Imagine you are an enthusiastic gardener and cherish a perfect lawn. Instead of picking the weeds by hand you use an herbicide that kills all the weeds except the grass. The result is that you will have added a considerable amount of chemicals to the soil, some of which are nasty, persistent and will stay around for a long time. The rain will transport these chemicals via sewage systems to rivers, and ultimately these chemicals will end up somewhere, in lakes or the sea. There they will enter the food chain, and be part of your next fish dinner.
Trying to keep track of how pollutants spread through the soil, ground water, and rivers, and how they are transformed is the aim of FATE (Fate and impacts of pollutants in terrestrial and aquatic ecosystems), a research action by the European Commission's in-house science service, the Joint Research Centre (JRC). "We work with different groups dealing with environmental policies and colleagues in the European Commission, providing the scientific underpinning for the actions to be taken2" says Giovanni Bidoglio, unit head of "water resources" in the JRC.
A wide range of pollutants affect the terrestrial and aquatic ecosystem. They originate from industry, the use of motor vehicles, pharmaceuticals and farming, such as the use of fertilizers, pesticides and herbicides.
An important activity is finding out where these compounds are released into the ecosystem. FATE coordinates several monitoring programmes and collects data from a number of laboratories in different European countries. This activity also includes collecting data about how the pollutants distribute themselves in the ecosystem by several mechanisms, such as rain, sewage, and waste disposal. FATE also acts as an intermediary between local laboratories and the European Commission regarding compliance to permitted levels of certain pollutants, where the measurement techniques must be comparable.
A second activity is trying to understand the mechanisms influencing the distribution of pollutants, such as the transport through the atmosphere of PCBs (Polychlorinated biphenyl compounds, highly toxic products that are not biodegradable). This is done by a dedicated team, using computer modeling. They help create maps identifying high risk areas, and areas that are vulnerable. For example, the presence of certain endocrine disrupters (compounds that affect hormonal systems in animals and humans) in rivers can interfere with the reproduction cycle of certain fish, but also end up in human food, explains Bidoglio.
The result of gathering this data is the creation of data bases and interactive maps. These maps show hotspots of pollutants, and also the areas that are specifically vulnerable. They also show how certain pollution levels evolve over time and change their location. Also by looking at different scenarios policy makers can be advised on what actions should be taken.