7-(diethylamino)-4-methyl-2-benzopyrone

Hydrolysis

Link to relevant study record(s)

Reference

Endpoint:

hydrolysis

Type of information:

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

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

data from handbook or collection of data

Remarks:

experimental data of read across substances

Justification for type of information:

Data for the target chemical is summarized based on the structurally similar read across chemicals

Reason / purpose for cross-reference:

read-across source

Reason / purpose for cross-reference:

read-across source

Qualifier:

according to guideline

Guideline:

other: as mentioned below

Principles of method if other than guideline:

WoE report is based on two hydrolysis studies as-
2. and 3.

GLP compliance:

not specified

Radiolabelling:

not specified

Analytical monitoring:

not specified

Estimation method (if used):

2. no data available
3. Structure estimation method

Duration:

20 d

Remarks:

2. The study was performedat pH range7.4 to 7.8 & 20.1 to 20.5⁰C, respectively. Test chemical conc. measuredwere 0.0287, 0.0320, 0.0334, 0.0349, 0.0251, 0.0311, 0.0414, 0.0370, 0.0362 & 0.0363 mg/l at 0, 1, 3, 6, 8, 10, 13, 15, 17 & 20 days, respectively.

Positive controls:

not specified

Negative controls:

not specified

Transformation products:

not specified

Key result

Remarks on result:

other: 2. Although half-life value of chemical was not known, but based on the measured concentration of test chemical in water, chemical appears to be in equilibrium and does not appear to be breaking down in water.

pH:

7

DT50:

1.4 yr

Type:

second order

Remarks on result:

other: 3. Hydrolysis rate constant is 0.16 L/mol-sec.

pH:

8

DT50:

51 d

Type:

second order

Remarks on result:

other: 3. Hydrolysis rate constant is 0.16 L/mol-sec.

Details on results:

2. Based on the measured concentration of test chemical in water, chemical was reported to be hydrolytically stable at pH range 7.4 to 7.8 and a temperature of 20.1 to 20.5⁰C for 20 days. Test chemical appears to be in equilibrium and does not appear to be breaking down in water. The concentration of test chemical is not decreasing with time.

Validity criteria fulfilled:

not specified

Conclusions:

On the basis of the experimental studies of the test chemical and applying the weight of evidence approach, the hydrolysis half-life value of the test chemical can be expected to be ranges from > 20 days to 1.4 yr, at pH range 7-8 & temperature of 20.1-20.5⁰C, respectively. Thus, based on this half-life value, it can be concluded that the test chemical is not hydrolysable in water.

Executive summary:

Data available for the test chemical has been reviewed to determine the half-life of hydrolysis as a function of pH. The studies are as mentioned below:

The half-life of the test chemical was determined at different pH range. The study was performedat apH range7.4 to 7.8 and a temperature of 20.1 to 20.5⁰C, respectively.The test substance was dissolved in dechlorinated tap water. The concentration of the test substance was measured in the supernatant of the test solution centrifuged. The test substance was measured on day 0, 1, 3, 6, 8, 10, 13, 15, 17, and 20 over a 21-day period. The test concentration used was considered to be at saturation in water. Based on the measured concentration of test chemical in water, chemical was reported to be hydrolytically stable at pH range7.4 to 7.8 and a temperature of 20.1 to 20.5⁰C for 20 days. Test chemical appears to be in equilibrium and does not appear to be breaking down in water. The concentration of test chemical is not decreasing with time. Thus, the half-life value of test chemical was determined to be > 20 days and on the basis of this, test chemical is considered to be not hydrolysable.

In an another study, the half-life and base catalyzed second order hydrolysis rate constant was determined using a structure estimation method of the test chemical. The second order hydrolysis rate constant of test chemical was determined to be 0.16L/mol-sec with a corresponding half-lives of 1.4 yrs and 51 days at pH 7 and 8, respectively. Based on the half-life values, it is concluded that the test chemical is not hydrolysable.

On the basis of the experimental studies of the test chemical and applying the weight of evidence approach, the hydrolysis half-life value of the test chemical can be expected to be ranges from > 20 days to 1.4 yr, at pH range 7-8 & temperature of 20.1-20.5⁰C, respectively. Thus, based on this half-life value, it can be concluded that the test chemical is not hydrolysable in water.

Description of key information

On the basis of the experimental studies of the test chemical and applying the weight of evidence approach, the hydrolysis half-life value of the test chemical can be expected to be ranges from > 20 days to 1.4 yr, at pH range 7-8 & temperature of 20.1-20.5⁰C, respectively. Thus, based on this half-life value, it can be concluded that the test chemical is not hydrolysable in water.

Key value for chemical safety assessment

Half-life for hydrolysis:

20 d

at the temperature of:

20.5 °C

Additional information

Data available for the test chemical has been reviewed to determine the half-life of hydrolysis as a function of pH. The studies are as mentioned below:

 

The half-life of the test chemical was determined at different pH range. The study was performed at a pH range7.4 to 7.8 and a temperature of 20.1 to 20.5⁰C, respectively. The test substance was dissolved in dechlorinated tap water. The concentration of the test substance was measured in the supernatant of the test solution centrifuged. The test substance was measured on day 0, 1, 3, 6, 8, 10, 13, 15, 17, and 20 over a 21-day period. The test concentration used was considered to be at saturation in water. Based on the measured concentration of test chemical in water, chemical was reported to be hydrolytically stable at pH range7.4 to 7.8 and a temperature of 20.1 to 20.5⁰C for 20 days. Test chemical appears to be in equilibrium and does not appear to be breaking down in water. The concentration of test chemical is not decreasing with time. Thus, the half-life value of test chemical was determined to be > 20 days and on the basis of this, test chemical is considered to be not hydrolysable.

 

In an another study, the half-life and base catalyzed second order hydrolysis rate constant was determined using a structure estimation method of the test chemical. The second order hydrolysis rate constant of test chemical was determined to be 0.16L/mol-sec with a corresponding half-lives of 1.4 yrs and 51 days at pH 7 and 8, respectively. Based on the half-life values, it is concluded that the test chemical is not hydrolysable.

 

On the basis of the experimental studies of the test chemical and applying the weight of evidence approach, the hydrolysis half-life value of the test chemical can be expected to be ranges from > 20 days to 1.4 yr, at pH range 7-8 & temperature of 20.1-20.5⁰C, respectively. Thus, based on this half-life value, it can be concluded that the test chemical is not hydrolysable in water.