Diethylzinc

Endpoint summary

Key value for chemical safety assessment

Genetic toxicity in vitro

Description of key information

Corrosive. Flammable in air at room temperature. Zinc alkyls are highly reactive substances both in air and in contact to water, causing explosive or flammable situations as explained below. Thus, this test is technically not feasible to conduct and is scientifically unjustified. Most of the chemistry of organozinc compounds can be explained in terms of the polarization of the zinc carbon bond, the high energy of highest occupied molecular orbital (HOMO) and relatively low-lying vacant 4s- and 4p-orbitals. These electronic properties render this class of compounds highly nucleophilic and easily oxidizable, which, for example, reflects in their high flammability in the air. Short chain zinc alkyls ignite spontaneously on contact with air and therefore are classified pyrophoric under UN transport classification. The flammability of Zn alkyls decreases on increasing bulkiness of the alkyl groups. Reactions of zinc alkyls with liquids are in some cases explosion like. Most prominent example is reaction with water, which liberates for short chain alkyls highly flammable gases within seconds (alkyl groups with five carbon atoms and less).Low-lying vacant 4s- and 4p-orbitals are responsible for mild Lewis acidity of organozinc compounds. Driven by nucleophilic power of their alkyl groups organozinc compounds add to aldehydes, activated ketones and some other unsaturated electrophiles. High polarity of the Zn-C bond makes Zn alkyls rather good deprotonating agents.

Short description of key information:

Corrosive. Flammable in air at room temperature. According to the Annex VII Standard Information Requirements for REACH, an in vitro gene mutation study in bacteria is required. A specific rule for adaptation for not conducting this test is not stated. However, there are mitigating circumstances as to why this test cannot be conducted.

Link to relevant study records

Reference

Reference 1

Endpoint:

in vitro gene mutation study in bacteria

Data waiving:

study technically not feasible

Justification for data waiving:

other:

Conclusions:

Corrosive. Flammable in air at room temperature. Thus, exposure of bacteria in an in vitro mutagenicity test to zinc alkyls would not generate meaningful data, and no mutagenicity study is required for this substance.

Executive summary:

Corrosive. Flammable in air at room temperature. Thus, exposure of bacteria in an in vitro mutagenicity test to zinc alkyls would not generate meaningful data, and no mutagenicity study is required for this substance.

Reference 2

Endpoint:

in vitro cytogenicity / chromosome aberration study in mammalian cells

Data waiving:

study technically not feasible

Justification for data waiving:

other:

Conclusions:

Corrosive. Flammable in air at room temperature. Thus, exposure of bacteria in an in vitro mutagenicity test to zinc alkyls would not generate meaningful data, and no mutagenicity study is required for this substance.

Executive summary:

Corrosive. Flammable in air at room temperature. Thus, exposure of bacteria in an in vitro mutagenicity test to zinc alkyls would not generate meaningful data, and no mutagenicity study is required for this substance.

Reference 3

Endpoint:

in vitro gene mutation study in mammalian cells

Data waiving:

study technically not feasible

Justification for data waiving:

other:

Conclusions:

Corrosive. Flammable in air at room temperature. Thus, exposure of bacteria in an in vitro mutagenicity test to zinc alkyls would not generate meaningful data, and no mutagenicity study is required for this substance.

Executive summary:

Corrosive. Flammable in air at room temperature. Thus, exposure of bacteria in an in vitro mutagenicity test to zinc alkyls would not generate meaningful data, and no mutagenicity study is required for this substance.

Endpoint conclusion

Endpoint conclusion:

no study available

Justification for classification or non-classification

Corrosive. Flammable in air at room temperature. According to the Annex VII Standard Information Requirements for REACH, an in vitro gene mutation study in bacteria is required. A specific rule for adaptation for not conducting this test is not stated. However, there are mitigating circumstances as to why this test cannot be conducted.