Bromacil

Acute Toxicity: oral

Administrative data

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

January 2007

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2007

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 425 (Acute Oral Toxicity: Up-and-Down Procedure)

Test guideline 2

Qualifier:

according to guideline

Guideline:

EPA OPPTS 870.1100 (Acute Oral Toxicity)

GLP compliance:

yes (incl. QA statement)

Test type:

up-and-down procedure

Test material

Test material information

Constituent 1

Reference substance name:

Bromacil

EC Number:

206-245-1

EC Name:

Bromacil

Cas Number:

314-40-9

Molecular formula:

C9H13BrN2O2

IUPAC Name:

5-bromo-3-sec-butyl-6-methylpyrimidine-2,4(1H,3H)-dione

Specific details on test material used for the study:

Purity: 97.27%

Test animals

Species:

rat

Strain:

Sprague-Dawley

Remarks:

Crl:CD(SD)

Sex:

female

Details on test animals or test system and environmental conditions:

Animal rooms were maintained at a temperature of 18-26°C and a relative humidity of 30-70%.
Animal rooms were artificially illuminated (fluorescent light) on an approximate 12-hour light/dark cycle.

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

methylcellulose

Remarks:

0.5% aqueous

Doses:

(2 x) 175, (3 x) 550 and 1750 mg/kg

No. of animals per sex per dose:

6

Control animals:

no

Details on study design:

The rats were dosed one at a time at a minimum of 48-hour intervals. The rats were observed for mortality, body weight effects, and clinical signs for up to 14 days after dosing.

Results and discussion

Effect levels

Key result

Sex:

female

Dose descriptor:

LD50

Effect level:

550 mg/kg bw

Based on:

test mat.

Mortality:

Two of the three rats dosed at 550 mg/kg were sacrificed in extremis on the day of dosing or the day after dosing. These rats were considered in the same way as the rat that died. The rat dosed at 1750 mg/kg was found dead two days after dosing.

Clinical signs:

other: Clinical signs were observed up to two days after dosing in all rats except one rat dosed at 175 mg/kg and included lethargy, decreased muscle tone, ataxia, clear ocular discharge (lacrimation), high carriage, mydriasis, abnormal gait, tremors, slow breat

Gross pathology:

Gross findings were present in the rat administered 1750 mg/kg and one rat administered 550 mg/kg. These included stomach ulcer/erosion and skin stain in one rat (found dead, 1750 mg/kg); and skin stain in another rat (sacrificed in extremis, 550 mg/kg). No other gross findings were observed.

Applicant's summary and conclusion

Interpretation of results:

Category 4 based on GHS criteria

Conclusions:

Under the conditions of this study, the oral LD50 for bromacil was 550 mg/kg for female rats.