Oxalonitrile

Toxicity to soil macroorganisms except arthropods

Link to relevant study record(s)

Reference

Endpoint:

toxicity to soil macroorganisms except arthropods, other

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 207 (Earthworm, Acute Toxicity Tests)

GLP compliance:

yes

Test organisms (species):

Eisenia fetida

Animal group:

annelids

Study type:

laboratory study

Substrate type:

artificial soil

Remarks:

The artificial soil was obtained by mixing 12.5% peat, 5% vermiculite, 20% top soil and 62.5% Florida sand

Total exposure duration:

14 d

Test temperature:

20 +/- 2 °C

pH:

5.9

Moisture:

35 %

Details on test conditions:

One litre capacity soil jars were induced with cyanogen in the lab according to the study protocol. All jars were capped with butyl rubber septa. All ethanedinitrile treated jars were ventilated after 24 hours of application. The jars were opened after 12 hours of ventilation to count the number of live and dead earthworms. After counting, all materials were replaced in the jars. The jars were put under the light at room temperature 20 ± 2o C, soil moisture was adjusted when necessary, and mortality rate was recorded again on days 7 and 14.

Nominal and measured concentrations:

Seven rates at 0, 0.01, 0.1, 1.0, 10, 100 and 1,000 mg ethanedinitrile kg-1 artificial soil were applied through the septa into the jar.

Key result

Duration:

14 d

Dose descriptor:

LC50

Effect conc.:

5 mg/kg soil dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Executive summary:

Earthworm acute toxicity tests (artificial soil test) for Cyanogen (C2N2) using OECD 207 test method

 

This study was performed to determine the effects of ethanedinitrile on earthworm acute toxicity to comply with the requirements for an ecotoxicology study on plant protection products ‘Earthworm, Acute toxicity test’. The study was conducted according to the OECD Guideline for the testing of chemicals, Earthworm, Acute Toxicity Test: Guideline 207, the OECD Guideline for the testing of chemicals.Eisenia foetidaspecies was studied in artificial soil under laboratory conditions.

Seven rates at 0, 0.01, 0.1, 1.0, 10, 100 and 1,000 mg ethanedinitrile kg^-1artificial soil were applied through the septa into the jar. The artificial soil was obtained by mixing 12.5% peat, 5% vermiculite, 20% top soil and 62.5% Florida sand. Soil pH was adjusted to 5.9 and moisture was maintained at 35%.

One litre capacity soil jars were induced with cyanogen in the lab according to the study protocol. All jars were capped with butyl rubber septa. All ethanedinitriletreatedjars were ventilated after 24 hours of application. The jars were opened after 12 hours of ventilation to count the number of live and dead earthworms. After counting, all materials were replaced in the jars. The jars were put under the light at room temperature 20 ± 2^oC, soil moisture was adjusted when necessary, and mortality rate was recorded again on days 7 and 14. The average weight of live earthworms at the beginning and at the end of the experiment was recorded. Each treatment was replicated four times. The recoveries of earthworm up to 1 mg ethanedinitrilekg^-1soil application levels were 100%. 

The mortality rate was expressed and reported as median lethal concentration (LC₅₀).

There was no evidence that ethanedinitrile affected earthworm average body weight at 1 mg C₂N₂Kg^-1or lower rates. There were no distinct behavioural change or injury symptoms observed for the live earthworms after treatment.

All earthworms died in the 10 mg ethanedinitrilekg^-1soil treatment level on day 0 of ethanedinitrile application. Over the 14-day observation period, no earthworm was affected by ethanedinitrile application at 1 mg ethanedinitrile kg^-1soil or less. From the total number of mortalities recorded the LC₁₀₀value is 10 mg ethanedinitrile kg^-1soil. 24-hour LC₅₀is 5 mg ethanedinitrile kg^-1soil.

Description of key information

This study was performed to determine the effects of ethanedinitrile on earthworm acute toxicity to comply with the requirements for an ecotoxicology study on plant protection products ‘Earthworm, Acute toxicity test’. The study was conducted according to the OECD Guideline for the testing of chemicals, Earthworm, Acute Toxicity Test: Guideline 207, the OECD Guideline for the testing of chemicals.Eisenia foetidaspecies was studied in artificial soil under laboratory conditions.

One litre capacity soil jars were induced with cyanogen in the lab according to the study protocol. All jars were capped with butyl rubber septa. All ethanedinitrile treated jars were ventilated after 24 hours of application. The jars were opened after 12 hours of ventilation to count the number of live and dead earthworms. After counting, all materials were replaced in the jars. The jars were put under the light at room temperature 20 ± 2o C, soil moisture was adjusted when necessary, and mortality rate was recorded again on days 7 and 14. The average weight of live earthworms at the beginning and at the end of the experiment was recorded. Each treatment was replicated four times. The recoveries of earthworm up to 1 mg ethanedinitrile kg-1 soil application levels were 100%. The mortality rate was expressed and reported as median lethal concentration (LC50). There was no evidence that ethanedinitrile affected earthworm average body weight at 1 mg C2N2 Kg-1 or lower rates. There were no distinct behavioural change or injury symptoms observed for the live earthworms after treatment. All earthworms died in the 10 mg ethanedinitrile kg-1 soil treatment level on day 0 of ethanedinitrile application. Over the 14-day observation period, no earthworm was affected by ethanedinitrile application at 1 mg ethanedinitrile kg-1 soil or less. From the total number of mortalities recorded the LC100 value is 10 mg ethanedinitrile kg-1 soil. 24-hour LC50 is 5 mg ethanedinitrile kg-1 soil. Exposure of soil organisms is not expected as the fumigant is used for treatment of wood in enclosed spaces. The only emission of the active substance to the air will occur during ventilation of the fumigated wood. The substance will be dispatched in the air and will get quickly diluted due to its high volatility. The substance will stay in the air based on its physical and chemical properties and will not transfer to other environmental compartments such as soil and water as confirmed by models in the environmental fate part of dossier.

Key value for chemical safety assessment

Short-term EC50 or LC50 for soil macroorganisms:

5 mg/kg soil dw