Octyl (R)-2-(4-chloro-2-methylphenoxy)propionate

Toxicity to soil macroorganisms except arthropods

Administrative data

Endpoint:

toxicity to soil macroorganisms except arthropods: short-term

Type of information:

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

Adequacy of study:

other information

Study period:

1989

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Reliable source.

Data source

Reference

Title:

The acute toxicity of U46 KV-Fluid (560 g/L of MCPP acid as dimethylamine salt) to Eisenia fetida

Author:

Adema & Roza

Year:

1989

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 207 (Earthworm, Acute Toxicity Tests)

Deviations:

not specified

GLP compliance:

not specified

Test material

Test material information

Constituent 1

Reference substance name:

66423-09-4

Cas Number:

66423-09-4

IUPAC Name:

66423-09-4

Constituent 2

Reference substance name:

Mecoprop-P dimethylamine salt

IUPAC Name:

Mecoprop-P dimethylamine salt

Constituent 3

Reference substance name:

MCPP-P DMA

IUPAC Name:

MCPP-P DMA

Constituent 4

Reference substance name:

R-(+)-2-(4-chloro-2-methylphenoxy)-propionic acid, dimethylamine salt

IUPAC Name:

R-(+)-2-(4-chloro-2-methylphenoxy)-propionic acid, dimethylamine salt

Details on test material:

Purity: not specified

Test organisms

Test organisms (species):

Eisenia fetida

Animal group:

annelids

Details on test organisms:

average weight at the beginning of the test 0.59 g +/- 0.13 g (n = 40)

Study design

Study type:

laboratory study

Substrate type:

artificial soil

Limit test:

no

Total exposure duration:

14 d

Test conditions

Test temperature:

21°C

pH:

5.7

Moisture:

50 - 55 % %

Nominal and measured concentrations:

nominal: 0, 10, 32, 100, 320 and 1000 mg a.i./kg soil

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

14 d

Dose descriptor:

LC50

Effect conc.:

988 mg/kg soil dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Effect concentrations 2

Duration:

14 d

Dose descriptor:

NOEC

Effect conc.:

100 mg/kg soil dw

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Any other information on results incl. tables

For Mecoprop-P dimethylamine salt (MCPP-P DMA) the 14d-LC50 was calculated to be 1764 mg/kg dry soil, corresponding to 988 mg/kg dry soil for Mecoprop-P acid (MCPP-P acid).

Within 14 days of exposure, no worm died at 571 g test substance/kg soil corresponding to 320 mg/kg for Mecoprop-P acid (MCPP-P acid), but they were wetter than the worms of the control and very sluggish.

The NOEC was determined to be 179 mg/kg soil for Mecoprop-P dimethylamine salt (MCPP-P DMA) corresponding to 100 mg/kg soil for Mecoprop-P acid (MCPP-P acid).

Applicant's summary and conclusion

Validity criteria fulfilled:

not specified

Remarks:

expected to be valid source

Conclusions:

For Mecoprop-P acid (MCPP-P acid), the hydrolysis product of Mecoprop-P n-octyl ester, a 14d-LC50 of 988 mg/kg dry soil and a 14d-NOEC of 100 mg/kg dry soil were determined on the earthworm Eisenia fetida.

Executive summary:

Mecoprop-P n-octyl ester hydrolyses rapidly in natural water. Therefore, the hydrolysis product Mecoprop-P acid (MCPP-P acid) was used for further assessment of Mecoprop-P n-octyl ester with respect to toxicity on terrestrial macroorganisms.

 

In a test system according to the OECD Guideline 207 for Mecoprop-P acid (MCPP-P acid) a 14d-LC50 of 988 mg/kg dry soil and a 14d-NOEC of 100 mg/kg dry soil was obseved on the earthworm Eisenia fetida.