Background to the Publication of Toxicity Testing Reports for Environmental Chemicals and the Framework of the Reports

Published by Chemicals Investigation Promoting Council, Japan

Supervised by Office of Chemicals Safety
Evaluation and Licensing Bureau
Pharmaceutical and Food Safety Bureau

Ministry of Health, Labour and Welfare, Japan

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I. Publishing Background

Toxicity tests play important roles in providing basic reference data for safety programmes of the government or industries.

Japan has been studying chemical toxicity under the initiative of the National Institute of Health Sciences and has also been performing safety tests of existing chemicals with high production volume (HPV) in cooperation with the U.S., the EC, and other OECD member countries as one of the OECD Chemicals programme Group members since 1991. These data being generated are very important to ensure chemical safety. Furthermore common utilization of the data among the member countries facilitates global enforcement of safety programmes.

Toxicity studies conducted for individual environmental chemicals include a single dose toxicity test, a 28-day repeat dose toxicity test, a reproductive/development toxicity test and mutagenicity tests. Each test has various practical and academic contents such as animal species, dose, test method and types of toxicity appearance. The results are intended for publication as academic report documents.

The Chemical Investigation Promoting Council in Japan has been discussing technical issues for toxicity studies from the academic standpoint. The Council had therefore decided to publish Toxicity Testing Reports of Environmental Chemicals in cooperation with scientists from National Institute of Heath Sciences and other institutes.

Chemical pollution is one of the most controversial issues in the world. This report is designed to provide useful for basic information for approaches to protection from chemical hazard, giving a thorough understanding of the tests, and the underlying concepts.

II. Framework of the report

1. Chemicals listed in this report

Japan has been proceeding with safety tests of existing chemicals in Japan on its own initiative, in addition to cooperating in the HPV chemicals testing programme of the OECD Chemical programme Group which was started in 1991.

This book includes results of toxicity screening tests for both Japan's existing chemicals safety programme and the OECD HPV chemicals programme.

2. Review of safety programmes for environmental chemicals

The outline and current status of safety programmes in Japan are reviewed prior to the test reports for each chemical. The review covers general explanations including the position and roles of toxicity tests in safety programmes as well as considering points for the future.

3. Contents of the reports

For each chemical, results are compiled from several studies, including, in most cases, a single dose toxicity test, a 28-day repeat dose toxicity test, a reproductive/development toxicity test and mutagenicity tests. Each report consists of the nomenclature of the chemical, abstracts and summarized data from the studies in English, and toxicity test results in order.

(1) Nomenclature of chemicals

IUPAC, CAS and common names are all in use for naming chemicals. In this report, CAS names are applied for most OECD testing chemicals, and IUPAC names for most existing chemicals in Japan. And common names are listed on the 1st page for each chemical where applicable. All of the chemicals names are listed in the List of Chemical Substances Tested in the following table.

(2) ABSTRACT and SUMMARIZED DATA FROM THE STUDIES in English

The ABSTRACTs are written covering all toxicity tests conducted for the chemical in question. The SUMMARIZED DATA FROM THE STUDIES includes conditions and results of each test referring to OECD Form 1.

(3) Toxicity test reports

Toxicity test data is compiled in order as follows;

a. Single dose oral toxicity test

b. 28-day repeat dose oral toxicity test

c. Preliminary reproduction toxicity screening test

d. Combined repeat dose and reproductive/developmental toxicity screening test

e. Reverse mutation test

f. Chromosomal aberration test

III. Test methods

1. All the toxicity tests reported were performed in accordance with the test methods in which new chemicals should be tested for submission to the country agencies under the Law concerning Examination and Regulation of Manufacture, etc. of Chemical Substances, and each guideline of the OECD chemicals programmes.

2. In the OECD safety testing programme, the toxicity tests actually conducted for the chemical are decided on the basis of available toxicity information. Regarding reproductive/developmental studies, a preliminary reproductive toxicity test is applied to chemicals for which repeat dose test data already exist. Combined repeat dose and reproductive/developmental toxicity screening test (ReproTox) is applied to chemicals for which repeat dose test data do not exist.

The ReproTox was designed for the OECD safety testing programme several years ago.

Scientists in OECD Test Guideline programmes have subsequently been discussing and revising the ReproTox used in this report. The test results reported in this book were the data from the tests conducted in accordance with the currently proposed guideline, which is shown in the Appendix.

In the near future, the OECD official guideline is to be authorized.

3. All the tests reported were performed in accordance with the chemicals GLP under the Law concerning Examination and Regulation of Manufacture, etc. of Chemical Substances and also meet the requirements of the OECD GLP.