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

Toxicity to birds

Administrative data

Endpoint:

short-term toxicity to birds: acute oral toxicity test

Type of information:

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

Adequacy of study:

other information

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Reliable source.

Data source

Reference

Reference Type:

other: unpublished study

Title:

Unnamed

Year:

1992

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

EPA OPP 71-1 (Avian Acute Oral Toxicity Test)

Deviations:

not specified

GLP compliance:

yes

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:

Mecoprop-P dimethylamine salt (MCPP-P DMA): 65.62 %, eqivalent to 54.23 % Mecoprop-P acid (MCPP-P acid)

Dose method:

gavage

Test organisms

Test organisms (species):

Colinus virginianus

Details on test organisms:

males/females, 1/1; 22 weeks old

Study design

Limit test:

no

Total exposure duration (if not single dose):

14 d

Results and discussion

Effect levels

Duration (if not single dose):

14 d

Dose descriptor:

LD50

Effect level:

497 mg/kg bw

Conc. / dose based on:

test mat.

Basis for effect:

mortality

Any other information on results incl. tables

Chalky diarrhea was noted in all groups, however, the animals recovered after day 2 at 191 and 318 mg/kg bw dose level. Lethargy and hypersalivation were observed at the highest dose level. Mortality occurred from 529 mg/kg bw and all birds died at the two highest dose levels. LD50 was determined as 602 mg MCPP-P DMA/kg bw eqivalent to 497 mg MCPP-P acid/kg bw.

The body weight was reduced at 529 mg/kg bw concurrent with reduced feed consumption. Gross pathological findings that could be related to the test substance were intestinal hemorrhages and fluid filled crop in dead animals. NOEL was 263 mg MCPP-P acid/kg bw based on body weight, but including the observstion of transient diarrhea it would be < 158 mg MCPP-P acid/kg bw.

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-LD50 of 497 mg/kg bw was determined in a oral single-dose study on Bobwhite quail.

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 birds.

 

In an oral single-dose test, according to the EPA OPP 71 -1, for Mecoprop-P acid (MCPP-P acid) a 14d-LD50 of > 497 mg/kg bw was obseved on Bobwhite quail.