Lysozyme, hydrochloride

Acute Toxicity: oral

Administrative data

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From November 21, 2001 to January 02, 2002

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Test conducted following internationally accepted testing guidelines and performed according to the GLP.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2002

Report date:

2002

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

EPA OPPTS 870.1100 (Acute Oral Toxicity)

Deviations:

yes

Remarks:

protocol devation from 5 males and 5 females did not affect quality or outcome of study

GLP compliance:

yes

Test type:

standard acute method

Limit test:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Lysozyme, hydrochloride

EC Number:

232-954-0

EC Name:

Lysozyme, hydrochloride

Cas Number:

9066-59-5

Molecular formula:

C616H963N193O182S10 x HCl

IUPAC Name:

Lysozyme, hydrochloride

Test animals

Species:

rat

Strain:

Sprague-Dawley

Sex:

male/female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Specie & strain: Albino rat; Sprague-Dawley.
- Justification of Species: the rat is a rapresentative rodent species preferred by various regulatory agencies for use in an acute oral study.
- Source: Texas Animal Specialities, Humble, TX.
- Age at study initiation: 51 days males and 22 days.
- Weight at study initiation: males: 181 - 326 g; females: 199-218 g.
- Housing: 1 per cage.
- Cage type: suspended, wire bottom, stainless steel.
- Diet: PMI Feeds Inc.TM Formulab #5008; available ad libitum except for approximately 16 hours before dosing.
- Water: municipal water supply analyzed by TNRCC Water Utilities Division; available ad libitum from automatic water system.
- Quarantine period: 5 days.

ENVIRONMENTAL CONDITIONS
Set to maintain
- Temperature: 22 ± 3 °C.
- Humidity: 30 - 70 %.
- Air changes: 10-12 air change/hour.
- Photoperiod: 12 hours light/dark cycle.

IN-LIFE DATES
Animlas born in October 01 and 15, 2001. They were received by the laboratory at November 21 and December 06 and were treated with the test substance on December 19. The in-life portion of the study was termined on January 02, 2002.

No contaminants were expected to have been present in the feed or water which would have interfered with or affected the results of the study.

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

other: citric acid

Details on oral exposure:

TEST SUBSTANCE PREPARATION and ADMINISTRATION
The test substance was mixed with citric acid to produce a 40 % w/v concentration.

An individual dose was calculated for each animal based on its fasted body weight and administered by gavage at a volume of 12.6 ml/kg.
Each dose was administered using an appropriately sized singe and stainless steel ball-tipped intubation needle. The animals were returned to their cages immediately after dosing.

Doses:

5050 mg/kg (12.6 ml/kg).

No. of animals per sex per dose:

6 males and 4 females (nulliparous and non-pregnant) for a single fixed dose.

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: observations for mortality and clinical/behavioral signs of toxicity were made at least three times on the day of dosing (Day 0) and at least once daily thereafter for 14 days. Individual body weights were recorded just prior to dosing and on Days 7 and 14.
- Necropsy of survivors performed: yes; on Day 14 after dosing, each animal was euthanized by an overdose of CO2. All study animals were subjected to gross necropsy and all abnormalities were recorded.

Results and discussion

Effect levels

Sex:

male/female

Dose descriptor:

LD50

Effect level:

> 5 050 mg/kg bw

Based on:

test mat.

Mortality:

There was no mortality during the study. The estimated acute oral LD50, as indicated by the data, was determined to be greater than 5050 mg/kg.

Clinical signs:

other: Clinical signs included activity decrease, piloerection and respiratory chirp in both sexes, and diarrhea and sensitivity to touch in males. Animals were asymptomatic by Day 1.

Gross pathology:

The gross necropsy conducted at termination of the study revealed no observable abnormalities.

Any other information on results incl. tables

Reactions and Severity	Time after Treatment
	hours			days
MALES	1	2	4	1	2	3	4	5	6	7	8	9	10	11	12	13	14
Activity decrease	6	6	5	0	0	0	0	0	0	0	0	0	0	0	0	0	0
Sensitive to touch	1	1	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0
Diarrhea	1	1	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0
Piloerection	0	6	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0
Respiratory chirp	0	0	1	0	0	0	0	0	0	0	0	0	0	0	0	0	0
FEMALES
Respiratory chirp	1	1	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0
Activity decrease	4	4	1	0	0	0	0	0	0	0	0	0	0	0	0	0	0
Piloerection	0	4	0	0	0	0	0	0	0	0	0	0	0	0	0	0	0

Applicant's summary and conclusion

Interpretation of results:

not classified

Remarks:

Migrated information according to the CLP Regulation Criteria used for interpretation of results: EU

Conclusions:

LD50 is greater than 5050 mg/kg bw in males and females

Executive summary:

The test substance was evaluated for its acute oral toxicity potential in albino rats when administered as a single gavage dose at a level of 5050 mg/kg bw to males and females. No mortality occurred during the study. Clinical signs included activity decrease, diarrhea, piloerection, respiratory chirp and sensitivity to touch, which were no longer evident by Day 1. There was no effect on body weight gain. The gross necropsy conducted at termination of the study revealed no observable abnormalities.

Conclusion

The acute oral LD50 was determined to be greater than 5050 mg/kg bw