Humans take and rely on medications to improve our quality of life. However, these drugs have a dark side that is easily overlooked.
When we take a medication, our bodies do not always use the entire dose. Consequently, we excrete small portions of that drug or a biologically active metabolite in our waste. These drugs are then flushed away, where they end up in wastewater treatment facilities. Unfortunately many of these facilities are not typically designed to remove these active compounds, which are eventually released into our streams and rivers. Ageing sewage infrastructure, septic tanks and even recycled municipal wastewater also contribute to this problem.
Almost two decades ago, the first landmark study on pharmaceuticals in our freshwater environment revealed that streams and rivers across the United States were awash with a cocktail of many drugs (https://goo.gl/PSVi5o). Since then, many studies have detected the presence of human pharmaceuticals in our waterways, including recently in Antarctica (https://goo.gl/KxGvXd).
Pharmaceuticals are ubiquitous in the freshwater environments, so it’s not surprising that they pose a serious threat to “non-target” organisms. They have caused the feminisation of male fish...