Propargite

Acute Toxicity: oral

Administrative data

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

26th July 1991 to 2nd September 1991

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1993

Report date:

1993

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

EPA OPP 81-1 (Acute Oral Toxicity)

Deviations:

no

Test guideline 2

Qualifier:

equivalent or similar to guideline

Guideline:

EPA OTS 798.1175 (Acute Oral Toxicity)

Deviations:

no

Test guideline 3

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 401 (Acute Oral Toxicity)

Deviations:

no

GLP compliance:

yes

Test type:

standard acute method

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

Propargite

EC Number:

219-006-1

EC Name:

Propargite

Cas Number:

2312-35-8

Molecular formula:

C19H26O4S

IUPAC Name:

propargite

Test material form:

liquid

Details on test material:

- Name of test material (as cited in study report): Omite® Technical
- Stability under test conditions: at least one year at room temperature
- Storage condition of test material: sealed container at room temperature

Test animals

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River Breeding Laboratories, Inc., Portage, Michigan, USA
- Age at study initiation: young adult
- Weight at study initiation: 203-278 g
- Fasting period before study: yes (approximately 18-20 hours)
- Housing: individual suspended wire-mesh cages
- Diet: Purina® Certified Rodent Chow® #5002 ad libitum
- Water: tap water ad libitum
- Acclimation: 7 days minimum

ENVIRONMENTAL CONDITIONS
- Temperature: 70-75 ºF
- Humidity: 54-86 %
- Photoperiod: 12 hours light/12 hours dark

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

unchanged (no vehicle)

Details on oral exposure:

RATIONAL FOR THE SELECTION OF THE STARTING DOSE
- A range-finding study was conducted in which groups of one male and one female were dosed at levels of 500, 1000, 2000, 3500 and 5000 mg/kg. The male dosed at 2000 mg/kg, the female dosed at 3000 mg/kg and all animals dosed at 5000 mg/kg died. Both animals dosed at 500 and 1000 mg/kg survived. Based on these results 2000 mg/kg was selected as the first dose level on the definitive study.

- Three groups of five male and five female rats were administered single doses at levels of 2000, 2800 and 3920 mg/kg. Dose levels were selected using a progression of 1.4.

Doses:

2000, 2800 and 3920 mg/kg bw (dose volumes of 1.8, 2.57 and 3.6 mL/kg respectively)

No. of animals per sex per dose:

Five

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: clinical observations at 1, 3 and 4 hours post-dose and twice daily thereafter; body weights at days -1, 0, 7 and 14 (and at death)
- Necropsy of survivors performed: yes

Results and discussion

Effect levels

Key result

Sex:

male/female

Dose descriptor:

LD50

Effect level:

2 800 mg/kg bw

Based on:

test mat.

95% CL:

>= 2 511 - <= 3 122

Mortality:

All mortalities occurred in the second week of the study (days 6- 11), during which the combined mortality was 0/10, 5/10 and 10/10 in the 2000, 2800 and 3920 mg/kg bw groups, respectively (see Table 1).

Clinical signs:

other: All animals displayed various signs of urogenital staining/matting. Abnormal defecation was observed in 28 animals, while 20 animals exhibited decreased urination. Hypoactivity was observed for 23 animals. The hindpaws and/or forepaws were red/swollen in

Gross pathology:

Findings of gross necropsy on animals that died during the study, included stomach abnormalities (thickened mucosa and red areas/contents), intestinal abnormalities (distended red with contents), reddened adrenal glands, red lungs, reddened pituitary, dark red prostate and red streaks in the bladder.

Any other information on results incl. tables

Table 1: Mortality

Dose level (mg/kg bw)	Male mortality	Female mortality	Total mortality
2000	0/5	0/5	0/10
2800	4/5	1/5	5/10
3920	5/5	5/5	10/10

Applicant's summary and conclusion

Interpretation of results:

other: Not classified in accordance with EU criteria

Conclusions:

The acute oral LD50 of the test material in rats was calculated to be 2800 mg/kg (95 % C.I. 2511-3122 mg/kg).

Executive summary:

The test material was administered once orally via gastric intubation to groups of five male and five female fasted albino rats at dose levels of 2000, 2800 and 3920 mg/kg. Mortality, clinical observations, body weights and gross necropsy findings were evaluated.

Clinical findings were generally noted throughout the study and in all dose groups. All animals had various urogenital staining. The majority of the animals had abnormal defecation and swollen hindpaw(s) and/or forepaw(s). The urogenital area appeared swollen on the majority of females. Essentially all males had a red and swollen penis and prepuce and the majority of animals in the 2000 and 2800 mg/kg groups had necrotic areas on the scrotum. Hypoactivity, wet and/or dried material on the forepaw(s), dried red material around the mouth, decreased urination and a red and swollen mouth were noted for approximately two-thirds of the animals. More than one-half of the animals had hair loss at the base of the tail. Approximately one-third of the animals had red and swollen ears and hypothermia. Eight animals were hypersensitive to the touch. Other clinical findings included rales, scabbing of the right and/or left ear, dried red material around the eye(s), ataxia, moist alopecia on the forepaw(s) and/or hindpaw(s), dried red abdominal staining, dehydration, prostration and greenish discolouration of the tissues in the urogenital area.

No mortality was observed in the 2000 mg/kg group. Five and ten deaths were observed in the 2800 and 3920 mg/kg groups respectively.

Twenty-four animals lost weight from day 0 to day 7; all surviving animals gained weight during the second week of the study.

G.I. abnormalities were noted for 14/15 animals that died and were considered to be due to the irritative properties of the test material. Dark red or reddened adrenal glands, a typical agonal or stress-related change, were observed for six animals that died. Five animals had bright red lungs and three animals were icteric. Other findings observed for one animals included a reddened pituitary gland, a dark red prostate gland and dark red streaks on the urinary bladder. 14/15 animals that died had external matting. Reddened forepaw(s) and/or hindpaw(s) were observed on six animals. Two animals had reddened ear(s) and a red and swollen penis. Scabbing on the forepaw and hair loss were each noted for one animal.

External surface findings were noted on all animals that were terminally necropsied. Various scabbing, hair loss and swelling were noted for approximately two-thirds of the animals. Approximately one-third of the animals had reddened hindpaw(s) and/or forepaw(s). Red nasal matting and a thickened mucosa in the stomach were noted for two animals each. One 2800 mg/kg male had small, soft testes. No other significant changes were observed at terminal necropsy.

The LD₅₀ was determined to be 2800 mg/kg (95 % C.I. 2511-3122 mg/kg).