4-(2-chlorophenyl)-N-cyclohexyl-N-ethyl-5-oxo-4,5-dihydro-1H-tetrazole-1-carboxamide

Storage stability and reactivity towards container material

Link to relevant study record(s)

Reference

Endpoint:

storage stability and reactivity towards container material

Type of information:

experimental study

Adequacy of study:

key study

Study period:

Jun 03 1997 - Jul 19 1999

Reliability:

1 (reliable without restriction)

Qualifier:

according to guideline

Guideline:

EPA OPPTS 830.6320 (Corrosion Characteristics)

Qualifier:

according to guideline

Guideline:

EPA OPPTS 830.6313 (Storage Stability)

Qualifier:

according to guideline

Guideline:

other: OPPTS 830.6317

GLP compliance:

yes

Type of method:

accelerated testing

Results:

The corrosion compatibility test (2 weeks, 54°C) has been completed in compliance with the EPA-Guidelines. All of the test materials evaluated in this study are suitable and can be recommended for general use with the product.
The results from a 1 year storage at ambient conditions showed test substance to be stable regarding shelf life conditions. During the storage no changes of the test substance were established. No deterioration of the packaging material was observed.

Transformation products:

no

Storage stability / reactivity towards container material:

other: During the storage no changes of the test substance were established. No deterioration of the packaging material was observed.

Analytical results, corrosion compatibility test

	Content of test item [%]
	single values	mean value
Reference sample at initiation of storage	99.1 99.6	99.4 (water content: 0.37 %*)
after 2 weeks, 54°C
Reference sample	99.5 100.0	> 99.5
Aluminium	100.0 100.3	> 99.5
Copper	100.5 99.6	> 99.5
Brass	99.9 99.9	> 99.5
Plain Steel	100.6 100.4	> 99.5
Stainless Steel 1.4541	100.4 99.8	> 99.5 (water content: 0.29 %*)
Tinplate	100.7 99.6	> 99.5
HDPE	99.8 99.5	> 99.5
PET/AL/PA/PELaminate	99.8 100.6	> 99.5
Cardboard	100.0 99.7	> 99.5

* determination by Karl Fischer titration according CEP AC MT 30.1

Table above shows little higher values in content a. i. for the stored samples (single values between 99.5 % and 100.7 %) compared to the reference sample at initiation of the study (mean = 99.4 %). The measurements for determination of a. i. were performed under Reproducing conditions (at the initiation of the study and after 2 weeks at different times and at different instruments). Experience shows that RSD values under reproducing conditions are expected to be higher than under repeating conditions (= determinations within a short time intervall, at the same instrument, with the same personell; RSDreproducibility > RSD repeatability). Considering the RSD values under repeating conditions (time zero: 0.88 % ; accelerated test: 0.55 %, see table below) and due to the reproducing conditions the found values of content a.i. after two weeks are within the expected standard deviation. Following the ,,seeming increase" of a. i. content assessed to be no significant. It is a common practice in evaluation of content a.i. in technical samples to declarate the content as „> 99.5" in the case of scattering values around 100 % because of nearly the same purity of reference and sample to be determined.

In addition to the determinations of content a.i. water content was determined at two random selected samples.

Analytical results, storage stability test

	Content of test item [%]
	single values	mean value
Reference sample at initiation of storage	99.1 99.6	99.4 (water content: 0.37 %*)
after 2 weeks, 54°C	100.2 100.4	> 99.5 (water content = 0.28 %*)
12 weeks, ambient conditions	99.3 99.9	> 99.5
24 weeks, ambient conditions	99.5 100.0	> 99.5
1 year, ambient conditions	99.2 100.4 99.1 100.0	> 99.5
2 years, ambient conditions	99.9 100.9	> 99.5

* determination by Karl Fischer titration according CIPAC MT 30.1

Table "Analytical results, storage stability test" shows little higher values in content a. i. for the stored samples (single values between 99.1 % and 100.9 %, mean > 99.5 %) compared to the reference sample at initiation of the study (mean = 99.4 %). Due to the reproducing conditions (see comments above) the little changes in content a.i. after storage are assessed to be no significant. In addition to the determinations of content a.i. water content was determined at initiation and after 2 weeks storage at 54 °C.

Description of key information

No changes of the test substance nor deterioration of the packaging material were observed (EPA OPPTS methods 830.6320 and 830.6313)