It seems to be getting more difficult to produce fruits and vegetables that are safe for human health and the environment. The agriculture industry continues to be impacted by manufacturers of genetically modified organisms (GMOs), and more than 70 percent of processed foods on the U.S. market contain some GMO ingredients. To date, there are no laws requiring production companies to mark which goods containing genetically modified foods.

Foods and products most likely to be genetically engineered are: corn, soybeans, canola or rapeseed, cottonseed oil, dairy and sugar beets. GMOs also impact meats, as many cattle, pigs, chickens and farm-raised fish are forced to eat genetically engineered corn and other modified foods in the last few months of their lives. Aspartame, an artificial sweetener used in NutraSweet and Equal brands, is also typically derived from GMOs.

The onus is on the consumer to be aware of what products certain stores sell. For instance, Trader Joe’s website explains that all Trader Joes’ trademarked products contain, “NO artificial flavors, colors or preservatives; NO genetically modified ingredients; NO MSG; and NO added Trans Fats.”

The Non-GMO Project, www.nongmoproject.org, began working with Whole Foods Market in 2009 to support the grocer’s brand, 365 Everyday Value, as a non-GMO brand. Products in the store with the “USDA Organic” label, according to Whole Foods Market’s website, are “created only with non-GMO ingredients.”

Whether shopping at one of these stores or another market, it is important to know how to interpret the Price Look Up (PLU) code. On produce stickers, organic items have a five-digit PLU code that begins with the number nine. Produce grown conventionally (and likely with pesticides) has a four-digit PLU that begins with the number four. GMO produce are marked with a five-digit PLU that begins with the number eight.

Even then, not all labels are true to their PLU code. The best way to be sure the produce item is pesticide and GMO free, look for a label that says “100% Certified Organic.” The Institute for Responsible Technology, www.responsibletechnology.org, is a resource for learning about GMOs, the health risks associated with GMO items and how to support legislation requiring adequate labeling of GMO products.