Dimethyl disulphide

Toxicity to terrestrial arthropods

Description of key information

Several tests have been launched for assessing DMDS toxicity to beneficial arthropods.

- An acute toxicity study, carried out according to test procedures in accordance with OECD guideline studies, reveal 48-hour LD₅₀ greater than 100 µg a.i./bee for Apis mellifera (Honeybee). DMDS is therefore considered as non toxic to bees.

- A reproduction toxicity on Hypoaspis aculeifer, carried out according to drafted OECD guideline, gives a LC₅₀16d of 207.7 mg/kg soil dw, based on mortality. Based on reproduction, EC₅₀ 16d is of 100.9 mg/kg soil dw. NOEC is of 31.6 mg/kg soil dw, based on mortality and on reproduction.

- A reproduction toxicity study of DMDS toFolsomia candida(collembola) was carried out by Moser according to the ISO 11267 standard. Based on the results of this study, the 28-days NOEC based on reproduction was determined to be 10 mg/kg soil dw

- A toxicity on Poecilus cupreus (Carabid beetle), carried out according to Heimbach method, gives a 14 days NOEC greater than 1000 mg/kg soil dw, based on mortality. 14-days LC₅₀ value is not calculated.

Key value for chemical safety assessment

Short-term EC50 or LC50 for soil dwelling arthropods:

207.7 mg/kg soil dw

Long-term EC10, LC10 or NOEC for soil dwelling arthropods:

10 mg/kg soil dw

Additional information

Toxicity to bee:

In 2008, acute contact toxicity of DMDS to Apis mellifera (Hymenoptera, honeybees) has been investigated by Porch and Krueger in a GLP study and through OECD guideline 214. The duration of the study was of 48 hours.

The 48-hour LD₅₀ value for Apis mellifera exposed to dimethyl disulfide was determined to be greater than the nominal dose of 100 µg a.i./bee.

The LD₅₀ value was used to classify the test substance according to the toxicity categories of Atkins. Thus dimethyl disulfide is classified as relatively non-toxic to honey bees according to the toxicity categories of Atkins.

Toxicity to Hypoaspis aculeifer:

In 2006, a reproduction toxicity study of DMDS to Hypoaspis aculeifer was carried out by Moser according to the OECD Guideline Proposal for the Testing of Chemicals "Predatory mite reproduction test in soil (Hypoaspis (Geolaelaps) aculeifer)".

Based on the results of this study, the 16-days LC₅₀ value for Hypoaspis aculeifer exposed to dimethyl disulfide was determined to be

207.7 mg/kg soil dw, based on mortality. Based on reproduction, EC₅₀ -16d was of 100.9 mg/kg soil dw. NOEC was of 31.6 mg/kg soil dw, based on mortality and on reproduction.

Toxicity toFolsomia candida:

In 2006, a reproduction toxicity study of DMDS to Folsomia candida (collembola) was carried out by Moser according to the ISO 11267 standard.

Based on the results of this study, the 28-days NOEC based on reproduction was determined to be 10 mg/kg soil dw.

Toxicity to Poecilus cupreus:

In 2006, a toxicity study of DMDS to Poecilus cupreus (Carabid beetle) was carried out by Moser according to "Heimbach et al. 2000 method for testing effects of plant protection products on the carabid beetle, Poecilus cupreus (Coleoptera, Carabidae) under laboratory and semi-field conditions".

Based on the results of the study, the 14-days LC₅₀ value for Poecilus cupreus exposed to dimethyl disulfide could not be calculated since the mortality observed with the test item was not higher than 3.3%. NOEC was determined to be >= 1000 mg/kg soil dw, based on mortality, and LOEC > 1000 mg/kg soil dw.