Copper glycinate sulfate

Biodegradation in water: screening tests

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

supporting study

Reliability:

3 (not reliable)

Rationale for reliability incl. deficiencies:

other: test meets generally accepted principles but with insufficient documentation, test performed prior to implementation of standard methods

Qualifier:

no guideline followed

Principles of method if other than guideline:

- Principle of test: Bacillus proteus Type X-2 was grown for 18 hours on beef extract agar slants at 37° and pH 7.4. Subsequently, 1 cc. of the suspension of bacteria was used in each Warburg vessel and the volume made up to 2 cc. with buffer and a solution of the amino acid to be tested.
- Short description of test conditions: The bacteria were then scraped off the slants, suspended in saline, and centrifuged. This washing was
repeated three times and then the bacteria were suspended in 0.05 M phosphate buffer of pH 7.8 so that there were approximately 7 billion per cc. The optimum pH for the oxidation of the amino acids is between 7.6 and 8.3.
- Parameters analysed / observed: The rate and amount of the oxygen uptake was then measured.

GLP compliance:

no

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge (adaptation not specified)

Duration of test (contact time):

6 h

Initial conc.:

0.25 other: mg

Based on:

test mat.

Parameter followed for biodegradation estimation:

O2 consumption

Details on study design:

TEST SYSTEM
- Culturing apparatus: Warburg vessels

Reference substance:

not specified

Key result

Parameter:

% degradation (O2 consumption)

Value:

104

Sampling time:

110 min

Remarks on result:

other: Observed O2 uptake

Remarks:

sampling time gives the oxidation rate based on the time necessary to reach one-half the final uptake

Validity criteria fulfilled:

not applicable

Interpretation of results:

readily biodegradable

Conclusions:

In the present study of Bernheim et al. 'resting' Bacillus proteus were incubated with different amino acids, i.a. with 0.25 mg/cm³ glycine. The determined oxidation rate was 110 min and the oxygen uptake was 104 cm³. Furthermore, it was reported that glycine was completely metabolised in contrast to the other amino acids investigated. Thus, glycine is considered to be readily biodegradable under the conditions of the test.

Executive summary:

The biodegradation of glycine was determined in Bacillus proteus. The method of determination is considered sufficient, the study was conducted prior to implementation of standard guidelines. Bacillus proteus Type X-2 was grown for 18 hours on beef extract agar slants at 37° and pH 7.4. Subsequently,  a suspension of bacteria  was  used  in  each  Warburg  vessel  and  the  volume  made  up  to  2  cc.  with  buffer  and  a  solution  of  the  amino  acid  to  be  tested. The oxidation rate was measured after 6h. The authors were able to show that glycine in contrast to all other proteinogenic amino acids was fully metabolised by resting Bacillus proteus. Thus, glycine is considered readily biodegradable under the conditions of the test.

Reference 2

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Qualifier:

no guideline followed

Principles of method if other than guideline:

- Principle of test:
Determination of oxygen uptake/oxidation of the compound using the Warburg respirometer
- Short description of test conditions: Exposure of individual chemical compounds at a concentration of 500 mg/L to activated sludge solids at 2,500 mg/L in the Warburg respirometer with oxygen uptake as the measure of oxidation of the compound. The theoretical oxygen demand (TOD) is defined as the concentration of oxygen in mg/L required to oxidize 500 mg/L of substrate completely, i.e., to CO2, water, nitrate, sulfate, and chlorate.

GLP compliance:

no

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge (adaptation not specified)

Duration of test (contact time):

24 h

Initial conc.:

500 mg/L

Based on:

test mat.

Parameter followed for biodegradation estimation:

O2 consumption

Remarks:

percent from TOD

Reference substance:

other: no

Key result

Parameter:

% degradation (O2 consumption)

Remarks:

percent of TOD

Value:

16.9

Sampling time:

24 h

Validity criteria fulfilled:

not applicable

Interpretation of results:

readily biodegradable

Conclusions:

In the present study of Malaney and Gerhold the biological oxygen demand, i.e. the concentration of oxygen in mg/L required to oxidize 500 mg/L of substrate completely, of activated sludge incubated with glycine was determined. The result reveals that 16.9 % of the compound were degraded within 24 h, therefore glycine is less susceptible to oxidation than the other amino-acids investigated but considered readily biodegradable because it belongs to the same chemical family as the amino acids that are more susceptible to oxidation.

Executive summary:

In the study of Malaney (1969) the biological oxygen demand of activated sludge incubated with glycine was determined. Again, this study was conducted prior to implementation of standard guidelines and GLP. The study was reported in sufficient detail and provides evidence that glycine is readily biodegradable. The result reveals that 16.9 % of the compound were degraded within 24 h, therefore glycine is less susceptible to oxidation than the other amino-acids investigated but considered readily biodegradable because it belongs to the same chemical family as the amino acids that are more susceptible to oxidation.

Reference 3

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Qualifier:

no guideline followed

Principles of method if other than guideline:

- Principle of test: The oxidation studies were carried out using a closed system aeration chamber actuated by a mercury pump and containing a known volume of air. The initial oxygen content may be determined as well as subsequent changes at appropriate intervals by withdrawing small samples of pair for analysis. Aeration with each substance was continued for 22 to 24 hours, and samples taken at 1, 3, 5 and 22- to 24-hour periods. A constant temperature of 20° C. was maintained throughout the oxidation period. A basic mineral buffer solution was used. The activated sludge was maintained at 2,000 ppm. The test materials were the only source of energy, the controls contained carbon without the test material. The pH was recorded
- Parameters analysed / observed: Biochemical oxygen demand every two days for 10 days.
Study was conducted prior to implementation of GLP or OECD guidelines.

GLP compliance:

no

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge (adaptation not specified)

Duration of test (contact time):

10 d

Initial conc.:

720 mg/L

Based on:

test mat.

Parameter followed for biodegradation estimation:

other: BOD

Details on study design:

TEST CONDITIONS
- Composition of medium: A The following ions were contained in this solution: ammonium, sodium, potassium, calcium, magnesium, phosphate, sulfate and chloride.
- pH adjusted: no
- Suspended solids concentration: 2,000 ppm

TEST SYSTEM
- Culturing apparatus: closed system aeration chamber actuated by a mercury pump

SAMPLING
- Sampling frequency: every two days

CONTROL AND BLANK SYSTEM
- Inoculum blank: yes, same conditions as with the test substances

Reference substance:

not specified

Key result

Parameter:

other: BOD

Value:

86.9

Sampling time:

24 h

Remarks on result:

other: Percentage of BOD observed after mixing removed in 22 to 24 h

Validity criteria fulfilled:

not applicable

Interpretation of results:

readily biodegradable

Conclusions:

In the present study of Placak and Ruchcroft data pertains to the removal from solution, oxidation, and conversion to protoplasm by activated sludge, of 36 pure organic substances are reported. Activated sludge was incubated with 720 mg/L glycine and the oxygen removal based on biochemical oxygen demand was determined over 10 days. The results showed that 86.9% of the BOD was removed after 22 to 24h. Thus, glycine is considered to be readily biodegradable under the conditions of the test.

Executive summary:

The biodegradation of glycine was determined in a study from Placak (1947). Activated sludge was incubated with 36 pure organic compounds including 720 mg/L glycine. The BOD was measured over 10 days. The results showed that 86.9% of the BOD was removed after 22 to 24h. Thus, glycine is considered to be readily biodegradable under the conditions of the test.

Reference 4

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

(Q)SAR

Adequacy of study:

supporting study

Study period:

2019-12-04

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

results derived from a valid (Q)SAR model and falling into its applicability domain, with adequate and reliable documentation / justification

Justification for type of information:

1. SOFTWARE
EPISUITE v4.11
2. MODEL (incl. version number)
BIOWIN v4.10
3. SMILES: for details on the SMILES notations that have been used for QSAR, please see the attached justification.
4. SCIENTIFIC VALIDITY OF THE (Q)SAR MODEL
For detailed information about the used model please refer to the attached justification.
5. APPLICABILITY DOMAIN
For detailed information about the used model please refer to the attached justification.
6. ADEQUACY OF THE RESULT
For detailed information about the used model please refer to the attached justification.

Qualifier:

no guideline followed

Principles of method if other than guideline:

For detailed description, please see attached justification.

GLP compliance:

no

Oxygen conditions:

aerobic/anaerobic

Inoculum or test system:

not specified

Details on inoculum:

QSAR; not applicable

Details on study design:

QSAR calculation

Preliminary study:

not applicable

Details on results:

Ready Biodegradability Prediction according to BIOWIN v4.10: YES

Validity criteria fulfilled:

not applicable

Remarks:

supporting QSAR calculation of glycine

Interpretation of results:

readily biodegradable

Conclusions:

According to QSAR calculation using BIOWIN v4.10, the test substance is readily biodegradable.

Executive summary:

In this study, the test substance glycine was estimated to be readily biodegradable using BIOWIN v4.10.

Reference 5

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

key study

Justification for type of information:

REPORTING FORMAT FOR THE ANALOGUE APPROACH
1. HYPOTHESIS FOR THE ANALOGUE APPROACH
This read-across hypothesis is based on transformation of the target and source substances to common compounds (scenario 1 of the RAAF). The target substance copper monoglycinate sulfate and the source substances copper sulfate and copper bisglycinate consist of the Cu2+ cation and the respective anion. The amino acid glycine is constituent of both the target substance copper monoglycinate sulfate and the source substance copper bisglycinate.
It is generally accepted that the Cu2+ cation (as measure for dissolved copper species) is the determining factor for toxicity and ecotoxicity, but not sulfate or glycine.
2. SOURCE AND TARGET CHEMICAL(S) (INCLUDING INFORMATION ON PURITY AND IMPURITIES)
The target substance copper monoglycinate sulfate is a chelate-complex which consists of the divalent copper ion as centre-ion and glycine as ligand. The remaining sulfate group stabilizes the center ion within the complex.
Copper monoglycinate sulfate and the source substance copper sulfate are ionic and consist of the Cu2+ cation and the respective anions. It is generally accepted that the copper cation is the determining factor for toxicity and ecotoxicity. Therefore, this read-across approach is based on the assumption that the metal cation of both the target and the source substance, copper, is the relevant component for assessment of toxicity and ecotoxicity.
The anion of the target substance is the essential amino acid glycine and the sulfate anion. In the source substance, it is the sulfate anion. These anions are not considered as (eco)toxicologically relevant at the given concentrations.
Please refer to the justification for read-across analogue approach in Chapter 13.2 for more detailed information.
3. ANALOGUE APPROACH JUSTIFICATION
Please refer to the justification for read-across analogue approach in Chapter 13.2 for more detailed information.
4. DATA MATRIX
Please refer to the justification for read-across analogue approach in Chapter 13.2 for more detailed information.

Reason / purpose for cross-reference:

read-across source

Reason / purpose for cross-reference:

read-across source

Reason / purpose for cross-reference:

read-across source

Reason / purpose for cross-reference:

read-across source

Key result

Parameter:

% degradation (O2 consumption)

Remarks:

percent of TOD

Value:

16.9

Sampling time:

24 h

Remarks on result:

other: Results for glycine obtained from Malaney et al. (1969)

Key result

Parameter:

other: BOD

Value:

86.9

Sampling time:

24 h

Remarks on result:

other: Results for glycine obtained from Placak (1947)

Key result

Parameter:

% degradation (O2 consumption)

Value:

104

Sampling time:

110 min

Remarks on result:

other: Observed O2 uptake

Remarks:

sampling time gives the oxidation rate based on the time necessary to reach one-half the final uptake. Results for glycine obtained from Bernheim (1935).

Validity criteria fulfilled:

not applicable

Interpretation of results:

readily biodegradable

Conclusions:

Data on biodegradation of copper monoglycinate sulfate are not available. However, since the test item consists of glycine and the inorganic copper and sulfate ions, only data on the biodegradation of glycine is provided. Several published studies provide evidence that glycine is readily biodegradable. Moreover, glycine is present in virtually every living organism and it is an integral part of the interediary metabolism and can be used as carbon source for energy supply. Thus, microorganisms contained in the (activated) sludge are considered to metabolise amino acids very fast. Based on the available data glycine is considered to be readily biodegradable.

Executive summary:

Data on biodegradation of copper monoglycinate sulfate are not available. However, there are several studies providing evidence that glycine as one of the proteinogenic amino acids is readily biodegradable.

In the study of Bernheim (1935) the biodegradation of glycine was determined in Bacillus proteus. The method of determination is considered sufficient, the study was conducted prior to implementation of standard guidelines. Bacillus proteus Type X-2 was grown for 18 hours on beef extract agar slants at 37°C and pH 7.4. Subsequently, a suspension of bacteria was used in each Warburg vessel and the volume made up to 2 cc. with buffer and a solution of the amino acid to be tested. The oxidation rate was measured after 6h. The authors were able to show that glycine in contrast to all other proteinogenic amino acids was fully metabolised by resting Bacillus proteus. Thus, glycine is considered readily biodegradable under the conditions of the test.

In another study of Placak (1947) the biodegradation of glycine was determined via measurement of the BOD. Activated sludge was incubated with 36 pure organic compounds including 720 mg/L glycine. The BOD was measured over 10 days. The results showed that 86.9% of the BOD was removed after 22 to 24h. Thus, glycine is considered to be readily biodegradable under the conditions of the test.

Finally, Malaney (1969) compared the biodegradation of all proteinogenic amino acids. The biological oxygen demand of activated sludge incubated with glycine was determined. Again, this study was conducted prior to implementation of standard guidelines and GLP. The study was reported in sufficient detail and provides evidence that glycine is readily biodegradable. The result reveals that 16.9 % of the compound were degraded within 24 h, therefore glycine is less susceptible to oxidation than the other amino-acids investigated but considered readily biodegradable because it belongs to the same chemical family as the amino acids that are more susceptible to oxidation.

Based on the presented data glycine is considered to be readily biodegradable.

 

 

Description of key information

Data on biodegradation of zinc monoglycinate sulfate are not available. However, since the test item consists of glycine and the inorganic zinc and sulfate ion, only data on the biodegradation of glycine is provided. Several published studies provide evidence that glycine is readily biodegradable. Moreover, glycine is present in virtually every living organism and it is an integral part of the interediary metabolism and can be used as carbon source for energy supply. Thus, microorganisms contained in the (activated) sludge are considered to metabolise amino acids very fast. Based on the available data glycine is considered to be readily biodegradable.

Key value for chemical safety assessment

Biodegradation in water:

readily biodegradable

Type of water:

freshwater