Advocates for labeling genetically modified foods have announced their intent to trek from New York to D.C. to raise awareness for the issue. Genetically modified organisms (GMOs) have had their genetic material engineered to alter its traits and have been a source of controversy for decades, though the use of the technology in agriculture has caused perhaps the most agitation.

Patent-protected food crops engineered to resist commercial herbicides or produce their own pesticides from within the plant have raised questions about safety--do they introduce new allergens into the food chain? Do they increase antibiotic resistance?--and some say food engineered to have longer shelf life and better nutrition should be tested more. These concerns have led some environmental groups to advocate for either the elimination or labeling of GMOs.

The European Union already requires that GM and non-GM plants be separated. Several counties in California have passed measures banning GMOs, though there is currently no national standard to distinguish food with genetically engineered DNA from the au natural stuff.

This particular anti-GMO crowd includes food safety groups, organic and natural food organizations, and some food manufacturers. A perhaps less-expected ally is the religious group Shomeret Shalom Network for Jewish Nonviolence. Rabbi Lynn Gottlieb said in a statement, “People who view GMO food products as muktzeh, out of bounds for eco-kosher use, have a right to know which products contain GMO.”

According to a release, marchers “are expected to walk part or all of the 313 miles” from the U.N. to D.C. We’ll see how that goes.