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Fish that have been exposed to the highly addictive stimulant for several weeks show signs of withdrawal if deprived of the drug.
Human drug use can spill over into streams and rivers, because the chemicals pass through wastewater systems that weren’t designed to extract them. To study the effects of a common illicit drug on wildlife, Pavel Horký at the Czech University of Life Sciences Prague and his colleagues looked to brown trout, Salmo trutta.