ASTM E1619-11(2016)

Standard Test Method for Chronic Oral Toxicity Study in Rats

SIGNIFICANCE AND USE
5.1 This test method should generate data to identify the majority of chronic effects and shall serve to define long-term dose response relationships. In addition the test should allow for the detection of general toxic effects including neurological, physiological, biochemical, and hematological effects and exposure-related morphological (pathology) effects.  
5.2 This test method should provide information on target organs, the possibilities of accumulation, and may be used for establishing safety criteria for human exposure. It provides information on potential health hazards likely to arise from repeated exposure over a long period of time.
SCOPE
1.1 This test method covers a long-term study to determine the effects of a substance in a mammalian species such as the rat following prolonged and repeated oral exposure. Under the conditions of the chronic toxicity test, effects that require a long latency period or that are cumulative should become manifest.  
1.2 This test method assumes that the user is knowledgeable in mammalian toxicology and related pertinent areas, and relies heavily on the judgment of the evaluator.  
1.3 The values stated in SI units are to be regarded as the standard. The inch-pound units given in parentheses are for information only.  
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. For specific hazard statements, see Section 6.

General Information

• Status: Published
• Publication Date: 31-Jan-2016
• ICS: 11.100.30 - Analysis of blood and urine
• Technical Committee: E50 - Environmental Assessment, Risk Management and Corrective Action
• Drafting Committee: E50.47 - Biological Effects and Environmental Fate

Relations

• Replaces: ASTM E1619-11 - Standard Test Method for Chronic Oral Toxicity Study in Rats
• Effective Date: 01-Feb-2016
• Refers: ASTM E609-16 - Standard Terminology Relating to Pesticides
• Effective Date: 15-Sep-2016
• Refers: ASTM E609-15a - Standard Terminology Relating to Pesticides
• Effective Date: 01-May-2015
• Refers: ASTM E609-15 - Standard Terminology Relating to Pesticides
• Effective Date: 01-Jan-2015
• Refers: ASTM E609-10 - Standard Terminology Relating to Pesticides
• Effective Date: 01-Mar-2010
• Refers: ASTM E943-08 - Standard Terminology Relating to Biological Effects and Environmental Fate
• Effective Date: 01-Mar-2008
• Refers: ASTM E609-05 - Standard Terminology Relating to Pesticides
• Effective Date: 01-Apr-2005
• Refers: ASTM E609-04 - Standard Terminology Relating to Pesticides
• Effective Date: 01-Nov-2004
• Refers: ASTM E609-03a - Standard Terminology Relating to Pesticides
• Effective Date: 01-Oct-2003
• Refers: ASTM E609-02a - Standard Terminology Relating to Pesticides
• Effective Date: 10-Oct-2002
• Refers: ASTM E609-03 - Standard Terminology Relating to Pesticides
• Effective Date: 10-Oct-2002
• Refers: ASTM E609-02 - Standard Terminology Relating to Pesticides
• Effective Date: 10-Apr-2001
• Refers: ASTM E609-00 - Standard Terminology Relating to Pesticides
• Effective Date: 10-Apr-2001
• Refers: ASTM E609-81(1997)e1 - Standard Terminology Relating to Pesticides
• Effective Date: 10-Apr-2001

Overview

ASTM E1619-11(2016) - Standard Test Method for Chronic Oral Toxicity Study in Rats - is an internationally recognized protocol developed by ASTM for identifying chronic effects of substances in mammals, specifically using rats. This standard provides a comprehensive framework for conducting long-term toxicity studies, focusing on dose-response relationships, the detection of general and organ-specific toxic effects, and the accumulation of test substances. The results from this test method are essential for establishing safety criteria and determining potential risks related to prolonged human exposure.

Key Topics

• Chronic Toxicity Evaluation
  The method investigates adverse effects from prolonged and repeated oral exposure in rats, suitable for observing cumulative and long-latency toxic responses.

• Test Design and Animal Use

  • Employs at least forty rats per dosage group (20 males, 20 females), with four dose levels plus control.
  • Test substance administration spans one year, using diet, water, or direct dosing (gavage/capsule).
  • Requires statistical comparison of control and treated groups on parameters such as body/organ weights, blood and urine chemistry, and observed symptoms.

• Detection of Toxic Effects
  The protocol allows for:

  • Identification of target organs.
  • Detection of neurological, physiological, biochemical, and hematological effects.
  • Morphological assessments via histopathology of vital organs and tissues.

• Data for Long-Term Safety Assessment
  The method generates reliable data that supports regulatory submissions and risk assessment for chemicals, pharmaceuticals, pesticides, and other materials.

• Laboratory and Ethical Requirements

  • Recommends adherence to Good Laboratory Practice (GLP) and ethical guidelines for animal care and use.
  • Requires acclimation and consistent animal age and strain to reduce variability.

Applications

ASTM E1619-11(2016) is broadly applicable for:

• Chemical and Pharmaceutical Safety Assessment
  Utilized by manufacturers, research labs, and regulators to generate safety data required for registration and risk evaluation.

• Environmental and Occupational Health
  Supports the determination of safe exposure limits for workers and the public through comprehensive chronic oral toxicity data.

• Pesticide Registration
  Required for the regulatory assessment of agricultural chemicals, ensuring long-term human safety.

• Toxicology Research and Product Development
  Informs product safety evaluations and guides modifications during the development of new substances or formulations.

Related Standards

• ASTM E609 - Terminology Relating to Pesticides
• ASTM E943 - Terminology Relating to Biological Effects and Environmental Fate
• EPA GLP Regulations (Title 40 CFR Parts 160, 792, 798) - Standards for nonclinical laboratory studies and health effects testing
• FDA GLP Regulations (Title 21 CFR Part 58)
• World Trade Organization TBT Principles - Supporting international harmonization of test methods

Practical Value

Implementing ASTM E1619-11(2016) ensures rigor, reproducibility, and international acceptance of chronic oral toxicity data. Key benefits include:

• Generating robust safety data to inform risk assessments.
• Supporting regulatory submissions for chemicals and pharmaceuticals.
• Facilitating detection of both expected and unexpected chronic toxicological effects.
• Contributing to the continual improvement of public health protections.
• Providing a transparent methodology aligned with globally recognized standards.

Keywords: chronic oral toxicity, rats, long-term toxicity study, dose response, test method, safety assessment, histopathology, risk evaluation, regulatory compliance, GLP, chemical safety, pharmaceutical toxicology.

Standards Content (Sample)

This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
Designation: E1619 − 11 (Reapproved 2016)
Standard Test Method for
Chronic Oral Toxicity Study in Rats
This standard is issued under the fixed designation E1619; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope Administration, Part 58, Good Laboratory Practice for
Nonclinical Studies
1.1 This test method covers a long-term study to determine
Title 40, CFR, Toxic Substance ControlAct, Part 792, Good
the effects of a substance in a mammalian species such as the
Laboratory Practice Standards
rat following prolonged and repeated oral exposure. Under the
Title 40, CFR, Environmental Protection Agency, Part 798,
conditions of the chronic toxicity test, effects that require a
Health Effects Testing Guidelines, Subpart D, Chronic
long latency period or that are cumulative should become
Exposure, Chronic Toxicity
manifest.
1.2 This test method assumes that the user is knowledgeable
3. Terminology
inmammaliantoxicologyandrelatedpertinentareas,andrelies
3.1 Definitions—See Terminology E609 and Terminology
heavily on the judgment of the evaluator.
E943.
1.3 The values stated in SI units are to be regarded as the
3.2 Definitions of Terms Specific to This Standard:
standard. The inch-pound units given in parentheses are for
3.2.1 chronic toxicity, n—the adverse effects occurring as a
information only.
result of the daily exposure of mammalian species to a test
1.4 This standard does not purport to address all of the
substance by diet, water, capsule, or gavage for a one-year
safety concerns, if any, associated with its use. It is the
period.
responsibility of the user of this standard to establish appro-
3.2.2 concentration, n—the weight of test substance per unit
priate safety and health practices and determine the applica-
weight of the diet (expressed as milligrams per kilogram of
bility of regulatory limitations prior to use. For specific hazard
diet). The weight of test substance per volume of H O
statements, see Section 6.
(expressed as milligrams per millilitre of water), or at a
constant rate in the diet (expressed as parts per million).
2. Referenced Documents
2 3.2.3 feed effıciency, n—this value is a measure of the
2.1 ASTM Standards:
efficiency with which the animals convert food to body weight.
E609 Terminology Relating to Pesticides
The calculation is the total body weight gain per total food
E943 Terminology Relating to Biological Effects and Envi-
consumed.
ronmental Fate
3 3.2.4 gavage, n—forced feeding, as by tube that is passed
2.2 Federal Standards:
down the throat to the stomach.
Title 40, Code of Federal Regulations (CFR), Environmental
3.2.5 test substance, n—pesticide or other material
Protection Agency, Subchapter E, Pesticide Programs:
Part 160, Good Laboratory Practice Standards (element, chemical compound, formulation, known mixture)
administered orally for the purpose of determining chronic
Title21, CodeofFederalRegulations(CFR).FoodandDrug
toxicity.
4. Summary of Test Method
This test method is under the jurisdiction of ASTM Committee E50 on
Environmental Assessment, Risk Management and Corrective Action and is the
4.1 One mammalian species, a rodent, is required; the rat is
direct responsibility of Subcommittee E50.47 on Biological Effects and Environ-
the preferred rodent. Forty rats (twenty females and twenty
mental Fate.
Current edition approved Feb. 1, 2016. Published May 2016. Originally
males) are used at each of the five dose levels (control-, low-,
approved in 1994. Last previous edition approved in 2011 as E1619 – 11. DOI:
two intermediate levels-, and high-dosage groups). If it is
10.1520/E1619-11R16.
determined that an interim sacrifice is necessary, the number
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website.
3 4
Available from U.S. Government Publishing Office, 732 N. Capitol St., NW, Benitz, K. F., “Measurement of Chronic Toxicity,” Methods of Toxicology, ed.
Washington DC 20401-0001, http://www.gpo.gov. G. E. Paget, Blackwell Scientific Publications, Oxford, England, 1970, pp. 32-131.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
E1619 − 11 (2016)
should be increased by the number of animals scheduled to be lines suggested by the Institute of Laboratory Resources or
sacrificed during the course of the study (see CFR, Title 40, facilities that have been approved by such organizations as the
Part 798). American Association for Accreditation of Laboratory Animal
Care (AAALAC).
4.2 The high-dose level in rats should elicit some signs of
toxicity without causing excessive lethality. The lowest dosage 7.2 Environment—House test and control animals in cages
level should be one that does not induce any evidence of designed to hold laboratory animals. Provide for appropriate
toxicity. This level should be higher (if possible) than that water and food consumption. Maintain all animals in a
expected for human exposure. The intermediate-dosage level temperature-, humidity-, and light-controlled room. The con-
should produce a minimal observable effect. Where ditions should be 18 to 26°C (64.4 to 78.8°F) for temperature,
appropriate, a vehicle control (the volume of which corre- 40 to 70 % for humidity, and a 12-h light, 12-h dark lighting
sponds to the volume of vehicle at the highest exposure level) cycle.
should be used.The selection of test substance dosages may be
estimated from a preliminary 14-day range finding study. 8. Test Animals
4.3 Daily observations of all individual animals for signs of
8.1 Perform the test with one mammalian species; the rat is
toxicity and mortality are recorded. the preferred rodent species. If another mammalian species is
used, justification or reasoning for the selection must be
4.4 Afteroneyear,priortonecropsy,urine,hematology,and
recorded.
blood samples are collected for analysis and then test animals
are sacrificed.
8.2 Obtain rats three weeks post-weaning. The Sprague-
Dawley (COBS/CD) rat is an example of a strain frequently
4.5 Data collected from treatment and control groups are
used. The females should be nulliparious and nonpregnant.
compared statistically to detect changes in food or water
Acclimate the animals for a period of no less than seven days.
consumption, or both, body weights, organ-to-body weight,
Dosing of rats should begin ideally before six weeks old, but
and organ-to-brain weight ratios, hematology, and clinical
no later than eight weeks of age.
blood and urine values. Histopathological examinations are
also performed on selected tissues. 8.3 All animals for a given test must come from one source
and strain and be approximately the same age to minimize
5. Significance and Use
variability. Test animals may be obtained from commercial
sourcesorrearedinlaboratorycolonies,buttheymustnothave
5.1 This test method should generate data to identify the
been used in a previous test. Animals should be healthy and
majority of chronic effects and shall serve to define long-term
disease free and those that are deformed, injured, emaciated or
dose response relationships. In addition the test should allow
phenotypically different from normal animals must not be used
for the detection of general toxic effects including
as test subjects.
neurological, physiological, biochemical, and hematological
effectsandexposure-relatedmorphological(pathology)effects.
9. Diets
5.2 This test method should provide information on target
9.1 The preferred administration of test substance is incor-
organs, the possibilities of accumulation, and may be used for
porated into a diet. However, the test substance may be
establishing safety criteria for human exposure. It provides
administered dissolved in drinking water or a solvent, or given
information on potential health hazards likely to arise from
by gavage or capsule for a period of at least twelve months.
repeated exposure over a long period of time.
The choice of route of administration depends upon the
physical and chemical characteristics of the test substance.
6. Hazards
9.1.1 If the test substance is administered by gavage, a five-
6.1 Minimize contact with all test substances and solutions
day/week dosing regimen is acceptable.
with appropriate protective clothing, gloves, eye protection,
9.1.2 When necessary, dissolve or suspend the test sub-
etc. The use of fume hoods and increased ventilation in test
stance in a suitable solvent. If a vehicle or diluent is needed, it
rooms is necessary when handling volatile substances. Infor-
should not elicit toxic effects itself nor substantially alter the
mation concerning acute mammalian toxicity and special
chemical or toxicological properties of the test substance.
handling procedures should be known before this test method
9.2 Formulate diets in accordance with the nutrient require-
is used.
ments of the test species. Any unmedicated commercial diet
6.2 Dispose excess test substance, solutions, diets, excreta,
thatmeetstheminimumnutritionalstandardsofthetestspecies
and treated animals with consideration for health and environ-
is acceptable.
mental safety, and in accordance with all federal, state, and
local regulations.
10. Range-Finding Study
7. Facilities 10.1 Previous data or a range-finding study should be
used/conducted to assist in the selection of the appropriate
7.1 No precise physical requirements concerning facilities
doses for the chronic study.
are set forth. However, the animal facility shall meet the
established standard(s) that may be required by law or regula- 10.2 Use groups of six male and six female rats between six
tions. It is desirable that the animal facilities meet the guide- and eight weeks of age. Randomize, number, and place all
E1619 − 11 (2016)
animals in appropriate cages for a five-day acclimation period.
K = dosage of substance that is desired and is expressed as
During this period, all rats will receive rodent diet minus the
grams of test substance/kilogram of body weight/day,
test substance. Dietary levels of the test substance to be
G = amount of food consumed/day over a one-week period
administered may approximate the acute oral LD dosages
and is expressed as grams of food consumed per
and fractions thereof (such as 1X, 0.5X, 0.25X, 0.125X,
kilogram of body weight/day.
0.0625X,0.03125XoftheLD ).Oneadditionalgroupofeach
Record food consumption (and water if necessary) through-
sex will serve as a solvent or untreated control.
out the study.
10.3 It is strongly recommended that a dietary group be
11.5.2 An alternative to this test method would be to
removed from testing for humane purposes when food con-
determine the concentration of test substance in the feed prior
sumption is markedly reduced. If consumption as compared to
to study initiation and then have it remain constant throughout
controls or acclimation period values, or both, is reduced by
the study.
more than 90 %, continued exposure will result in mortality of
11.6 Observations—Make observations of each
...