Uitklappen toxins

Particularly after a prolonged period of drought, intense downpours may cause micropollutants to end up in surface water. Such micropollutants could be tyre dust, copper from car brakes, microplastics, pesticides, veterinary pharmaceuticals or oil residue. Micropollutants are harmful to life in and around surface water. For many locations, hardly any data is available on the concentration of micropollutants in surface water. In most cases, the tests conducted by water management bodies only cover a few micropollutants, as such tests are quite costly.

Under certain conditions, the soil underneath bodies of water in former industrial locations can release toxins. The same goes for bodies of water in farmland. This risk is highest in hot weather and in water that has been stagnant for a prolonged period of time due to persistent drought. In warm temperatures, toxins or toxic residues (aka degradation products) are released more quickly. If they end up in the water, such substances will seriously harm life in and around the surface water. This risk is going to increase in the future, as we will see increasingly frequent warm and dry periods, alternating with torrential rain.

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