This practice helps to conserve water resources, but it raises questions about the potential transfer of chemicals, such as psychotropic drugs, into the plants that are consumed. Amid the scarcity of fresh water in many regions, farmers sometimes use treated wastewater to irrigate crops. Recent research by Johns Hopkins University in the United States revealed that some crops, such as tomatoes, carrots, and lettuce, tend to store these compounds mainly in their leaves, rather than in the parts we usually eat. For example, tomato leaves contain more than 200 times the concentration of pharmaceutical compounds found in the fruits, while carrot leaves...
