September 12, 2013
Move Over Brita, Cilantro Is Nature’s Water Purifier
Lee Rannals for redOrbit.com - Your Universe Online
One favorite ingredient in salsa has been shown to help purify drinking water, according to findings presented at the 246th National Meeting & Exposition of the American Chemical Society.Douglas Schauer of Ivy Tech Community College says that cilantro is an inexpensive way to purify drinking water, helping to remove lead and other potentially toxic heavy metals from contaminated H2O. The spice, also known as coriander and Thai parsley, is cheap, widely available, and commonly used in Mexican and Southwest Asian dishes.
"Cilantro may seem too pricey for use in decontaminating large amounts of water for drinking and cooking," Schauer said. "However, cilantro grows wild in vast amounts in countries that have problems with heavy-metal water pollution. It is readily available, inexpensive and shows promise in removing certain metals, such as lead, copper and mercury, that can be harmful to human health."
Waste-water sampling of drainage water from Mexico City has shown that many toxic metals such as copper, lead, chromium, and nickel are present in large quantities in the water used for irrigation and as drinking water.
Conventional methods for removing heavy metals from water can be too expensive for use in developing countries, particularly in rural areas. The need for low-cost, sustainable alternatives is great, and this latest research shows that cilantro has promise as a natural biosorbent.
"Our goal is to find biosorbents that people in developing countries could obtain for nothing," Schauer explained. "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."
Shauer said that biosorbents like cilantro could be packed into teabag-like packets, reusable water filter cartridges or even tea infuser balls to help remove the heavy metals.
Schauer and his students worked with students at the Universidad Politécnica de Francisco I. Madero in Hidalgo, Mexico on this research. The team performed a preliminary screening of species in Mexico at the university's campus. Their experiments showed that cilantro may be more effective than activated carbon at removing heavy metals like lead from water.
The secret to cilantro's purifying power lies in the structure of the outer walls of the microscopic cells that make up the plant. The architecture of these walls make them ideal for absorbing heavy metals. Shauer said that other plants, such as parsley and culantro (also known as Mexican coriander) could have similar features and potentially work as biosorbents as well.