D-tetramethrin

Explosiveness

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

explosive properties of explosives

Type of information:

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

Adequacy of study:

key study

Justification for type of information:

1. HYPOTHESIS FOR THE ANALOGUE APPROACH
The source substance is the racemic form of the target substance d-tetramethrin. Tetramethrin does consist of 50% d- and l-form, and both do exist as cis and trans isomers. Hence, the target substance does consist of d-cis-tetramethrin, d-trans-tetramethrin, l-cis-tetramethrin and l-trans-tetramethrin, whereas the target substance only contains the first two (i.e. d-cis-tetramethrin, d-trans-tetramethrin).
Both, the source as well as the target substance, do have a cis/trans ratio of approximately 1/4 and obviously do share same molecular mass and other properties. Thus, the source substance by definition does contain ~50% of the d-form and the l-form is not expected to be significantly different with respect to its explosivity behaviour. Neither did the test item tetramethrin techn. showed sensitivity to impact, friction or thermal stress and thus was tested negative for explosive properties. Thus, no further testing was required and the substance is considered non-explosive, and it can be reasonably assumed that the d-tetramethrin will not be critical with respect to explosivity.
2. SOURCE AND TARGET CHEMICAL(S) (INCLUDING INFORMATION ON PURITY AND IMPURITIES)
The d-tetramethrin with a purity > 80 % does contain its corresponding l-form as an impurity in the range of < 7%, other impurities from the manufacturing process are individually below 1% (w/w) each. The source substance that has been tested was having a purity of approx. 98% as tetramethrin with a cis/trans ratio of 1/4 and a d-form/l-form ratio of ~50/50.
3. ANALOGUE APPROACH JUSTIFICATION
Source and Target substance do share identical structure and molecular weight, only differentiating by the fact that the source substance is a racemic mixture, whereas the target substance represents almost pure d-form. Thus, physico-chemical parameters, not being affected significantly by stereochemistry, are fully comparable, thus justifying using available data on explosive properties on the racemic form for supportive read-across to the d-enantiomer.
4. DATA MATRIX
Composition comparison
D-tetramethrin (target) tetramethrin (source)
D-trans tetramethrin 70 - 80% 40 – 50%
D-cis tetramethrin 10 - 20% 7 – 11 %
L-trans tetramethrin 0 – 5% 35 – 40%
L-cis tetramethrin 0 – 2% 7 – 11%

Reason / purpose for cross-reference:

read-across source

Parameter:

thermal sensitivity - Koenen test: diameter of the orifice plate

Remarks on result:

not thermal sensitive if heated under defined confinement

Parameter:

sensitiveness to impact: impact energy (J)

Remarks on result:

other: no sensitive to impact using an impact energy of 90 J

Parameter:

sensitiveness to friction: friction load (N)

Remarks on result:

not sensitive to friction using a friction load of 360 N

Interpretation of results:

GHS criteria not met

Conclusions:

The source substance being racemic tetramethrin has been tested for explosive properties by shock, friction and thermal stress, not found being explosive and thus it can be reasonably concluded that also d-tetramethrin does not have explosive properties.

Reference 2

Endpoint:

explosive properties of explosives

Data waiving:

study scientifically not necessary / other information available

Justification for data waiving:

the study does not need to be conducted because there are no chemical groups present in the molecule which are associated with explosive properties

Description of key information

From the experimental data obtained, it can be concluded that the sample of racemic tetramethrin (technical grade) does not exhibit explosive properties, according to the criteria of the guideline A.14 in Official Journal L 283. Accordingly, d-tetramethrin is also considered non-explosive. Furthermore, there are no chemical groups present in the molecule which are associated with explosive properties.

Key value for chemical safety assessment

Explosiveness:

non explosive

Justification for classification or non-classification

Based on results from a study for explosive properties the substance was tested negative and consequently does not require classification for explosive properties according to CLP (Regulation EC No. 1272/2008).