm): 6.2 (#1); 3.4 (#2)
- Biomass (initial/final given in cells/mL water): 4.08 x 10^6/4.07 x 10^6 (#1); 6.66 x 10^5/5.51 x 10^5 (#2)

Details on source and properties of sediment:

- Details on collection (e.g. location, sampling depth, contamination history, procedure): Hönniger Weiher; Wipperfürth, North Rhine Westphalia, Germany (#1); Clayton pond, Johnston County, North Carolina, USA (#2). Both ponds were located in an agricultural area and did not come in contact with pesticides for the previous five years. Sediment was collected at a depth of 5 cm.
- Storage length and conditions: Sediment samples were stored at 4°C until used in the study, acclimatised in the laboratory for 2 - 3 days and, after preparing the individual incubation samples, for an additional period of 12 – 19 days prior to the application of the test item.
- Textural class (USDA): silt loam (#1); sandy clay loam (#2)
- Sediment texture (i.e. %sand/silt/clay): 27/60/13 (#1); 75/4/21 (#2)
- Organic carbon at the study end (%): 5.5 (#1); 0.6 (#2)
- CEC (meq/100 g): 11.0 (#1); 4.3 (#2)
- Biomass (initial/final given in cells/g sediment): 3.74 x 10^8/2.56 x 10^8 (#1); 1.14 x 10^8/7.43 x 10^7 (#2)
- Sediment samples sieved: Yes. The sediment was wet sieved through a 2 mm sieve.

Duration of test (contact time):

132 d

Initial conc.:

85.8 µg/L

Based on:

test mat.

Remarks:

[methoxybenzoyl-ring-UL-14C]-label; Hönniger system (#1)

Initial conc.:

86.8 µg/L

Based on:

test mat.

Remarks:

[sulfonylbenzamide-ring-U-14C]-label; Hönniger system (#1)

Initial conc.:

132 µg/L

Based on:

test mat.

Remarks:

[methoxybenzoyl-ring-UL-14C]-label; Clayton system (#2)

Initial conc.:

141 µg/L

Based on:

test mat.

Remarks:

[sulfonylbenzamide-ring-U-14C]-label; Clayton system (#2)

Parameter followed for biodegradation estimation:

radiochem. meas.

test mat. analysis

Details on study design:

TEST CONDITIONS
- Volume of test solution/treatment: 325 mL (#1); 225 mL(#2)
- Solubilising agent: The portion of the organic solvent acetonitrile (originating from the application solution) did not exceed 0.1 % of the water volume.
- Test temperature: 20.3 ± 0.4 °C
- Continuous darkness: yes

TEST SYSTEM
- Culturing apparatus: 500 mL silanized, cylindrical glass flasks (height 12 cm, internal diameter 7.2 cm)
- Number of culture flasks/concentration: 2
- Method used to control oxygen conditions: Each test flask was connected with an inlet tube for supplying humidified air at a flow rate of approximately 10 - 20 mL/min.
- Details of trap for CO2 and volatile organics if used: The air exiting the flask passed sequentially through an ethylene glycol trap (30 mL; #1 Hönniger system only) used for trapping volatile organic compounds, followed by an ethanolamine trap (30 mL; #1 Hönniger and #2 Clayton systems) used for trapping 14CO2.
- Other: The height of the sediment layer was 2 - 3 cm, the height of the supernatant water column 6 - 8 cm. The water-to-sediment ratio was adjusted to approximately 3/1 (v/v) corresponding to 325 mL water and 138 g wet mass (45.5 g dry mass) sediment for the Hönniger system (#1) or 225 mL water and 128 g wet mass (81.4 g dry mass) sediment for the Clayton system (#2).

SAMPLING
- Sampling frequency: Duplicate test systems were sampled after the incubation intervals 0, 1, 20, 47, 70, 97, and 132 days from the Hönniger system (#1) and 0, 8, 21, 48, 78, 104 and 132 from the Clayton system (#2).
- Sampling method used per analysis type: At each sampling interval the pH, concentration of dissolved oxygen and redox potential was measured in the supernatant water. The redox potential was also determined in the sediment phase. Water and sediment was separated by decantation and filtration using a 200-μm glass fibre filter. In addition, the radioactivity in the traps for absorption of organic volatiles (only in Hönniger samples) and 14CO2 as well as the biomass also was determined at each sampling interval.
- Sample storage before analysis: Samples were processed and sediment was extracted on the day of sampling. The maximum storage time of a water sample or sediment extract before chromatographic analysis was 56 days. The majority of water samples and sediment extracts were analyzed within 8 days. The water samples and extracts were stored in a laboratory freezer below -15 °C until analysis.

Compartment:

natural water / sediment: freshwater

% Total extractable:

76.9

% Non extractable:

9.5

% CO2:

6

% Other volatiles:

0

% Recovery:

92.4

St. dev.:

0.9

Remarks on result:

other:

Remarks:

Recovered radioactivity after 132 days; [methoxybenzoyl-ring-UL-14C]-label; Hönniger system (#1)

Compartment:

natural water / sediment: freshwater

% Total extractable:

86.1

% Non extractable:

7.1

% CO2:

3.3

% Other volatiles:

0

% Recovery:

96.4

St. dev.:

0.7

Remarks on result:

other:

Remarks:

Recovered radioactivity after 132 days; [sulfonylbenzamide-ring-U-14C]-label; Hönniger system (#1)

Compartment:

natural water / sediment: freshwater

% Total extractable:

29.1

% Non extractable:

28.6

% CO2:

24.5

% Other volatiles:

0

% Recovery:

82.2

St. dev.:

6.8

Remarks on result:

other:

Remarks:

Recovered radioactivity after 132 days; [methoxybenzoyl-ring-UL-14C]-label; Clayton system (#2)

Compartment:

natural water / sediment: freshwater

% Total extractable:

51.9

% Non extractable:

26.1

% CO2:

13.9

% Other volatiles:

0

% Recovery:

91.8

St. dev.:

5.2

Remarks on result:

other:

Remarks:

Recovered radioactivity after 132 days; [sulfonylbenzamide-ring-U-14C]-label; Clayton system (#2)

Parent/product:

parent

Compartment:

total system

% Degr.:

6

St. dev.:

0.5

Parameter:

radiochem. meas.

Sampling time:

132 d

Remarks on result:

other:

Remarks:

Mineralisation of cyprosulfamide after 132 days; [methoxybenzoyl-ring-UL-14C]-label; Hönniger system (#1)

Parent/product:

parent

Compartment:

total system

% Degr.:

3.3

St. dev.:

0.2

Parameter:

radiochem. meas.

Sampling time:

132 d

Remarks on result:

other:

Remarks:

Mineralisation of cyprosulfamide after 132 days; [sulfonylbenzamide-ring-U-14C]-label; Hönniger system (#1)

Parent/product:

parent

Compartment:

total system

% Degr.:

24.5

St. dev.:

6.2

Parameter:

radiochem. meas.

Sampling time:

132 d

Remarks on result:

other:

Remarks:

Mineralisation of cyprosulfamide after 132 days; [methoxybenzoyl-ring-UL-14C]-label; Clayton system (#2)

Parent/product:

parent

Compartment:

total system

% Degr.:

13.9

St. dev.:

0.7

Parameter:

radiochem. meas.

Sampling time:

132 d

Remarks on result:

other:

Remarks:

Mineralisation of cyprosulfamide after 132 days; [sulfonylbenzamide-ring-U-14C]-label; Clayton system (#2)

Compartment:

natural water: freshwater

DT50:

95.4 d

Type:

(pseudo-)first order (= half-life)

Temp.:

20 °C

Remarks on result:

other:

Remarks:

Dissipation from the water body; Hönniger system (#1)

Compartment:

natural water: freshwater

DT50:

68.1 d

Type:

(pseudo-)first order (= half-life)

Temp.:

20 °C

Remarks on result:

other:

Remarks:

Dissipation from the water body; Clayton system (#2)

Compartment:

natural water: freshwater

DT50:

202.5 d

Type:

(pseudo-)first order (= half-life)

Temp.:

12 °C

Remarks on result:

other:

Remarks:

Dissipation from the water body; Hönniger system (#1); recalculated to 12 °C

Compartment:

natural water: freshwater

DT50:

144.6 d

Type:

(pseudo-)first order (= half-life)

Temp.:

12 °C

Remarks on result:

other:

Remarks:

Dissipation from the water body; Clayton system (#2), recalculated to 12 °C

Compartment:

natural water / sediment: freshwater

DT50:

158 d

Type:

(pseudo-)first order (= half-life)

Temp.:

20 °C

Remarks on result:

other:

Remarks:

Degradation in the entire water-sediment system; Hönniger system (#1)

Compartment:

natural water / sediment: freshwater

DT50:

79 d

Type:

(pseudo-)first order (= half-life)

Temp.:

20 °C

Remarks on result:

other:

Remarks:

Degradation in the entire water-sediment system; Clayton system (#2)

Compartment:

natural water / sediment: freshwater

DT50:

335.4 d

Type:

(pseudo-)first order (= half-life)

Temp.:

12 °C

Remarks on result:

other:

Remarks:

Degradation in the entire water-sediment system; Hönniger system (#1), recalculated to 12 °C

Compartment:

natural water / sediment: freshwater

DT50:

167.7 d

Type:

(pseudo-)first order (= half-life)

Temp.:

12 °C

Remarks on result:

other:

Remarks:

Degradation in the entire water-sediment system; Clayton system (#2), recalculated to 12 °C

Transformation products:

yes

No.:

#1

No.:

#2

No.:

#3

No.:

#4

Evaporation of parent compound:

no

Volatile metabolites:

no

Residues:

yes

Details on results:

TEST CONDITIONS
- Aerobicity (or anaerobicity), moisture, temperature and other experimental conditions maintained throughout the study: Yes. Both sediments were acidic (Hönniger pH 5.8 and Clayton pH 4.1 in a slurry of 0.01 M CaCl2), but the supernatant water was almost neutral (Hönniger pH 7.1 and Clayton pH 7.5). Dissolved oxygen in the water (4.8 – 8.8 mg/L) and the Redox potential (EH) in water and sediment being > 100 mV indicated aerobic conditions for both systems throughout the study. Measurement of the microbial biomass indicated microbial activity for the total incubation period.

MAJOR TRANSFORMATION PRODUCTS
- Range of maximum concentrations in % of the applied amount and day(s) of incubation when observed:
Hönninger system (#1): The formation of AE 0001789-desmethyl (AE 1448796) steadily increased to 8.3 % and 7.6 % of AR by Day 132 (mean of both labels) in the water and sediment phases, respectively. The amount of AE 1448796 in the total system reached 15.8 % of AR at study termination (mean of both labels).
Clayton system (#2): The formation of AE 0001789-cyclopropyl sulfamoylbenzamide (AE 0852999) increased rapidly toward the end reaching maximum quantities of 18.3 %, 5.7 %, and 24.1 % of AR in water, sediment, and total system, respectively, at study termination (sulfonylbenzamide ring label).

MINOR TRANSFORMATION PRODUCTS
- Range of maximum concentrations in % of the applied amount and day(s) of incubation when observed:
Hönninger system (#1): The formation of AE 0001789-descyclopropylamino (AE 0893016) reached an average maximum of 3.5 % of AR in the water phase at Day 97 (mean of both labels) and declined to 3.2 % of AR at termination. In the sediment phase, AE 0893016 did not exceed 1 % of AR. The formation of AE 0001789-cyclopropyl sulfamoylbenzamide (AE 0852999), occurring only in the sulfonylbenzamide label, was low amounting to 5.0 % and 2.5 % of AR in the water and sediment phases, respectively, at Day 97 and to 4.6 % and 3.1% of AR in the water and sediment phases, respectively, at study termination. The formation of AE 0852999 in the total system accounted for 7.8 % of AR at study termination (sulfonamide ring label). AE 0001789-sulfamoylbenzoic acid (AE 0467398), although detectable only in one label, did not exceed 1.2 % of AR in the total system at the end of the experiment (sulfonylbenzamide ring label).
Clayton system (#2): The formation of AE 0001789-descyclopropylamino (AE 0893016), reached a maximum of approx. 9.1 % of AR in the water phase at Day 104 and declined to 3.9% of AR at study termination. In the sediment phase, AE 0893016 steadily increased to 5.3 % of AR by the end of the study (mean of both labels). The formation of AE 0001789-desmethyl (AE 1448796) was minor, not exceeding 3.9 % of AR in either phase or in the total system at any interval (mean of both labels). AE 0001789-sulfamoylbenzoic acid (AE 0467398) reached 5.0 %, 1.7 %, and 6.8 % of AR in water, sediment, and total system, respectively, at the end of the experiment (sulfonamide ring label).

NON-EXTRACTABLE RESIDUES
- % of applied amount at end of study period:
Hönninger system (#1): Non-extractable residues increased from 0.3 % at Day 0 to 9.5 % of AR at Day 132 with the methoxybenzoyl label and and from 0.1 % at Day 0 to 7.5 % of AR at Day 132 with the sulfonylbenzamide label.
Clayton system (#2): Non-extractable residues increased from 0.2 % at Day 0 to 28.6 % of AR at Day 132 with the methoxybenzoyl label and and from 0.2 % at Day 0 to 26.1 % of AE at Day 132 with the sulfonylbenzamide label.

MINERALISATION
- % of applied radioactivity present as CO2 at end of study:
Hönninger system (#1): The amount of 14CO2 increased to 9.5 % with the methoxybenozoyl label and to 7.1 % of AR with the sulfonylbenzamide label at study termination.
Clayton system (#2): The amount of 14CO2 increased to 24.5 % with the methoxybenozoyl label and to 13.9 % of AR with the sulfonylbenzamide label at study termination.

Validity criteria fulfilled:

not applicable

Description of key information

DT50 of parent substance in water/sediment system: 167.7 - 335.4 days at 12 °C (aerob, OECD 308, two water/sediment systems).

 

DT50 of parent substance in water/sediment system: 659.2 - 665.9 days at 12 °C (anaerob, OECD 308, one water/sediment system).

Key value for chemical safety assessment

Half-life in freshwater sediment:

335.4 d

at the temperature of:

12 °C

Additional information

Two GLP studies investigating the transformation of two radiolabels of Cyprosulfamide ([methoxybenzoyl-ring-UL-14C]-label, [sulfonylbenzamide-ring-U-14C]-label) in water/sediment systems under aerobic and anaerobic conditions (OECD 308) are available. The aerobic degradation of radiolabeled Cyprosulfamide was investigated in two different water/sediment systems. Cyprosulfamide dissipated from the water body with a half-life of 68 - 95 days at 20 °C (144.6 - 202.5 days, recalculated to 12 °C). In the entire system, consisting of water and sediment it dissimpated with a half-life of 79 - 158 days (167.7 - 335.4 days, recalculated to 12 °C). The rate of mineralization (formation of 14CO2) reached a maximum 24.5 % AR at the end of the incubation (132 days). After 132 days the two major metabolites 4-(aminosulfonyl)-N-cyclopropylbenzamide and N-cyclopropyl-4-[(2-hydroxybenzoyl) sulfamoyl]benzamide had reached their maximum with 15.8% and 24.1% AR, respectively, in the total system.

Under anaerobic conditions at 25 °C the substance dissipated from the water body with a half-life of 133 - 136 days (442.8 - 452.8 days, recalculated to 12 °C) and from the entire system with a half-life of 198 - 200 days (659.2 - 665.9 days, recalculated to 12 °C). No appreciable volatile components were formed after 155 days, thus no mineralization was detected. Formation of the major metabolites 4-(aminosulfonyl)-N-cyclopropylbenzamide and N-cyclopropyl-4-[(2-hydroxybenzoyl) sulfamoyl]benzamide accounted for up to 6.7% and 13.9% AR, respectively, in the total system at study termination.

 

The available data on biodegradation in water/sediment and soil are sufficient to assess and to conclude on the persistence of Cyprosulfamide. Therefore, a simulation testing on ultimate degradation in surface water (OECD 309), as required by Regulation (EC) No 1907/2006, was deemed scientifically not necessary.