Cetylpyridinium chloride

Acute Toxicity: oral

Administrative data

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

February 2005-May 2005

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Guideline study under GLP

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2005

Report date:

2005

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

Limit test:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Cetylpyridinium chloride

EC Number:

204-593-9

EC Name:

Cetylpyridinium chloride

Cas Number:

123-03-5

Molecular formula:

C21H38N.Cl

IUPAC Name:

cetylpyridinium chloride

Constituent 2

Reference substance name:

CPC

IUPAC Name:

CPC

Test material form:

solid: particulate/powder

Remarks:

migrated information: powder

Details on test material:

Test Substance Identification: Cetylpyridinium Chloride
Lot#: 00217966
Purity: 100.1% by assay
Test Substance Description: White powder
Date received: January 12, 2005
PSL Reference No: 050112-ID
Study Initiation Date: February 9, 2005

Test animals

Species:

rat

Strain:

Sprague-Dawley

Sex:

female

Details on test animals or test system and environmental conditions:

Housing: The animals were singly housed in suspended stainless steel caging with mesh floors. Litter paper was placed beneath the cage and was changed at least three times per week.
Animal Room Temperature Range: 20-23C
Photoperiod: 12-hour light/dark cycle
Acclimation Period: 21-28 Days
Food: Purina Rodent Chow #5012
Water: Filtered tap water was supplied ad-libitum by an automatic water dispensing system.

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

water

Details on oral exposure:

The test substance was administered as a 40% w/w mixture in distilled water using a stainless steel ball-tippd gavage needle attached to an appropriate syringe. Following administration, each animal was returned to its designated cage. Feed was replaced approximately 2-4 hours after dosing.

Doses:

95, 300 and 950 mg/kg

No. of animals per sex per dose:

3 females (1 animal for the low dose exposure)

Control animals:

no

Details on study design:

An acute oral toxicity test (Up and Down Procedure) was conducted with rats to determine the potential for Cetylpyridinium Chloride to produce toxicity from a single dose via the oral route.
Based on an estimate of the LD50 supplied by the Sponsor (300 mg/kg), a Main Test was conducted using a default starting dose level of 95 mg/kg which was administered to one healthy female rat by oral gavage. Following the Up and Down procedure, six additional animals were dosed at levels of 300 or 950 mg/kg. Females were selected for the test because they are frequently more sensitive to the toxicity of test compounds than males. All animals were observed for mortality, signs of gross toxicity, and behavioral changes at least once daily for up to 14 days after dosing. Body weights were recorded prior to administration and again on Days 7 and 14 (termination) after dosing or after death. Necropsies were performed on all animals.

Results and discussion

Effect levels

Sex:

female

Dose descriptor:

LD50

Effect level:

560.3 mg/kg bw

Based on:

test mat.

95% CL:

>= 300 - <= 950

Mortality:

3 deaths among 3 animals at 950 mg/kg Dose Level. Deaths occurred withing two days of test substance administration.
No deaths among one animal at 95 mg/kg Dose level and 3 animals at the 300 mg/kg Dose Level.

Clinical signs:

other: 95 mg/kg Dose Level (1 animal) There were no signs of gross toxicity, adverse pharmacologic effects, or abnormal behavior 300 mg/kg Dose level (3 animals) Following administration, two animals exhibited soft feces, reduced fecal volume, or piloerection. 9

Gross pathology:

95 mg/kg Dose level
No gross abnormalities were noted for this animal when necropsied
300 mg/kg Dose Level
No gross abnormalities were noted for any of the animals when necropsied
950 mg/kg Dose Level
Gross necropsy of the decedents revealed discoloration of the intestines and/or lungs and/or gaseous distention of the intestines.

Any other information on results incl. tables

Under the conditions of this study, the acute oral LD50 of the test substance is estimated to be 560.3 mg/kg of body weight in female rats with an approximate 95% confidence interval of 950 mg/kg (upper) and 300 mg/kg (lower).

Applicant's summary and conclusion

Interpretation of results:

Toxicity Category IV

Remarks:

Migrated information LD50 = 560.3 mg/kg, which is between 300 and 2000 mg/kg bw. Criteria used for interpretation of results: EU

Conclusions:

The acute oral LD50 of Cetylpyridinium Chloride is estimated to be 560.3 mg/kg of body weight in female rats, with an approximate 95% confidence interval of 950 mg/kg (upper) and 300 mg/kg (lower)