Registration Dossier
Registration Dossier
Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.
The new ECHA CHEM database has been released by ECHA, and it now contains all REACH registration data. There are more details on the transition of ECHA's published data to ECHA CHEM here.
Use of this information is subject to copyright laws and may require the permission of the owner of the information, as described in the ECHA Legal Notice.
EC number: 602-927-1 | CAS number: 123312-89-0
Biodegradation in water and sediment: simulation tests
Administrative data
Link to relevant study record(s)
- Endpoint:
- biodegradation in water and sediment: simulation testing, other
- Remarks:
- natural water/sediment systems (pond and river).
- Type of information:
- experimental study
- Adequacy of study:
- weight of evidence
- Study period:
- 09 Dec 1993 to 18 Apr 1995
- Reliability:
- 1 (reliable without restriction)
- Rationale for reliability incl. deficiencies:
- guideline study
- Qualifier:
- according to guideline
- Guideline:
- other: Richtlinien für die Prüfung von Pflanzenschutzmitteln im Zulassungsverfahren, Teil IV, 5-1, "Abbaubarkeit und Verbleib von Pflanzenschutzmitteln im Wasser/Sediment-System", Biologische Bundesanstalt für Land- und Forstwirtschaft Bundesrepublik Deutschland
- Version / remarks:
- December 1990
- Deviations:
- no
- Qualifier:
- according to guideline
- Guideline:
- EPA Subdivision N Pesticide Guideline 162-4 (Aerobic Aquatic Metabolism)
- Version / remarks:
- October 1982
- Deviations:
- no
- Qualifier:
- according to guideline
- Guideline:
- other: Dutch Registration Guideline, Section G.2: Behaviour in Water; Ministry of Agriculture and Fisheries, Ministry of Public Health and Environmental Hygiene, Ministry of Social Affairs
- Version / remarks:
- January 1987
- Deviations:
- no
- GLP compliance:
- yes
- Radiolabelling:
- yes
- Remarks:
- [14C]-labelled at position 5 of pyridine ring
- Oxygen conditions:
- aerobic
- Inoculum or test system:
- natural water / sediment: freshwater
- Details on source and properties of surface water:
- SOURCE
- River water: Rhine River at Möhlin (AG, Switzerland)
- Pond water: Fröschweiher at Rheinfelden (AG, Switzerland)
PROPERTIES
Origin and properties of the pond and river water are presented in 'Any other information on materials and methods incl. tables'. - Details on source and properties of sediment:
- SOURCE
- River sediment: Same as water
- Pond sediment: Same as water
- Preparation: Before use, the sediments were passed through a 2 mm sieve.
PROPERTIES
Origin and properties of the pond and river sediment are presented in 'Any other information on materials and methods incl. tables'. - Duration of test (contact time):
- 344 d
- Initial conc.:
- 0.9 other: kg/ha
- Based on:
- act. ingr.
- Remarks:
- Normal dose rate
- Initial conc.:
- 9 other: kg/ha
- Based on:
- act. ingr.
- Remarks:
- Exaggerated dose rate
- Parameter followed for biodegradation estimation:
- CO2 evolution
- radiochem. meas.
- Details on study design:
- TEST CONDITIONS
The redox potential (sediment and water), temperature, oxygen concentration and pH were monitored throughout the study and are presented in 'Any other information on materials and methods incl. tables'.
TEST SYSTEM
- Apparatus: An aquatic system consists of a sediment and the corresponding water as a static system. The systems were prepared as follows: Into one-litre all-glass metabolism flasks wet sediment was filled to a height of about 2 cm (98.6 ± 4.0 and 88.1 ± 4.4 g based on sediment dry eight for pond and Rhine, respectively). Afterwards 483 ± 19 ml pond and 458 ± 8 ml Rhine water, respectively, were added to reach a height of about 6 cm. After preparation, the aquatic systems were equilibrated in climatic chambers under aeration with air by gentle stirring from top without disturbing the sediment. During equilibration pH and oxygen content of the water and redox potential of water and sediments were followed. The effluent air was passed through one absorption bottle containing ethylene glycol (50 ml), one absorption bottle containing 0.25 N sulfuric acid (50 ml) and through two absorption bottles each containing 50 ml 2NNaOH.
- Number of samples per treatment: 12 per group for the treated samples; 9 for the untreated biomass samples
- Water volume checks: The water volume was checked in about weekly intervals during the first month and thereafter in about two-weeks intervals. Pure water (bidistilled or adequate quality) was added when necessary.
MICROBIAL BIOMASS MEASUREMENT
The microbial biomass in the sediments was determined by using the respiratory method of Anderson and Domsch, modified for the application on sediments. - Compartment:
- natural water / sediment: freshwater
- % Recovery:
- 93.54
- St. dev.:
- 1.64
- Remarks on result:
- other: mean recovery of applied radioactivity (RA) to the 'pond' water/sediment system.
- Remarks:
- Mean and St.Dev. calculated by registrant.
- Compartment:
- natural water / sediment: freshwater
- % Recovery:
- 94.01
- St. dev.:
- 2.01
- Remarks on result:
- other: mean recovery of applied radioactivity (RA) to the 'river' water/sediment system.
- Compartment:
- natural water: freshwater
- DT50:
- 4.75 d
- Type:
- (pseudo-)first order (= half-life)
- Temp.:
- 20 °C
- Remarks on result:
- other: pond water
- Compartment:
- natural water / sediment: freshwater
- DT50:
- 100.29 d
- Type:
- (pseudo-)first order (= half-life)
- Temp.:
- 20 °C
- Remarks on result:
- other: pond water
- Compartment:
- natural water: freshwater
- DT50:
- 6.29 d
- Type:
- (pseudo-)first order (= half-life)
- Temp.:
- 20 °C
- Remarks on result:
- other: Rhine water
- Compartment:
- natural water / sediment: freshwater
- DT50:
- 143.27 d
- Type:
- (pseudo-)first order (= half-life)
- Temp.:
- 20 °C
- Remarks on result:
- other: Rhine water
- Transformation products:
- yes
- Details on transformation products:
- PATTERN OF METABOLITES
By HPLC two major metabolites (M3 and M1) were found amounting at highest to 2.93 - 4.47 % and 10.77 - 10.88 %. In addition four minor metabolites M2, M5, M6 and M7 were found altogether amounting at highest to 2.36 - 2.74 % of the radioactivity applied. At the end of the study their amounts were 0.62 - 0.82 %. Analysis by two-dimensional TLC gave similar results in respect to the amounts of the parent molecule (test substance) and of the two major metabolites, M3 and M1. In addition to these major radioactive fractions up to eight minor degradates (UK1 - UK8) were observed on twodimensional TLC. With the exception of UK1, UK2 and UK7 at the beginning of the study, these degradates were far below 1 % of the dose applied. However, at the end of the study, these degradates disappeared or were below 1 % of the dose applied. For further identification their amounts were by far too low.
M3
The amount of metabolite M3 in the pond aquatic system was 2.93 % after 120 days and in the Rhine aquatic system 4.47 % after 210 days. At the end of the study M3 amounted to 2.05 % and 2.17 %, respectively. When related to the fresh weight sediment (about 224 g pond and about 221 g Rhine sediment), its amounts corresponded to 0.01312 (pond) and 0.014 mg/ kg (Rhine).
M1
According to HPLC analysis, M1 reached its maximum amount after 28 d with 10. 77 % in the pond aquatic system (Group 1, pond) and after 60 d with 10.88 % in the Rhine aquatic system (Group 2, Rhine). At the end of the studies its concentration had decreased to 2.21 % and 2.48 % of the radioactivity applied, respectively. - Evaporation of parent compound:
- no
- Volatile metabolites:
- yes
- Remarks:
- Volatiles other than 14C-CO2 were detected in an amount of 0.16 % in maximum (see 'Any other information on results incl. tables').
- Residues:
- yes
- Remarks:
- about 17 % of the radioactivity applied (see 'Any other information on results incl. tables').
- Details on results:
- Results are summarised in 'Any other information on results incl. tables'
RADIOACTIVITY IN WATER
In the water the radioactivity steadily decreased within 344 days, reaching 1.31 % (Group 1, pond) and 1.46 % (Group 2, Rhine)
EXTRACTABILITY OF SEDIMENTS
The extractable radioactivity in the sediments steadily increased reaching after 14 - 28 days a maximum of 60.57 - 70.77 %. At the end of the study (344 days) 40.34% (Group 1, pond) and 35.36% (Group 2, Rhine) of the radioactivity applied were reached, respectively. The non-extractable fraction also increased in the corresponding samples up to 21.18 % and 23.21 % of the radioactivity applied.
HARSH EXTRACTION OF POND SEDIMENT (GROUP 1; 344 DAYS)
The harsh extraction of a selected sediment sample from Group 1, pond with acetonitrile / water removed 2.62 - 2.81 % of the radioactivity applied. HPLC-analysis showed, that the majority of the radioactivity consisted of the test substance (70.9 %) and M3 (18.0 %). Extraction with acetonitrile / 0.1 N HCl gave a similar but lower result, as 1.42 % of the radioactivity applied were removed. HPLC-analysis showed, that the majority of the radioactivity again was represented by the test substance (74.6 %) and M3 (19.7 %). Extraction with acetonitrile / 0.1 N NH4OH gave a similar result, as 1.89 % of the radioactivity applied were removed. HPLC-analysis showed, that the majority of the radioactivity again consisted of the test substance (61.1 %) and M3 (16.4 %). In conclusion, about 20 % of the non-extractable fraction (4.2 - 4.5 % of the radioactivity applied) was removed by harsh extraction procedures. The rest remained unextracted (about 17 % of the radioactivity applied) and is hence considered to represent bound residue. The nature of the liberated radioactivity was mainly parent molecule and M3.
CO2 EVOLUTION
After 344 days, the amount of 14C-CO2 evolved was 28.56 % (Group 1, pond) and 32.12 % (Group 2, Rhine), respectively.
DISSAPPEARANCE OF THE TEST SUBSTANCE FROM AQUATIC WATER
The DT50-values observed for test substance were calculated to be 4.8 d and 6.3 d for pond and Rhine water, respectively; the corresponding DT90-values were 30.7 d (Group 1, pond) and 32.6 d (Group 2, Rhine).
DEGRADATION OF THE TEST SUBSTANCE FROM AQUATIC SYSTEMS
Under aerobic conditions at 20°C half-lives of 100.3 and 143.3 days were observed in the pond and Rhine river aquatic system, respectively. The corresponding DT90-values were 1272 d (Group 1, pond) and 1041 d (Group 2, Rhine). - Validity criteria fulfilled:
- not specified
- Conclusions:
- The study has shown, that the test substance disappeared under aerobic conditions at 20 °C from water with half-lives of 4.8 - 6.3 days. The disappearance time of the test substance in the total aquatic system (water and sediment) was in the range of 100.3 - 143.3 days. Besides the parent molecule mainly two major metabolites (M3 and M1) were observed in water and sediment reaching at highest in the pond aquatic system 2.93 % (M3) and 10.77 % (M1) after 120 and 28 days, respectively. In the Rhine aquatic system the corresponding amounts were 4.47 % (M3) and 10.88 % (M1) after 210 and 60 days, respectively.
- Executive summary:
The biodegradation of the test item in water/sediments systems was investigated in a GLP-compliant study according to BBA part IV, 5-1, EPA Guideline 162-4 and Dutch registration guideline, Section G.2. In this study, the rate and route of degradation of the test substance radiolabelled in the pyridine ring, was investigated in two aquatic sediments and associated overlaying water collected from a river (Rhine at Mohlin) and a pond (Froschweiher at Rheinfelden) locations. Water was treated with the radiolabelled test substance to achieve target concentrations of 0.9 and 9 kg/ha in the water phase (based on the normal application dose rate and exaggerated application dose rate). The systems were incubated under aerobic conditions in the laboratory and maintained at 20°C for up to 344 days. Sediment and water samples were taken for analysis 0, 7, 14, 28, 60, 120,210,285 and 344 days after treatment. Average recovery for the river (Rhine) aquatic system ranged from 91.47 % to 97.72 % of the applied radioactivity (AR). Similarly, average recovery for the pond (Rheinfelden) aquatic system ranged from 91.55 % to 96.12% AR over the course of the 344-day study. The test substance disappeared under aerobic conditions at 20 °C from water with half-lives of 4.8 - 6.3 days. The disappearance time of the test substance in the total aquatic system (water and sediment) was in the range of 100.3 - 143.3 days. The DT50 and DT90 values were determined by applying first order one and two compartment reaction kinetics. The amounts of evolved 14C-CO2 were 28.56 and 32.12 %. Transformation products of radiolabelled test substance was observed in the aquatic aerobic sediment systems as evidenced by HPLC profiling. Metabolites M1 and M3 were identified by HPLC and TLC co-chromatography with authentic reference standards. Besides the parent molecule mainly two major metabolites (M3 and M1) were observed in water and sediment reaching at highest in the pond aquatic system 2.93 % (M3) and 10.77 % (M1) after 120 and 28 days, respectively. In the Rhine aquatic system the corresponding amounts were 4.47 % (M3) and 10.88 % (M1) after 210 and 60 days, respectively.
- Endpoint:
- biodegradation in water and sediment: simulation testing, other
- Remarks:
- natural water/sediment systems (pond and river).
- Type of information:
- experimental study
- Adequacy of study:
- weight of evidence
- Study period:
- 06 Dec 1993 to 14 Feb 1995
- Reliability:
- 1 (reliable without restriction)
- Rationale for reliability incl. deficiencies:
- guideline study
- Qualifier:
- according to guideline
- Guideline:
- other: Richtlinien für die Prüfung von Pflanzenschutzmitteln im Zulassungsverfahren, Teil IV, 5-1, "Abbaubarkeit und Verbleib von Pflanzenschutzmitteln im Wasser/Sediment-System", Biologische Bundesanstalt für Land- und Forstwirtschaft Bundesrepublik Deutschland
- Version / remarks:
- December 1990
- Deviations:
- no
- Qualifier:
- according to guideline
- Guideline:
- EPA Subdivision N Pesticide Guideline 162-4 (Aerobic Aquatic Metabolism)
- Version / remarks:
- October 1982
- Deviations:
- no
- Qualifier:
- according to guideline
- Guideline:
- other: Dutch Registration Guideline, Section G.2: Behaviour in Water; Ministry of Agriculture and Fisheries, Ministry of Public Health and Environmental Hygiene, Ministry of Social Affairs
- Version / remarks:
- January 1987
- Deviations:
- no
- GLP compliance:
- yes
- Radiolabelling:
- yes
- Remarks:
- [14C]-labelled at position 6 of triazine ring
- Oxygen conditions:
- aerobic
- Inoculum or test system:
- natural water / sediment: freshwater
- Remarks:
- pond and river
- Details on source and properties of surface water:
- SOURCE
- River water: Rhine River at Möhlin (AG, Switzerland)
- Pond water: Fröschweiher at Rheinfelden (AG, Switzerland)
PROPERTIES
Origin and properties of the pond and river water are presented in 'Any other information on materials and methods incl. tables'. - Details on source and properties of sediment:
- SOURCE
- River sediment: Same as water
- Pond sediment: Same as water
- Preparation: Before use, the sediments were passed through a 2 mm sieve.
PROPERTIES
Origin and properties of the pond and river sediment are presented in 'Any other information on materials and methods incl. tables'. - Duration of test (contact time):
- 361 d
- Initial conc.:
- 0.9 other: kg/ha
- Based on:
- act. ingr.
- Remarks:
- Low treatment level
- Initial conc.:
- 9 other: kg/ha
- Based on:
- act. ingr.
- Remarks:
- High treatment level
- Parameter followed for biodegradation estimation:
- CO2 evolution
- radiochem. meas.
- Details on study design:
- TEST SYSTEM
- First equilibration: After collection of the sediment and water samples sediments together with the corresponding water were equilibrated at 20°C (Rhine sediment/water: 15 days; pond sediment/water: 4 days). During that time air was gently bubbled through the water phase without disturbing the sediment.
- Preparation of aquatic systems: After the first equilibration, corresponding sediment and water samples were transferred into metabolism flasks. Into one-liter all-glass metabolism flasks wet sediment was filled to a height of about 2 cm (218-256 g and 205-251 g for pond and Rhine, respectively). Afterwards 500 mL pond and Rhine water were added each to the corresponding flask.
- Second equilibration: After preparation, the aquatic systems were equilibrated in climatization chambers under aeration with air by gentle stirring from top without disturbing the sediment (Rhine 51 days, pond 31 days). During equilibration pH and oxygen content of the water and redox potential of water and sediments were followed (see 'Any other information on materials and methods incl. tables').
- Trapping of volatiles: The eflfuent air stream was passed through a trapping system containing one bottle with ethyleneglycol (50 mL), one bottle with 0.25 N H2S04 (50 mL) and two bottles with 2 N NaOH (50 mL each).
- Water volume checks: The water volume was checked in about weekly intervals during the first month and thereafter in about two-weeks intervals. Pure water (bidistilled or adequate quality) was added when necessary.
- Incubation: Each natural sediment/water sample was incubated in climatization chambers at 20° ± 2° C in the dark for up to 361 days. During the incubation the water was gently stirred from the top without disturbing the sediment. During incubation the water volume was controlled in about two weeks intervals.
- Number of samples per treatment: 9 per group for the treated samples. 5 additional samples in the pond sediment/water treatment for the metabolite isolation.
MICROBIAL BIOMASS DETERMINATION
The microbial biomass of the sediments was determined at days 0, 120 and 360 after treatment using the respiratory method of Anderson and Domsch. - Compartment:
- natural water / sediment: freshwater
- % Recovery:
- 100
- St. dev.:
- 2.9
- Remarks on result:
- other: mean recovery of applied radioactivity (RA) to the 'pond' water/sediment system was 105.9%.
- Remarks:
- Mean and St.Dev. calculated by registrant.
- Compartment:
- natural water / sediment: freshwater
- % Recovery:
- 100
- St. dev.:
- 3
- Remarks on result:
- other: mean recovery of applied radioactivity (RA) to the 'river' water/sediment system was 105.7%.
- Remarks:
- Mean and St.Dev. calculated by registrant.
- Compartment:
- natural water / sediment: freshwater
- DT50:
- 40.7 d
- Type:
- other: biphasic (overall)
- Temp.:
- 20 °C
- Remarks on result:
- other: pond water
- Compartment:
- natural water / sediment: freshwater
- DT50:
- 93.3 d
- Type:
- other: biphasic (overall)
- Temp.:
- 20 °C
- Remarks on result:
- other: Rhine water
- Compartment:
- natural water / sediment: freshwater
- DT50:
- 12.4 d
- Type:
- other: biphasic (fast reactions)
- Temp.:
- 20 °C
- Remarks on result:
- other: pond water
- Compartment:
- natural water / sediment: freshwater
- DT50:
- 338.1 d
- Type:
- other: biphasic (slow reactions)
- Temp.:
- 20 °C
- Remarks on result:
- other: pond water
- Compartment:
- natural water / sediment: freshwater
- DT50:
- 27.2 d
- Type:
- other: biphasic (fast reactions)
- Temp.:
- 20 °C
- Remarks on result:
- other: Rhine water
- Compartment:
- natural water / sediment: freshwater
- DT50:
- 378.8 d
- Type:
- other: biphasic (slow reactions)
- Temp.:
- 20 °C
- Remarks on result:
- other: Rhine water
- Compartment:
- natural water: freshwater
- DT50:
- 4.2 d
- Type:
- other: biphasic (overall)
- Temp.:
- 20 °C
- Remarks on result:
- other: Rhine water
- Compartment:
- natural water: freshwater
- DT50:
- 4.6 d
- Type:
- other: biphasic (overall)
- Temp.:
- 20 °C
- Remarks on result:
- other: Pond water
- Transformation products:
- yes
- Details on transformation products:
- FORMATION, DECLINE AND NATURE OF DEGRADATION PRODUCTS
Metabolism of the test substance in aquatic systems of pond and Rhine sediment under aerobic conditions was leading to seven degradation products. Metabolite M4 as the major product formed, reaching up to 17.72 and 12.44% of the totally applied radioactivity in pond and Rhine systems, respectively. The peak level was reached 14 days after treatment in pond systems and after 28 days in Rhine samples. M4 was transient in nature, its degradation half-life was determined to be shorter in pond (k1: 41.5 days; overall: 74.8 days) compared to Rhine samples (k1: 120.3 days; overall: 129.5 days). All other metabolites were formed in significantly smaller quantity, reaching maximally 3.70 and 5.87%. In the final samples analyzed the quantities of the degradation products were in the range of 0.72 through 2.45% in pond samples and between 0.40 and 4.59% in Rhine samples.
PATHWAY OF DEGRADATION OF THE TEST SUBSTANCE IN AQUATIC SYSTEMS
From the structural information and the kinetic data of the present study the pathway was derived for the degradation of the test substance under aerobic conditions in aquatic systems. Thereafter the test substance is primarily degraded by hydroxylation of the methylene group in the triazine ring, leading to metabolite M4. Degradation of M4 proceeded via oxidation of the alcoholic group to the ketone followed by subsequent or simultaneous cleavage of the bridge between the triazine and the pyridine ring to yield metabolite M5 and subsequently metabolite M6. Finally the triazine ring was mineralized to CO2 and bound residues were formed. - Evaporation of parent compound:
- no
- Volatile metabolites:
- yes
- Remarks:
- Volatiles other than 14CO2 were not detected.
- Residues:
- not specified
- Details on results:
- Results are summarised in 'Any other information on results incl. tables'
RECOVERY AND DISTRIBUTION PATTERN OF RADIOACTIVITY
- Recovery: The recoveries ranged between 100.16 and 109.51% for pond samples and between 100.07 and 108.59% for Rhine samples. In the water phases of the pond and Rhine aquatic systems the radioactivity decreased within 361 days to 3.98 and 7.10%, respectively. At the same time 76.26 and 75.06% of the radioactivity remained in the sediments of pond and Rhine aquatic systems.
- Extractables: The extractable portion of the radioactivity in the pond and Rhine sediments (cold extract and soxhlet extract) increased from 0.55 and 1.04% (day 0) within 28 days to 57.25 and 62.55%, respectively. Thereafter the extractability of radioactivity decreased reaching 32.74% in pond and 31.49% in Rhine sediment after 361 days.
- Non-extractables: Non-extractable radioactivity in pond sediments increased from 0.23% (day 0) to 43.31 % after 361 days. In Rhine sediment similar results were achieved. Non-extractable radioactivity was 0.21% at day 0 and 43.27% after 361 days. After cold and soxhlet extraction selected sediments were subjected to harsh extractions.
- Harsh extracts: Radioactivities determined in the harsh extracts did not exceed 2.06% of the applied radioactivity. The recovered radioactive material was not further analyzed due to its low amount.
- Volatiles: Volatile radioactivity in form of 14CO2 increased to 24.66 and 22.89% within 361 days for pond and Rhine aquatic samples, respectively. Volatiles other than 14CO2 were not detected.
DISSIPATION AND DEGRADATION
- Dissipation of the test substance in water: The amount of the test substance decreased very rapidly from the water phase and was 0.33 and 0.36% of the totally applied radioactivity 361 days after treatment. The dissapearance from water was very similar in pond and Rhine systems. The overall dissipation half-life was calculated to be 4.6 and 4.2 days for pond and Rhine, respectively.
- Degradation of the test substance in the aquatic systems: The test substance was rapidly degraded in both aquatic systems, reaching 361 days after treatment 27.64 and 25.08% of the dose in pond and Rhine samples, respectively. Based on the rate constant k1 (fast degradation reactions) a shorter half-life time was calculated for the pond compared to the Rhine system, i.e. 12.4 and 27.2 days for pond and Rhine, respectively. The overall degradation half-life (including all degradation processes) was determined to be 40.7 days in the pond and 93.3 days in Rhine systems. Based on the latter results it can be concluded, that the test compound is faster degraded in the pond system compared to the Rhine system, but its distribution between water and sediment layers is obviously independent from the nature of the aquatic system.
COMPARISON OF THE DEGRADATION OF THE TEST SUBSTANCE IN POND AND RHINE AQUATIC SYSTEMS UNDER AEROBIC CONDITIONS
In both aquatic systems the compound was fast degraded. No differences in the metabolic pathways were determined. The degradation half-life of the test substance was shorter in the pond compared to the Rhine system. The latter difference is assumed to be caused by a higher biological activity present in the pond system. No difference was determined for the dissipation half-life of the test substance from water in both systems. - Validity criteria fulfilled:
- not specified
- Conclusions:
- The test substance rapidly disappeared from the water of both aquatic systems with half-lives between 4.2-4.6 days. In the complete systems, degradation of the parent molecule was rapid at the beginning of the study with primary half-lives of 12.4-27.2 days. Thereafter a much slower degradation of the parent molecule was observed with overall half-lives of 40.7 days in the pond and 93.3 days in the Rhine system.
- Executive summary:
The biodegradation of the test item in water/sediments systems was investigated in a GLP-compliant study according to BBA part IV, 5-1, EPA Guideline 162-4 and Dutch registration guideline, Section G.2. In this study, the rate and route of degradation of the test substance radiolabelled in the triazine ring, was investigated in two aquatic sediments and associated overlaying water collected from a river (Rhine at Mohlin) and a pond (Froschweiher at Rheinfelden) locations. Water was treated with the radiolabelled test substance to achieve target concentrations of 0.9 and 9 kg/ha in the water phase (based on the normal application dose rate and exaggerated application dose rate). The systems were incubated under aerobic conditions in the laboratory and maintained at 20°C for up to 361 days. Sediment and water samples were taken for analysis 0, 7, 14, 28, 60, 120,203, 280 and 361 days after treatment. The recoveries ranged between 100.16 and 109.51% for pond samples and between 100.07 and 108.59% for Rhine samples. The test substance rapidly disappeared from the water of both aquatic systems with half-lives between 4.2-4.6 days. In the complete systems, degradation of the parent molecule was rapid at the beginning of the study with primary half-lives of 12.4-27.2 days. Thereafter a much slower degradation of the parent molecule was observed with overall half-lives of 40.7 days in the pond and 93.3 days in the Rhine system. The DT50 and DT90 values were determined by applying first order one and two compartment reaction kinetics. Volatile radioactivity in form of 14CO2 increased to 24.66 and 22.89% within 361 days for pond and Rhine aquatic samples, respectively. Volatiles other than 14CO2 were not detected. Transformation products of radiolabelled test substance was observed in the aquatic aerobic sediment systems as evidenced by HPLC profiling. Metabolite M1 was the major product formed, reaching up to 17.72 and 12.44% of the totally applied radioactivity in pond and Rhine systems, respectively. All other metabolites were formed in significantly smaller quantity, reaching maximally 3.70 and 5.87%. In the final samples analyzed the quantities of the degradation products were in the range of 0.72 through 2.45% in pond samples and between 0.40 and 4.59% in Rhine samples.
- Endpoint:
- biodegradation in water: sediment simulation testing
- Type of information:
- experimental study
- Adequacy of study:
- supporting study
- Study period:
- 09 Jul 2015 to 19 Oct 2015
- 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:
- April 2002
- Deviations:
- no
- Qualifier:
- according to guideline
- Guideline:
- EPA OPPTS 835.4300 (Aerobic Aquatic Metabolism)
- Version / remarks:
- October 2008
- Deviations:
- no
- Qualifier:
- according to guideline
- Guideline:
- EPA OPPTS 835.4400 (Anaerobic Aquatic Metabolism)
- Version / remarks:
- October 2008
- Deviations:
- no
- Qualifier:
- according to guideline
- Guideline:
- other: European Community Commission Directive 95/36/EC of 14 July 1995 both amending Council Directive 91/414/EEC: Annex I: 7.2.1.3.2 Water-sediment study
- Version / remarks:
- July 1995
- Deviations:
- no
- Qualifier:
- according to guideline
- Guideline:
- other: SETAC-EUROPE Procedures for Assessing the Environmental Fate and Ecotoxicity of Pesticides: Section 8 (Aerobic Aquatic Degradation)
- Deviations:
- no
- GLP compliance:
- yes (incl. QA statement)
- Radiolabelling:
- yes
- Remarks:
- [14C]-labelled at position 6 of triazine ring or position 2 of the pyridine ring
- Oxygen conditions:
- aerobic
- Inoculum or test system:
- natural water / sediment: freshwater
- Details on source and properties of surface water:
- - Details on collection: The study was conducted using a water-sediment system collected from the Weweantic River. The Weweantic River water-sediment system was sampled on 29 May 2015 in Wareham, Massachusetts USA. The water and sediment from the Weweantic River were collected from the “ponded” area of the site using a bucket and subsequently transferred into containers. Full details of the sampling dates and the locations are given 'Any other information on materials and methods incl. tables'. After collection, the water was immediately transported to the laboratory and characterized. Measurements of temperature, dissolved oxygen and pH were recorded.
- Details on source and properties of sediment:
- - Details on collection: Same of water. Full details of the sampling dates and the locations are given 'Any other information on materials and methods incl. tables'. After collection, the sediment was immediately transported to the laboratory and then passed through a 2 mm sieve. The sediment was characterized by Agvise Laboratories, Inc. (Northwood, ND) to determine organic-matter content (from which the organic carbon content was calculated), cation-exchange capacity, pH, bulk density and texture (% sand, %silt and % clay). The Weweantic River sediment was characterized as sand with an organic-carbon content (OC) of 1.1% w/w dry weight. The acclimation period was 20 days.
- Duration of test (contact time):
- 102 d
- Initial conc.:
- 0.034 mg/L
- Based on:
- act. ingr.
- Remarks:
- measured [Triazinyl-14C] test concentration
- Initial conc.:
- 0.035 mg/L
- Based on:
- act. ingr.
- Remarks:
- measured [Pyridinyl-14C] test concentration
- Parameter followed for biodegradation estimation:
- CO2 evolution
- radiochem. meas.
- Details on study design:
- TEST SYSTEM
- Sediment condition: Fresh, < 3 weeks of collection passed through 2 mm sieve and stored refrigerated prior to use.
- Water condition: Fresh, < 3 weeks of collection and stored refrigerated prior to use.
- Sample size (per test vessel) sediment (to give 2.5 cm depth, g dry wt.): approximately 112 g (dry weight)
- Sample size (per test vessel) water (to give 7.5 cm height, mL): approximately 360 mL
- Sediment:Water Ratio: approximately 1:3
- Number of replicates: 2 sampling replicates per radiolabel treatment
- Test apparatus: Glass flask, moist air bubbled through system, connections made with glass and Teflon® tubing
- Incubation conditions Aerobic: aerated continuously with ambient hydrated air
- Traps for CO2 & organic volatiles: One ethylene glycol (organic volatiles) trap and two 2M NaOH traps for 14CO2 on one trapping train per radiolabel treatment Sampled starting at 4 DAT
- Temperature (°C): 20 ± 2
- Complete darkness: Yes
- Preparations: Aliquots of the appropriate sediment were dispensed into pre-labeled 500-mL glass screw cap vessels with Teflon®-lined silicone septa to a depth of 2.5 cm. With minimum disturbance, the associated surface water was added to a depth of 7.5 cm above the sediment surface. Ratios of approximately 1:3 (based upon sediment: water depth) were obtained for all samples of both systems. The dry weight was determined for each radiolabeled test system at the time of dispensing.
PREPARATION OF TREATMENT SOLUTIONS
- [Triazinyl-6-14C]-test substance: A primary radiolabeled stock solution was prepared by quantitatively transferring the entire amount of test substance to a volumetric flask and diluting to 25 mL with acetonitrile. Triplicate 5-μL aliquots of the stock solution were then assayed by LSC. Based on this analysis and the specific activity of 61.0 μCi/mg (135420 dpm/μg), the stock solution was determined to have a concentration of 0.665 mg/mL upon preparation. Prior to use, triplicate 5-μL aliquots of the stock solution were reassayed by LSC and the stock solution was determined to have a concentration of 0.630 mg/mL. The stock was stored in a freezer in an amber Wheaton bottle fitted with a Teflon®-lined septum until use.
- [Pyridinyl-2-14C]-test substance: A primary radiolabeled stock solution was prepared by quantitatively transferring the entire amount of test substance to a volumetric flask and diluting to 25 mL with acetonitrile. Triplicate 5-μL aliquots of the stock solution were then assayed by LSC. Based on this analysis and the Study Sponsor supplied specific activity of 58.9 μCi/mg (130758 dpm/μg), the stock solution was determined to have a concentration of 0.742 mg/mL upon preparation. Prior to use, triplicate 5-μL aliquots of the stock solution were reassayed by LSC and the stock solution was determined to have a concentration of 0.716 mg/mL. The stock was stored in a freezer in an amber Wheaton bottle fitted with a Teflon®-lined septum until use.
APPLICATION
Before dosing, the sediment and water system was allowed to equilibrate to laboratory conditions for 20 days. The [triazinyl-6-14C]-test substance water-sediment test system was dosed using 21 μL of the [triazinyl-6-14C]-test substance stock solution (equating to 1,644,519 dpm test substance). The [pyridinyl-2-14C]-test substance water-sediment test system was dosed using 18 μL of the [pyridinyl-2-14C]-test substance stock solution (equating to 1,634,552 dpm test substance). The dosing solution was incorporated into the water phase to obtain a final concentration of approximately 0.034 and 0.035 μg/mL for the [triazinyl-6-14C]-test substance and [pyridinyl-2-14C]-test substance test systems, respectively. The homogeneity and stability of the [triazinyl-6-14C]-test substance and [pyridinyl-2-14C]-test substance dosing solutions were confirmed by LSC and HPLC/RAM before and after dosing.
MICROBIAL BIOMASS DETERMINATION
The microbial biomass of the sediment was determined by fumigation/extraction (Brookes et al., 1990) prior to test initiation (post-handling/pretreatment), at test initiation and at test termination. Triplicate sediment samples were fumigated with chloroform to lyse the microbial biomass and release soluble organic carbon. Both fumigated and non-fumigated sediments were subjected to organic carbon extraction using 0.5 M potassium sulfate (K2SO4) and the total extractable organic carbon (TOC) was measured with a carbon analyzer. The difference in TOC values between fumigated and non-fumigated sediments represented the organic carbon from biomass.
TEST SYSTEM QUALITY MEASUREMENTS
Prior to use, the percent moisture of the Weweantic River sediment was determined using a Sartorius moisture balance to be 33.1% (w/w, wet-weight basis). Test system parameters, including pH (water and sediment), dissolved oxygen (water) and redox potential (water and sediment) were measured at sediment acclimation, at the middle of the study and the end of the study. This data is provided in 'Any other information on materials and methods incl. tables' - Compartment:
- natural water / sediment: freshwater
- % Recovery:
- 98.2
- St. dev.:
- 5.7
- Remarks on result:
- other: [Triazinyl-6-14C]-test substance recovery
- Compartment:
- natural water / sediment: freshwater
- % Recovery:
- 98.2
- St. dev.:
- 7.4
- Remarks on result:
- other: [Pyridinyl-6-14C]-test substance recovery
- Compartment:
- natural water / sediment: freshwater
- DT50:
- 13 d
- Type:
- (pseudo-)first order (= half-life)
- Temp.:
- 20 °C
- Remarks on result:
- other: Total system
- Remarks:
- [Triazinyl-14C]-labelled test substance
- Compartment:
- natural water / sediment: freshwater
- DT50:
- 7.6 d
- Type:
- (pseudo-)first order (= half-life)
- Temp.:
- 20 °C
- Remarks on result:
- other:
- Remarks:
- [Pyridinyl-14C]-labelled test substance
- Compartment:
- natural water: freshwater
- DT50:
- 3.6 d
- Type:
- (pseudo-)first order (= half-life)
- Temp.:
- 20 °C
- Remarks on result:
- other: Water phase
- Remarks:
- [Triazinyl-14C]-labelled test substance
- Compartment:
- natural water: freshwater
- DT50:
- 4 d
- Type:
- (pseudo-)first order (= half-life)
- Temp.:
- 20 °C
- Remarks on result:
- other: Water phase
- Remarks:
- [Pyridinyl-14C]-labelled test substance
- Transformation products:
- yes
- Details on transformation products:
- RADIAOCTIVE RESIDUES IN WATER PHASE
Aliquots of water were analyzed directly by LSC. Levels of parent compound in the water phase decreased over the 102 day incubation period. M1 was a major metabolite (10.9% AR in one sample on 7 DAT), reaching average maximum average levels of 5.4 and 4.5% AR at 7 DAT in the [triazinyl-6-14C]-test substance and [pyridinyl-2-14C]-test substance test systems, respectively. A polar transformation product (M5) was also present at an average of 6.3% AR at 61 DAT in the [triazinyl-6-14C]-test substance test system. Several minor transformation products were observed. However, these individual peaks were observed to be < 5% AR in both test systems and were not considered any further.
RADIAOCTIVE RESIDUES IN SEDIMENT EXTRACTS
The level of parent compound in the sediment increased to maximum values at 7 DAT for both test systems (31.3% AR and 27.7% AR for the [triazinyl-6-14C]-test substance and [pyridinyl-2-14C]-test substance test systems, respectively). Thereafter, the percent of applied radioactivity present as the radiolabelled test substance generally decreased throughout the remainder of the 102-day incubation period. No individual transformation products were present at ≥ 5% AR in the sediment phase of either test system. Several minor transformation products, including M1 and M5, were observed. However, these individual peaks were observed to be < 5% AR in both test systems and were not considered any further.
Several minor regions of radioactivity were observed during testing; each was observed at < 5% AR in all phases (water and extracts) and not considered further. There were no unknown degradates formed in this study.
PROPOSED PATHWAY
In the water-sediment system for both labels, during the aerobic phase, the major degradates were M1 and a polar metabolite, M5. The test substance underwent hydroxylation and oxidation and C-N bond cleavage to form these metabolites. Mineralization was a major route of aerobic degradation (CO2 accounted for 18.6 and 50.9% AR, respectively for the [triazinyl-6-14C] and [pyridinyl-2-14C]-test substance test systems) with a minor amount (< 0.4% AR) of volatile organics. - Evaporation of parent compound:
- no
- Volatile metabolites:
- yes
- Remarks:
- see 'Details on results'
- Residues:
- yes
- Remarks:
- see 'Details on results'
- Details on results:
- MICROBIAL BIOMASS
The microbial biomass carbon was approximately 6.2 mg C/100 g sediment (0.52% OC) at the time of treatment, which indicates the sediment supported a viable microbial population and that the sediment was suitable for use in a laboratory degradation study. The microbial biomass carbon was 2.1 mg C/100 g sediment (0.19% OC) after the 102 DAT incubation period.
VOLATILE DEGRADATION PRODUCTS
Radioactivity recovered as evolved 14CO2 was high, reaching 18.6 and 50.9% AR for the [triazinyl-6-14C]-test substance and [pyridinyl-2-14C]-test substance test systems, respectively, by the end of the experiment. At 61 DAT mass balance was low for the pyridinyl labeled samples due to low radioactivity (10.9% AR) measured from the individual 14CO2 traps. Since these values were greater at both 32 DAT and 76 DAT the reduced mass balance for this label suggests a leak in the trapping train system occurred at 61 DAT.
- 14CO2 (triazinyl label) evolved at end of study: Mean 17.7% M
- 14CO2 (pyridinyl label) evolved at end of study: Mean 48.8% AR
- Ethylene glycol traps (triazinyl label):
WATER EXTRACTABLES
- Total water residues at 0 DAT (triazinyl label): Mean 95.8%
- Total water residues at 0 DAT (pyridinyl label): Mean 99.1%
- Total water residues at end of study (triazinyl label): Mean 7.1%
- Total water residues at end of study (pyridinyl label): Mean 0.5%
EXTRACTABLE RESIDUES (including radioactivity in water phase)
- Total extractable residues at 0 DAT (triazinyl label): Mean 97.0%
- Total extractable residues at 0 DAT (pyridinyl label): Mean 100.4%
- Total extractable residues at end of study (triazinyl label): Mean 16.1%
- Total extractable residues at end of study (pyridinyl label): Mean 5.9%
UNEXTRACTED (BOUND) RESIDUES
Unextracted residues generally increased throughout the incubation, reaching a maximum of 58.6 and 48.6% AR by 61 and 32 DAT, for the water-sediment systems treated with [triazinyl-6-14C]-test substance and [pyridinyl-2-14C]-test substance.
- Bound residues at start of study (triazinyl label): Mean 0.8%
- Bound residues at start of study (pyridinyl label): Mean 1.5%
- Bound residues at end of study (triazinyl label): Mean 52.6%
- Bound residues at end of study (pyridinyl label): Mean 30.5% - Validity criteria fulfilled:
- not specified
- Conclusions:
- The dissipation rate (DT50) from the water phase using simple first order (SFO) kinetics was 3.8 days for the combined data from the [triazinyl-6-14C]-test substance and [pyridinyl-2-14C]-test substance test systems. Half-life (DegT50) in the total system was 9.5 days for the combined data from the ([triazinyl-6-14C]-test substance treated system) and ([pyridinyl-2-14C]-test substance treated system).
- Executive summary:
DESIGN
The rate and route of degradation of [triazinyl-6-14C]-test substance and [pyridinyl-2-14C]-test substance was investigated under aerobic conditions in one water sediment system collected from the Weweantic River (sand). [Triazinyl-6-14C]-test substance or [pyridinyl-2-14C]-test substance was applied to the water at a nominal rate of 0.036 μg/mL based on the maximum single application rate of 725 g a.i./ha. The water-sediment system for each label was maintained under aerobic conditions. The water-sediment system was incubated in the laboratory and maintained under dark conditions at 20 ± 2 °C for 102 days. Volatile radioactivity was continuously collected in traps throughout the study. Water, sediment and volatile trap samples from each system were analyzed at 0, 1, 4, 7, 14, 32, 61, 76 and 102 days after treatment (DAT). At each sampling interval, the test system was separated into the water and sediment fractions. The sediment fractions were extracted once at ambient temperature, using 200 mL of 80:20 acetonitrile:purified reagent water (v:v) to give Extract 1. Starting on 1 DAT sediment was extracted two additional times with 80:20 acetonitrile:purified reagent water (v:v) to give Extracts 2 and 3. These extracts were considered to represent the bioavailable residues and are here forth referred to as the “extractable” residues. These residues were characterized by high performance liquid chromatography with radiochemical detection (HPLC/RAM) for quantification. Additionally, the sediment extracts were extracted two more times, once using 200 mL of tetrahydrofuran (THF, Extract 4) and once using 200 mL of toluene (Extract 5). These extracts were radioassayed by liquid scintillation counting (LSC). No further characterization of the THF and toluene extracts was performed. A select number of samples were also taken for 2D thin layer chromatography (TLC) characterization. Identification or confirmation against known reference standards of any major (> 5% AR) transformation products was performed by liquid chromatography with mass spectrometry detection (LC/MS). Mass balance was determined for each sample. The water and sediment extracts were radioassayed by LSC and analyzed separately by HPLC/RAM to quantify [14C]- test substance and any transformation products. Additional analyses were performed on selected samples by TLC for confirmation of known compounds using authenticated reference standards.
CONCLUSIONS
Dissipation of the test substance from the water phase was relatively fast in the water-sediment system for both labels under aerobic conditions. Parent compound in the [triazinyl-6-14C]-test substance test system represented a mean of 18.1% AR after 14 days of incubation and was undetected throughout the remainder of the incubation. Parent compound in the [pyridinyl-2-14C]-test substance test system represented a mean of 31.1% AR after 7 days of incubation and was undetected throughout the remainder of the incubation. Levels of the test substance increased in the sediment phase at the start of the study, reaching peak mean levels of 31.3% AR at 7 DAT and 27.7% AR at 7 DAT in the [triazinyl-6-14C]-test substance and [pyridinyl-2-14C]-test substance test systems, respectively, and then declining for the remainder of the study. The dissipation rate (DT50) from the water phase using simple first order (SFO) kinetics was 3.8 days for the combined data from the [triazinyl-6-14C]-test substance and [pyridinyl-2-14C]-test substance test systems. Half-life (DegT50) in the total system was 9.5 days for the combined data from the ([triazinyl-6-14C]-test substance treated system) and ([pyridinyl-2-14C]-test substance treated system). The route of degradation was similar in the water-sediment system for both labels, with M1 being the major degradation product observed. The test substance underwent hydroxylation to form M1. Several other degradation products were observed at low levels in the water-sediment system for both labels, all < 5% of applied in either phase. Unextractable (bound) residues reached mean values of 52.6 and 30.5% AR in the [triazinyl-6-14C]-test substance and [pyridinyl-2-14C]-test substance test systems, respectively, by the end of the study (102 DAT). Mineralization to 14CO2 reached 18.6 and 50.9% AR by the end of the incubation, for the [triazinyl-6-14C]-test substance and [pyridinyl-2-14C]-test substance test systems, respectively.
Referenceopen allclose all
Table: Microbial Biomass of Pond and Rhine Sediment.
Sediment |
Microbial Biomass (mg C / 100 g sediment) |
||
0 days |
118 days |
360 days |
|
Pond |
528.1 |
406.5 |
280.8 |
Rhine |
226.4 |
154.4 |
117.8 |
Table: Distribution Pattern of 14C-Activity for the Degradation of the test substance in Pond Aquatic System (Group 1: aerobic, 20 °C).
(Values given in% of the dose applied.)
Incubation Time (days) |
CO2 |
Volatiles |
Water |
Extractable |
Non- Extractable |
Recovery |
0 |
0.00 |
0.00 |
92.63 |
0.25 |
0.04 |
92.91 |
7 |
0.13 |
0.00 |
38.63 |
50.25 |
6.70 |
95.71 |
14 |
0.72 |
0.00 |
24.23 |
60.57 |
10.60 |
96.12 |
28 |
3.63 |
0.00 |
16.56 |
59.50 |
15.03 |
94.72 |
60 |
12.34 |
0.00 |
6.72 |
56.86 |
17.17 |
93.09 |
120 |
20.97 |
0.01 |
4.02 |
48.61 |
19.93 |
93.54 |
210 |
25.38 |
0.02 |
2.42 |
43.61 |
20.75 |
92.18 |
285 |
36.30 |
0.01 |
1.73 |
31.32 |
22.66 |
92.02 |
344 |
28.56 |
0.16 |
1.31 |
40.34 |
21.18 |
91.55 |
Table: Distribution Pattern of 14C-Activity for the Degradation of the test substance in Rhine Aquatic System (Group 2: aerobic, 20 °C).
(Values given in% of the dose applied.)
Incubation Time (days) |
CO2 |
Volatiles |
Water |
Extractable |
Non- Extractable |
Recovery |
0 |
0.00 |
0.00 |
93.08 |
1.30 |
0.03 |
94.41 |
7 |
0.17 |
0.00 |
43.80 |
48.50 |
3.44 |
95.92 |
14 |
0.50 |
0.00 |
28.33 |
59.87 |
5.27 |
93.97 |
28 |
2.08 |
0.00 |
14.45 |
70.77 |
10.42 |
97.72 |
60 |
7.08 |
0.01 |
9.54 |
64.97 |
12.76 |
94.36 |
120 |
17.66 |
0.00 |
4.94 |
51.57 |
17.66 |
91.83 |
210 |
24.19 |
0.01 |
2.66 |
45.89 |
21.42 |
94.18 |
285 |
33.78 |
0.03 |
1.78 |
34.47 |
21.41 |
91.47 |
344 |
32.12 |
0.02 |
1.46 |
35.36 |
23.21 |
92.19 |
Table: Distribution of radiolabelled test substance and Metabolites in Pond Aquatic System (Group 1: aerobic, 20 °C): Comparison HPLC with TLC.
(Values given in% of the 14C-radioactivity applied)
Incubation time (days) |
28 |
60 |
120 |
210 |
285 |
344 |
||||||
Method |
HPLC |
TLC |
HPLC |
TLC |
HPLC |
TLC |
HPLC |
TLC |
HPLC |
TLC |
HPLC |
TLC |
Test substance |
60.83 |
56.76 |
49.74 |
47.04 |
44.09 |
36.37 |
41.53 |
40.52 |
26.45 |
27.22 |
36.77 |
37.04 |
M3 |
2.72 |
3.61 |
2.76 |
7.89 |
2.93 |
10.47 |
n.d. |
1.20 |
0.97 |
0.85 |
2.05 |
0.54 |
M1 |
10.77 |
10.20 |
9.59 |
4.29 |
5.62 |
2.94 |
3.79 |
2.42 |
5.63 |
4.04 |
2.21 |
3.23 |
n.d. = not determined
Table: Distribution of the radiolabelled test substance and Metabolites in Rhine Aquatic System (Group 2: aerobic, 20 °C): Comparison HPLC with TLC.
(Values given in % of the 14C-radioactivity applied)
Incubation time (days) |
60 |
344 |
||
Method |
HPLC |
TLC |
HPLC |
TLC |
Test substance |
60.96 |
56.10 |
31.35 |
31.80 |
M3 |
1.92 |
9.75 |
2.17 |
0.59 |
M4 |
10.88 |
5.86 |
2.48 |
2.16 |
Table: Disappearance Rate of the radiolabelled test substance from Water and from the total Aquatic System.
Group |
1 |
1 |
2 |
2 |
Incubation Conditions |
Pond water |
Pond system |
Rhine water |
Rhine system |
Parameter |
|
|
|
|
C01 (% parent) |
63.86102 |
39.23002 |
76.98475 |
35.49957 |
k01 (1/days) |
0.21432 |
0.03965 |
0.13252 |
0.01775 |
c02 (% parent) |
25.23691 |
50.68385 |
11.93742 |
53.12274 |
k02 (1/days) |
0.03425 |
0.00136 |
0.01283 |
0.00172 |
DT50 (days) |
4.75 |
100.29 |
6.29 |
143.27 |
DT90 (days) |
30.69 |
1271.57 |
32.55 |
1041.17 |
Chi-squared |
0.91 |
19.90 |
0.53 |
5.97 |
Ct: the concentration of test substance at time t
c01: initial concentration of test substance in compartment 1
k01 : the degradation rate constant in compartment 1
c02: initial concentration of test substance in compartment 2
k02 : the degradation rate constant in compartment 2.
Tables: Harsh Extraction of Bound Residue of Pond Sediment after 344 Days of Incubation.
(Values given in% of radioactivity applied)
Final acidic extraction:
Pond sediment Sample No. |
Incubation Time (days) |
Non-Extractables after Soxhlet-Extraction |
Extraction (acetonitrile / H2O (%) |
Extraction (acetonitrile / 0.1 N HCl) (%) |
Total Harsh Extract (%) |
Residual Bound Residue calc. (%) |
9 |
344 |
21.18 |
2.81 |
1.42 |
4.23 |
16.95 |
Final basic extraction:
Pond sediment Sample No. |
Incubation Time (days) |
Non-Extractables after Soxhlet-Extraction |
Extraction (acetonitrile / H2O (%) |
Extraction (acetonitrile / 0.1 N NH4OH) (%) |
Total Harsh Extract (%) |
Residual Bound Residue calc. (%) |
9 |
344 |
21.18 |
2.62 |
1.89 |
4.51 |
16.67 |
HPLC analysis of harsh extracts (values given are in % of radioactivity injected (ROI)).
Metabolite |
Extraction (acetonitrile / H2O) (%) |
Extraction (acetonitrile / 0.1 N HCl) (%) |
Extraction (acetonitrile / 0.1 N NH4OH) (%) |
Test substance |
70.9 |
74.6 |
61.1 |
M3 |
18.0 |
19.7 |
16.4 |
Table: Microbial biomass results (Pond sediment)
Time [days] |
Biomass [mg/100g dry sediment] |
0 |
422 |
118 |
364 |
360 |
281 |
Mean |
356 |
Table: Microbial biomass results (Rhine sediment)
Time [days] |
Biomass [mg/100g dry sediment] |
0 |
243 |
120 |
135 |
360 |
118 |
Mean |
165 |
Table: Distribution of Radioactivity during Degradation of [6-14C] Triazine labelled test substance in the Pond System
Time |
H2O-Phase |
Sediment-Extract |
Soxhlet |
Combust. |
Total Sediment |
Eth. Gly |
H2SO4 |
NaOH |
Total Volatiles |
Recovery |
[% Applied] |
||||||||||
0 |
99.39 |
0.55 |
0.00 |
0.23 |
0.78 |
0.00 |
0.00 |
0.00 |
0.00 |
100.16 |
7 |
41.12 |
53.47 |
0.19 |
14.70 |
68.37 |
0.00 |
0.00 |
0.03 |
0.03 |
109.51 |
14 |
30.04 |
56.65 |
0.27 |
21.02 |
77.93 |
0.00 |
0.00 |
0.23 |
0.23 |
108.20 |
28 |
21.25 |
57.25 |
0.41 |
26.16 |
83.83 |
0.00 |
0.00 |
1.30 |
1.31 |
106.38 |
60 |
13.57 |
47.24 |
2.72 |
35.98 |
85.94 |
0.00 |
0.00 |
5.58 |
5.58 |
105.08 |
120 |
6.89 |
44.00 |
3.41 |
43.31 |
90.72 |
0.00 |
0.00 |
11.86 |
11.86 |
109.48 |
203 |
5.70 |
31.67 |
0.68 |
46.88 |
79.22 |
0.00 |
0.00 |
20.70 |
20.70 |
105.62 |
280 |
4.17 |
26.70 |
3.16 |
45.52 |
75.38 |
0.00 |
0.00 |
24.54 |
24.54 |
104.09 |
361 |
3.98 |
32.74 |
0.22 |
43.31 |
76.26 |
0.00 |
0.00 |
24.66 |
24.66 |
104.90 |
NaOH: Radioactivity trapped as CO2
Table: Distribution of Radioactivity during Degradation of [6-14C] Triazine labelled CGA 215 44 in the Rhine System
Time |
H2O-Phase |
Sediment-Extract |
Soxhlet |
Combust. |
Total Sediment |
Eth. Gly |
H2SO4 |
NaOH |
Total Volatiles |
Recovery |
[% Applied] |
||||||||||
0 |
98.82 |
1.04 |
0.00 |
0.21 |
1.25 |
0.00 |
0.00 |
0.00 |
0.00 |
100.07 |
7 |
47.79 |
53.96 |
0.15 |
6.56 |
60.67 |
0.00 |
0.00 |
0.05 |
0.05 |
108.51 |
14 |
38.65 |
55.09 |
0.66 |
11.70 |
67.45 |
0.00 |
0.00 |
0.17 |
0.17 |
106.27 |
28 |
24.94 |
62.55 |
0.48 |
19.83 |
82.87 |
0.00 |
0.00 |
0.66 |
0.66 |
108.47 |
60 |
16.15 |
59.12 |
3.21 |
27.53 |
89.86 |
0.00 |
0.00 |
2.58 |
2.58 |
108.59 |
120 |
8.75 |
48.86 |
4.67 |
37.45 |
90.98 |
0.00 |
0.00 |
6.15 |
6.16 |
105.89 |
203 |
9.66 |
38.64 |
1.04 |
40.63 |
80.31 |
0.00 |
0.00 |
16.45 |
16.45 |
106.42 |
280 |
6.74 |
37.91 |
3.56 |
36.75 |
78.22 |
0.00 |
0.00 |
16.85 |
16.85 |
101.80 |
361 |
7.10 |
31.49 |
0.30 |
43.27 |
75.06 |
0.00 |
0.00 |
22.89 |
22.89 |
105.05 |
NaOH: Radioactivity trapped as CO2
Table: Harsh Extraction of selected samples
Sampling Time |
Method A |
Method B |
Total |
[days] |
[% Appl.] |
||
203 |
1.61 |
0.45 |
2.06 |
280 |
0.55 |
0.14 |
0.69 |
203 |
1.59 |
0.47 |
2.06 |
280 |
62 |
0.17 |
0.79 |
Method A) Refluxing soils with acetonitrile / water 4:1 / 1-2 h
Method B) Refluxing soils with acetonitrile / 0.1 mol HCL 9:1 / 1-2 h
Table: Dissipation of the test substance from Water and degradation of the test substance and M4 in the Sediment/Water Systems
|
Degradation of the test substance in the Sediment/Water systems |
Degradation of M4 in the Sediment/Water systems |
Dissipation of the test substance from Water |
|||
Pond |
Rhine |
Pond |
Rhine |
Pond |
Rhine |
|
k1 (per day) |
0.05583 |
0.02545 |
0.01669 |
0.00576 |
0.18432 |
0.89818 |
k2 (per day) |
0.00205 |
0.00183 |
0.00329 |
0.00578 |
0.02004 |
0.04340 |
C01 |
51.6 |
45.4 |
11.4 |
10.0 |
83.9 |
40.1 |
C02 |
47.5 |
52.4 |
7.1 |
3.1 |
14.1 |
56.6 |
Chi-squared |
22.87159 |
11.72276 |
1.45907 |
0.9603 |
0.35559 |
3.98806 |
DT-50(1) (days) |
12.4 |
27.2 |
41.5 |
120.3 |
- |
- |
DT-50(2) (days) |
338.1 |
378.8 |
210.7 |
119.9 |
- |
- |
DT-50ov (days) |
40.7 |
93.3 |
74.8 |
129.5 |
4.6 |
4.2 |
DT-90ov (days) |
769.5 |
922.7 |
425.4 |
408.7 |
23.9 |
40.8 |
DT-50(1): of fast degradation reactions
DT-50(2): of slow degradation reactions
DT-50ov: overall
DT-90ov: overall
Table: Distribution and Recovery of Radioactivity as Percent of Radioactivity: Weweantic River [triazinyl-6-14C]-test substance
Fraction |
Replicate |
Incubation time (days) |
||||||||
0 |
1 |
4 |
7 |
14 |
32 |
61 |
76 |
102 |
||
Surface water |
A |
94.9 |
77.8 |
45.8 |
25.0 |
12.6 |
8.0 |
7.2 |
6.4 |
7.7 |
B |
96.7 |
82.8 |
39.2 |
32.2 |
43.1 |
11.8 |
5.4 |
7.2 |
6.4 |
|
Mean |
95.8 |
80.3 |
42.5 |
28.6 |
27.9 |
9.9 |
6.3 |
6.8 |
7.1 |
|
Sediment Extraction 1a |
A |
ND |
9.7 |
22.1 |
22.5 |
14.6 |
15.4 |
4.7 |
5.3 |
4.2 |
B |
2.4 |
8.1 |
20.7 |
19.1 |
18.1 |
14.3 |
6.6 |
6.9 |
5.0 |
|
Mean |
1.2 |
8.9 |
21.4 |
20.8 |
16.3 |
14.8 |
5.6 |
6.1 |
4.6 |
|
Sediment Extraction 2a |
A |
NA |
4.3 |
7.7 |
11.3 |
7.0 |
8.6 |
2.7 |
3.2 |
2.5 |
B |
NA |
3.2 |
8.7 |
9.7 |
8.4 |
8.0 |
3.6 |
3.9 |
2.8 |
|
Mean |
NA |
3.8 |
8.2 |
10.5 |
7.7 |
8.3 |
3.1 |
3.5 |
2.6 |
|
Sediment Extraction 3a |
A |
NA |
2.4 |
4.5 |
5.1 |
4.8 |
5.6 |
1.7 |
2.3 |
1.7 |
B |
NA |
1.8 |
4.8 |
4.9 |
5.0 |
5.3 |
ND |
2.7 |
1.9 |
|
Mean |
NA |
2.1 |
4.7 |
5.0 |
4.9 |
5.5 |
0.9 |
2.5 |
1.8 |
|
Total Extractables (from sediment) |
Mean |
1.2 |
14.7 |
34.3 |
36.4 |
28.9 |
28.6 |
9.6 |
12.2 |
9.0 |
Sediment Extraction THF |
A |
NA |
0.6 |
2.8 |
3.2 |
2.2 |
5.8 |
1.4 |
1.4 |
2.3 |
B |
NA |
ND |
2.5 |
4.3 |
2.1 |
3.7 |
1.7 |
1.6 |
2.5 |
|
Mean |
NA |
0.3 |
2.7 |
3.8 |
2.2 |
4.8 |
1.6 |
1.5 |
2.4 |
|
Sediment Extraction Toluene |
A |
NA |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
B |
NA |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
|
Mean |
NA |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
|
Non-Extractables |
A |
ND |
7.7 |
18.9 |
37.6 |
53.5 |
52.3 |
56.6 |
57.0 |
52.0 |
B |
1.5 |
5.9 |
28.2 |
36.5 |
23.4 |
48.9 |
60.6 |
52.2 |
53.3 |
|
Mean |
0.8 |
6.8 |
23.6 |
37.1 |
38.5 |
50.6 |
58.6 |
54.6 |
52.6 |
|
14CO2 (NaOH) |
A |
NA |
NA |
0.2 |
0.9 |
4.6 |
4.2 |
22.5 |
15.4 |
16.6 |
B |
NA |
NA |
0.5 |
1.1 |
0.5 |
4.8 |
14.9 |
16.6 |
20.6 |
|
Mean |
NA |
NA |
0.4 |
1.0 |
2.5 |
4.5 |
18.7 |
16.0 |
18.6 |
|
VOC (Ethylene Glycol) |
A |
NA |
NA |
0.1 |
ND |
ND |
ND |
ND |
ND |
ND |
B |
NA |
NA |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
|
Mean |
NA |
NA |
0.1 |
ND |
ND |
ND |
ND |
ND |
ND |
|
TOTAL |
A |
94.9 |
102.5 |
102.3 |
105.7 |
99.3 |
99.9 |
96.8 |
91.0 |
87.0 |
B |
100.6 |
101.8 |
104.7 |
108.0 |
100.6 |
96.8 |
92.8 |
91.1 |
92.5 |
|
Mean |
97.7 |
102.2 |
103.5 |
106.8 |
100.0 |
98.3 |
94.8 |
91.0 |
89.8 |
|
Mean ± SD |
|
98.2 ± 5.7 |
||||||||
a Extracts 1, 2 and 3 extracted with 80:20 acetonitrile:purified reagent water (v:v).
Table: Distribution and Recovery of Radioactivity as Percent of Radioactivity: Weweantic River [Pyridinyl-6-14C]-Test substance)
Fraction |
Replicate |
Incubation time (days) |
||||||||
0 |
1 |
4 |
7 |
14 |
32 |
61 |
76 |
102 |
||
Surface water |
A |
101.1 |
78.5 |
58.3 |
34.5 |
9.8 |
4.0 |
2.5 |
2.5 |
ND |
B |
97.2 |
80.6 |
50.2 |
36.7 |
6.6 |
3.5 |
5.2 |
1.0 |
1.0 |
|
Mean |
99.1 |
79.5 |
54.2 |
35.6 |
8.2 |
3.7 |
3.9 |
1.8 |
0.5 |
|
Sediment Extraction 1a |
A |
ND |
8.4 |
16.0 |
17.8 |
11.0 |
8.0 |
6.4 |
2.9 |
2.5 |
B |
2.5 |
8.4 |
16.3 |
16.1 |
8.2 |
5.8 |
11.4 |
2.5 |
2.6 |
|
Mean |
1.2 |
8.4 |
16.1 |
16.9 |
9.6 |
6.9 |
8.9 |
2.7 |
2.6 |
|
Sediment Extraction 2a |
A |
NA |
3.7 |
6.5 |
10.1 |
6.8 |
5.1 |
3.3 |
1.8 |
1.6 |
B |
NA |
4.0 |
7.9 |
9.7 |
5.1 |
4.1 |
5.9 |
1.8 |
1.6 |
|
Mean |
NA |
3.8 |
7.2 |
9.9 |
6.0 |
4.6 |
4.6 |
1.8 |
1.6 |
|
Sediment Extraction 3a |
A |
NA |
1.9 |
3.6 |
4.6 |
4.5 |
3.6 |
2.3 |
1.4 |
1.1 |
B |
NA |
2.1 |
4.3 |
4.7 |
3.6 |
3.0 |
4.0 |
1.5 |
1.3 |
|
Mean |
NA |
2.0 |
4.0 |
4.6 |
4.0 |
3.3 |
3.1 |
1.4 |
1.2 |
|
Total Extractables (from sediment) |
Mean |
1.2 |
14.3 |
27.3 |
31.4 |
19.6 |
14.8 |
16.6 |
5.9 |
5.4 |
Sediment Extraction THF |
A |
NA |
0.6 |
2.0 |
2.7 |
2.1 |
2.7 |
1.6 |
ND |
1.7 |
B |
NA |
0.5 |
2.3 |
2.8 |
1.9 |
2.2 |
2.3 |
ND |
1.8 |
|
Mean |
NA |
0.6 |
2.1 |
2.8 |
2.0 |
2.4 |
2.0 |
ND |
1.7 |
|
Sediment Extraction Toluene |
A |
NA |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
B |
NA |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
|
Mean |
NA |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
|
Non-Extractables |
A |
ND |
6.2 |
21.1 |
31.7 |
47.4 |
47.4 |
45.1 |
34.6 |
30.1 |
B |
3.0 |
7.2 |
24.0 |
29.5 |
44.8 |
49.9 |
44.5 |
35.7 |
30.9 |
|
Mean |
1.5 |
6.7 |
22.5 |
30.6 |
46.1 |
48.6 |
44.8 |
35.2 |
30.5 |
|
14CO2 (NaOH) |
A |
NA |
NA |
1.1 |
2.5 |
20.9 |
29.7 |
28.2 |
46.4 |
47.7 |
B |
NA |
NA |
1.4 |
2.4 |
29.2 |
38.1 |
10.9 |
48.1 |
54.1 |
|
Mean |
NA |
NA |
1.3 |
2.5 |
25.1 |
33.9 |
19.5 |
47.3 |
50.9 |
|
VOC (Ethylene Glycol) |
A |
NA |
NA |
ND |
ND |
ND |
ND |
ND |
ND |
0.8 |
B |
NA |
NA |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
|
Mean |
NA |
NA |
ND |
ND |
ND |
ND |
ND |
ND |
0.4 |
|
TOTAL |
A |
101.1 |
99.4 |
108.4 |
103.8 |
102.5 |
100.4 |
89.5 |
89.5 |
85.4 |
B |
102.6 |
102.8 |
106.5 |
102.0 |
99.5 |
106.6 |
84.0 |
90.7 |
93.4 |
|
Mean |
101.9 |
101.1 |
107.5 |
102.9 |
101.0 |
103.5 |
86.8 |
90.1 |
89.4 |
|
Mean ± SD |
|
98.2 ± 7.4 |
||||||||
Table: Summary of Characterisation / Identification of Radioactive Residues in the Aerobic Weweantic River Water-Sediment System Treated with [triazinyl-6-14C]-Test substance as Percent of Applied Radioactivity (Total system)
[triazinyl-6-14C]- test substance |
Rep |
Sampling times (days) |
||||||||
0 |
1 |
4 |
7 |
14 |
32 |
61 |
76 |
102 |
||
Parent |
A |
94.9 |
92.4 |
77.0 |
58.7 |
21.3 |
27.3 |
6.7 |
7.2 |
6.0 |
B |
96.7 |
94.7 |
65.3 |
43.8 |
64.8 |
23.8 |
4.3 |
9.1 |
7.6 |
|
Mean |
95.8 |
93.5 |
71.1 |
51.3 |
43.1 |
25.5 |
3.1 |
8.2 |
6.8 |
|
M1 |
A |
ND |
ND |
1.2 |
ND |
ND |
1.8 |
4.8 |
2.4 |
0.7 |
B |
ND |
ND |
ND |
10.9 |
ND |
2.7 |
4.6 |
1.8 |
1.1 |
|
Mean |
ND |
ND |
0.6 |
5.4 |
ND |
2.2 |
4.7 |
2.1 |
0.9 |
|
M6 |
A |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
B |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
|
Mean |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
|
M5 (Polar) |
A |
ND |
1.9 |
1.2 |
5.3 |
5.1 |
0.5 |
8.5 |
1.2 |
1.4 |
B |
ND |
1.2 |
7.1 |
8.3 |
9.8 |
1.1 |
6.8 |
1.5 |
1.0 |
|
Mean |
ND |
1.6 |
4.1 |
6.8 |
7.4 |
0.8 |
7.7 |
1.4 |
1.2 |
|
Othersa |
A |
ND |
ND |
0.9 |
ND |
12.6 |
8.0 |
ND |
6.4 |
8.1 |
B |
2.4 |
ND |
1.0 |
3.0 |
ND |
11.8 |
ND |
7.2 |
6.4 |
|
Mean |
1.2 |
ND |
1.0 |
1.5 |
6.3 |
9.9 |
ND |
6.8 |
7.2 |
|
a) Individual components were< 5% AR.
ND = Not Detected
Table: Summary of Characterisation / Identification of Radioactive Residues in the Aerobic Weweantic River Water-Sediment System Treated with [triazinyl-6-14C]-Test
substance as Percent of Applied Radioactivity (Water phase)
[triazinyl-6-14C]- test substance |
Rep |
Sampling times (days) |
||||||||
0 |
1 |
4 |
7 |
14 |
32 |
61 |
76 |
102 |
||
Parent |
A |
94.9 |
77.8 |
45.8 |
25.0 |
ND |
ND |
ND |
ND |
ND |
B |
96.7 |
82.8 |
39.2 |
15.0 |
36.2 |
ND |
ND |
ND |
ND |
|
Mean |
95.8 |
80.3 |
42.5 |
20.0 |
18.1 |
ND |
ND |
ND |
ND |
|
M1 |
A |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
B |
ND |
ND |
ND |
10.9 |
ND |
ND |
ND |
ND |
ND |
|
Mean |
ND |
ND |
ND |
5.4 |
ND |
ND |
ND |
ND |
ND |
|
M6 |
A |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
B |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
|
Mean |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
|
M5 (Polar) |
A |
ND |
ND |
ND |
ND |
ND |
ND |
7.2 |
ND |
ND |
B |
ND |
ND |
ND |
3.4 |
6.9 |
ND |
5.4 |
ND |
ND |
|
Mean |
ND |
ND |
ND |
1.7 |
3.5 |
ND |
6.3 |
ND |
ND |
|
Othersa |
A |
ND |
ND |
ND |
ND |
12.6 |
8.0 |
ND |
6.4 |
7.7 |
B |
ND |
ND |
ND |
3.0 |
ND |
11.8 |
ND |
7.2 |
6.4 |
|
Mean |
ND |
ND |
ND |
1.5 |
6.3 |
9.9 |
ND |
6.8 |
7.1 |
|
a) Individual components were< 5% AR.
ND = Not Detected
Table: Summary of Characterisation / Identification of Radioactive Residues in the Aerobic Weweantic River Water-Sediment System Treated with [triazinyl-6-14C]-test substance as Percent of Applied Radioactivity (Sediment phase)
[triazinyl-6-14C]- test substance |
Rep |
Sampling times (days) |
||||||||
0 |
1 |
4 |
7 |
14 |
32 |
61 |
76 |
102 |
||
Parent |
A |
ND |
14.5 |
31.1 |
33.7 |
21.3 |
27.3 |
6.7 |
7.2 |
6.0 |
B |
ND |
11.8 |
26.1 |
28.9 |
28.6 |
23.8 |
4.3 |
9.1 |
7.6 |
|
Mean |
ND |
13.2 |
28.6 |
31.3 |
25.0 |
25.5 |
3.1 |
8.2 |
6.8 |
|
M1 |
A |
ND |
ND |
1.2 |
ND |
ND |
1.8 |
4.8 |
2.4 |
0.7 |
B |
ND |
ND |
ND |
ND |
ND |
2.7 |
4.6 |
1.8 |
1.1 |
|
Mean |
ND |
ND |
0.6 |
ND |
ND |
2.2 |
4.7 |
2.1 |
0.9 |
|
M6 |
A |
ND |
ND |
ND |
ND |
ND |
ND |
1.0 |
ND |
ND |
B |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
1.0 |
ND |
|
Mean |
ND |
ND |
ND |
ND |
ND |
ND |
0.5 |
0.5 |
ND |
|
M5 (Polar) |
A |
ND |
1.9 |
1.2 |
5.3 |
5.1 |
0.5 |
1.3 |
1.2 |
1.4 |
B |
ND |
1.2 |
7.1 |
4.9 |
2.8 |
1.1 |
1.3 |
1.5 |
1.0 |
|
Mean |
ND |
1.6 |
4.1 |
5.1 |
4.0 |
0.8 |
1.3 |
1.4 |
1.2 |
|
Others |
A |
ND |
ND |
0.9 |
ND |
ND |
ND |
ND |
ND |
0.3 |
B |
2.4 |
ND |
1.0 |
ND |
ND |
ND |
ND |
ND |
ND |
|
Mean |
1.2 |
ND |
1.0 |
ND |
ND |
ND |
ND |
ND |
0.2 |
|
ND = Not Detected
Table: Summary of Characterisation / Identification of Radioactive Residues in the Aerobic Weweantic River Water-Sediment System Treated with [pyridinyl-2-14C]-Test substance (Total system)
[pyridinyl-2-14C]- test substance |
Rep |
Sampling times (days) |
||||||||
0 |
1 |
4 |
7 |
14 |
32 |
61 |
76 |
102 |
||
Parent |
A |
101.1 |
92.6 |
83.0 |
54.5 |
17.9 |
13.6 |
8.1 |
4.2 |
4.1 |
B |
97.2 |
95.1 |
77.8 |
63.0 |
12.7 |
10.1 |
20.9 |
4.9 |
4.4 |
|
Mean |
99.1 |
93.8 |
80.4 |
58.8 |
15.3 |
11.8 |
14.5 |
4.6 |
3.7 |
|
M1 |
A |
ND |
ND |
1.3 |
12.4 |
4.4 |
3.1 |
3.9 |
1.9 |
1.1 |
B |
ND |
ND |
1.0 |
4.2 |
4.2 |
2.8 |
ND |
0.9 |
1.1 |
|
Mean |
ND |
ND |
1.1 |
8.3 |
4.3 |
3.0 |
2.0 |
1.4 |
1.1 |
|
M6 |
A |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
B |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
|
Mean |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
|
M5 (Polar) |
A |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
B |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
|
Mean |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
|
Othersa |
A |
ND |
ND |
ND |
ND |
9.8 |
4.0 |
2.5 |
2.5 |
ND |
B |
2.5 |
ND |
ND |
ND |
6.6 |
3.5 |
5.5 |
1.0 |
1.0 |
|
Mean |
1.2 |
ND |
ND |
ND |
8.2 |
3.7 |
4.0 |
1.8 |
0.5 |
|
a) Individual components were< 5% AR.
ND = Not Detected
Table: Summary of Characterisation / Identification of Radioactive Residues in the Aerobic Weweantic River Water-Sediment System Treated with [pyridinyl-2-14C]-Test substance (Water phase)
[pyridinyl-2-14C]- test substance |
Rep |
Sampling times (days) |
||||||||
0 |
1 |
4 |
7 |
14 |
32 |
61 |
76 |
102 |
||
Parent |
A |
101.1 |
78.5 |
58.3 |
25.4 |
ND |
ND |
ND |
ND |
ND |
B |
97.2 |
80.6 |
50.2 |
36.7 |
ND |
ND |
ND |
ND |
ND |
|
Mean |
99.1 |
79.5 |
54.2 |
31.1 |
ND |
ND |
ND |
ND |
ND |
|
M1 |
A |
ND |
ND |
ND |
9.1 |
ND |
ND |
ND |
ND |
ND |
B |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
|
Mean |
ND |
ND |
ND |
4.5 |
ND |
ND |
ND |
ND |
ND |
|
M6 |
A |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
B |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
|
Mean |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
|
M5 (Polar) |
A |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
B |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
|
Mean |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
|
Othersa |
A |
ND |
ND |
ND |
ND |
9.8 |
4.0 |
2.5 |
2.5 |
ND |
B |
ND |
ND |
ND |
ND |
6.6 |
3.5 |
5.2 |
1.0 |
1.0 |
|
Mean |
ND |
ND |
ND |
ND |
8.2 |
3.7 |
3.9 |
1.8 |
0.5 |
|
a) Individual components were< 5% AR.
ND = Not Detected
Table: Summary of Characterisation / Identification of Radioactive Residues in the Aerobic Weweantic River Water-Sediment System Treated with [pyridinyl-2-14C]-Test substance (Sediment phase)
[pyridinyl-2-14C]- test subtance |
Rep |
Sampling times (days) |
||||||||
0 |
1 |
4 |
7 |
14 |
32 |
61 |
76 |
102 |
||
Parent |
A |
ND |
14.1 |
24.7 |
29.1 |
17.9 |
13.6 |
8.1 |
4.2 |
4.1 |
B |
ND |
14.5 |
27.5 |
26.3 |
12.7 |
10.1 |
20.9 |
4.9 |
4.4 |
|
Mean |
ND |
14.3 |
26.1 |
27.7 |
15.3 |
11.8 |
14.5 |
4.6 |
3.7 |
|
M1 |
A |
ND |
ND |
1.3 |
3.3 |
4.4 |
3.1 |
3.9 |
1.9 |
1.1 |
B |
ND |
ND |
1.0 |
4.2 |
4.2 |
2.8 |
ND |
0.9 |
1.1 |
|
Mean |
ND |
ND |
1.1 |
3.7 |
4.3 |
3.0 |
2.0 |
1.4 |
1.1 |
|
M6 |
A |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
1.1 |
B |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
|
Mean |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
0.5 |
|
M5 (Polar) |
A |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
B |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
|
Mean |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
|
Others |
A |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
ND |
B |
2.5 |
ND |
ND |
ND |
ND |
ND |
0.2 |
ND |
ND |
|
Mean |
1.2 |
ND |
ND |
ND |
ND |
ND |
0.1 |
ND |
ND |
|
ND = Not Detected
Table: Summary of Dissipation and Degt50 values
Water-sediment System |
Radiolabel |
Phase |
SFO |
||||
DT50(days) |
DT90(days) |
Chi2 |
R2 |
Prob>t |
|||
Weweantic River |
[Triazinyl-14C] |
Water |
3.6 |
12 |
9.74 |
0.9311 |
4.89E-005 |
Total |
13 |
42 |
11.6 |
0.9219 |
1.35E-005 |
||
Weweantic River |
[Pyridinyl-14C] |
Water |
4.0 |
13 |
7.26 |
0.9755 |
3.30E-006 |
Total |
7.6 |
25 |
14.9 |
0.9593 |
3.98E-007 |
||
Weweantic River |
Combined |
Water |
3.8 |
13 |
2.14 |
0.9539 |
5.95E-011 |
Total |
9.5 |
32 |
10.5 |
0.9344 |
8.94E-011 |
||
Note: SFO: simple first order kinetics (non-linear method) calculated using CAKE software (version 3.1). DegT50: Calculated degradation half-life of parent. K: rate constant. χ2: chi-square statistical value. R2: linear regression coefficient. Prob> t: statistical probability value related to a statistical t-test calculation.
Description of key information
After re-evaluation of data from two different studies, the DT50 (water) is 9.5 d and DT50 (sediment) is 312 d.
The OECD TG 308 study by Turk (2016) was not taken into consideration to maintain a conservative risk assessment approach.
All available data was assessed and the studies representing the worst-case effects were included as weight-of-evidence studies. The other studies are included as supporting information. The weight-of-evidence studies are considered to be worst-case and were selected for the CSA.
Key value for chemical safety assessment
- Half-life in freshwater:
- 9.5 d
- at the temperature of:
- 20 °C
- Half-life in freshwater sediment:
- 312 d
- at the temperature of:
- 20 °C
Additional information
Table: Combined water-phase results of the simulation tests (BBA part IV, 5-1 / GLP) in water and sediment and the remodelled data for the purpose of risk assessment
Compartment |
Radiolabel |
Endpoint |
Original value (days) |
Recalculated (FOMC), normalised DT50 value at P-I level (a, b) (days) |
DT50 (days) geometric mean of both labels |
Reference |
Natural water: freshwater (Pond) |
Pyridinyl-labelled |
DT50 |
4.75 |
8.5 |
7.9 |
Reischmann, 1995 |
Triazinyl-labelled |
DT50 |
4.6 | 7.4 |
Schulze-Aurich, 1996 |
||
Natural water: freshwater (Rhine)
|
Pyridinyl-labelled |
DT50 |
6.29 |
9.8 |
11.3 |
Reischmann, 1995 |
Triazinyl-labelled |
DT50 |
4.2 |
13.1 |
Schulze-Aurich, 1996 |
||
Geometric mean (n=2) |
9.5 |
|
||||
a) Kinetic modelling at level P-I was carried out using KinGUI (2006). The acceptability of the kinetic fits was judged both visually and statistically, using the χ2 error% and the t-test functions, as recommended by FOCUS Kinetics (2006).
b) DT50 calculated as FOMC DT90/3.32
Table: Combined sediment-phase results of the simulation tests (BBA part IV, 5-1 / GLP) in water and sediment and the remodelled data for the purpose of risk assessment
Compartment |
Radiolabel |
Endpoint |
Original value (days) |
Recalculated (SFO), normalised DT50 value at P-I level (a) (days) |
DT50 (days) geometric mean of both labels |
Reference |
Natural sediment: freshwater (Pond) |
Pyridinyl-labelled |
DT50 |
NR |
425 |
346 |
Reischmann, 1995 |
Triazinyl-labelled |
DT50 |
NR |
282 |
Schulze-Aurich, 1996 |
||
Natural sediment: freshwater (Rhine)
|
Pyridinyl-labelled |
DT50 |
NR |
265 |
282 |
Reischmann, 1995 |
Triazinyl-labelled |
DT50 |
NR |
299 |
Schulze-Aurich, 1996 |
||
Geometric mean (n=2) |
312 |
|
||||
NR – Not reported
a) Kinetic modelling at level P-I was carried out using KinGUI (2006). The acceptability of the kinetic fits was judged both visually and statistically, using the χ2 error% and the t-test functions, as recommended by FOCUS Kinetics (2006).
Table: Combined whole-system results of the simulation tests (BBA part IV, 5-1 / GLP) in water and sediment and the remodelled data for the purpose of risk assessment
Compartment |
Radiolabel |
Endpoint |
Original value (slow-phase; days) |
Recalculated (DFOP), normalised DT50 value at P-I level (a, b) (days) |
DT50 (days) geometric mean of both labels |
Reference |
sediment: freshwater (pond total water-sediment system) |
Pyridinyl-labelled |
DT50 |
100.29 |
495 |
395 |
Reischmann, 1995 |
Triazinyl-labelled |
DT50 |
338.1 |
315 |
Schulze-Aurich, 1996 |
||
Natural water / sediment: freshwater (Rhine total water-sediment system) |
Pyridinyl-labelled |
DT50 |
143.27 |
289 |
325 |
Reischmann, 1995 |
Triazinyl-labelled |
DT50 |
378.8 |
365 |
Schulze-Aurich, 1996 |
||
Geometric mean (n=2) |
358 |
|
||||
a) Kinetic modelling at level P-I was carried out using KinGUI (2006). The acceptability of the kinetic fits was judged both visually and statistically, using the χ2 error% and the t-test functions, as recommended by FOCUS Kinetics (2006).
b) DT50 calculated from slow phase of the DFOP model
Information on Registered Substances comes from registration dossiers which have been assigned a registration number. The assignment of a registration number does however not guarantee that the information in the dossier is correct or that the dossier is compliant with Regulation (EC) No 1907/2006 (the REACH Regulation). This information has not been reviewed or verified by the Agency or any other authority. The content is subject to change without prior notice.
Reproduction or further distribution of this information may be subject to copyright protection. Use of the information without obtaining the permission from the owner(s) of the respective information might violate the rights of the owner.
