statistical difference between the control system and λ-Cyhalothrin addition system
at any concentration (Sugiura 1992).
7.5 Endocrine-Disrupting Chemicals
Endocrine systems are found in all vertebrate and most invertebrate species. The
endocrine system is made up of glands, which secrete hormones to body fluids, and
receptor cells, which detect and react to the hormones. The hormones act as chemical
messengers. Hormones bind to cells that contain matching receptors in or on their
surfaces, much like a key would fit into a lock. Disruption of the endocrine system
can occur in various ways. Some chemicals mimic a natural hormone, fooling the
body into overresponding to the stimulus or responding at inappropriate times. Other
endocrine disruptors block the receptor site on a cell. Still others directly stimulate or
inhibit the endocrine system and cause overproduction or underproduction of hormones. The substances that exhibit these effects are known as endocrine-disrupting
chemicals (EDCs) or hormone-disrupting chemicals (HDCs). The most conspicuous
EDCs are those that affect reproduction. Endocrine-disrupting chemicals have been
demonstrated to markedly affect animal populations in coastal environments.
Hormone-disrupting chemicals, or environmental endocrine-disrupters, as they
are also known, are the materials that are doubted to disturb the action of hormones
in a living body. When taken into a living body, hormone action, such as the
synthesis, storage, and secretion of hormones, is obstructed. For example, EDCs
can inhibit generative functions, possibly causing malignant tumors.
7.5.1 Nonylphenol
The statistically significant difference was taken as the NOEC of 0.1 mg/L of
Nonylphenol, and there was a statistically significant difference observed between
the experimental microcosm and the control system with the addition of 1 mg/L.
Therefore, it was determined there was influence on the ecosystem with the addition
of 1 mg/L of Nonylphenol. The amounts of production (P) and respiration (R) at a
Nonylphenol concentration of 0.2 mg/L were nearly the same as those of the control
system, but there was a slight difference observed between concentrations of 0.1 mg/
L and 0.2 mg/L (Fig. 7.21).
104
K. Murakami et al.
at any concentration (Sugiura 1992).
7.5 Endocrine-Disrupting Chemicals
Endocrine systems are found in all vertebrate and most invertebrate species. The
endocrine system is made up of glands, which secrete hormones to body fluids, and
receptor cells, which detect and react to the hormones. The hormones act as chemical
messengers. Hormones bind to cells that contain matching receptors in or on their
surfaces, much like a key would fit into a lock. Disruption of the endocrine system
can occur in various ways. Some chemicals mimic a natural hormone, fooling the
body into overresponding to the stimulus or responding at inappropriate times. Other
endocrine disruptors block the receptor site on a cell. Still others directly stimulate or
inhibit the endocrine system and cause overproduction or underproduction of hormones. The substances that exhibit these effects are known as endocrine-disrupting
chemicals (EDCs) or hormone-disrupting chemicals (HDCs). The most conspicuous
EDCs are those that affect reproduction. Endocrine-disrupting chemicals have been
demonstrated to markedly affect animal populations in coastal environments.
Hormone-disrupting chemicals, or environmental endocrine-disrupters, as they
are also known, are the materials that are doubted to disturb the action of hormones
in a living body. When taken into a living body, hormone action, such as the
synthesis, storage, and secretion of hormones, is obstructed. For example, EDCs
can inhibit generative functions, possibly causing malignant tumors.
7.5.1 Nonylphenol
The statistically significant difference was taken as the NOEC of 0.1 mg/L of
Nonylphenol, and there was a statistically significant difference observed between
the experimental microcosm and the control system with the addition of 1 mg/L.
Therefore, it was determined there was influence on the ecosystem with the addition
of 1 mg/L of Nonylphenol. The amounts of production (P) and respiration (R) at a
Nonylphenol concentration of 0.2 mg/L were nearly the same as those of the control
system, but there was a slight difference observed between concentrations of 0.1 mg/
L and 0.2 mg/L (Fig. 7.21).
104
K. Murakami et al.