In regions where freshwater supplies are limited, farmers sometimes rely on treated wastewater to water their crops. While this practice helps conserve scarce water resources, it has raised concerns among regulators and consumers. Wastewater can contain trace amounts of various substances, including psychoactive medications commonly used to treat mental health conditions.
New research from Johns Hopkins University suggests that certain crops — tomatoes, carrots, and lettuce — tend to store these chemicals mainly in their leaves. This finding may be reassuring for people who eat tomatoes and carrots, since the parts we typically consume are the fruit and the roots rather than the leaves.
The study, published in Environmental Science and Technology, is part of a broader effort to understand the safety of irrigating…