Reproductive Hormones in the Environment

Low detections of reproductive hormones, at the part per trillion concentrations, are frequently measured in surface and subsurface waters. These exogenous hormones are a concern because they can bind strongly to hormone receptors in animals and induce an endocrine response or disruption. Human health concerns about acute environmental exposure to the exogenous hormones are low, but dangers from chronic exposures are unknown. Aquatic organisms, especially fish, are very sensitive to prolonged or intermittent exposures to low concentrations of exogenous reproductive hormones. Connections have been made to manure management practices at animal feeding operations (AFOs) and hormone detections in the environment. To better understand the connection between AFOs and hormones in the environment studies are needed to (i) clarify the role of AFOs with respect to environmental exposure to hormones, and (ii) identify the processes that control the fate and transport of hormones in the environment. An overview of hormone detections in surface and subsurface waters and at watershed scales will be present in context to AFOs. Also, the state of knowledge about processes that control hormone fate and transport in the environment will be presented.