Scientists from the Department of Civil and Environmental Engineering at the University of Washington genetically modified an ordinary houseplant to break down toxic molecules present in chlorinated water and gasoline. The Pothos Ivy plant was designed to express a protein called 2E1, which allows you to break down benzene and chloroform into components that the plant can use for its own needs. Target chemicals are found in small quantities in typical households that accumulate over time, but the size of their molecules is too small for HEPA filters to catch. Since the effects of these chemicals have been associated with cancer, this scientific achievement is good news for human health.
In his study published December 19, 2018 in the journal Environmental science and technology, researchers Long Zhang, Ryan Routsong and Stuart E. Strand described the process they used to modify ivy plants. The plant was chosen because it was stable and able to grow in a variety of conditions, and the protein used – P450 2E1, abbreviated "2E1" – is naturally present in all mammals. In humans, 2E1 is found in the liver and is included only for the decomposition of alcohol, so it does not help decompose air pollutants. For this reason, the team’s work has focused on making its functionality available outside the body — they call it the “green liver” concept.
A synthetic variant of the 2E1 protein, found in rabbits, was introduced into the ivy of the potos so that each cell expressed it. In tests in vitro after genetic modification, the concentration of chloroform after three days dropped by 82 percent, and six days later it was not found, and the concentration of benzene decreased by 75 percent by the eighth day in bubbles containing plants and the corresponding gases. To achieve the benefits of altered functionality at home, chemicals will need to be transferred to where the plant is located. “If you had a plant growing in a corner of a room, it would have a certain effect in that room,” said Stuart Strand, one of the scientists in the study. "But without an air flow, the molecule at the other end of the house can get to the plant for a long time."
Benzene is a common industrial chemical used in the production of plastics, dyes, detergents and pesticides, among other things, and is commonly found in both rural and urban areas. Its connection with cancer is very clear – the most common is leukemia – which led to significant regulation. While the amount that is most exposed is very small, it can accumulate over time, especially in areas with heavy traffic, cigarette vapors and low ventilation. Chloroform is a chemical that can be released into the air when chlorine is used to clean drinking water, wastewater, and swimming pools. Despite the lack of a direct link between cancer and chloroform inhalation, the Environmental Protection Agency (EPA) considers it a likely human carcinogen due to studies linking high oral exposure with cancer.
The process of bringing the plant into operation took more than two years for the team, a considerable time compared with the months-long processes of other similar modification projects. However, the time spent was considered expedient due to both the results achieved and the durability of the installation used. They are now working to add formaldehyde degradation to the plant’s capabilities using another protein. Formaldehyde is a substance found in most building products and tobacco smoke, which is also associated with cancer, asthma, and allergies.