Octanethioic acid, S-[3-(triethoxysilyl)propyl] ester, reaction products with 2-methyl-1,3-propanediol and 3-(triethoxysilyl)-1-propanethiol

Toxicity to soil macroorganisms except arthropods

Some information in this page has been claimed confidential.

Administrative data

Endpoint:

toxicity to soil macroorganisms except arthropods: short-term

Data waiving:

study scientifically not necessary / other information available

Justification for data waiving:

the study does not need to be conducted because direct and indirect exposure of the soil compartment is unlikely

Cross-reference

Reason / purpose for cross-reference:

data waiving: supporting information

Reference

Endpoint:

hydrolysis

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2008-03-19 - 2008-05-13

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 111 (Hydrolysis as a Function of pH)

Qualifier:

according to guideline

Guideline:

EU Method C.7 (Degradation: Abiotic Degradation: Hydrolysis as a Function of pH)

Principles of method if other than guideline:

A preliminary test was performed at 50ºC ± 0.1ºC at each of pH 4.0, pH 7.0, and pH 9.1.The test item was dissolved in an aqueous solution at a specific pH-value and was incubated at a specific temperature to observe its hydrolysis behavior. The solutions were continuously stirred using a magnetic stirrer. The concentration of 2-methyl-1,3-propane diol, a hydrolysis product, was determined as a function of time at each pH.

GLP compliance:

no

Radiolabelling:

no

Analytical monitoring:

yes

Details on sampling:

- Sampling method: At each sampling point, a 3 ml aliquot of the test solutions at each pH value was transferred to a vial and subjected to GC analysis
- Sampling intervals/times for pH measurements: pH 4.0, pH 7.0, pH 9.1

Transformation products:

yes

No.:

#1

Key result

pH:

7

Temp.:

50 °C

Hydrolysis rate constant:

0 s-1

DT50:

8.2 h

pH:

9

Temp.:

50 °C

Hydrolysis rate constant:

0 s-1

DT50:

5.5 h

pH:

4

Temp.:

50 °C

Hydrolysis rate constant:

0 s-1

DT50:

4.8 h

Details on results:

The results of the individual measurements are summarized in the attached table.
The results of pH 4.0, pH 7.0, and pH 9.1 showed significant degradation of the test item at 50ºC. The degradation of the test item was higher than 50% after 14 hours at pH 7. Hydrolysis was faster at pH of 4 and 9.
According to the EEC Directive 92/69, Section C.7, it can be concluded that the estimated half-life time is shorter than one day under representative environmental conditions (25ºC). Therefore the registered substance was considered to be hydrolytically unstable.

Validity criteria fulfilled:

not specified

Conclusions:

NXT Z45 was found to be hydrolytically unstable.