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Toxicological information

Acute Toxicity: oral

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Administrative data

Endpoint:
acute toxicity: oral
Type of information:
experimental study
Adequacy of study:
key study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
guideline study with acceptable restrictions

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1996
Report Date:
1996

Materials and methods

Test guidelineopen allclose all
Qualifier:
according to
Guideline:
OECD Guideline 401 (Acute Oral Toxicity)
Deviations:
no
Qualifier:
according to
Guideline:
EPA OTS 798.1175 (Acute Oral Toxicity)
Deviations:
no
GLP compliance:
yes
Test type:
standard acute method
Limit test:
no

Test material

Reference
Name:
Unnamed
Type:
Constituent
Test material form:
liquid
Details on test material:
- Name of test material (as cited in study report): Methyltin tris (2-ethylhexylthioglycolate)
- Lot/batch No.: 1706-151
- Storage condition of test material: room temperature

Test animals

Species:
rat
Strain:
Sprague-Dawley
Sex:
male/female
Details on test animals and environmental conditions:
TEST ANIMALS
- Source: Harlan Sprague-Dawley, Inc., Indianapolis, IN
- Age at study initiation: naive young
- Weight at study initiation: 211-319 g for both sexes
- Fasting period before study: overnight prior to dosing
- Housing: housed in groups of 5
- Diet (e.g. ad libitum): ad libitum
- Water (e.g. ad libitum): ad libitum
- Acclimation period: at least 5 days prior to being used in the test

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 18-26 degrees C
- Humidity (%): 30-70%
- Photoperiod (hrs dark / hrs light): 12 hours light/ 12 hours dark

IN-LIFE DATES: From: July 30, 1996 To: August 22, 1996

Administration / exposure

Route of administration:
oral: gavage
Vehicle:
unchanged (no vehicle)
Doses:
0.50, 0.80, 1.25 and 3.15 g/kg
No. of animals per sex per dose:
5
Control animals:
no
Details on study design:
- Duration of observation period following administration: 14 days (or other?) 14 days
- Frequency of observations and weighing: observed frequently for signs of systemic toxicity and mortality on the day of test initiation and at least twice daily thereafter; Body weights were measured at test initiation, Day 7 and post-mortem.
- Necropsy of survivors performed: yes
- Other examinations performed: clinical signs, body weight, gross pathology
Statistics:
LD50 values and 95 % confidence limits were calculated using the Litchfield and Wilcoxon method (1949)

Results and discussion

Preliminary study:
No data
Effect levels
Key result
Sex:
male/female
Dose descriptor:
LD50
Effect level:
880 mg/kg bw
95% CL:
> 670 - < 1 150
Remarks on result:
other: reported as g/kg bw; results were converted to mg/kg bw
Mortality:
0.50 g/kg bw: Males: no mortality; Females: 1 dead at 24 h
0.80 g/kg bw: Males: no mortality; Females: 2 dead at 24 h, 2 dead at 48 h
1.25 g/kg bw: Males: 3 dead at 24 h; Females: 4 dead at 24 h, 1 dead at 48 h
3.15 g/kg bw: Males: 5 dead at 24 h; Females: 5 dead at 24 h
Clinical signs:
Clinical observations included depression, comatose, piloerection, eye squinting, hunched posture, labored breathing, ataxia, fecal stains, urine stains, and masticatory movement
Body weight:
Body weight generally increased for all animals in the 0.50 and males in the 0.80 g/kg dose groups. Most males in the 1.25 did not gain weight. At the 3.15 g/kg dose, 3 of 5 males gained weight. A slight decrease was noted in the body weights of females in the dose groups >=0.8 g/kg.
Gross pathology:
Gross necropsy results (for animals that died during the test):
Lungs: pale, reddened, or mottled
Liver: pale or mottled with darkened edges, or white/blanched areas
Spleen: pale, darkened, or mottled
Pancreas: darkened
Kidneys: enlarged, pale, and/or congested
Stomach: distended
Intestines: reddened, distended, and contained a viscous yellow/orange fluid
Bladder: contained a red fluid, external staining noted

No gross pathological changes were noted in the surviving animals.
Other findings:
Signs of systemic toxicity increased with increasing dose levels.

Applicant's summary and conclusion

Interpretation of results:
other: Classified as Category 4 in accordance with EU criteria
Conclusions:
LD50 880 mg/kg bw
Executive summary:

The acute oral toxicity of undiluted Methyltin tris (2­ethylhexylthioglycolate) was evaluated in compliance with the conditions specified in the regulation for the enforcement of the Federal Insecticide, Fungicide, and Rodenticide Act (40 CFR), the Toxic Substances Control Act (40 CFR) and OECD Guideline 401.

The test material was administered undiluted to groups of five male and five female Sprague Dawley rats at a dose level of 3.15 g/kg, 1.25 g/kg, 0.80 g/kg, and 0.50 g/kg. Following a single oral administration, the animals were observed for 14 days.

Based on the mortality observed, the acute oral LD50 value was calculated to be 0.88 g/kg with the 95% Confidence Limits of 0.67 g/kg and 1.15 g/kg. Clinical signs noted during the observation period included varying degrees of depression, comatose, piloerection, eye squinting, hunched posture, labored breathing, ataxia, fecal stains, urine stains, and masticatory movement. All surviving animals exhibited body weight gain at day 14. Gross necropsy findings for animals that died during the observation period included lungs pale, reddened, or mottled, liver mottled, liver pale and mottled with lower edge of lobes of liver darkened, areas of liver exhibit white blanching, areas of liver pale, spleen pale, darkened, or mottled, pancreas darkened, kidneys pale and/or congested, kidneys enlarged, stomach distended with gas, intestines reddened, intestines distended with gas, intestines contain a viscous yellow to orange fluid, urinary bladder contains a pale red fluid, and external staining. No gross pathological changes were noted in animals that survived the observation period.