Esterase, aryl

Acute Toxicity: oral

Administrative data

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2010

Report date:

2010

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

EPA OPPTS 870.1100 (Acute Oral Toxicity)

Deviations:

yes

Remarks:

Test article characterization, provided by Sponsor, was not conducted according to GLP; however, it was conducted under Good Manufacturing Practices.

Test guideline 2

Qualifier:

according to guideline

Guideline:

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

Deviations:

yes

Remarks:

Test article characterization, provided by Sponsor, was not conducted according to GLP; however, it was conducted under Good Manufacturing Practices.

GLP compliance:

yes

Test type:

up-and-down procedure

Limit test:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Active enzyme protein of Esterase, aryl (EC no. 232-884-0, CAS no. 9032-73-9, EC name: arylesterase, Enzyme Class no. 3.1.1.2)

Molecular formula:

Not applicable, see remarks

IUPAC Name:

Active enzyme protein of Esterase, aryl (EC no. 232-884-0, CAS no. 9032-73-9, EC name: arylesterase, Enzyme Class no. 3.1.1.2)

Constituent 2

Reference substance name:

Protein as a constituent of enzyme deriving from the fermentation or extraction process

Molecular formula:

Not available

IUPAC Name:

Protein as a constituent of enzyme deriving from the fermentation or extraction process

Constituent 3

Reference substance name:

Inorganic salts as a constituent of enzyme deriving from the fermentation or extraction process

Molecular formula:

Not available. See remarks.

IUPAC Name:

Inorganic salts as a constituent of enzyme deriving from the fermentation or extraction process

Constituent 4

Reference substance name:

Carbohydrates constituent of enzyme deriving from the fermentation or extraction process

Molecular formula:

Not available. See remarks.

IUPAC Name:

Carbohydrates constituent of enzyme deriving from the fermentation or extraction process

Constituent 5

Reference substance name:

Lipids as a constituent of enzyme deriving from the fermentation or extraction process

Molecular formula:

Not available. See remarks.

IUPAC Name:

Lipids as a constituent of enzyme deriving from the fermentation or extraction process

Test material form:

solid: granular

Details on test material:

- Substance type: UVCB
- Physical state: Granular

Test animals

Species:

rat

Strain:

Sprague-Dawley

Sex:

female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Ace Animals, Boyertown, PA
- Females (if applicable) nulliparous and non-pregnant: yes
- Age at study initiation: 8-9 weeks
- Weight at study initiation: 201-219 g
- Fasting period before study: 16-20 hours before dosing
- Housing: Individually housed in suspended stainless steel cages. Paper bedding was placed beneath the cages and changed at least 3x a week.
- Diet (e.g. ad libitum): ad libitum
- Water (e.g. ad libitum): ad libitum
- Acclimation period: 5 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): Temperature controlled; specific temperature range not reported
- Photoperiod (hrs dark / hrs light): 12 hour light/dark cycle

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

water

Details on oral exposure:

The test material was mixed with distilled water to make a 25% solution. The dose was based on the dry weight of the test substance.

Doses:

5000 mg/kg

No. of animals per sex per dose:

3 females

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: Observed at 15 min, 1, 2, and 4 hr, and then once daily for 14 days. All animals were observed 2x daily for mortality. Body weights were recorded at pretest, weekly and at termination.
- Necropsy of survivors performed: yes

Results and discussion

Effect levels

Key result

Sex:

female

Dose descriptor:

LD50

Effect level:

> 5 000 mg/kg bw

Based on:

test mat.

Mortality:

All animals survived.

Clinical signs:

other: No clinical signs were observed during the study.

Gross pathology:

Necrosopy results were normal.

Applicant's summary and conclusion

Interpretation of results:

GHS criteria not met

Conclusions:

In this study, the LD50 of the test substance is greater than 5000 mg/kg of body weight in female rats.

Executive summary:

This study was carried out in accordance with OPPTS 870.1100 and OECD 425 to determine the potential toxicity of the test substance orally. Initially, one female rat was dosed with 5000 mg/kg of body weight. Since the animal survived, two additional female rats were dosed at the same concentration. The rats were observed at 15 min, 1, 2, and 4 hours, and once daily for 14 days for toxicity and pharmacological effects. Body weights were recorded pretest, weekly, and at the termination of the study. All animals were examined for gross pathology.

All animals survived the 5000 mg/kg dose. There were no abnormal physical signs during the observation period and all body weights were normal. The necropsy results were normal as well. Therefore, in this study, the LD50 of the test substance is greater than 5000 mg/kg of body weight in female rats.