Parasiticides are veterinary pharmaceuticals very frequently used in pasture animals. Particularly substances of the classes of avermectins and milbemycins are very common. These substances are highly toxic to non-target organisms, often stable in the environment (persistent) and may potentially accumulative in organisms. The present project contributes to filling environmental data gaps for avermectins and milbemycins. In addition, risk management strategies for parasiticides used in pasture animals were evaluated with regard to their efficacy and practicability reducing the risk to dung or soil organisms.