and correspondence to the modeled natural ecosystems proved to be very high in
studies on the material cycle, energy flow, and interactions of microorganisms in the
microcosm system. The microcosm systems were not comparable with point locations, such as natural lakes, ponds, or rivers, but they were comparable with respect
to the function and structure of natural aquatic ecosystems. Based on this work, the
above approaches were suggested and applied to predict the effects of chemical
pollutants in a natural ecosystem. It was determined that the microcosm test was of
great importance when used as a model for biological assessments.
A microcosm using mice was employed as the model system to evaluate the
toxicity of chemicals and genetically modified organisms to ecosystems and humans.
Estimation from 106 examples of target materials (6 of surfactants, 3 of germicides,
14 of herbicides, 12 of pesticides, 2 of endocrine-disrupting chemicals, 1 of an
antibiotic, 1 of an algal bloom toxin, 6 of organic matter and solvents, 2 of nutrients,
15 of metals, 2 of radiation, 6 of microbial pesticides, 8 of genetically modified
bacteria, 13 involving biomanipulation, and 2 incorporating climate change;
Chap. 7) and 13 examples of the Whole Effluent Toxicity (WET) test (Chap. 9) is
described in this book. In the study reported here, research and development into the
environmental impact assessment of a chemical substance was conducted, paying
close attention to the microcosm, which is an aquatic model ecosystem consisting of
producers (phytoplankton), predators (zooplankton), and decomposers (bacteria).
Enactment per the international guidelines of the Organisation for Economic
Co-operation and Development (OECD) test of the general purpose microcosm
method in Japan was aimed for by setting the quantity of production/respiration
(P/R ratio), which can be used as a measure of change for the entire ecosystem that
can be incorporated into an assessment index. Traditionally, environmental impact
assessments of chemical substances have been performed using a single species, but
model ecosystems that imitate nature may be used to address the problems of
stability, reproducibility, and high costs; a standard test method has not been
established. However, a foundational manual concerning test operations has already
been established (Funds for the Overall Promotion of Environmental Research,
Ministry of the Environment, in FY2009-2011), and the ring test, which will be
performed in collaboration with several research institutions and developed for wide
use, is already planned to establish the OECD standard test method.
This book is composed of the following chapters:
1. Introduction
2. Standardization of the Microcosm N-System
3. Maintenance of the Microcosm N-System
4. Preparation of the Microcosm N-System
5. Procedure for Using the Microcosm N-System
6. Estimation Using the Microcosm N-System
7. Example Assessments of the Microcosm N-System
8. Coefficient of Assessment for the Microcosm System
9. Application to the Whole Effluent Toxicity Test
10. A Scaled-Up Model Ecosystem Verification of the Microcosm N-System
Preface
vii
studies on the material cycle, energy flow, and interactions of microorganisms in the
microcosm system. The microcosm systems were not comparable with point locations, such as natural lakes, ponds, or rivers, but they were comparable with respect
to the function and structure of natural aquatic ecosystems. Based on this work, the
above approaches were suggested and applied to predict the effects of chemical
pollutants in a natural ecosystem. It was determined that the microcosm test was of
great importance when used as a model for biological assessments.
A microcosm using mice was employed as the model system to evaluate the
toxicity of chemicals and genetically modified organisms to ecosystems and humans.
Estimation from 106 examples of target materials (6 of surfactants, 3 of germicides,
14 of herbicides, 12 of pesticides, 2 of endocrine-disrupting chemicals, 1 of an
antibiotic, 1 of an algal bloom toxin, 6 of organic matter and solvents, 2 of nutrients,
15 of metals, 2 of radiation, 6 of microbial pesticides, 8 of genetically modified
bacteria, 13 involving biomanipulation, and 2 incorporating climate change;
Chap. 7) and 13 examples of the Whole Effluent Toxicity (WET) test (Chap. 9) is
described in this book. In the study reported here, research and development into the
environmental impact assessment of a chemical substance was conducted, paying
close attention to the microcosm, which is an aquatic model ecosystem consisting of
producers (phytoplankton), predators (zooplankton), and decomposers (bacteria).
Enactment per the international guidelines of the Organisation for Economic
Co-operation and Development (OECD) test of the general purpose microcosm
method in Japan was aimed for by setting the quantity of production/respiration
(P/R ratio), which can be used as a measure of change for the entire ecosystem that
can be incorporated into an assessment index. Traditionally, environmental impact
assessments of chemical substances have been performed using a single species, but
model ecosystems that imitate nature may be used to address the problems of
stability, reproducibility, and high costs; a standard test method has not been
established. However, a foundational manual concerning test operations has already
been established (Funds for the Overall Promotion of Environmental Research,
Ministry of the Environment, in FY2009-2011), and the ring test, which will be
performed in collaboration with several research institutions and developed for wide
use, is already planned to establish the OECD standard test method.
This book is composed of the following chapters:
1. Introduction
2. Standardization of the Microcosm N-System
3. Maintenance of the Microcosm N-System
4. Preparation of the Microcosm N-System
5. Procedure for Using the Microcosm N-System
6. Estimation Using the Microcosm N-System
7. Example Assessments of the Microcosm N-System
8. Coefficient of Assessment for the Microcosm System
9. Application to the Whole Effluent Toxicity Test
10. A Scaled-Up Model Ecosystem Verification of the Microcosm N-System
Preface
vii