Erich W. Bretthauer

The international toxicity equivalency factor (I-TEF) method of risk assessment for complex mixtures of dioxins and related compounds☆

Abstract The International Toxicity Equivalency Factor (I-TEF) method of risk assessment is an updated interim procedure for estimating the risks associated with exposures to complex mixtures of chlorinated dibenzo-p-dioxins and dibenzofurans (CDDs and CDFs). The I-TEF approach facilitates risk communication internationally by reducing large volumes of analytical data into a single number-International Toxicity Equivalents (I-TEQ). The I-TEF method has been officially adopted in Canada, the Netherlands, the Nordic countries, the United Kingdom, and the United States. As a result, the I-TEF method represents an improvement in an already useful risk assessment/regulatory tool.

The international toxicity equivalency factor (I‐TEF) method for estimating risks associated with exposures to complex mixtures of dioxins and related compounds∗

The International Toxicity Equivalency Factor (I‐TEF) method of risk assessment is a revised interim procedure for assessing the risks associated with exposures to complex mixtures of chlorinated dibenzo‐p‐dioxins and dibenzofurans (CDDs and CDFs). This updated scheme was developed by a working group of the North Atlantic Treaty Organizations Committee on the Challenges of Modern Society and has been officially adopted by the U.S. Environmental Protection Agency (EPA), Canada, Ontario Ministry of the Environment, the Nordic countries, the Netherlands, and the United Kingdom. Prior to the development of the I‐TEF method, at least ten slightly different schemes had been used throughout the world which complicated communication among scientists and regulatory agencies concerning the toxicological significance of complex mixtures of CDDs and CDFs. The I‐TEF approach facilitates risk communication internationally by reducing large volumes of analytical data into a single number‐International Toxicity Equivale...

Accomplishments of the NATO/CCMS pilot study on international information exchange on dioxins and related compounds∗

A project promoting the international exchange of information on chlorinated dibenzo‐p‐dioxins and dibenzofurans (CDDs and CDFs) was conducted under the auspices of the Committee on the Challenges of Modern Society (CCMS) of the North Atlantic Treaty Organization (NATO). Initiated in 1985, the Pilot Study on International Information Exchange on Dioxins and Related Compounds was a three‐year effort to improve the state of the art of dioxin research, regulation, and technology by encouraging collaboration among interested countries and organizations. Participating nations included Canada, Denmark, the Federal Republic of Germany, Italy, the Netherlands, Norway, the United Kingdom, and the United States. Numerous activities were accomplished to promote information exchange so that better informed decisions can be made concerning future research activities and resource allocations. Three major areas were addressed: Exposure and Hazard Assessment, Technology Assessment, and Management of Accidents. A total of...

Exposure and Hazard Assessment Working Group

The efforts of the Exposure and Hazard Assessment Working Group were focused on the exchange of information on a variety of topics including research projects, regulations/statutes, analytical laboratories, and methods of exposure/risk assessment involving CDDs and CDFs. It was evident to the leaders of the Working Group that several of the knowledge voids had to be addressed on a fundamental level before expanded efforts could be made. Several questions needed to be answered:

Technology Assessment Working Group

The Technology Assessment Working Group focused its attention on producing documents that reported the state of the art with respect to the formation of dioxins and related compounds from combustion and industrial sources, as well as methods of destruction and disposal.

Introduction and Background Information

The Pilot Study on International Information Exchange on Dioxins and Related Compounds was initiated to address issues associated with chlorinated dibenzo-p-dioxins (CDDs), dibenzofurans (CDFs), and related compounds. The 3-year project was initiated in 1985 under the auspices of the Committee on the Challenges of Modern Society (CCMS) of the North Atlantic Treaty Organization (NATO). Numerous activities were carried out to promote information exchange among the participating nations and to foster cooperative research efforts. The Pilot Study produced 15 CCMS documents, as well as numerous journal articles (Kutz and Bottimore, 1988; Bottimore et al., 1989), that describe the specific accomplishments of the project. The purpose of this volume is to describe, in detail, the participation, function, scope, and achievements of this project, which was completed in April 1988.

International information-exchange activities on dioxins

Abstract A project promoting the exchange of information on polychlorinated dibenzo- para -dioxins and related chemicals has been initiated on an international basis. The project is being conducted under the auspices of the Committee on the Challenges of Modern Society of the North Atlantic Treaty Organization with representation from the following nations: Canada, Denmark, Federal Republic of Germany, Italy, Netherlands, Norway, United Kingdom, and United States. Areas being studied include exposure and hazard assessment, technology assessment, and management of accidents.