reaching approximately 5000 individuals from 70 countries in 2004. SETAC’s
official journal, Environmental Toxicology and Chemistry, was launched in 1982
and has since become widely recognized as one of the most influential
publications in the field of environmental science. The society holds an annual
meeting in November in different cities in the U.S., where 2000 to 3000
individuals participate in presentation or discussion of new findings.
Clearly, a large number of scientists in the U.S. and various other countries
are pursuing careers directly or indirectly related to environmental toxicology.
The importance of their contributions to the enhancement of environmental
quality and human welfare has become increasingly recognized.
1.5 TOXICITY TESTING À A BRIEF REVIEW
1.5.1 INTRODUCTION
This section presents a brief introduction to toxicity testing. Several terms used
in environmental toxicology are also included. Toxicity is the property or
properties of a material that produces a harmful effect upon a biological
system, and the agent that produces such a biological effect is termed as a
toxicant. The majority of the toxic chemicals discussed in this volume are of
man-made or anthropogenic origin. It is true that some of the materials that
are produced naturally by biological systems are extremely potent, e.g., the
fungal aflatoxins and venom; however, these materials are usually produced
only in small amounts. In contrast, anthropogenically produced materials can
amount to millions of kilograms per year.
4
Toxicants enter the environment by a variety of routes from many different
sources. Toxicants introduced into the environment may come from two basic
sources: point sources and nonpoint sources. Discharges from point sources
include sewage discharges, waste streams from industrial sources, hazardouswaste disposal sites, and accidental spills. Point discharges are generally easy to
6
Environmental Toxicology
[16:55 26/8/04 P:/CRC PRESS/4365 MING-HO.751 (1670)/4365-001.3d]
Ref: 4365 MING-HO YU Chap-001 Page: 6 1-12
FIGURE 1.3 Interrelationships between environmental toxicology and various scientific disciplines.
official journal, Environmental Toxicology and Chemistry, was launched in 1982
and has since become widely recognized as one of the most influential
publications in the field of environmental science. The society holds an annual
meeting in November in different cities in the U.S., where 2000 to 3000
individuals participate in presentation or discussion of new findings.
Clearly, a large number of scientists in the U.S. and various other countries
are pursuing careers directly or indirectly related to environmental toxicology.
The importance of their contributions to the enhancement of environmental
quality and human welfare has become increasingly recognized.
1.5 TOXICITY TESTING À A BRIEF REVIEW
1.5.1 INTRODUCTION
This section presents a brief introduction to toxicity testing. Several terms used
in environmental toxicology are also included. Toxicity is the property or
properties of a material that produces a harmful effect upon a biological
system, and the agent that produces such a biological effect is termed as a
toxicant. The majority of the toxic chemicals discussed in this volume are of
man-made or anthropogenic origin. It is true that some of the materials that
are produced naturally by biological systems are extremely potent, e.g., the
fungal aflatoxins and venom; however, these materials are usually produced
only in small amounts. In contrast, anthropogenically produced materials can
amount to millions of kilograms per year.
4
Toxicants enter the environment by a variety of routes from many different
sources. Toxicants introduced into the environment may come from two basic
sources: point sources and nonpoint sources. Discharges from point sources
include sewage discharges, waste streams from industrial sources, hazardouswaste disposal sites, and accidental spills. Point discharges are generally easy to
6
Environmental Toxicology
[16:55 26/8/04 P:/CRC PRESS/4365 MING-HO.751 (1670)/4365-001.3d]
Ref: 4365 MING-HO YU Chap-001 Page: 6 1-12
FIGURE 1.3 Interrelationships between environmental toxicology and various scientific disciplines.