Despite comprehensive regulations, around 60 percent of Europe’s surface water and a quarter of its groundwater do not meet “good” standards. Agriculture bears most of the responsibility. First part of an in-depth investigation on our most precious resource.
From the beaches in Brittany, France, to the groundwater of Aragon, Spain; from the fertile plains of the Netherlands to the prosecco hills in Italy, we have looked into how progressive European Union water protection policies get watered down through limited monitoring and data collection; how the industry has managed to postpone important environmental texts using gaps in scientific knowledge, and how water pollution has impacted the lives of communities and aquatic environments throughout Europe.
“Why don’t we see mass deaths of fish in Europe today? Because the pollution is much more subtle, yet ubiquitous. You can’t see it, you can’t smell it, so you think the water is fine,” says Martina Vijver, ecotoxicologist and professor at the University of Leiden. Vijver has been analysing the effect of pollutants on aquatic life in her living laboratory in Leiden, a quiet university town outside of Amsterdam, since 2017.
The Living Lab in Leiden consists of a series of ditches, containing colonies of various organisms, in which the real-life conditions of aquatic environments are simulated. Where, in a standard lab, test organisms are subjected to one substance at a time, in the Living Lab, multiple interconnected elements come into play, just like in nature. “Conventional lab tests are good because they provide a fast screening that you can replicate anywhere in the world.
But they don’t replicate a real-life situation. If you’re well fed, don’t need to run from your predators, and a researcher treats you well, that will impact how you’ll respond to the toxic substances,” Vijver explains. She compares it to the difference between being in a small room with one other person versus being with a large group: heat, cigarette smoke and noise would affect us differently in these two scenarios, and the bigger the group, the greater the risk that we would end up becoming dehydrated and leaving with a headache.
In the Living Lab, Vijver introduces different man-made pollutants into the environment and looks at their impact on the connections between aquatic organisms. In an experiment with the neonicotinoid thiacloprid, an insecticide, Vijver and her team saw a dramatic decline in the numbers of “all the species groups studied, such as dragonflies, beetles and caddisflies.”
According to the EU Water Framework Directive, aquatic biology is one of the parameters examined in the course of water quality assessment. The assessment of ecological status focuses on selected aquatic plants and animals (generally phytoplankton, benthic aquatic flora, benthic invertebrates, and fish), which are used as indicators of the overall state of the water body. The assessment is generally based on species composition and abundance, but Vijver warns that abundance alone can be a misleading rubric.
“If after [application of a pollutant] you can count the same number of species as before, it doesn’t mean that the connection between the aquatic organisms has stayed the same.” For instance, algal bloom is usually caused by an overburden of nutrients. But in some cases, the nutrient levels haven’t changed. “So maybe another pollutant affected the population of organisms eating the algae. So, algae will bloom, which will subsequently affect the whole community,” Vijver says.