No longer just a flavorful garnish, cilantro has taken center stage in studies that show how the leafy herb might be a new, low-cost solution to purifying drinking water. Popularly used in Mexican and Southeast Asian cuisine, cilantro is being hailed for its potential as a “biosorbent” that can remove lead and other toxic heavy metals from contaminated water.
Typically, water purification relies on advanced technology that uses activated carbon — an approach that is often too expensive for most developing countries, particularly rural areas. Thus, Douglas Schauer, Ph.D. has focused his research on biosorbents, low-cost and sustainable alternatives that rely on natural materials such as microbes and plants. In explaining the appeal of biosorbents, Schauer describes a scenario: “When the filter in a water purification pitcher needs to be changed, they could go outside, gather a handful of cilantro or some other plant, and presto, there’s a new filter ready to purify the water.”
Also known as coriander and Chinese parsley, the plant is easily grown both at home and in the wild, making it readily available for many developing countries afflicted by a contaminated water supply. The key to the plant’s success lies in the architecture of its outer cellular walls that make cilantro ideal for absorbing toxic metals such as lead. Results from small-scale experiments carried out in Mexico have supported Schauer’s research and have even suggested that cilantro was more effective at water purification than conventional methods.