Estuaries and Endocrine Disruptors

Contributing to the degradation of estuaries are the multitude of synthetic organic compounds used in a variety of industrial, agricultural, household and pharmaceutical products. These compounds are often referred to as persistent organic contaminants (POPs). They are difficult or impossible to remove by conventional water and wastewater treatment methods, and they easily find their way into estuarine systems, often at very low concentrations.  POPs that exist at very low concentrations are also referred to as organic micropollutants: the majority of endocrine disrupting chemicals (EDC’s) in estuaries are organic micropollutants.

It is known that EDCs can inhibit the reproductive processes, development, sexual maturation, gender distributions, behavior and immune function in estuarine aquatic organisms by disrupting endocrine biochemistry. However, the degree to which EDCs threaten estuaries is uncertain. There are many reasons for this: the vast number of known or suspected EDCs, the pace of development and use of new EDCs, their low concentrations in water and sediment, the challenges related to EDC sampling and analysis, the environmental complexities inherent in estuarine systems, and our limited understanding of the physical, chemical and biochemical behavior and fate of EDCs in estuarine systems. What is clear today is that many EDCs are resistant to natural degradation, can bioaccumulate in estuarine organisms, can have toxic effects and disrupt normal hormonal behavior in some estuarine organisms. Moreover, once in the estuarine environment, EDCs can biochemically transform in ways that may increase their danger to estuarine organisms. For these reasons and others, EDCs have the potential to dramatically affect estuarine organisms with far-reaching, yet uncertain ecological consequences.