Endocrine Disruption in Fish

The last half-century has shown a dramatic increase in the standard of living of millions of people in Europe, North America and many parts of the Third World. This has, in many ways been brought about by scientific and technical developments which were initiated in the 1940s and 1950s. Promises were then made that nuclear energy would provide electricity so cheap that it would not need metering, pesticides would end malnutrition throughout the world and plastics and other synthetic chemicals would revolutionise our manufacturing industry and our way of life. Whilst some of these promises have been fulfilled, the problems of long-term health risks to humans and wildlife arising from the use, production and disposal of these products were either unknown or deliberately understated. Nuclear power is rendered economically unviable when the real cost of decommissioning and storage of waste for several millenia is included, and the effects on health of both humans and wildlife of early pesteradication programmes with organochlorine pesticides were well documented in Rachel Carson's "Silent Spring". Evidence of the effects of aerosols and refrigerants on depletion of the ozone layer has led to restriction on the use of CFCs, and there is now increasing evidence of climate change resulting from our profligate use of fossil fuels.

Table of Contents:
1. Introduction.- 1.1 Environmental Pollution.- 1.2 Endocrine Disruption.- 1.3 The Need for Biomonitors.- 1.4 Why Use Fish as Biomonitors?.- 2. Sources of Aquatic Pollution.- 2.1 The Origin of Pollutants.- 2.2 Types of Pollutant.- 3. Bioconcentration in Fish Tissue.- 3.1 Introduction.- 3.2 Tissue Distribution.- 3.3 Factors Affecting Uptake of Pollutants By Fish.- 3.4 Uptake of Pollutants into Eggs and Larvae.- 3.5 Tissue Concentrations as a Bioindicator of Aquatic Pollution.- 4. Introduction to Fish Reproduction.- 4.1 Introduction.- 4.2 Seasonal Cues for Reproduction.- 4.3 The Teleost Endocrine System.- 4.4 Seasonal Changes in Hormones and Gonads.- 4.5 Courtship Behaviour and Spawning.- 4.6 Reproductive Strategies.- 4.7 Fecundity and Fertility.- 4.8 Sex Determination and Reversal.- 4.9 Impact of Pollutants.- 4.10 Mechanisms of Action.- 4.11 Experimental Approaches.- 5. Disruption of Hypothalamic and Pituitary Function.- 5.1 The Hypothalamic-Pituitary System in Fish.- 5.2 Effects of Pollutants on the Hypothalamus.- 5.3 Effects of Pollutants on the Pituitary.- 5.4 Conclusions.- 6. Disruption of Male Reproductive Function.- 6.1 Introduction.- 6.2 Effects on Testicular Morphology.- 6.3 Effects on Testicular Hormone Production.- 6.4 Effects on Sperm Viability.- 6.5 Other Effects on the Male.- 6.6 Conclusions.- 7. Disruption of Female Reproductive Function.- 7.1 Introduction.- 7.2 Effects on Ovarian Morphology.- 7.3 Effects on Steroidogenesis.- 7.4 Other Biochemical Indicators of Ovarian Activity.- 7.5 Effects on Ovulation and Spawning.- 7.6 Effects on Egg Numbers and Viability.- 7.7 Effects of Parental Exposure on Viability of Offspring.- 7.8 Conclusions.- 8. Disruption in Eggs, Embryos, Larvae and Juvenile Fish.- 8.1 Introduction.- 8.2 Exposure of Eggs and Embryos.- 8.3 Exposure of Larval and Juvenile Fish.- 8.4 Conclusions.- 9. Disruption of Liver Function.- 9.1 Introduction.- 9.2 Morphological Effects.- 9.3 Effects on Hepatic Enzymes and Proteins.- 9.4 Vitellogenesis.- 9.5 Conclusions.- 10. Disruption of Thyroid and Interrenal Function.- 10.1 The Endocrinology of the Thyroid and Interrenal Glands.- 10.2 Effects on the Thyroid.- 10.3 Growth.- 10.4 The Stress Response.- 10.5 Osmoregulation.- 10.6 The Immune System and Disease.- 10.7 Conclusions.- 11. The Fish-Wildlife-Human Connection.- 11.1 Introduction.- 11.2 Health Hazards From Dietary Fish.- 11.3 Hazards to Human Populations.- 11.4 Testing for Endocrine Modulators.- 11.5 Conclusion.- References.- Species Key.